Gene Summary

Gene:KRT18; keratin 18
Aliases: K18, CK-18, CYK18
Summary:KRT18 encodes the type I intermediate filament chain keratin 18. Keratin 18, together with its filament partner keratin 8, are perhaps the most commonly found members of the intermediate filament gene family. They are expressed in single layer epithelial tissues of the body. Mutations in this gene have been linked to cryptogenic cirrhosis. Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2008]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:keratin, type I cytoskeletal 18
Source:NCBIAccessed: 31 August, 2019


What does this gene/protein do?
Show (17)
Pathways:What pathways are this gene/protein implicaed in?
Show (1)

Cancer Overview

Research Indicators

Publications Per Year (1994-2019)
Graph generated 31 August 2019 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Neoplasm Invasiveness
  • Antineoplastic Agents
  • RNA
  • Adenocarcinoma
  • Cancer Gene Expression Regulation
  • Cell Movement
  • Epithelial-Mesenchymal Transition
  • Keratins
  • Cervical Cancer
  • Vimentin
  • siRNA
  • Tunisia
  • Base Sequence
  • Up-Regulation
  • Disease Progression
  • Gene Knockdown Techniques
  • Gene Expression
  • Liver Cancer
  • Biomarkers, Tumor
  • Stomach Cancer
  • Keratin-18
  • Lymphatic Metastasis
  • Neoplasm Proteins
  • Sequence Homology, Nucleic Acid
  • Staging
  • Down-Regulation
  • Pinealoma
  • Androgen Receptors
  • Chromosome 12
  • Cell Proliferation
  • Messenger RNA
  • Molecular Sequence Data
  • Transfection
  • Keratin-8
  • Drug Resistance
  • Receptors, Steroid
  • Breast Cancer
  • Prostate Cancer
  • Gene Expression Profiling
  • Wilms Tumour
  • Oligonucleotide Array Sequence Analysis
  • Apoptosis
Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (6)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: KRT18 (cancer-related)

Shi R, Wang C, Fu N, et al.
Downregulation of cytokeratin 18 enhances BCRP-mediated multidrug resistance through induction of epithelial-mesenchymal transition and predicts poor prognosis in breast cancer.
Oncol Rep. 2019; 41(5):3015-3026 [PubMed] Related Publications
Multiple drug resistance (MDR) and metastasis have been identified as the two major causes of the poor prognosis of patients with breast cancer. However, the relationship between MDR and metastasis has not been characterized. Epithelial‑mesenchymal transition (EMT), a process known to promote metastasis in cancer, has been shown to be associated with the MDR phenotype of many tumor types. Reduced cytokeratin 18 (CK18) expression is thought to be one of the hallmarks of EMT, and the role of CK18 in MDR of metastatic breast cancer remains unknown. In the present study, we revealed that the expression of CK18 was significantly downregulated in breast cancer tissues and in an MDR cell line overexpressing breast cancer resistant protein (BCRP), and the presence of low levels of CK18 was associated with TNM stage, lymph node metastasis, and unfavorable survival in breast cancer patients. Further results demonstrated that CK18 stable knockdown using shRNA increased BCRP expression and induced the EMT process in human breast cancer MCF‑7 cells. Moreover, CK18 knockdown was associated with the activation of the NF‑κB/Snail signaling pathway, which has been revealed to regulate EMT and BCRP. Based on these findings, we concluded that CK18 knockdown enhanced BCRP‑mediated MDR in MCF‑7 cells through EMT induction partly via the NF‑κB/Snail pathway. These findings provide a valuable insight into the potential role of CK18 in MDR, migration and invasion of breast cancer cells. Reduced expression of CK18 may be a novel biomarker for predicting the poor prognosis of breast cancer patients.

Zeng W, Zhu JF, Liu JY, et al.
miR-133b inhibits cell proliferation, migration and invasion of esophageal squamous cell carcinoma by targeting EGFR.
Biomed Pharmacother. 2019; 111:476-484 [PubMed] Related Publications
BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor entity characterized by early metastasis and late diagnosis. MicroRNA-133b (miR-133b) has been considered as a tumor suppressor in many human cancers by regulating epidermal growth factor receptor (EGFR). However, the specific effects of miR-133b and EGFR on ESCC remain unclear.
METHODS: qRT-PCR and western blotting were applied for measuring expression of mRNA and protein. Flow cytometry was used for detecting cell cycle and apoptosis. Cell proliferation, migration and invasion were detected by colony formation and transwell assays. Luciferase reporter assay was used to confirm the interaction between miR-133b and EGFR.
RESULTS: Low expression of miR-133b and high expression of EGFR were identified in ESCC cells and tissues. Overexpression of miR-133b or knockdown of EGFR suppressed the cell proliferation, migration, and invasion of ESCC cells, and raised the percentage of G1 phase cells. The apoptosis of ESCC cells were promoted by increasing miR-133b and decreasing EGFR expression. Luciferase reporter assay confirmed EGFR as the target of miR-133b in ESCC cells. Overexpression of miR-133b significantly decreased the phosphorylation of PI3K, ERK and AKT by directly down-regulating EGFR. Higher expression of E-cadherin and CK-18 and lower expression of Vimentin and N-cadherin were observed after the transfection of miR-133b mimics or shEGFR.
CONCLUSION: Overexpression of miR-133b could suppress proliferation, migration and invasion of ESCC cells by inhibiting MAPK/ERK and PI3K/AKT signaling pathways through targeting EGFR, indicating that miR-133b might be a potential therapeutic target for the treatment of ESCC.

Ge Y, Zhu J, Wang X, et al.
Mapping dynamic histone modification patterns during arsenic-induced malignant transformation of human bladder cells.
Toxicol Appl Pharmacol. 2018; 355:164-173 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Arsenic is a known potent risk factor for bladder cancer. Increasing evidence suggests that epigenetic alterations, e.g., DNA methylation and histones posttranslational modifications (PTMs), contribute to arsenic carcinogenesis. Our previous studies have demonstrated that exposure of human urothelial cells (UROtsa cells) to monomethylarsonous acid (MMA

Gerashchenko GV, Mevs LV, Chashchina LI, et al.
Expression of steroid and peptide hormone receptors, metabolic enzymes and EMT-related genes in prostate tumors in relation to the presence of the TMPRSS2/ERG fusion.
Exp Oncol. 2018; 40(2):101-108 [PubMed] Related Publications
AIM: To analyze an expression pattern of the steroid and peptide hormone receptors, metabolic enzymes and EMT-related genes in prostate tumors in relation to the presence of the TMPRSS2/ERG fusion; and to examine a putative correlation between gene expression and clinical characteristics, to define the molecular subtypes of prostate cancer.
MATERIALS AND METHODS: The relative gene expression (RE) of 33 transcripts (27 genes) and the presence/absence of the TMPRSS2/ERG fusion were analyzed by a quantitative PCR. 37 prostate cancer tissues (T) paired with conventionally normal prostate tissue (CNT) and 21 samples of prostate adenomas were investigated. RE changes were calculated, using different protocols of statistics.
RESULTS: We demonstrated differences in RE of seven genes between tumors and CNT, as was calculated, using the 2-ΔCT model and the Wilcoxon matched paired test. Five genes (ESR1, KRT18, MKI67, MMP9, PCA3) showed altered expression in adenocarcinomas, in which the TMPRSS2/ERG fusion was detected. Two genes (INSR, isoform B and HOTAIR) expressed differently in tumors without fusion. Comparison of the gene expression pattern in adenomas, CNT and adenocarcinomas demonstrated that in adenocarcinomas, bearing the TMPRSS2/ERG fusion, genes KRT18, PCA3, and SCHLAP1 expressed differently. At the same time, we detected differences in RE of AR (isoform 2), MMP9, PRLR and HOTAIR in adenocarcinomas without the TMPRSS2/ERG fusion. Two genes (ESR1 and SRD5A2) showed differences in RE in both adenocarcinoma groups. Fourteen genes, namely AR (isoforms 1 and 2), CDH1, OCLN, NKX3-1, XIAP, GCR (ins AG), INSR (isoform A), IGF1R, IGF1R tr, PRLR, PRL, VDR and SRD5A2 showed correlation between RE and tumor stage. RE of four genes (CDH2, ESR2, VDR and SRD5A2) correlated with differentiation status of tumors (Gleason score). Using the K-means clustering, we could cluster adenocarcinomas in three groups, according to gene expression profiles. A specific subtype of prostate tumors is characterized by the activated ERG signaling, due to the presence of TMPRSS2/ERG fusion, and also by high levels of the androgen receptor, prolactin, IGF, INSR and PCA3.
CONCLUSIONS: We have found the specific differences in expression of the steroid and peptide hormone receptors, metabolic enzymes and EMT-related genes, depending on the pre-sence/absence of the TMPRSS2/ERG fusion in prostate adenocarcinomas, CNT and adenomas. We showed three different gene expression profiles of prostate adenocarcinomas. One of them is characteristic for adenocarcinomas with the TMPRSS2/ERG fusion. Further experiments are needed to confirm these data in a larger cohort of patients.

Cocco E, Leo M, Canzonetta C, et al.
KAT3B-p300 and H3AcK18/H3AcK14 levels are prognostic markers for kidney ccRCC tumor aggressiveness and target of KAT inhibitor CPTH2.
Clin Epigenetics. 2018; 10:44 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Background: Kidney cancer and clear cell renal carcinoma (ccRCC) are the 16th most common cause of death worldwide. ccRCC is often metastasized at diagnosis, and surgery remains the main treatment; therefore, early diagnosis and new therapeutic strategies are highly desirable. KAT inhibitor CPTH2 lowers histone H3 acetylation and induces apoptosis in colon cancer and cultured cerebellar granule neurons. In this study, we have evaluated the effects of CPTH2 on ccRCC 786-O cell line and analyzed drug targets expressed in ccRCC tumor tissues at different grade.
Results: CPTH2 decreases cell viability, adhesion, and invasiveness in ccRCC cell line 786-O. It shows preferential inhibition for KAT3B-p300 with hypoacetilating effects on histone H3 at specific H3-K18. Immunohistochemical analysis of 70 ccRCC tumor tissues compared with peritumoral normal epithelium showed a statistical significant reduction of p300/H3AcK18 paralleled by an increase of H3AcK14 in G1 grade and an opposed trend during tumor progression to worst grades. In this study, we demonstrate that these marks are CPTH2 targets and significative prognosticators of low-grade ccRCC tumor.
Conclusions: ccRCC is substantially insensitive to current therapies, and the efficacy of clinical treatment is dependent on the dissemination stage of the tumor. The present study shows that CPTH2 is able to induce apoptosis and decrease the invasiveness of a ccRCC cell line through the inhibition of KAT3B. In a tumor tissue analysis, we identified new prognosticator marks in grade G1 ccRCC tumors. Low KAT3B/H3AcK18 vs. high H3AcK14 were found in G1 while an opposed trend characterized tumor progression to worst grades. Our collected results suggest that CPTH2 reducing KAT3B and H3AcK18 can be considered a promising candidate for counteracting the progression of ccRCC tumors.

Jędroszka D, Orzechowska M, Hamouz R, et al.
Markers of epithelial-to-mesenchymal transition reflect tumor biology according to patient age and Gleason score in prostate cancer.
PLoS One. 2017; 12(12):e0188842 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
INTRODUCTION: Prostate carcinoma (PRAD) is one of the most frequently diagnosed malignancies amongst men worldwide. It is well-known that androgen receptor (AR) plays a pivotal role in a vast majority of prostate tumors. However, recent evidence emerged stating that estrogen receptors (ERs) may also contribute to prostate tumor development. Moreover, progression and aggressiveness of prostate cancer may be associated with differential expression genes of epithelial-to-mesenchymal transition (EMT). Therefore we aimed to assess the significance of receptors status as well as EMT marker genes expression among PRAD patients in accordance to their age and Gleason score.
MATERIALS AND METHODS: We analyzed TCGA gene expression profiles of 497 prostate tumor samples according to 43 genes involved in EMT and 3 hormone receptor genes (AR, ESR1, ESR2) as well as clinical characteristic of cancer patients. Then patients were divided into four groups according to their age and 5 groups according to Gleason score. Next, we evaluated PRAD samples according to relationship between the set of variables in different combinations and compared differential expression in subsequent groups of patients. The analysis was applied using R packages: FactoMineR, gplots, RColorBrewer and NMF.
RESULTS: MFA analysis resulted in distinct grouping of PRAD patients into four age categories according to expression level of AR, ESR1 and ESR2 with the most distinct group of age less than 50 years old. Further investigations indicated opposite expression profiles of EMT markers between different age groups as well as strong association of EMT gene expression with Gleason score. We found that depending on age of prostate cancer patients and Gleason score EMT genes with distinctly altered expression are: KRT18, KRT19, MUC1 and COL4A1, CTNNB1, SNAI2, ZEB1 and MMP3.
CONCLUSIONS: Our major observation is that prostate cancer from patients under 50 years old compared to older ones has entirely different EMT gene expression profiles showing potentially more aggressive invasive phenotype, despite Gleason score classification.

Vastrad B, Vastrad C, Tengli A, Iliger S
Identification of differentially expressed genes regulated by molecular signature in breast cancer-associated fibroblasts by bioinformatics analysis.
Arch Gynecol Obstet. 2018; 297(1):161-183 [PubMed] Related Publications
OBJECTIVE: Breast cancer is a severe risk to public health and has adequately convoluted pathogenesis. Therefore, the description of key molecular markers and pathways is of much importance for clarifying the molecular mechanism of breast cancer-associated fibroblasts initiation and progression. Breast cancer-associated fibroblasts gene expression dataset was downloaded from Gene Expression Omnibus database.
METHODS: A total of nine samples, including three normal fibroblasts, three granulin-stimulated fibroblasts and three cancer-associated fibroblasts samples, were used to identify differentially expressed genes (DEGs) between normal fibroblasts, granulin-stimulated fibroblasts and cancer-associated fibroblasts samples. The gene ontology (GO) and pathway enrichment analysis was performed, and protein-protein interaction (PPI) network of the DEGs was constructed by NetworkAnalyst software.
RESULTS: Totally, 190 DEGs were identified, including 66 up-regulated and 124 down-regulated genes. GO analysis results showed that up-regulated DEGs were significantly enriched in biological processes (BP), including cell-cell signalling and negative regulation of cell proliferation; molecular function (MF), including insulin-like growth factor II binding and insulin-like growth factor I binding; cellular component (CC), including insulin-like growth factor binding protein complex and integral component of plasma membrane; the down-regulated DEGs were significantly enriched in BP, including cell adhesion and extracellular matrix organization; MF, including N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase activity and calcium ion binding; CC, including extracellular space and extracellular matrix. WIKIPATHWAYS analysis showed the up-regulated DEGs were enriched in myometrial relaxation and contraction pathways. WIKIPATHWAYS, REACTOME, PID_NCI and KEGG pathway analysis showed the down-regulated DEGs were enriched endochondral ossification, TGF beta signalling pathway, integrin cell surface interactions, beta1 integrin cell surface interactions, malaria and glycosaminoglycan biosynthesis-chondroitin sulfate/dermatan sulphate. The top 5 up-regulated hub genes, CDKN2A, MME, PBX1, IGFBP3, and TFAP2C and top 5 down-regulated hub genes VCAM1, KRT18, TGM2, ACTA2, and STAMBP were identified from the PPI network, and subnetworks revealed these genes were involved in significant pathways, including myometrial relaxation and contraction pathways, integrin cell surface interactions, beta1 integrin cell surface interaction. Besides, the target hsa-mirs for DEGs were identified. hsa-mir-759, hsa-mir-4446-5p, hsa-mir-219a-1-3p and hsa-mir-26a-5p were important miRNAs in this study.
CONCLUSIONS: We pinpoint important key genes and pathways closely related with breast cancer-associated fibroblasts initiation and progression by a series of bioinformatics analysis on DEGs. These screened genes and pathways provided for a more detailed molecular mechanism underlying breast cancer-associated fibroblasts occurrence and progression, holding promise for acting as molecular markers and probable therapeutic targets.

Doebar SC, Sieuwerts AM, de Weerd V, et al.
Gene Expression Differences between Ductal Carcinoma in Situ with and without Progression to Invasive Breast Cancer.
Am J Pathol. 2017; 187(7):1648-1655 [PubMed] Related Publications
To understand the molecular alterations driving the progression of ductal carcinoma in situ (DCIS), we compared patients with pure DCIS and patients with DCIS and synchronous invasive breast cancer (IBC). Twelve patients with extensive pure DCIS were included as a representation of indolent lesions with limited invasive capacity. These cases were matched with 12 patients with a limited DCIS component and IBC, representing lesions with a high invasive potential. Matching included age and surrogate DCIS subtypes. Gene expression profiling was performed on DCIS cells to identify transcriptional differences between these two groups. The identified genes were validated by immunohistochemistry. Nine genes showed significantly different expression. Most of these genes were highly expressed in DCIS samples with IBC, including PLAU (P = 0.002), COL1A1 (P = 0.006), KRT81 (P = 0.009), S100A7 (P = 0.015), SCGB1D2 (P = 0.023), KRT18 (P = 0.029), and NOTCH3 (P = 0.044), whereas EGFR and CXCL14 showed a higher expression in cases with pure DCIS (P = 0.015 and P = 0.028, respectively). This difference was only significant for SCGB1D2 (P = 0.009). Hierarchical clustering revealed distinct clustering of patients with and without invasion. Patients with pure DCIS have a different gene expression pattern as compared to patients with DCIS and synchronous IBC. These genes may pinpoint to driver pathway(s) that play an important role in DCIS progression.

Akashi E, Fujihara S, Morishita A, et al.
Effects of galectin-9 on apoptosis, cell cycle and autophagy in human esophageal adenocarcinoma cells.
Oncol Rep. 2017; 38(1):506-514 [PubMed] Related Publications
The incidence of esophageal adenocarcinoma (EAC) is rapidly increasing in western countries. The overall mortality of this disease remains high with a 5-year survival rate of less than 20%, despite remarkable advances in the care of patients with EAC. Galectin-9 (Gal-9) is a tandem-repeat type galectin that exerts anti-proliferative effects on various cancer cell types. The aim of the present study was to evaluate the effects of Gal-9 on human EAC cells and to assess the expression of microRNAs (miRNAs) associated with the antitumor effects of Gal-9 in vitro. Gal-9 suppressed the proliferation of the EAC cell lines OE19, OE33, SK-GT4, and OACM 5.1C. Additionally, Gal-9 treatment induced apoptosis and increased the expression levels of caspase-cleaved cytokeratin 18, activated caspase-3 and activated caspase-9. However, it did not promote cell cycle arrest by reducing cell cycle-related protein levels. Furthermore, Gal-9 increased the level of the angiogenesis-related protein interleukin-8 (IL-8) and markedly altered miRNA expression. Based on these findings, Gal-9 may be of clinical use for the treatment of EAC.

Zhao SG, Chang SL, Erho N, et al.
Associations of Luminal and Basal Subtyping of Prostate Cancer With Prognosis and Response to Androgen Deprivation Therapy.
JAMA Oncol. 2017; 3(12):1663-1672 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Importance: There is a clear need for a molecular subtyping approach in prostate cancer to identify clinically distinct subgroups that benefit from specific therapies.
Objectives: To identify prostate cancer subtypes based on luminal and basal lineage and to determine associations with clinical outcomes and response to treatment.
Design, Setting, and Participants: The PAM50 classifier was used to subtype 1567 retrospectively collected (median follow-up, 10 years) and 2215 prospectively collected prostate cancer samples into luminal- and basal-like subtypes.
Main Outcomes and Measures: Metastasis, biochemical recurrence, overall survival, prostate cancer–specific survival, associations with biological pathways, and clinicopathologic variables were the main outcomes.
Results: Among the 3782 samples, the PAM50 classifier consistently segregated prostate cancer into 3 subtypes in both the retrospective and prospective cohorts: luminal A (retrospective, 538 [34.3%]; prospective, 737 [33.3%]), luminal B (retrospective, 447 [28.5%]; prospective, 723 [32.6%]), and basal (retrospective, 582 [37.1%]; prospective, 755 [34.1%]). Known luminal lineage markers, such as NKX3.1 and KRT18, were enriched in luminal-like cancers, and the basal lineage CD49f signature was enriched in basal-like cancers, demonstrating the connection between these subtypes and established prostate cancer biology. In the retrospective cohort, luminal B prostate cancers exhibited the poorest clinical prognoses on both univariable and multivariable analyses accounting for standard clinicopathologic prognostic factors (10-year biochemical recurrence-free survival [bRFS], 29%; distant metastasis-free survival [DMFS], 53%; prostate cancer-specific survival [PCSS], 78%; overall survival [OS], 69%), followed by basal prostate cancers (10-year bRFS, 39%; DMFS, 73%; PCSS, 86%; OS, 80%) and luminal A prostate cancers (10-year bRFS, 41%; DMFS, 73%; PCSS, 89%; OS, 82%). Although both luminal-like subtypes were associated with increased androgen receptor expression and signaling, only luminal B prostate cancers were significantly associated with postoperative response to androgen deprivation therapy (ADT) in a subset analysis in our retrospective cohorts (n = 315) matching patients based on clinicopathologic variables (luminal B 10-year metastasis: treated, 33% vs untreated, 55%; nonluminal B 10-year metastasis: treated, 37% vs untreated, 21%; P = .006 for interaction).
Conclusions and Relevance: Luminal- and basal-like prostate cancers demonstrate divergent clinical behavior, and patients with luminal B tumors respond better to postoperative ADT than do patients with non–luminal B tumors. These findings contribute novel insight into prostate cancer biology, providing a potential clinical tool to personalize ADT treatment for prostate cancer by predicting which men may benefit from ADT after surgery.

Yin H, Meng T, Zhou L, et al.
FOXD3 regulates anaplastic thyroid cancer progression.
Oncotarget. 2017; 8(20):33644-33651 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Anaplastic thyroid cancer (ATC) is an aggressive malignancy with poor prognosis. It was reported that Forkhead box D3 (FOXD3) transcription factor is associated with several cancers. We investigated its antitumorigenic role of ATC in this study. The ATC cell lines SW1736 and K18 exhibited lower FOXD3 expression than the Nthy-ori-3-1 normal thyroid cell line. FOXD3 downregulation in ATC cell lines promoted invasiveness and epithelial-to-mesenchymal transition (EMT) and decreased cellular apoptosis. FOXD3 silencing also enhanced p-ERK levels in the ATC cell lines, suggesting it negatively regulated MAPK/ERK signaling. Silencing FOXD3 in SW1736 cells also led to generation of larger xenograft tumors with high p-ERK and low E-cadherin levels. Moreover, human ATC samples showed lower FOXD3 and higher p-ERK levels than samples of normal thyroid tissue. These findings demonstrate that FOXD3 acts as a tumor suppressor during anaplastic thyroid carcinogenesis and highlight its potential for clinical application.

Ye T, Xu J, Du L, et al.
Downregulation of UBAP2L Inhibits the Epithelial-Mesenchymal Transition via SNAIL1 Regulation in Hepatocellular Carcinoma Cells.
Cell Physiol Biochem. 2017; 41(4):1584-1595 [PubMed] Related Publications
BACKGROUND/AIMS: Dysregulation of ubiquitin-associated protein 2-like (UBAP2L) has been reported in tumors, but its role in hepatocellular carcinoma (HCC) progression is unclear.
METHODS: The expression levels of UBAP2L in HCC tissues and HCC cell lines were detected by western blot and quantitative real-time (qRT) PCR. The effects of UBAP2L expression on HCC cell biological traits, including migration and invasion, were investigated by wound healing assay and matrigel transwell assay. Simultaneously, the expression of epithelial-mesenchymal transition (EMT) markers including E-cadherin, CK-18, N-cadherin, Vimentin, Claudin7 and the promoter activity of E-cadherin were detected by western blot and qRT-PCR. Subsequently, role of SNAIL1 in UBAP2L-mediated EMT and the mechanism underlying UBAP2L-mediated SNAIL1 expression were further investigated.
RESULTS: UBAP2L was overexpressed in human HCC tissues compared with peri-tumoral tissues. Downregulation of UBAP2L inhibited migration, invasion and the EMT in highly metastatic HCC cell lines. Furthermore, UBAP2L knockdown inhibited expression of the transcriptional repressor SNAIL1 and its ability to bind to the E-cadherin promoter via SMAD2 signaling pathway, which in turn resulted in increased E-cadherin expression. Additionally, bioinformatics analysis showed that expression of UBAP2L is correlated with poor prognosis in patients with HCC.
CONCLUSIONS: UBAP2L plays a critical role in maintenance of the metastatic ability of HCC cells via SNAIL1 Regulation and is predictive of a poor clinical outcome.

Feng X, Han H, Zou D, et al.
Suberoylanilide hydroxamic acid-induced specific epigenetic regulation controls Leptin-induced proliferation of breast cancer cell lines.
Oncotarget. 2017; 8(2):3364-3379 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Breast cancer is one of the most common malignancies among women in the world, investigating the characteristics and special transduction pathways is important for better understanding breast development and tumorigenesis. Leptin, a peptide hormone secreted from white adipocytes, may be an independent risk factor for breast cancer.Here, we treated suberoylanilide hydroxamic acid (SAHA) on Leptin-induced cell proliferation and invasion in the estrogen-receptor-positive breast cancer cell line MCF-7 and triple-negative breast cancer cell line MDA-MB-231. Low concentrations of Leptin (0.625 nM) significantly stimulated breast cancer cell growth, enhanced cell viability, minimized apoptosis, and increased cell cycle transition. In contrast, SAHA (5 μM) treatment had reverse effects. Wound healing assay showed that, in MCF-7 and MDA-MB-231 cell line, cell migrating stimulated by Leptin was significantly repressed with SAHA treatment. Moreover, cell cycle real-time PCR array and proteome profiler antibody array confirmed that Leptin and SAHA treatment significantly changed the expressions of factors associated with cell cycle regulation and apoptosis including p53 and p21WAF1/CIP1.In DNA-ChIP analysis, we found that acetylation levels binding with p21WAF1/CIP1 promoters are regulated in a manner specific to histone type, lysine residue and selective promoter regions. SAHA significantly up-regulated the acetylation levels of AcH3-k14 and AcH3-k27 in MCF-7 cells, whereas Leptin repressed the modification. In addition, SAHA or Leptin had no significant effects on the AcH4 acetylation binding with any regions of p21WAF1/CIP1 promoter. In MDA-MB-231 cells, SAHA alone or in combination with Leptin significantly increased acetylation levels of Ach3-k27, Ach3-k18 and Ach4-k5 residues. However, no clear change was found with Leptin alone at all. Overall, our data will inform future studies to elucidate the mechanisms of p21WAF1/CIP1 transcriptional regulation, and the functional roles of p21WAF1/CIP1 in breast cancer tumorigenesis.

Yang MR, Zhang Y, Wu XX, Chen W
Critical genes of hepatocellular carcinoma revealed by network and module analysis of RNA-seq data.
Eur Rev Med Pharmacol Sci. 2016; 20(20):4248-4256 [PubMed] Related Publications
OBJECTIVE: RNA-seq data of hepatocellular carcinoma (HCC) was analyzed to identify critical genes related to the pathogenesis and prognosis.
MATERIALS AND METHODS: Three RNA-seq datasets of HCC (GSE69164, GSE63863 and GSE55758) were downloaded from Gene Expression Omnibus (GEO), while another dataset including 54 HCC cases with survival time was obtained from The Cancer Genome Atlas (TCGA). Differentially expressed genes (DEGs) were identified by significant analysis of microarrays (SAM) method using package samr of R. As followed, we constructed a protein-protein interaction (PPI) network based on the information in Human Protein Reference Database (HPRD). Modules in the PPI network were identified with MCODE method using plugin clusterViz of CytoScape. Gene Ontology (GO) enrichment analysis and pathway enrichment analysis were performed with DAVID. The difference in survival curves was analyzed with Kaplan-Meier (K-M) method using package survival.
RESULTS: A total of 2572 DEGs were identified in the 3 datasets from GEO (GSE69164, GSE63863 and GSE55758). The PPI network was constructed including 660 nodes and 1008 edges, and 4 modules were disclosed in the network. Module A (containing 244 DEGs) was found to related to HCC closely, which genes were involved in transcription factor binding, protein metabolism as well as regulation of apoptosis. Nine hub genes were identified in the module A, including PRKCA, YWHAZ, KRT18, NDRG1, HSPA1A, HSP90AA1, HSF1, IKGKB and UBE21. The network provides the protein-protein interaction of these critical genes, which were implicated in the pathogenesis of HCC. Survival analysis showed that there is a significant difference between two groups classified by the genes in module A. Further Univariate Cox regression analysis showed that 72 genes were associated with survival time significantly, such as NPM1, PRKDC, SPARC, HMGA1, COL1A1 and COL1A2.
CONCLUSIONS: Nine critical genes related to the pathogenesis and 72 potential prognostic markers were revealed in HCC by the network and module analysis of RNA-seq data. These findings could improve the understanding of the pathogenesis and provide valuable information to further investigate the prognostic markers of HCC.

Zhang B, Wang J, Liu W, et al.
Cytokeratin 18 knockdown decreases cell migration and increases chemosensitivity in non-small cell lung cancer.
J Cancer Res Clin Oncol. 2016; 142(12):2479-2487 [PubMed] Related Publications
PURPOSE: Cytokeratin 18 (CK18) is a structural protein that is normally expressed in many single-layer epithelia. Previous studies have indicated that aberrant CK18 expression is associated with cancer progression. However, the functions of CK18 in lung cancer have not been fully elucidated. Here, we investigate the roles of CK18 in non-small cell lung cancer (NSCLC).
METHODS: CK18 protein expression was evaluated by immunohistochemistry in a lung cancer tissue microarray containing 129 cancer samples, and correlations between CK18 expression and clinicopathological characteristics and prognosis were analyzed. We then studied the effects of CK18 knockdown on cell motility and chemosensitivity in lung cancer cells.
RESULTS: High CK18 expression was detected in 101/129 (78.3 %) lung cancers. CK18 expression was significantly correlated to clinical stage, lymph node metastasis, the number of pathologically positive lymph nodes and recurrence and metastasis. Kaplan-Meier survival analysis showed that CK18 was a prognostic factor for overall survival (P = 0.016) and disease-free survival (P = 0.014). In addition, CK18 knockdown decreased cell migration and enhanced the sensitivity of lung cancer cells to paclitaxel.
CONCLUSIONS: These findings indicate that CK18 plays an important role in lung cancer progression and may be a therapeutic target for NSCLC.

Kilic-Baygutalp N, Ozturk N, Orsal-Ibisoglu E, et al.
Evaluation of serum HGF and CK18 levels in patients with esophageal cancer.
Genet Mol Res. 2016; 15(3) [PubMed] Related Publications
Cytokeratins are thought to play a role in apoptosis. Cytokeratin 18 (CK18) is involved in the formation of intracellular cytoskeleton, and has been considered a promising apoptosis marker in gastrointestinal carcinomas. Growth factors, including hepatocyte growth factor (HGF), may provide a microenvironment for malignant cells. In this study, we aimed to compare serum HGF and CK18 levels between esophageal squamous cell carcinoma patients and healthy controls. The study included 41 adult patients (20 male, 21 female) diagnosed with esophageal squamous cell carcinoma, with a mean age of 63.54 ± 10.88 years (range, 41-82 years). We also recruited 39 age and gender-matched healthy control subjects. Venous blood samples were taken; serum HGF and CK18 concentrations were determined via ELISA. Results indicated that serum HGF levels were higher in patients (1.37 ± 0.63 ng/mL) as compared to the healthy subjects (0.41 ± 0.29 ng/mL). Similarly, serum CK18 levels were higher in the patient group (2.53 ± 1.33 ng/mL) than in the control group (0.34 ± 0.23 ng/mL) (P < 0.001). In addition, serum HGF and CK18 levels were positively correlated with metastasis stage, tumor stage, and disease stage of esophageal squamous cell carcinoma. To our knowledge, this is the first study to evaluate serum HGF and CK18 levels in patients with esophageal squamous cell carcinoma. The results suggest that serum CK18 and HGF levels may be used as prognostic and disease monitoring biomarkers of esophageal squamous cell carcinoma.

Shourideh M, DePriest A, Mohler JL, et al.
Characterization of fibroblast-free CWR-R1ca castration-recurrent prostate cancer cell line.
Prostate. 2016; 76(12):1067-77 [PubMed] Related Publications
BACKGROUND: The previously established CWR-R1 cell line has been used as an in vitro model representing castration-recurrent prostate cancer. Microscopic observation of subconfluent cells demonstrated two distinct cellular morphologies: polygonal closely aggregated epithelial cells surrounded by bipolar fibroblastic cells with long processes. This study sought to establish and characterize a fibroblast-free derivative of the CWR-R1 cell line.
METHODS: The CWR-R1ca cell line was established from CWR-R1 cells by removing fibroblasts using multiple cycles of short-term trypsinization, cloning, and pooling single-cell colonies. Authentication of fibroblast-free CWR-R1ca cells was demonstrated by analyzing the expression of cytodifferentiation and prostate-associated markers, DNA and cytogenetic profiling, and growth pattern in the absence or presence of androgen.
RESULTS: CWR-R1ca is an androgen-sensitive cell line that expresses the androgen receptor (AR) and its splice variant 7 and the luminal epithelia markers, CK-8, CK-18, and c-Met. CWR-R1fb fibroblasts isolated from CWR-R1 cells express AR, hepatocyte growth factor-α, and mouse β-actin but not AR-V7 or epithelial markers. Cytogenetic analysis of CWR-R1ca cells revealed a hyperdiploid male with numerical gains in chromosomes 1, 7, 8, 10, 11, and 12, deletion of one chromosome 2 allele, structural abnormalities that include der(1)t(1:4), der(4)t(2:4), der(10)t(4:10), and an unbalanced reciprocal translocation between chromosome 6 and 14. DNA-profiling revealed that CWR-R1ca cells had significant short-tandem repeat marker homology with CWR22Pc and CWR22Rv1 cell lines, which indicated lineage derivation from CWR22 prostate cancer xenografts. CWR-R1ca cells were responsive to the growth stimulatory effects of dihydrotestosterone (DHT) in the femtomolar range.
CONCLUSION: This study establishes CWR-R1ca cells as a fibroblast-free derivative of the castration-recurrent CWR-R1 cell line. Prostate 76:1067-1077, 2016. © 2016 Wiley Periodicals, Inc.

Akiba J, Nakashima O, Hattori S, et al.
The expression of arginase-1, keratin (K) 8 and K18 in combined hepatocellular-cholangiocarcinoma, subtypes with stem-cell features, intermediate-cell type.
J Clin Pathol. 2016; 69(10):846-51 [PubMed] Related Publications
AIMS: The WHO classification describes that combined hepatocellular-cholangiocarcinoma, subtypes with stem-cell features, intermediate-cell subtype (CHC-INT) is composed of tumour cells with features intermediate between hepatocytes and cholangiocytes. However, we previously reported that CHC-INT showed a high positive rate of biliary markers, but the expression of hepatocyte paraffin (HepPar)-1 was low. In this study, we examined the expression of other hepatocyte markers, such as arginase-1 (Arg-1), keratin (K) 8 and K18 in CHC-INT in order to examine the utility of pathological diagnosis in CHC-INT.
METHODS: We performed immunohistochemistry (IHC) of Arg-1, K8 and K18 using 32 previously diagnosed as CHC-INT. Immunoreactivity was evaluated with grading from 0 to 4 according to the distribution area of positive cells. The obtained findings of Arg-1, K8 and K18 were compared with those of K7, K19 and HepPar-1.
RESULTS: Out of the 32 cases, 22 (68.8%) cases were positive for Arg-1. Twenty-five (78.1%) were positive for K8. The IHC scores of Arg-1 and K8 were significantly higher than those of HepPar-1, but significantly lower than those of K7 and K19. The K18 expression was widely observed in all cases (100%). The IHC score of Arg-1 and K8 in CHC-INT was intermediate between hepatocellular carcinoma and cholangiocarcinoma.
CONCLUSIONS: Arg-1 and K8 were good markers to identify intermediate cells between hepatocytes and cholangiocytes. These can be useful markers for pathological diagnosis of CHC-INT, which usually has wide histological diversities, in combination with other hepatocytic and/or cholangiocytic markers.

Trisdale SK, Schwab NM, Hou X, et al.
Molecular manipulation of keratin 8/18 intermediate filaments: modulators of FAS-mediated death signaling in human ovarian granulosa tumor cells.
J Ovarian Res. 2016; 9:8 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
BACKGROUND: Granulosa cell tumors (GCT) are a rare ovarian neoplasm but prognosis is poor following recurrence. Keratin intermediate filaments expressed in these tumors are a diagnostic marker, yet paradoxically, may also constitute a target for therapeutic intervention. In the current study, we evaluated keratin 8/18 (K8/18) filament expression as a mechanism of resistance to apoptosis in GCT, specifically focusing on regulation of the cell surface death receptor, Fas (FAS).
METHODS: The GCT cell line, KGN, was transiently transfected with siRNA to KRT8 and KRT18 to reduce K8/18 filament expression. Expression of K8/18, FAS, and apoptotic proteins (PARP, cleaved PARP) were evaluated by fluorescence microscopy, flow cytometric analysis, and immunoblotting, respectively. The incidence of FAS-mediated apoptosis in KGN cells was measured by caspase 3/7 activity. All experiments were performed independently three to six times, using a fresh aliquot of KGN cells for each experiment. Quantitative data were analyzed by one- or two-way analysis of variance (ANOVA), followed by a Tukey's post-test for multiple comparisons; differences among means were considered statistically significant at P < 0.05.
RESULTS: Control cultures of KGN cells exhibited abundant K8/18 filament expression (~90 % of cells), and minimal expression of FAS (<25 % of cells). These cells were resistant to FAS-activating antibody (FasAb)-induced apoptosis, as determined by detection of cleaved PARP and measurement of caspase 3/7 activity. Conversely, siRNA-mediated knock-down of K8/18 filament expression enhanced FAS expression (> 70 % of cells) and facilitated FasAb-induced apoptosis, evident by increased caspase 3/7 activity (P < 0.05). Additional experiments revealed that inhibition of protein synthesis, but not MEK1/2 or PI3K signaling, also prompted FasAb-induced apoptosis.
CONCLUSIONS: The results demonstrated that K8/18 filaments provide resistance to apoptosis in GCT by impairing FAS expression. The abundance of keratin filaments in these cells and their role in apoptotic resistance provides a greater mechanistic understanding of ovarian tumorgenicity, specifically GCT, as well as a clinically-relevant target for potential therapeutic intervention.

Hamilton JG, Mays D, DeMarco T, Tercyak KP
Modeling the dyadic effects of parenting, stress, and coping on parent-child communication in families tested for hereditary breast-ovarian cancer risk.
Fam Cancer. 2016; 15(4):513-22 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Genetic testing for BRCA genes, associated with hereditary breast-ovarian cancer risk, is an accepted cancer control strategy. BRCA genetic testing has both medical and psychosocial implications for individuals seeking testing and their family members. However, promoting open and adaptive communication about cancer risk in the family is challenging for parents of minor children. Using prospective data collected from mothers undergoing BRCA genetic testing and their untested co-parents (N = 102 parenting dyads), we examined how maternal and co-parent characteristics independently and conjointly influenced the overall quality of parent-child communication with minor children. Statistical associations were tested in accordance with the Actor-Partner Interdependence Model. Significant Actor effects were observed among mothers, such that open parent-child communication prior to genetic testing was positively associated with open communication 6 months following receipt of genetic test results; and among co-parents, more open parent-child communication at baseline and greater perceived quality of the parenting relationship were associated with more open parent-child communication at follow-up. Partner effects were also observed: co-parents' baseline communication and confidence in their ability to communicate with their minor children about genetic testing was positively associated with open maternal parent-child communication at follow-up. These results demonstrate that for families facing the prospect of cancer genetic testing, perceptions and behaviors of both members of child-rearing couples have important implications for the overall quality of communication with their minor children, including communication about cancer risk.

Ge F, Zhang H, Wang DD, et al.
Enhanced detection and comprehensive in situ phenotypic characterization of circulating and disseminated heteroploid epithelial and glioma tumor cells.
Oncotarget. 2015; 6(29):27049-64 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Conventional strategy of anti-EpCAM capture and immunostaining of cytokeratins (CKs) to detect circulating tumor cells (CTCs) is limited by highly heterogeneous and dynamic expression or absence of EpCAM and/or CKs in CTCs. In this study, a novel integrated cellular and molecular approach of subtraction enrichment (SE) and immunostaining-FISH (iFISH) was successfully developed. Both large or small size CTCs and circulating tumor microemboli (CTM) in various biofluid samples including cerebrospinal fluid (CSF) of cancer patients and patient-derived-xenograft (PDX) mouse models were efficiently enriched and comprehensively identified and characterized by SE-iFISH. Non-hematopoietic CTCs with heteroploid chromosome 8 were detected in 87-92% of lung, esophageal and gastric cancer patients. Characterization of CTCs performed by CK18-iFISH showed that CK18, the dual epithelial marker and tumor biomarker, was strong positive in only 14% of lung and 24% of esophageal CTCs, respectively. Unlike conventional methodologies restricted only to the large and/or both EpCAM and CK positive CTCs, SE-iFISH enables efficient enrichment and performing in situ phenotypic and karyotypic identification and characterization of the highly heterogeneous CTC subtypes classified by both chromosome ploidy and the expression of various tumor biomarkers. Each CTC subtype may possess distinct clinical significance relative to tumor metastasis, relapse, therapeutic drug sensitivity or resistance, etc.

Kobayashi K, Morishita A, Iwama H, et al.
Galectin-9 suppresses cholangiocarcinoma cell proliferation by inducing apoptosis but not cell cycle arrest.
Oncol Rep. 2015; 34(4):1761-70 [PubMed] Related Publications
Cholangiocarcinoma is the most common biliary malignancy and the second most common hepatic malignancy after hepatocellular carcinoma (HCC). Galectin-9 (Gal-9) is a tandem-repeat-type galectin that has recently been shown to exert antiproliferative effects on cancer cells. Therefore, the present study evaluated the effects of Gal-9 on the proliferation of human cholangiocarcinoma cells in vitro as well as the microRNAs (miRNAs) associated with the antitumor effects of Gal-9. Gal-9 suppressed the proliferation of cholangiocarcinoma cell lines in vitro and the growth of human cholangiocarcinoma cell xenografts in nude mice. Our data further revealed that Gal-9 increased caspase‑cleaved keratin 18 (CCK18) levels, and the expression of cytochrome c increased in Gal-9-treated cholangiocarcinoma cell lines. These data suggested that Gal-9 induced cholangiocarcinoma cell apoptosis via the intrinsic apoptosis pathway mediated by caspase-dependent or -independent pathways. In addition, Gal-9 reduced the phosphorylation of the epidermal growth factor receptor (EGFR), insulin-like growth factor and insulin-like growth factor-1 receptor (IGF-1R), hepatocyte growth factor receptor and fibroblast growth factor receptor 3 (FGFR3). These findings suggest that Gal-9 can be a candidate of therapeutic target in the treatment of cholangiocarcinoma.

Davalieva K, Kostovska IM, Kiprijanovska S, et al.
Proteomics analysis of malignant and benign prostate tissue by 2D DIGE/MS reveals new insights into proteins involved in prostate cancer.
Prostate. 2015; 75(14):1586-600 [PubMed] Related Publications
BACKGROUND: The key to a more effective diagnosis, prognosis, and therapeutic management of prostate cancer (PCa) could lie in the direct analysis of cancer tissue. In this study, by comparative proteomics analysis of PCa and benign prostate hyperplasia (BPH) tissues we attempted to elucidate the proteins and regulatory pathways involved in this disease.
METHODS: The samples used in this study were fresh surgical tissues with clinically and histologically confirmed PCa (n = 19) and BPH (n = 33). We used two dimensional difference in gel electrophoresis (2D DIGE) coupled with mass spectrometry (MS) and bioinformatics analysis.
RESULTS: Thirty-nine spots with statistically significant 1.8-fold variation or more in abundance, corresponding to 28 proteins were identified. The IPA analysis pointed out to 3 possible networks regulated within MAPK, ERK, TGFB1, and ubiquitin pathways. Thirteen of the identified proteins, namely, constituents of the intermediate filaments (KRT8, KRT18, DES), potential tumor suppressors (ARHGAP1, AZGP1, GSTM2, and MFAP4), transport and membrane organization proteins (FABP5, GC, and EHD2), chaperons (FKBP4 and HSPD1) and known cancer marker (NME1) have been associated with prostate and other cancers by numerous proteomics, genomics or functional studies. We evidenced for the first time the dysregulation of 9 proteins (CSNK1A1, ARID5B, LYPLA1, PSMB6, RABEP1, TALDO1, UBE2N, PPP1CB, and SERPINB1) that may have role in PCa. The UBE2N, PSMB6, and PPP1CB, involved in cell cycle regulation and progression were evaluated by Western blot analysis which confirmed significantly higher abundances of UBE2N and PSMB6 and significantly lower abundance of PPP1CB in PCa.
CONCLUSION: In addition to the identification of substantial number of proteins with known association with PCa, the proteomic approach in this study revealed proteins not previously clearly related to PCa, providing a starting point for further elucidation of their function in disease initiation and progression.

Wang X, Lao Y, Xu N, et al.
Oblongifolin C inhibits metastasis by up-regulating keratin 18 and tubulins.
Sci Rep. 2015; 5:10293 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Tumor metastasis is the main cause of cancer-related patient death. In this study, we performed a wound healing migration screen to search for a metastatic inhibitor within our library of natural compounds. We found that oblongifolin C (OC), a natural compound extracted from Garcinia yunnanensis Hu, is an effective inhibitor of metastasis in human esophageal squamous carcinoma Eca109 cells. The transwell migration and matrigel invasion assay results also showed that OC inhibits the migration of Eca109 cells and HepG2 cells. OC can increase the expression of tubulin, indicating that OC inhibits metastasis via tubulin aggregation. In addition, the Western blotting, real-time PCR, and immunostaining results indicated that OC increases the expression of keratin18. Furthermore, the knockdown of keratin 18 by small interfering RNAs inhibited the expression of tubulin and increased the metastasis of cancer cells, suggesting that keratin 18 is the upstream signal of tubulin and plays a vital role in metastasis. A subsequent study in a tail vein injection metastasis model showed that OC can significantly inhibit pulmonary metastasis, as revealed by immunohistochemistry staining. Taken together, our results suggest that OC inhibits metastasis through the induction of the expression of keratin 18 and may be useful in cancer therapy.

Li D, Song XY, Yue QX, et al.
Proteomic and bioinformatic analyses of possible target-related proteins of gambogic acid in human breast carcinoma MDA-MB-231 cells.
Chin J Nat Med. 2015; 13(1):41-51 [PubMed] Related Publications
Gambogic acid (GA) is an anticancer agent in phase ‖b clinical trial in China but its mechanism of action has not been fully clarified. The present study was designed to search the possible target-related proteins of GA in cancer cells using proteomic method and establish possible network using bioinformatic analysis. Cytotoxicity and anti-migration effects of GA in MDA-MB-231 cells were checked using MTT assay, flow cytometry, wound migration assay, and chamber migration assay. Possible target-related proteins of GA at early (3 h) and late stage (24 h) of treatment were searched using a proteomic technology, two-dimensional electrophoresis (2-DE). The possible network of GA was established using bioinformatic analysis. The intracellular expression levels of vimentin, keratin 18, and calumenin were determined using Western blotting. GA inhibited cell proliferation and induced cell cycle arrest at G2/M phase and apoptosis in MDA-MB-231 cells. Additionally, GA exhibited anti-migration effects at non-toxic doses. In 2-DE analysis, totally 23 possible GA targeted proteins were found, including those with functions in cytoskeleton and transport, regulation of redox state, metabolism, ubiquitin-proteasome system, transcription and translation, protein transport and modification, and cytokine. Network analysis of these proteins suggested that cytoskeleton-related proteins might play important roles in the effects of GA. Results of Western blotting confirmed the cleavage of vimentin, increase in keratin 18, and decrease in calumenin levels in GA-treated cells. In summary, GA is a multi-target compound and its anti-cancer effects may be based on several target-related proteins such as cytoskeleton-related proteins.

Vega ME, Giroux V, Natsuizaka M, et al.
Inhibition of Notch signaling enhances transdifferentiation of the esophageal squamous epithelium towards a Barrett's-like metaplasia via KLF4.
Cell Cycle. 2014; 13(24):3857-66 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Barrett's esophagus (BE) is defined as an incomplete intestinal metaplasia characterized generally by the presence of columnar and goblet cells in the formerly stratified squamous epithelium of the esophagus. BE is known as a precursor for esophageal adenocarcinoma. Currently, the cell of origin for human BE has yet to be clearly identified. Therefore, we investigated the role of Notch signaling in the initiation of BE metaplasia. Affymetrix gene expression microarray revealed that BE samples express decreased levels of Notch receptors (NOTCH2 and NOTCH3) and one of the the ligands (JAG1). Furthermore, BE tissue microarray showed decreased expression of NOTCH1 and its downstream target HES1. Therefore, Notch signaling was inhibited in human esophageal epithelial cells by expression of dominant-negative-Mastermind-like (dnMAML), in concert with MYC and CDX1 overexpression. Cell transdifferentiation was then assessed by 3D organotypic culture and evaluation of BE-lineage specific gene expression. Notch inhibition promoted transdifferentiation of esophageal epithelial cells toward columnar-like cells as demonstrated by increased expression of columnar keratins (K8, K18, K19, K20) and glandular mucins (MUC2, MUC3B, MUC5B, MUC17) and decreased expression of squamous keratins (K5, K13, K14). In 3D culture, elongated cells were observed in the basal layer of the epithelium with Notch inhibition. Furthermore, we observed increased expression of KLF4, a potential driver of the changes observed by Notch inhibition. Interestingly, knockdown of KLF4 reversed the effects of Notch inhibition on BE-like metaplasia. Overall, Notch signaling inhibition promotes transdifferentiation of esophageal cells toward BE-like metaplasia in part via upregulation of KLF4. These results support a novel mechanism through which esophageal epithelial transdifferentiation promotes the evolution of BE.

Drew JE, Farquharson AJ, Mayer CD, et al.
Predictive gene signatures: molecular markers distinguishing colon adenomatous polyp and carcinoma.
PLoS One. 2014; 9(11):e113071 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Cancers exhibit abnormal molecular signatures associated with disease initiation and progression. Molecular signatures could improve cancer screening, detection, drug development and selection of appropriate drug therapies for individual patients. Typically only very small amounts of tissue are available from patients for analysis and biopsy samples exhibit broad heterogeneity that cannot be captured using a single marker. This report details application of an in-house custom designed GenomeLab System multiplex gene expression assay, the hCellMarkerPlex, to assess predictive gene signatures of normal, adenomatous polyp and carcinoma colon tissue using archived tissue bank material. The hCellMarkerPlex incorporates twenty-one gene markers: epithelial (EZR, KRT18, NOX1, SLC9A2), proliferation (PCNA, CCND1, MS4A12), differentiation (B4GANLT2, CDX1, CDX2), apoptotic (CASP3, NOX1, NTN1), fibroblast (FSP1, COL1A1), structural (ACTG2, CNN1, DES), gene transcription (HDAC1), stem cell (LGR5), endothelial (VWF) and mucin production (MUC2). Gene signatures distinguished normal, adenomatous polyp and carcinoma. Individual gene targets significantly contributing to molecular tissue types, classifier genes, were further characterised using real-time PCR, in-situ hybridisation and immunohistochemistry revealing aberrant epithelial expression of MS4A12, LGR5 CDX2, NOX1 and SLC9A2 prior to development of carcinoma. Identified gene signatures identify aberrant epithelial expression of genes prior to cancer development using in-house custom designed gene expression multiplex assays. This approach may be used to assist in objective classification of disease initiation, staging, progression and therapeutic responses using biopsy material.

Wu L, Wang Y, Liu Y, et al.
A central role for TRPS1 in the control of cell cycle and cancer development.
Oncotarget. 2014; 5(17):7677-90 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
The eukaryotic cell cycle is controlled by a complex regulatory network, which is still poorly understood. Here we demonstrate that TRPS1, an atypical GATA factor, modulates cell proliferation and controls cell cycle progression. Silencing TRPS1 had a differential effect on the expression of nine key cell cycle-related genes. Eight of these genes are known to be involved in the regulation of the G2 phase and the G2/M transition of the cell cycle. Using cell synchronization studies, we confirmed that TRPS1 plays an important role in the control of cells in these phases of the cell cycle. We also show that silencing TRPS1 controls the expression of 53BP1, but not TP53. TRPS1 silencing also decreases the expression of two histone deacetylases, HDAC2 and HDAC4, as well as the overall HDAC activity in the cells, and leads to the subsequent increase in the acetylation of histone4 K16 but not of histone3 K9 or K18. Finally, we demonstrate that TRPS1 expression is elevated in luminal breast cancer cells and luminal breast cancer tissues as compared with other breast cancer subtypes. Overall, our study proposes that TRPS1 acts as a central hub in the control of cell cycle and proliferation during cancer development.

Kabir NN, Rönnstrand L, Kazi JU
Keratin 19 expression correlates with poor prognosis in breast cancer.
Mol Biol Rep. 2014; 41(12):7729-35 [PubMed] Related Publications
Breast cancer expression profiling has been used for determining biomarkers. Using gene expression profiles of 2,400 patients we identified keratin 19 (KRT19) as a highly deregulated gene in breast cancer. KRT19 expression is independent of patient race but correlates with disease grade, and ER, PR or HER2 expression. Expression of TPD52, GATA3 and KRT18 was increased in KRT19 expressing patients. Furthermore, KRT19 expression was associated with ER up-regulation and Luminal B gene signatures, as well as a constitutive RAF1 signaling pathway. Finally, KRT19 expression correlated with poor overall survival. Taken together, our results suggest that KRT19 expression can be used as a prognostic marker.

Zhang H, Chen X, Wang J, et al.
EGR1 decreases the malignancy of human non-small cell lung carcinoma by regulating KRT18 expression.
Sci Rep. 2014; 4:5416 [PubMed] Article available free on PMC after 15/09/2019 Related Publications
Early growth response 1 (EGR1) is a multifunctional transcription factor; Positive and negative functions of EGR1 in various tumors rely on the integrated functions of various genes it regulates. In this study, we observed the role of EGR1 in non-small-cell lung carcinoma (NSCLC) and identified genes that influence cell fate and tumor development. Various assays showed that EGR1 arrested cell mobility, inhibited migration, and induced apoptosis. Microarray analysis revealed that 100 genes, including CDKN1C, CDC27 and PRKDC, changed their mRNA expressions with the increase of EGR1 and contributed to intervention of tumor progression. Bioinformatics analysis and promoter analysis indicated that an EGR1 binding site was situated in the promoter of KRT18 (also named CK18) and KRT18 could assist in inhibition of NSCLC development. The expression level of EGR1 and KRT18 in NSCLC clinical cases was investigated by immunohistochemistry, in which the protein expression of KRT18 was found to be significantly associated with EGR1 and lymph node metastasis. The results collectively confirm that EGR1 functions as a tumor suppressor in NSCLC. This study is the first to report KRT18 expression is directly regulated by EGR1, and contributes to decrease malignancy of NSCLC.

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