Cancer Overview
Research Indicators
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.
Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex
Specific Cancers (10)
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).
Useful Links
CDK4
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
CDK4
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
CDK4
Cancer Genome Anatomy Project, NCI
Gene Summary
CDK4
COSMIC, Sanger Institute
Somatic mutation information and related details
CDK4
GEO Profiles, NCBI
Search the gene expression profiles from curated DataSets in the Gene Expression Omnibus (GEO) repository.
Latest Publications: CDK4 (cancer-related)
Lacking targetable molecular drivers, triple-negative breast cancer (TNBC) is the most clinically challenging subtype of breast cancer. In this study, we reveal that Death Effector Domain-containing DNA-binding protein (DEDD), which is overexpressed in > 60% of TNBCs, drives a mitogen-independent G1/S cell cycle transition through cytoplasm localization. The gain of cytosolic DEDD enhances cyclin D1 expression by interacting with heat shock 71 kDa protein 8 (HSC70). Concurrently, DEDD interacts with Rb family proteins and promotes their proteasome-mediated degradation. DEDD overexpression renders TNBCs vulnerable to cell cycle inhibition. Patients with TNBC have been excluded from CDK 4/6 inhibitor clinical trials due to the perceived high frequency of Rb-loss in TNBCs. Interestingly, our study demonstrated that, irrespective of Rb status, TNBCs with DEDD overexpression exhibit a DEDD-dependent vulnerability to combinatorial treatment with CDK4/6 inhibitor and EGFR inhibitor in vitro and in vivo. Thus, our study provided a rationale for the clinical application of CDK4/6 inhibitor combinatorial regimens for patients with TNBC.
BET-bromodomain inhibition (BETi) has shown pre-clinical promise for MYC-amplified medulloblastoma. However, the mechanisms for its action, and ultimately for resistance, have not been fully defined. Here, using a combination of expression profiling, genome-scale CRISPR/Cas9-mediated loss of function and ORF/cDNA driven rescue screens, and cell-based models of spontaneous resistance, we identify bHLH/homeobox transcription factors and cell-cycle regulators as key genes mediating BETi's response and resistance. Cells that acquire drug tolerance exhibit a more neuronally differentiated cell-state and expression of lineage-specific bHLH/homeobox transcription factors. However, they do not terminally differentiate, maintain expression of CCND2, and continue to cycle through S-phase. Moreover, CDK4/CDK6 inhibition delays acquisition of resistance. Therefore, our data provide insights about the mechanisms underlying BETi effects and the appearance of resistance and support the therapeutic use of combined cell-cycle inhibitors with BETi in MYC-amplified medulloblastoma.
Tak J, Sabarwal A, Shyanti RK, Singh RP
Berberine enhances posttranslational protein stability of p21/cip1 in breast cancer cells via down-regulation of Akt.Mol Cell Biochem. 2019; 458(1-2):49-59 [
PubMed]
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Berberine has shown anticancer properties and has potential for a chemopreventive and/or chemotherapeutic agent for breast cancer. Berberine showed cytotoxicity to breast cancer cells, with an increase in the levels of p21/cip1 and p27/kip1, cyclin-dependent kinase inhibitors (CDKI), but mechanisms involved in up-regulating these molecules are largely unknown. Herein, we studied the key regulatory mechanisms involved in berberine-mediated up-regulation of p21/cip1 and p27/kip1. Berberine treatment for 24 and 48 h decreased the number of cells by 44-84% (P < 0.0001) and 38-78% (P < 0.0001), and increased cell death by 12-17% (P < 0.005) and 38-78% (P < 0.0001) in MCF-7 and MDA-MB-231 cells, respectively. Cells were arrested in G1 phase by berberine which was accompanied with up-regulation of mRNA and protein level of both p21/cip1 and p27/kip1. Berberine decreased the expression of protein levels of cyclin D1, cyclin E, CDK2, CDK4, and CDK6 to cause G1 phase arrest. Berberine caused nuclear localization of p21/cip1 in both the cell lines. Our data for the first time showed that the post-translational stability of both the proteins was strongly increased by berberine as examined by cycloheximide chase assay. Inhibition of Akt was associated with berberine-mediated up-regulation of p21/cip1 and also led to a decrease in cell viability accompanied with significant G1 phase cell cycle arrest. Our study revealed that berberine not only up-regulates mRNA and protein levels of p21/cip1 and p27/kip1 but also increases their nuclear localization and post-translational protein stability. Further, Akt inhibition was found to mediate berberine-mediated up-regulation of p21/cip1 but not the p27/kip1.
Long-chain fatty acids are the most abundant fatty acids and are essential for various physiological processes. Translocation of long-chain fatty acids across cell membrane is dependent on transport proteins. Solute carrier family 27 member 6 (SLC27A6) is a transport protein which mediates long-chain fatty acid uptake. The bioinformatic analysis revealed that the expression of SLC27A6 in non-tumoral breast tissue was higher than that in tumoral breast cancer in clinic samples. When SLC27A6 expression in non-tumorigenic cell H184B5F5/M10 was repressed, the fatty acids uptake capacity and cell proliferation was inhibited, and cell cycle was delayed. The protein expression of cell cycle regulators including cell division protein kinase 4 (CDK4), CDK6, and cyclin D1 was significantly decreased in SLC27A6-silenced H184B5F5/M10. By contrast, relatively low SLC27A6 expression in tumorigenic breast cancer cell Hs578T when compared to H184B5F5/M10. Repressing SLC27A6 expression did not affect these phenotypes in Hs578T. The interaction network of SLC27A6 was further investigated via STRING database. The function of these SLC27A6-associated proteins mainly involved in lipid biosynthesis, fatty acid metabolic process, and fatty acid transport. In conclusion, this study reveals inverse correlation between SLC27A6 expression and tumoral tissues and provides a new insight into SLC27A6-mediated cell growth and cell cycle regulation in non-tumorigenic breast cells.
Ding Q, Li X, Sun Y, Zhang X
Schizandrin A inhibits proliferation, migration and invasion of thyroid cancer cell line TPC-1 by down regulation of microRNA-429.Cancer Biomark. 2019; 24(4):497-508 [
PubMed]
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OBJECTIVE: Schizandrin A (SchA) exerts anticancer potential. However, the effects of SchA on thyroid cancer (TC) have not been clear illuminated. Therefore, we investigated the effects of SchA on TC cell line TPC-1 and the underlying mechanisms.
METHODS: TPC-1 cells were treated with SchA and/or transfected with miR-429 mimic, anti-miR-429 and their corresponding negative controls (NC). Cell viability, proliferation, migration, invasion and cell apoptosis were examined by CCK-8 assay, bromodeoxyuridine, modified two-chamber migration assay, Millicell Hanging Cell Culture and flow cytometry analysis, respectively. The expression of miR-429, p16, Cyclin D1, cyclin-dependent kinases 4 (CDK4), matrix metalloprotein (MMP)-2, MMP-9 and Vimentin was detected by qRT-PCR. All protein expression was examined by western blot.
RESULTS: SchA inhibited cell proliferation, metastasis and induced cell apoptosis. Moreover, SchA negatively regulated miR-429 expression. Treatment with miR-429 mimic and SchA reversed the results led by SchA and NC. Furthermore, the phosphorylation β-catenin, mitogen-activated protein kinase (MEK) and extracellular signal-regulated kinase (ERK) were statistically down-regulated by SchA while co-treatment with miR-429 mimic and SchA led to the opposite trend. Moreover, miR-429 knockdown showed contrary results.
CONCLUSION: SchA inhibits cell proliferation, migration, invasion and inactivates Wnt/β-catenin and MEK/ERK signaling pathways by down regulating miR-429.
The dysregulation of Fbxo4-cyclin D1 axis occurs at high frequency in esophageal squamous cell carcinoma (ESCC), where it promotes ESCC development and progression. However, defining a therapeutic vulnerability that results from this dysregulation has remained elusive. Here we demonstrate that Rb and mTORC1 contribute to Gln-addiction upon the dysregulation of the Fbxo4-cyclin D1 axis, which leads to the reprogramming of cellular metabolism. This reprogramming is characterized by reduced energy production and increased sensitivity of ESCC cells to combined treatment with CB-839 (glutaminase 1 inhibitor) plus metformin/phenformin. Of additional importance, this combined treatment has potent efficacy in ESCC cells with acquired resistance to CDK4/6 inhibitors in vitro and in xenograft tumors. Our findings reveal a molecular basis for cancer therapy through targeting glutaminolysis and mitochondrial respiration in ESCC with dysregulated Fbxo4-cyclin D1 axis as well as cancers resistant to CDK4/6 inhibitors.
Background: Cyclin-dependent kinase-like 1 (CDKL1) is a member of the cell division control protein 2-related serine-threonine protein kinase family. It is known to occur in various malignant tumors, but its role in neuroblastoma (NB) remains unclear.
Methods: We constructed a CDKL1-silenced NB cell strain (SH-SY5Y) and used real-time PCR and western blotting to confirm the silencing. Functional analyses were performed using the MTT, colony-formation, FACS, wound-healing and transwell invasion assays.
Results: The expression of CDKL1 was significantly upregulated in NB tissue as compared to the adjacent normal tissue. CDKL1 knockdown significantly suppressed cell viability and colony formation ability. It also induced cell cycle G0/G1 phase arrest and apoptosis, and suppressed the migration and invasion ability of SH-SY5Y cells. CDKL1 knockdown decreased the CDK4, cyclin D1 and vimentin expression levels, and increased the caspase-3, PARP and E-cadherin expression levels in SH-SY5Y cells.
Conclusions: Our findings suggest that CDKL1 plays an important role in NB cell proliferation, migration and invasion. It might serve as a potential target for NB therapy.
Steele TM, Talbott GC, Sam A, et al.
Obatoclax, a BH3 Mimetic, Enhances Cisplatin-Induced Apoptosis and Decreases the Clonogenicity of Muscle Invasive Bladder Cancer Cells via Mechanisms That Involve the Inhibition of Pro-Survival Molecules as Well as Cell Cycle Regulators.Int J Mol Sci. 2019; 20(6) [
PubMed]
Free Access to Full Article Related Publications
Several studies by our group and others have determined that expression levels of Bcl-2 and/or Bcl-xL, pro-survival molecules which are associated with chemoresistance, are elevated in patients with muscle invasive bladder cancer (MI-BC). The goal of this study was to determine whether combining Obatoclax, a BH3 mimetic which inhibits pro-survival Bcl-2 family members, can improve responses to cisplatin chemotherapy, the standard of care treatment for MI-BC. Three MI-BC cell lines (T24, TCCSuP, 5637) were treated with Obatoclax alone or in combination with cisplatin and/or pre-miR-34a, a molecule which we have previously shown to inhibit MI-BC cell proliferation via decreasing Cdk6 expression. Proliferation, clonogenic, and apoptosis assays confirmed that Obatoclax can decrease cell proliferation and promote apoptosis in a dose-dependent manner. Combination treatment experiments identified Obatoclax + cisplatin as the most effective treatment. Immunoprecipitation and Western analyses indicate that, in addition to being able to inhibit Bcl-2 and Bcl-xL, Obatoclax can also decrease cyclin D1 and Cdk4/6 expression levels. This has not previously been reported. The combined data demonstrate that Obatoclax can inhibit cell proliferation, promote apoptosis, and significantly enhance the effectiveness of cisplatin in MI-BC cells via mechanisms that likely involve the inhibition of both pro-survival molecules and cell cycle regulators.
Adipocytic neoplasms include a diversity of both benign tumors (lipomas) and malignancies (liposarcomas), and each tumor type is characterized by its own unique molecular alterations driving tumorigenesis. Work over the past 30 years has established the diagnostic utility of several of these characteristic molecular alterations (e.g. MDM2 amplification in well- and dedifferentiated liposarcoma, FUS/EWSR1-DDIT3 gene fusions in myxoid liposarcoma, RB1 loss in spindle cell/pleomorphic lipoma). More recent studies have focused on additional molecular alterations which may have therapeutic or prognostic impact. This review will summarize several of the important molecular findings in adipocytic tumors that have been described over the past 10 years.
Thway K
Well-differentiated liposarcoma and dedifferentiated liposarcoma: An updated review.Semin Diagn Pathol. 2019; 36(2):112-121 [
PubMed]
Related Publications
Well-differentiated liposarcoma (WDL)/atypical lipomatous tumor and dedifferentiated liposarcoma (DDL) together comprise the largest subgroup of liposarcomas, and constitute a histologic and behavioral spectrum of one disease. WDL and DDL typically occur in middle-aged to older adults, particularly within the retroperitoneum or extremities. WDL closely resembles mature adipose tissue, but typically shows fibrous septation with variable nuclear atypia and enlargement. WDL does not metastasize, but can dedifferentiate to DDL, which is associated with more aggressive clinical behavior, with a greater propensity for local recurrence and the capacity for metastasis. Although distant metastasis is rarer in DDL compared with other pleomorphic sarcomas, behavior is related to location, with a significantly worse outcome in retroperitoneal tumors. DDL typically has the appearance of undifferentiated pleomorphic or spindle cell sarcoma, and is usually a non-lipogenic sarcoma that is adjacent to WDL, occurs as a recurrence of WDL or which can arise de novo. WDL and DDL share similar background genetic aberrations; both are associated with high-level amplifications in the chromosomal 12q13-15 region, which includes the CDK4 and MDM2 cell cycle oncogenes. In addition, DDL harbor further genetic changes, particularly 6q23 and 1p32 coamplifications. While surgical excision remains the treatment mainstay with limited medical options for patients with aggressive recurrent disease or metastases, novel targeted therapies towards the gene products of chromosome 12 are being evaluated. This review summarizes the pathology of WDL and DDL, discussing morphology, immunohistochemistry, genetics and the differential diagnosis.
BACKGROUND: Use of cyclin D1 (CCND1) gene amplification as a breast cancer biomarker has been hampered by conflicting assessments of the relationship between cyclin D1 protein levels and patient survival. Here, we aimed to clarify its prognostic and treatment predictive potential through comprehensive long-term survival analyses.
METHODS: CCND1 amplification was assessed using SNP arrays from two cohorts of 1965 and 340 patients with matching gene expression array and clinical follow-up data of over 15 years. Kaplan-Meier and multivariable Cox regression analyses were used to determine survival differences between CCND1 amplified vs. non-amplified tumours in clinically relevant patient sets, within PAM50 subtypes and within treatment-specific subgroups. Boxplots and differential gene expression analyses were performed to assess differences between amplified vs. non-amplified tumours within PAM50 subtypes.
RESULTS: When combining both cohorts, worse survival was found for patients with CCND1-amplified tumours in luminal A (HR = 1.68; 95% CI, 1.15-2.46), luminal B (1.37; 1.01-1.86) and ER+/LN-/HER2- (1.66; 1.14-2.41) subgroups. In gene expression analysis, CCND1-amplified luminal A tumours showed increased proliferation (P < 0.001) and decreased progesterone (P = 0.002) levels along with a large overlap in differentially expressed genes when comparing luminal A and B-amplified vs. non-amplified tumours.
CONCLUSIONS: Our results indicate that CCND1 amplification is associated with worse 15-year survival in ER+/LN-/HER2-, luminal A and luminal B patients. Moreover, luminal A CCND1-amplified tumours display gene expression changes consistent with a more aggressive phenotype. These novel findings highlight the potential of CCND1 to identify patients that could benefit from long-term treatment strategies.
BACKGROUND: Chondrosarcoma is a malignant cartilaginous neoplasm of the bone which resistant to radiation therapy and chemotherapy. Cyclin-dependent kinase 4 (CKD4) is highly expressed in human cancer, and palbociclib, the inhibitor of CDK4 has been used clinically under FDA approval for application in cancer therapeutic remedies. However, the level of CDK4 and the treatment possibility in chondrosarcoma require further exploration. Thus, we aim to investigate the level of CDK4 and accompanying therapeutic effects of palbociclib in chondrosarcoma.
METHODS: We used immunohistochemistric analysis to evaluate human CDK4 productions in chondrosarcoma tissues. The inhibitory expression of CDK4 by siRNA or palbociclib on cell proliferation, invasion, migration, apoptosis and cycle arrest of chondrosarcoma were determined by MTT, wound healing, transwell and flow cytometry. CDK4/Rb signaling pathway were determined by western blot and Immunofluorescence assay. The inhibition effect of palbociclib on tumor growth within the bone were determined by bioluminescence imaging in vivo.
RESULTS: CDK4 was found to express significantly in human chondrosarcoma samples. The enhanced levels of CDK4 were interlinked with malignant metastasis and undesirable prognosis of chondrosarcoma patients. CDK4 was also highly expressed in human chondrosarcoma cell lines and its inhibition by specific siRNA and palbociclib lead to a decrease in cell proliferation, accompanied by the phosphorylation of Rb. Furthermore, palbociclib also induced cell cycle arrest in G1 phase and decreased cell migration and invasion via CDK4/Rb signaling pathway. Administration of palbociclib in vivo could reduce tumor burden in chondrosarcoma.
CONCLUSIONS: In summary, these data highlight CDK4 inhibitors, such as palbociclib, as potential promising therapeutics in the treatment of human chondrosarcoma.
Secme M, Kaygusuz O, Eroglu C, et al.
Potential Anticancer Activity of the Parasol Mushroom, Macrolepiota procera (Agaricomycetes), against the A549 Human Lung Cancer Cell Line.Int J Med Mushrooms. 2018; 20(11):1075-1086 [
PubMed]
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Mushrooms comprise an unlimited source of active compounds that have beneficial health effects without known negative side effects and can potentially be used as important therapeutic products against cancer, which is the leading cause of death worldwide. In this study we investigated the cytotoxic, antiproliferative, apoptotic, and anti-invasion effects of Macrolepiota procera, which is valued as an edible and medicinal mushroom, on A549 lung cancer cells. The cytotoxic effect of the M. procera extract was determined by using the XTT method. Total RNA was isolated from cells with TRI Reagent to determine the apoptotic effect of the extract, after which complementary DNA was synthesized. Expression profiles of the target genes were determined by quantitative reverse-transcriptase polymerase chain reaction, and protein changes were determined by using Western blotting. We used the TUNEL assay to evaluate the apoptotic effects of the M. procera extract. Effects of M. procera on cell invasion were investigated by using a Matrigel chamber assay. The half-maximal inhibitory concentration of the M. procera extract was determined to be 2 mg/mL against A549 lung cancer cells at 72 hours. According to our results, expression of Cyclin Dl, CDK4, CDK6, Bcl-2, Akt, and NOXA genes significantly decreased and that of Bax, Caspase-3, Caspase-9, PTEN, PUMA, p21, and p53 increased in cells from the dose group compared with their expression in control cells. According to the results of the TUNEL assay, 28 ± 3.6% of cells were apoptotic in the dose group. The M. procera extract also reduced invasion in A549 cancer cells. The results suggest that M. procera has an antiproliferative effect in a dose- and time-dependent manner.
Xiong Y, Li T, Assani G, et al.
Ribociclib, a selective cyclin D kinase 4/6 inhibitor, inhibits proliferation and induces apoptosis of human cervical cancer in vitro and in vivo.Biomed Pharmacother. 2019; 112:108602 [
PubMed]
Related Publications
Cervical cancer remains one of the main factors leading to tumor-related death worldwide. Many strategies of cancer treatment such as chemotherapy are developed and used nowadays. However, for the cancer chemotherapy resistance, reduction of the limitation of cancer chemotherapy efficacy is one of the aims of several oncology teams. Moreover, the cyclin-dependent kinase 4/6-cyclin D-retinoblastoma protein-E2F pathway is an important mechanism for cell cycle control and its dysregulation is one of the key factors for cancers development including cervical cancer. Ribociclib is one of the selective CDK4/6 inhibitors and is a new therapeutic approach showing promise as a good strategy of therapy in many human cancers. However, there are not the studies regarding the investigation of effects of Ribociclib in cervical cancer yet. In the present study, by western blotting and immunofluorescence assay, we found respectively that CDK4, CDK6 and cyclin D1 are highly expressed and are mostly localized in the nucleus with some localized in the cytoplasm of cervical cancer cell lines. Moreover, Ribociclib induced cell cycle arrest in G0-G1 phase and cell apoptosis, and inhibited C33A cell proliferation in dose - dependent manner following by decreased expression of certain related genes such as CDK4, CDK6, E2F1, P-Rb, and increased Bax expression. In C33A xenografts, Ribociclib inhibited tumor growth associated with decreased expressions of CDK4, CDK6, cyclin D1, Rb and Ki-67, and also significantly increased tumor cell apoptosis. However, we didn't find side effect of Ribociclib concerning heart, liver and kidney perturbation and any Ribociclib anti-tumor effects on HeLa in vitro and in vivo which may be due to Hela cell infection by HPV. Based on our findings, the Rb-E2F pathway can be considered as an important factor in human cervical cancer pathogenesis and as a mechanism of Ribociclib, a potential strategy of treatment for the improvement of new therapeutic measures for the treatment of HPV-negative cervical cancer which application for HPV-positive cervical cancer is desired in further study.
Zhou R, Shi C, Tao W, et al.
Analysis of Mucosal Melanoma Whole-Genome Landscapes Reveals Clinically Relevant Genomic Aberrations.Clin Cancer Res. 2019; 25(12):3548-3560 [
PubMed]
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PURPOSE: Unlike advances in the genomics-driven precision treatment of cutaneous melanomas, the current poor understanding of the molecular basis of mucosal melanomas (MM) has hindered such progress for MM patients. Thus, we sought to characterize the genomic landscape of MM to identify genomic alterations with prognostic and/or therapeutic implications.
EXPERIMENTAL DESIGN: Whole-genome sequencing (WGS) was performed on 65 MM samples, including 63 paired tumor blood samples and 2 matched lymph node metastases, with a further droplet digital PCR-based validation study of an independent MM cohort (
RESULTS: Besides the identification of well-recognized driver mutations of
CONCLUSIONS: Our largest-to-date cohort WGS analysis of MMs defines the genomic landscape of this deadly cancer at unprecedented resolution and identifies genomic aberrations that could facilitate the delivery of precision cancer treatments.
BACKGROUND: Damage-regulated autophagy modulator 2(DRAM2) is associated with autophagy processes. However, the role of DRAM2 in the progression of human neoplasms is still unknown. Here, we show that DRAM2 may act as an oncogenic regulator in non-small cell lung cancer (NSCLC).
METHODS: Tumor specimens from 259 NSCLC patients were collected and analyzed. Transwell migration, cell cycle analysis, MTT and colony formation assays were performed to determine the effect of DRAM2 overexpression and knockdown on NSCLC-cell migration and proliferation. Western blotting confirmed the expression of DRAM2, p53, and the other involved proteins.
RESULTS: DRAM2 was preferentially upregulated in NSCLC tissues and higher expression of DRAM2 in NSCLC correlated with tumor node metastases stage and lymph node metastasis. Additionally, DRAM2 overexpression promoted cell metastasis and proliferation in vitro, while knockdown of DRAM2 expression yielded opposite result. Furthermore, DRAM2 overexpression increased the expression of proteins RAC1, RHOA, RHOC, ROCK1, and decreased RHOB expression, all of which are cell migration factors. DRAM2 overexpression also increased proteins CDK4, CyclinD3, and decreased p27 expression, all of which are cell cycle-related factors. Consistently knocked down DRAM2 had the opposite effect. We also found that DRAM2 expression was negatively correlated to p53 expression. Knockdown of DRAM2 caused an increase of p53 and p21 expression, and overexpression of p53 caused a decrease of DRAM2 expression. Finally, absence of p53 did not influence the function of DRAM2 in NSCLC, but overexpression of p53 repressed its function.
CONCLUSIONS: DRAM2 plays an oncogenic role in NSCLC via regulating p53 expression. Therefore, DRAM2 may act as an oncogene in NSCLC and could serve as a prognostic factor and potential target for NSCLC treatment.
APOBEC3B is a single-stranded DNA cytosine deaminase with beneficial innate antiviral functions. However, misregulated APOBEC3B can also be detrimental by inflicting APOBEC signature C-to-T and C-to-G mutations in genomic DNA of multiple cancer types. Polyomavirus and papillomavirus oncoproteins induce APOBEC3B overexpression, perhaps to their own benefit, but little is known about the cellular mechanisms hijacked by these viruses to do so. Here we investigate the molecular mechanism of APOBEC3B upregulation by the polyomavirus large T antigen. First, we demonstrate that the upregulated APOBEC3B enzyme is strongly nuclear and partially localized to virus replication centers. Second, truncated T antigen (truncT) is sufficient for APOBEC3B upregulation, and the RB-interacting motif (LXCXE), but not the p53-binding domain, is required. Third, genetic knockdown of RB1 alone or in combination with RBL1 and/or RBL2 is insufficient to suppress truncT-mediated induction of
Esophageal adenocarcinoma (EAC) is a poor-prognosis cancer type with rapidly rising incidence. Understanding of the genetic events driving EAC development is limited, and there are few molecular biomarkers for prognostication or therapeutics. Using a cohort of 551 genomically characterized EACs with matched RNA sequencing data, we discovered 77 EAC driver genes and 21 noncoding driver elements. We identified a mean of 4.4 driver events per tumor, which were derived more commonly from mutations than copy number alterations, and compared the prevelence of these mutations to the exome-wide mutational excess calculated using non-synonymous to synonymous mutation ratios (dN/dS). We observed mutual exclusivity or co-occurrence of events within and between several dysregulated EAC pathways, a result suggestive of strong functional relationships. Indicators of poor prognosis (SMAD4 and GATA4) were verified in independent cohorts with significant predictive value. Over 50% of EACs contained sensitizing events for CDK4 and CDK6 inhibitors, which were highly correlated with clinically relevant sensitivity in a panel of EAC cell lines and organoids.
Inactivating mutations in SMARCA4 (BRG1), a key SWI/SNF chromatin remodelling gene, underlie small cell carcinoma of the ovary, hypercalcemic type (SCCOHT). To reveal its druggable vulnerabilities, we perform kinase-focused RNAi screens and uncover that SMARCA4-deficient SCCOHT cells are highly sensitive to the inhibition of cyclin-dependent kinase 4/6 (CDK4/6). SMARCA4 loss causes profound downregulation of cyclin D1, which limits CDK4/6 kinase activity in SCCOHT cells and leads to in vitro and in vivo susceptibility to CDK4/6 inhibitors. SCCOHT patient tumors are deficient in cyclin D1 yet retain the retinoblastoma-proficient/p16
Tumor suppressor SMARCA4 (BRG1), a key SWI/SNF chromatin remodeling gene, is frequently inactivated in cancers and is not directly druggable. We recently uncovered that SMARCA4 loss in an ovarian cancer subtype causes cyclin D1 deficiency leading to susceptibility to CDK4/6 inhibition. Here, we show that this vulnerability is conserved in non-small cell lung cancer (NSCLC), where SMARCA4 loss also results in reduced cyclin D1 expression and selective sensitivity to CDK4/6 inhibitors. In addition, SMARCA2, another SWI/SNF subunit lost in a subset of NSCLCs, also regulates cyclin D1 and drug response when SMARCA4 is absent. Mechanistically, SMARCA4/2 loss reduces cyclin D1 expression by a combination of restricting CCND1 chromatin accessibility and suppressing c-Jun, a transcription activator of CCND1. Furthermore, SMARCA4 loss is synthetic lethal with CDK4/6 inhibition both in vitro and in vivo, suggesting that FDA-approved CDK4/6 inhibitors could be effective to treat this significant subgroup of NSCLCs.
Knudsen ES, Kumarasamy V, Ruiz A, et al.
Cell cycle plasticity driven by MTOR signaling: integral resistance to CDK4/6 inhibition in patient-derived models of pancreatic cancer.Oncogene. 2019; 38(18):3355-3370 [
PubMed]
Free Access to Full Article Related Publications
Pancreatic ductal adenocarcinoma (PDAC), like many KRAS-driven tumors, preferentially loses CDKN2A that encodes an endogenous CDK4/6 inhibitor to bypass the RB-mediated cell cycle suppression. Analysis of a panel of patient-derived cell lines and matched xenografts indicated that many pancreatic cancers have intrinsic resistance to CDK4/6 inhibition that is not due to any established mechanism or published biomarker. Rather, there is a KRAS-dependent rapid adaptive response that leads to the upregulation of cyclin proteins, which participate in functional complexes to mediate resistance. In vivo, the degree of response is associated with the suppression of a gene expression signature that is strongly prognostic in pancreatic cancer. Resistance is associated with an adaptive gene expression signature that is common to multiple kinase inhibitors, but is attenuated with MTOR inhibitors. Combination treatment with MTOR and CDK4/6 inhibitors had potent activity across a large number of patient-derived models of PDAC underscoring the potential clinical efficacy.
Colorectal cancer (CRC) is the second most common cause of cancer-related death in the world, but early diagnosis ameliorates the survival of CRC. This report aimed to identify molecular biomarker signatures in CRC. We analyzed two microarray datasets (GSE35279 and GSE21815) from the Gene Expression Omnibus (GEO) to identify mutual differentially expressed genes (DEGs). We integrated DEGs with protein⁻protein interaction and transcriptional/post-transcriptional regulatory networks to identify reporter signaling and regulatory molecules; utilized functional overrepresentation and pathway enrichment analyses to elucidate their roles in biological processes and molecular pathways; performed survival analyses to evaluate their prognostic performance; and applied drug repositioning analyses through Connectivity Map (CMap) and geneXpharma tools to hypothesize possible drug candidates targeting reporter molecules. A total of 727 upregulated and 99 downregulated DEGs were detected. The PI3K/Akt signaling, Wnt signaling, extracellular matrix (ECM) interaction, and cell cycle were identified as significantly enriched pathways. Ten hub proteins (ADNP, CCND1, CD44, CDK4, CEBPB, CENPA, CENPH, CENPN, MYC, and RFC2), 10 transcription factors (ETS1, ESR1, GATA1, GATA2, GATA3, AR, YBX1, FOXP3, E2F4, and PRDM14) and two microRNAs (miRNAs) (miR-193b-3p and miR-615-3p) were detected as reporter molecules. The survival analyses through Kaplan⁻Meier curves indicated remarkable performance of reporter molecules in the estimation of survival probability in CRC patients. In addition, several drug candidates including anti-neoplastic and immunomodulating agents were repositioned. This study presents biomarker signatures at protein and RNA levels with prognostic capability in CRC. We think that the molecular signatures and candidate drugs presented in this study might be useful in future studies indenting the development of accurate diagnostic and/or prognostic biomarker screens and efficient therapeutic strategies in CRC.
Chiang SR, Lin CS, Lin HH, et al.
Bergapten induces G1 arrest of non‑small cell lung cancer cells, associated with the p53‑mediated cascade.Mol Med Rep. 2019; 19(3):1972-1978 [
PubMed]
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The principal subtype of lung cancer, non‑small cell lung cancer (NSCLC) is a life‑threatening malignancy that causes high mortality rates. Bergapten (5‑methoxypsoralen) has been identified to possess anticancer activity against a number of carcinomas. In the present study, the effects of bergapten on NSCLC cells were investigated. The cell viability was determined by MTT assay. Cell cycle distribution was analyzed using flow cytometry. Protein expression and kinase cascade were demonstrated using western blot analysis. The results demonstrated that treatment with bergapten (50 µM for 48 h) inhibited the viability of A549 and NCI‑H460 NSCLC cells to 79.1±2.8% and 74.5±3.1%, respectively, compared with the controls. It was identified that bergapten induced G1 phase accumulation in A549 and NCI‑H460 cells between ~58 and 75% (P<0.01). In addition, bergapten significantly increased the sub‑G1 phase ratio to ~9% (P<0.05) in the two cell types. Further investigation demonstrated that bergapten upregulated the expression of cellular tumor antigen p53 (p53) and its downstream proteins cyclin‑dependent kinase inhibitor 1 and cyclin‑dependent kinase inhibitor 1B, whereas, it downregulated the expression of cyclin D1 and CDK4. Overall, these results suggested that bergapten may inhibit cell viability and trigger G1 arrest and apoptosis in A549 and NCI‑H460 cells, which may be attributed to the activation of p53‑mediated cascades. Therefore, bergapten may be beneficial for NSCLC treatment.
Zhang Z, Liu X, Xu H, et al.
LINC01170 promotes the progression of endometrial carcinoma by activating the AKT pathway.J BUON. 2018 Nov-Dec; 23(6):1745-1752 [
PubMed]
Related Publications
PURPOSE: To investigate the function of LINC01170 in the progression of endometrial carcinoma and its underlying mechanism.
METHODS: The expression profiles and prognostic data of endometrial carcinoma were downloaded by GDC (genomic data commons) analysis tools. Differentially expressed long noncoding (lnc)RNAs were analyzed by the edgeR (empirical analysis of digital gene expression data in R) package. LncRNAs that were related to prognosis of endometrial carcinoma were calculated by the survival function. Moreover, the PHEAT map package was introduced to edit heatmaps of differentially expressed lncRNAs. Human endometrial carcinoma cell lines (Ishikawa, ECC and HEC-IA) were cultured. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expressions of lncRNAs and related genes. Cell proliferation was detected by MTT, and cell cycle and apoptosis were detected by flow cytometry. Additionally, Western blot was used to detect protein expressions of relative genes.
RESULTS: Results showed that LINC01170 was a non-coding RNA. LINC01170 was overexpressed in endometrial carcinoma, which was a risk factor for prognosis of this disease. LINC01170 expressions in carcinoma and para-cancerous tissues of 50 patients with endometrial carcinoma were detected by qRT-PCR and found that the expression level of LINC01170 in endometrial carcinoma was remarkably increased than that of para-cancerous tissues. Moreover, the expression level of LINC01170 in advanced endometrial carcinoma was remarkably higher than that of early-stage disease. After interfering with LINC01170, the proliferation of both the Ishikawa and HEC-1A cells were remarkably decreased, and cell cycle was arrested at the G0/G1 phase. Meanwhile, apoptosis results showed a remarkable apoptosis rate after interfering with LINC01170. Western blot results also demonstrated the decreased activity of AKT pathway and phosphorylated expression of AKT protein after LINC01170 knockdown. In addition, expressions of CDK2, CDK4 and Bcl-2 were decreased after LINC01170 knockdown.
CONCLUSIONS: LINC01170 promotes the progression of endometrial carcinoma through stimulating proliferation, cell cycle transition and inhibiting apoptosis of endometrial carcinoma cells via AKT pathway.
BACKGROUND: Several studies have investigated the molecular drivers and therapeutic targets in adult soft tissue sarcomas. However, such studies are limited by the genomic heterogeneity and rarity of sarcomas, particularly in those with complex and unbalanced karyotypes. Additional biomarkers are needed across sarcoma types to improve therapeutic strategies. To investigate the molecular characteristics of complex karyotype sarcomas (CKSs) for therapeutic targets, we performed genomic profiling.
RESULTS: The mutational landscape showed that TP53, ATRX, and PTEN genes were highly mutated. CKS samples were categorized into three groups based on copy number variations that were associated with CDK4 and RB1 signatures. Integrated analysis of genomic and transcriptomic data revealed several pathways related to PDGFR, which could be a strategic target for anti-sarcoma therapy.
CONCLUSIONS: This study provides a detailed molecular classification of CKSs and proposes several therapeutic targets. Targeted or combinational therapies for treating CKS should be considered before chemotherapy.
The present study investigated the expression and potential influence of SHC SH2 domain‑binding protein 1 (SHCBP1) in gastric cancer (GC) cells. SHCBP1 is closely related to cell proliferation and cell cycle progression, but its role in GC remains unclear. The TCGA database revealed that SHCBP1 is highly expressed in GC tissues. Furthermore, SHCBP1 was revealed to be highly expressed in GC cell lines MGC‑803 and SGC‑7901 cells, and downregulation of SHCBP1 significantly inhibited GC cell proliferation. Furthermore, SHCBP1 expression promoted cell cycle progression and inhibition of apoptosis. Since the CDK4, cyclin D1 and caspase family proteins play important roles in cell cycle and apoptosis regulation, it was examined whether there was an association between SHCBP1 and these signaling pathways in GC. Our results revealed that SHCBP1 promoted cell cycle progression by regulating the CDK4‑cyclin D1 cascade and suppressed caspase‑3, caspase PARP‑dependent apoptotic pathways. Cell invasion and metastasis experiments also revealed that SHCBP1 promoted tumor growth and invasiveness. These tumor‑promoting functions of SHCBP1 may provide a potential molecular basis for the diagnosis and targeted therapy of GC.
Zhang X, Yang X, Zhu S, et al.
Radiosensitization of esophageal carcinoma cells by knockdown of HMGB1 expression.Oncol Rep. 2019; 41(3):1960-1970 [
PubMed]
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Radiotherapy (RT) is a traditional and important treatment for carcinoma of the esophagus along with surgery and chemotherapy. High mobility group box 1 (HMGB1) plays a crucial part in inhibiting the apoptosis of cancer cells after irradiation treatment. The present study, was designed to analyze the function of HMGB1 in esophageal cancer progression and elucidate the effects of HMGB1 on the radiosensitivity of human esophageal cancer cell lines. In the present study, an immunohistochemical evaluation of HMGB1 was performed on 77 biopsies, and the results revealed that HMGB1 overexpression was positively correlated with gross tumor volume (GTV), tumor‑node‑metastasis (TNM) stage, T classification, distant metastasis, and relapse and negatively correlated with patient survival rates, suggesting that HMGB1 acts as a key factor in the development of esophageal cancer. An shRNA targeting HMGB1 was designed for the knockdown of HMGB1 in ECA109 and TE13 cells, and the transfection efficiency of the shRNA was assessed using quantitative real‑time reverse transcription polymerase chain reaction and western blot analysis. CCK‑8 and clonogenic assays were used to analyze the effect of HMGB1 on the proliferation and radiosensitivity, respectively, of esophageal cancer cells in vitro. The influence of HMGB1 on radiation‑induced changes in the migration, invasion, and cell cycle as well as apoptosis of tumor cells was examined by wound‑healing and Transwell assays and flow cytometry, respectively. In addition, xenograft tumor models were constructed to observe the effect of HMGB1 on tumor growth in vivo. The results of the study in vitro revealed that the proliferation of the HMGB1‑shRNA group decreased after irradiation, and the radiation treatment reduced the tumor volume of the xenograft model which was more marked in HMGB1‑shRNA group. Moreover, HMGB1 was involved in the phosphorylation of H2AX after irradiation, and HMGB1 knockdown blocked the cell cycle in the G0/G1 phase and increased apoptosis. HMGB1 deficiency was also correlated with the upregulation of p16, Bax and caspase‑9 and the downregulation of MMP‑2, MMP‑9, cyclin D1, CDK4, γH2AX and Bcl‑2. These data indicated that the overexpression of HMGB1 prior to treatment was correlated with poor clinical outcome in esophageal carcinoma and that knockdown HMGB1 expression in human esophageal cancer cell lines increased their radiosensitivity by allowing the induction of apoptosis and G0/G1 arrest after exposure to radiation.
Tan ZB, Fan HJ, Wu YT, et al.
Rheum palmatum extract exerts anti-hepatocellular carcinoma effects by inhibiting signal transducer and activator of transcription 3 signaling.J Ethnopharmacol. 2019; 232:62-72 [
PubMed]
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ETHNOPHARMACOLOGICAL RELEVANCE: Hepatocellular carcinoma (HCC) is among the most common malignancies. Signal transducer and activator of transcription 3 (STAT3), with abnormal expression and constitutive activation, has been reported to promote proliferation, metastasis, survival and angiogenesis of HCC cells. Rheum palmatum (RP), a traditional Chinese medicinal herb, exhibited tumor-suppressing effects in multiple human cancers, but its potential functions in HCC remain unexplored.
AIM OF THE STUDY: This study aimed to examine the involvement of STAT3 signaling in the anti-HCC effects of RP extract.
MATERIALS AND METHODS: SMMC-7721 and HepG2 HCC cell lines were treated with RP extract for 24 h, and then viability, migration, and invasion of HCC cells and angiogenesis of human umbilical vein endothelial cells (HUVECs) were analyzed using MTS, wound-healing, Transwell invasion and tube formation assays, respectively. Western blotting and immunohistochemistry (IHC) were used to examine the activation of key molecules in STAT3 signaling, including STAT3, JAK2, and Src. Additionally, we explored the in vivo antitumor effects of RP extract in a xenograft tumor nude mouse model of HCC.
RESULTS: The result showed that RP extract reduced viability, migration, and invasion of SMMC-7721 and HepG2 cells and angiogenesis of HUVECs. It suppressed the phosphorylation of STAT3 and its upstream kinases including JAK2 and Src. In addition, RP extract treatment downregulated STAT3 target genes, including survivin, Bcl-xL, Mcl-1, Bcl-2, MMP-2, MMP-9, Cyclin D1, CDK4, c-Myc, and VEGF-C. Furthermore, RP extract suppressed the xenograft tumor growth and activation of STAT3 in xenograft tumor mice.
CONCLUSION: Collectively, the results showed that RP extract prevented HCC progression by inhibiting STAT3, and might be useful for the treatment of HCC.
Yang Y, Cui H, Wang X
Downregulation of EIF5A2 by miR-221-3p inhibits cell proliferation, promotes cell cycle arrest and apoptosis in medulloblastoma cells.Biosci Biotechnol Biochem. 2019; 83(3):400-408 [
PubMed]
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Recently, miR-221-3p expression has been reported to be down-regulated in medulloblastoma (MB), but its functional effects remains unclear. In this study, quantitative real-time PCR (qRT-PCR) revealed significantly decreased miR-221-3p in MB cell lines. Transfection of miR-221-3p mimics reduced, or inhibitor increased cell proliferation in MB cells using MTT assay. Flow cytometry analysis indicated miR-221-3p overexpression promoted, while knockdown alleviated G0/G1 arrest and apoptosis. Luciferase reporter assay confirmed miR-221-3p directly targets the EIF5A2 gene. Moreover, restoration of EIF5A2 in the miR-221-3p-overexpressing DAOY cells significantly alleviated the suppressive effects of miR-221-3p on cell proliferation, cell cycle and apoptosis. Furthermore, miR-221-3p overexpression decreased CDK4, Cyclin D1 and Bcl-2 and increased Bad expression, which was reversed by EIF5A2 overexpression. These results uncovered the tumor suppressive role of miR-221-3p in MB cell proliferation at least in part via targeting EIF5A2, suggesting that miR-221-3p might be a potential candidate target for diagnosis and therapeutics of MB.
Zhang X, Yu J, Zhao C, et al.
MiR-181b-5p modulates chemosensitivity of glioma cells to temozolomide by targeting Bcl-2.Biomed Pharmacother. 2019; 109:2192-2202 [
PubMed]
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Chemotherapy is the main postsurgical and adjuvant therapy for glioma, and intrinsic or acquired temozolomide (TMZ) resistance may result in poor prognosis. The miR-181 family was discovered to play an important role in regulating biological functions in glioma, and miR-181b is less expressed in human gliomas as a tumor-suppressive miRNA. The aim of this study was to explore the molecular mechanism of miR-181b-5p and its target gene on modulating TMZ chemosensitivity in glioma cells. The enhanced chemosensitivity effect of miR-181b-5p to TMZ in glioma cells U87MG and U251 was detected by MTT method. Dual luciferase reporter assay, quantitative real-time PCR (qRT-PCR) and Western blotting were performed to demonstrate that miR-181b-5p directly targets Bcl-2 to reduce the expression. Transwell and flow cytometry assays showed that combination of miR-181b-5p and TMZ exerted stronger effects on inhibiting U87MG cells proliferation, migration and invasion as well as promoting apoptosis and S phase arrest than miR-181b-5p and TMZ alone. The same tendency was observed in the upregulation of apoptosis-related protein Bax and downregulation of cycle-related proteins CyclinD1 and CDK4. In vivo experiments indicated that miR-181b-5p could enhance the tumor-suppressive effect of TMZ. In conclusion, our findings indicate that upregulation of miR-181b-5p targets Bcl-2 directly and may function as an important modifier to sensitize glioma cells to TMZ.