Gene Summary

Gene:CD44; CD44 molecule (Indian blood group)
Aliases: IN, LHR, MC56, MDU2, MDU3, MIC4, Pgp1, CDW44, CSPG8, HCELL, HUTCH-I, ECMR-III
Summary:The protein encoded by this gene is a cell-surface glycoprotein involved in cell-cell interactions, cell adhesion and migration. It is a receptor for hyaluronic acid (HA) and can also interact with other ligands, such as osteopontin, collagens, and matrix metalloproteinases (MMPs). This protein participates in a wide variety of cellular functions including lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis. Transcripts for this gene undergo complex alternative splicing that results in many functionally distinct isoforms, however, the full length nature of some of these variants has not been determined. Alternative splicing is the basis for the structural and functional diversity of this protein, and may be related to tumor metastasis. [provided by RefSeq, Jul 2008]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:CD44 antigen
Source:NCBIAccessed: 31 August, 2019


What does this gene/protein do?
Show (39)
Pathways:What pathways are this gene/protein implicaed in?
Show (5)

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.

Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (7)

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: CD44 (cancer-related)

Li Z, Tan H, Zhao W, et al.
Integrative analysis of DNA methylation and gene expression profiles identifies MIR4435-2HG as an oncogenic lncRNA for glioma progression.
Gene. 2019; 715:144012 [PubMed] Related Publications
Long noncoding RNAs (lncRNAs) have been shown to play an important role in tumor biogenesis and prognosis. The glioma is a grade classified cancer, however, we still lack the knowledge on their function during glioma progression. While previous studies have shown how lncRNAs regulate protein-coding gene epigenetically, it is still unclear how lncRNAs are regulated epigenetically. In this study, we firstly analyzed the RNA-seq data systematically across grades II, IV, and IV of glioma samples. We identified 60 lncRNAs that are significantly differentially expressed over disease progression (DElncRNA), including well-known PVT1, HOTAIR, H19 and rarely studied CARD8-AS, MIR4435-2HG. Secondly, by integrating HM450K methylation microarray data, we demonstrated that some of the lncRNAs are epigenetically regulated by methylation. Thirdly, we developed a DESeq2-GSEA-ceRNA-survival analysis strategy to investigate their functions. Particularly, MIR4435-2HG is highly expressed in high-grade glioma and may have an impact on EMT and TNFα signaling pathway by functioning as a miRNA sponge of miR-125a-5p and miR-125b-5p to increase the expression of CD44. Our results revealed the dynamic expression of lncRNAs in glioma progression and their epigenetic regulation mechanism.

Sai E, Miwa Y, Takeyama R, et al.
Identification of candidates for driver oncogenes in scirrhous-type gastric cancer cell lines.
Cancer Sci. 2019; 110(8):2643-2651 [PubMed] Free Access to Full Article Related Publications
Scirrhous-type gastric cancer (SGC) is one of the most intractable cancer subtypes in humans, and its therapeutic targets have been rarely identified to date. Exploration of somatic mutations in the SGC genome with the next-generation sequencers has been hampered by markedly increased fibrous tissues. Thus, SGC cell lines may be useful resources for searching for novel oncogenes. Here we have conducted whole exome sequencing and RNA sequencing on 2 SGC cell lines, OCUM-8 and OCUM-9. Interestingly, most of the mutations thus identified have not been reported. In OCUM-8 cells, a novel CD44-IGF1R fusion gene is discovered, the protein product of which ligates the amino-terminus of CD44 to the transmembrane and tyrosine-kinase domains of IGF1R. Furthermore, both CD44 and IGF1R are markedly amplified in the OCUM-8 genome and abundantly expressed. CD44-IGF1R has a transforming ability, and the suppression of its kinase activity leads to rapid cell death of OCUM-8. To the best of our knowledge, this is the first report describing the transforming activity of IGF1R fusion genes. However, OCUM-9 seems to possess multiple oncogenic events in its genome. In particular, a novel BORCS5-ETV6 fusion gene is identified in the OCUM-9 genome. BORCS5-ETV6 possesses oncogenic activity, and suppression of its message partially inhibits cell growth. Prevalence of these novel fusion genes among SGC awaits further investigation, but we validate the significance of cell lines as appropriate reagents for detailed genomic analyses of SGC.

Hero T, Bühler H, Kouam PN, et al.
The Triple-negative Breast Cancer Cell Line MDA-MB 231 Is Specifically Inhibited by the Ionophore Salinomycin.
Anticancer Res. 2019; 39(6):2821-2827 [PubMed] Related Publications
BACKGROUND/AIM: Tumour cells of the profile CD44
MATERIALS AND METHODS: We analysed two cell lines: i) triple-negative MDA-MB 231 breast cancer cells and ii) a cytokeratin 18-transfected, re-differentiated subclone of the MDA-MB 231 cell line. The viability was determined using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test, and the migration was determined using 24-h videography. The expression of oestrogen receptor was determined using immunohistochemistry.
RESULTS: Salinomycin reduces all migration parameters in MDA-MB 231 cells. A significant correlation was found between increasing salinomycin concentrations and loss of cell viability, which was significantly less noticeable in the transfected control cells.
CONCLUSION: With salinomycin there is a specific inhibition of MDA-MB 231 cells. Since MDA-MB 231 has over 90% cells with the profile CD44

Chen TW, Yin FF, Yuan YM, et al.
CHML promotes liver cancer metastasis by facilitating Rab14 recycle.
Nat Commun. 2019; 10(1):2510 [PubMed] Free Access to Full Article Related Publications
Metastasis-associated recurrence is the major cause of poor prognosis in hepatocellular carcinoma (HCC), however, the underlying mechanisms remain largely elusive. In this study, we report that expression of choroideremia-like (CHML) is increased in HCC, associated with poor survival, early recurrence and more satellite nodules in HCC patients. CHML promotes migration, invasion and metastasis of HCC cells, in a Rab14-dependent manner. Mechanism study reveals that CHML facilitates constant recycling of Rab14 by escorting Rab14 to the membrane. Furthermore, we identify several metastasis regulators as cargoes carried by Rab14-positive vesicles, including Mucin13 and CD44, which may contribute to metastasis-promoting effects of CHML. Altogether, our data establish CHML as a potential promoter of HCC metastasis, and the CHML-Rab14 axis may be a promising therapeutic target for HCC.

Mikami E, Kudo M, Ohashi R, et al.
Toll‑like receptor 4 plays a tumor‑suppressive role in cutaneous squamous cell carcinoma.
Int J Oncol. 2019; 54(6):2179-2188 [PubMed] Related Publications
Toll‑like receptor 4 (TLR4), a key regulator of the innate immune system, is expressed not only in immune cells, but also in a number of cancer cells. A biological role for TLR4 in cutaneous squamous cell carcinoma (SCC), however, is unclear. In this study, we first examined TLR4 expression and localization in cases of SCC, actinic keratosis (AK) and Bowen's disease (BD) by immunohistochemistry. TLR4 expression was significantly higher in the SCC than in the AK or BD tissues. We then determined the TLR4 expression level in vivo, in 3 histological subtypes of SCC. TLR4 expression in poorly differentiated SCC was significantly lower compared with that of the moderately and well‑differentiated type. In addition, the CD44 immunoreactivity tended to be high in the cell membrane of poorly differentiated SCC. Of note, poorly differentiated SCC is a risk factor of unfavorable outcomes in affected patients. We then assessed the biological role of TLR4 in HSC‑1 and HSC‑5 SCC cells and HaCaT human keratinocytes. TLR4 knockdown by transfection with siRNA accelerated HSC‑1 and HaCaT cell migration and invasion compared to the control siRNA‑transfected cells. TLR4 knockdown resulted in an increased CD44 expression and in an enhanced filopodia protrusion formation, particularly in HSC‑1. On the whole, these results suggest that a reduced TLR4 expression enhances the malignant features in SCC cases and cultured SCC cell lines. TLR4 may thus play an anti‑tumor role in cutaneous SCC.

Kim SL, Choi HS, Kim JH, et al.
Dihydrotanshinone-Induced NOX5 Activation Inhibits Breast Cancer Stem Cell through the ROS/Stat3 Signaling Pathway.
Oxid Med Cell Longev. 2019; 2019:9296439 [PubMed] Free Access to Full Article Related Publications
Cancer stem cells (CSCs) are known to mediate metastasis and recurrence and are therefore a promising therapeutic target. In this study, we found that dihydrotanshinone (DHTS) inhibits CSC formation. DHTS inhibited mammosphere formation in a dose-dependent manner and showed significant tumor growth inhibition in a xenograft model. This compound reduced the CD44

Wu D, Yu X, Wang J, et al.
Ovarian Cancer Stem Cells with High ROR1 Expression Serve as a New Prophylactic Vaccine for Ovarian Cancer.
J Immunol Res. 2019; 2019:9394615 [PubMed] Free Access to Full Article Related Publications
Tumor vaccines offer a number of advantages for cancer treatment. In the study, the vaccination with cancer stem cells (CSCs) with high expression of the type I receptor tyrosine kinase-like orphan receptor (ROR1) was evaluated in a murine model for the vaccine's immunogenicity and protective efficacy against epithelial ovarian carcinoma (EOC). CD117

Ji M, Liu L, Hou Y, Li B
1α,25‑Dihydroxyvitamin D3 restrains stem cell‑like properties of ovarian cancer cells by enhancing vitamin D receptor and suppressing CD44.
Oncol Rep. 2019; 41(6):3393-3403 [PubMed] Related Publications
Scientific evidence linking vitamin D with various cancer types is growing, but the effects of vitamin D on ovarian cancer stem cell‑like cells (CSCs) are largely unknown. The present study aimed to examine whether vitamin D was able to restrain the stemness of ovarian cancer. A side population (SP) from malignant ovarian surface epithelial cells was identified as CSCs, in vitro and in vivo. Furthermore, 1α,25‑dihydroxyvitamin D3 [1α,25(OH)2D3] treatment inhibited the self‑renewal capacity of SP cells by decreasing the sphere formation rate and by suppressing the mRNA expression levels of cluster of differentiation CD44, NANOG, OCT4, SOX2, Krüppel‑like factor 4 and adenosine triphosphate binding cassette subfamily G member 2. Additionally, 1α,25(OH)2D3 treatment decreased the expression of Cyclin D1, whereas it increased the expression of β‑catenin and vitamin D receptor (VDR). Notably, immunofluorescence staining verified that 1α,25(OH)2D3 promoted the expression of β‑catenin in the cytoplasm. Furthermore, vitamin D3 delayed the onset of tumor formation derived from injection of ovarian CSCs to nude mice, by reducing CD44 and enhancing β‑catenin expressions in vivo. In conclusion, 1α,25(OH)2D3 restrains the stem cell‑like properties of ovarian cancer cells by enhancing the expression of VDR, by promoting the expression of β‑catenin in the cytoplasm, and by suppressing the expression of CD44. These findings provide a novel insight into the functions of vitamin D in diminishing the stemness of cancer CSCs.

Koh YW, Han JH, Haam S, Jung J
ALDH1 expression correlates with an epithelial-like phenotype and favorable prognosis in lung adenocarcinoma: a study based on immunohistochemistry and mRNA expression data.
J Cancer Res Clin Oncol. 2019; 145(6):1427-1436 [PubMed] Related Publications
PURPOSE: Cancer stem cells (CSC) and epithelial-mesenchymal transition (EMT) pathways are crucial for cancer progression. However, synergistic interactions between CSC and EMT are not clear in non-small cell lung cancer (NSCLC). The objective of this study was to investigate CSC markers such as CD44, NANOG, and ALDH1 expression and its correlation with EMT markers in NSCLC patients. Its association with survival was also determined.
METHODS: CD44, NANOG, and ALDH1 protein expression was evaluated in 267 resected NSCLC and its correlation with e-cadherin, β-catenin, p120 catenin, vimentin, SNAIL, and TWIST expressions was determined based on immunohistochemical and mRNA expression data from The Cancer Genome Atlas (TCGA) database. Survival analyses also were performed based on immunohistochemistry and mRNA expression data from Gene Expression Omnibus dataset.
RESULTS: ALDH1 expression in lung adenocarcinoma was positively correlated with the epithelial-like phenotype, low vimentin and low TWIST in immunohistochemical and mRNA expression data. NANOG and ALDH1 expressions measured by immunohistochemical and mRNA expression profiling data of adenocarcinomas were associated with a favorable prognosis. ALDH1 was an independent favorable prognostic marker for overall survival or recurrence-free survival in adenocarcinoma (P = 0.026 and P = 0.033, respectively). The epithelial-like phenotype expressing P120-catenin and beta-catenin was associated with a favorable prognosis; however, the TWIST-expressing mesenchymal-like phenotype was correlated with an unfavorable prognosis.
CONCLUSIONS: NANOG and ALDH1 protein or mRNA expression showed improved prognosis in adenocarcinoma alone. ALDH1 expression correlated with an epithelial-like phenotype.

Kröger C, Afeyan A, Mraz J, et al.
Acquisition of a hybrid E/M state is essential for tumorigenicity of basal breast cancer cells.
Proc Natl Acad Sci U S A. 2019; 116(15):7353-7362 [PubMed] Free Access to Full Article Related Publications
Carcinoma cells residing in an intermediate phenotypic state along the epithelial-mesenchymal (E-M) spectrum are associated with malignant phenotypes, such as invasiveness, tumor-initiating ability, and metastatic dissemination. Using the recently described CD104

Zhang Q, Huang H, Liu A, et al.
Cell division cycle 20 (CDC20) drives prostate cancer progression via stabilization of β-catenin in cancer stem-like cells.
EBioMedicine. 2019; 42:397-407 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Cell division cycle 20 (CDC20) is frequently overexpressed in malignant tumours and involved in the differentiation process of hematopoietic stem cells. However, the role of CDC20 in prostate cancer stem-like cells (CSCs) remains poorly understood.
METHODS: The expression of CDC20, CD44, β-catenin were examined in prostate cancer specimens by immunohistochemistry assay, the role of CDC20 on the stem-like properties of prostate CSCs was accessed by real-time quantitive PCR, spheroid formation, in vitro and in vivo limiting dilution assay.
FINDING: CDC20 was associated with malignant progression of prostate cancer, the patients with both high expression CDC20 and CD44 or β-catenin were associated with more aggressive clinicopathological features and poor prognosis. CDC20 was usually enriched in CD44
INTERPRETATION: Our results indicated that CDC20 maintains the self-renewal ability of CD44

Afshar E, Hashemi-Arabi M, Salami S, et al.
Screening of acetaminophen-induced alterations in epithelial-to-mesenchymal transition-related expression of microRNAs in a model of stem-like triple-negative breast cancer cells: The possible functional impacts.
Gene. 2019; 702:46-55 [PubMed] Related Publications
Current protocols for therapy inefficiently targets triple negative breast cancer and barely eradicate cancer stem cells. Elucidation of the pleiotropic effect of clinically proven therapeutics on cancer cells shed light on novel application of old friends. The pleiotropic effect of acetaminophen (APAP) on breast cancer was previously reported. In a cell model of triple negative breast cancer with stem-like CD44

Wang Z, Sun H, Provaznik J, et al.
Pancreatic cancer-initiating cell exosome message transfer into noncancer-initiating cells: the importance of CD44v6 in reprogramming.
J Exp Clin Cancer Res. 2019; 38(1):132 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Cancer-initiating cell (CIC) exosomes (CIC-TEX) are suggested reprogramming Non-CIC. Mode of message transfer and engagement of CIC-markers being disputed, we elaborated the impact of CD44v6 and Tspan8 on the response of Non-CIC.
METHODS: Non-metastasizing CD44v6- and Tspan8-knockdown (kd) pancreatic cancer cells served as Non-CIC. CIC-TEX coculture-induced changes were evaluated by deep-sequencing and functional assays. Tumor progression was surveyed during in vivo CIC-TEX treatment.
RESULTS: Deep-sequencing of CIC-TEX-cocultured CD44v6kd-Non-CIC revealed pronounced mRNA changes in signaling, transport, transcription and translation; altered miRNA affected metabolism, signaling and transcription. CIC-TEX coculture-induced changes in Tspan8kd-Non-CIC mostly relied on CIC-TEX-Tspan8 being required for targeting. CIC-TEX transfer supported apoptosis resistance and significantly promoted epithelial mesenchymal transition, migration, invasion and (lymph)angiogenesis of the kd Non-CIC in vitro and in vivo, deep-sequencing allowing individual mRNA and miRNA assignment to altered functions. Importantly, CIC-TEX act as a hub, initiated by CD44v6-dependent RTK, GPCR and integrin activation and involving CD44v6-assisted transcription and RNA processing. Accordingly, a kinase inhibitor hampered CIC-TEX-fostered tumor progression, which was backed by an anti-Tspan8 blockade of CIC-TEX binding.
CONCLUSIONS: This in depth report on the in vitro and in vivo impact of CIC-TEX on CD44v6kd and Tspan8kd Non-CIC unravels hub CIC-TEX activity, highlighting a prominent contribution of the CIC-markers CD44v6 to signaling cascade activation, transcription, translation and miRNA processing in Non-CIC and of Tspan8 to CIC-TEX targeting. Blocking CIC-TEX binding/uptake and uptake-initiated target cell activation significantly mitigated the deleterious CIC-TEX impact on CD44v6kd and Tspan8kd Non-CIC.

Tirella A, Kloc-Muniak K, Good L, et al.
CD44 targeted delivery of siRNA by using HA-decorated nanotechnologies for KRAS silencing in cancer treatment.
Int J Pharm. 2019; 561:114-123 [PubMed] Related Publications
KRAS is a small GTPase that regulates cell proliferation and survival. In tumors, the KRAS gene is mutated, and leading to unregulated tumor growth. Despite the recognized importance of KRAS in cancer, attempts to develop small molecule inhibitors have proved unsuccessful. An alternative strategy is gene silencing and the use of small nucleic acid sequences (e.g. siRNA, shRNA), has been reported to successfully downregulate KRAS. In this study we developed ternary nanocomplexes to deliver an anti-KRAS siRNA to colorectal cancer cells, exploiting the interaction of hyaluronic acid (HA) with CD44 as a means to achieve selective targeting of CD44-positive cancer cells. Two different polycations, poly(hexamethylene biguanide) and chitosan, were complexed with siRNA and coated with HA. Physico-chemical properties and stability of nanoparticles were characterized, including size, surface charge, and degree of siRNA protection. We demonstrate nanoparticle internalization (flow cytometry), siRNA cytosolic release (confocal microscopy) and KRAS silencing (RT-qPCR) in CD44

Terasaki M, Masaka S, Fukada C, et al.
Salivary Glycine Is a Significant Predictor for the Attenuation of Polyp and Tumor Microenvironment Formation by Fucoxanthin in AOM/DSS Mice.
In Vivo. 2019 Mar-Apr; 33(2):365-374 [PubMed] Free Access to Full Article Related Publications
Background/ Aim: A high polar xanthophyll of Fucoxanthin (Fx) is abundantly contained in edible brown algae, and it has chemopreventive effects in mouse cancer models, however, the underlying mechanisms of these effects are not well understood. Thus, we aimed to investigate the effects of Fx on the tumor microenvironment in cancer model mice.
MATERIALS AND METHODS: We investigated the effect of Fx (30 mg/kg body weight) in a variety of cell types within the tumor microenvironment of α mouse preclinical colorectal cancer model and analyzed the mouse saliva in search of predictors for cancer chemopreventive effects.
RESULTS: Fx administration significantly decreased the number of colorectal polyps and tended to decrease colonic lesions compared to untreated control mice. In addition, Fx administration showed significantly lower numbers of colorectal cancer stem cells-like CD44
CONCLUSION: Our results suggest that salivary glycine may be a predictor representing the chemopreventive effect of Fx in mice.

Akamine T, Tagawa T, Ijichi K, et al.
The Significance of CD44 Variant 9 in Resected Lung Adenocarcinoma: Correlation with Pathological Early-Stage and EGFR Mutation.
Ann Surg Oncol. 2019; 26(5):1544-1551 [PubMed] Related Publications
BACKGROUND: CD44 isoforms serve as a marker for cancer stem cells. CD44 variant 9 (CD44v9) contributes to the defense against reactive oxygen species, resulting in resistance to chemoradiotherapy. However, the significance of CD44v9 in patients with lung adenocarcinoma is unknown.
METHODS: We used immunohistochemical analysis to retrospectively analyze CD44v9 expression in 268 surgically resected lung adenocarcinomas and investigated the association between CD44v9 expression and patients' clinicopathological features.
RESULTS: The expression of CD44v9 in 193 of 268 (72.0%) patients was significantly associated with early-stage cancer, low-grade tumors, absence of vessel and pleural invasion, and a mutated epidermal growth factor receptor (EGFR) gene. Multivariate logistic analysis revealed that CD44v9 expression was significantly associated with early-stage disease [odds ratio (OR) 0.29, 95% confidence interval (CI) 0.14-0.59; p < 0.001] and mutant EGFR (OR 2.53, 95% CI 1.06-6.04; p = 0.036). The percentage of CD44v9-positive tumors was higher in the earlier stages of disease; however, there was no significant difference in the survival of patients in each stage of disease who had positive or negative CD44v9 expression.
CONCLUSION: CD44v9 was highly expressed in EGFR-mutant tumors, particularly in early-stage lung adenocarcinoma, suggesting that CD44v9 expression may play an important role in EGFR-mutant tumors.

Strekalova E, Malin D, Weisenhorn EMM, et al.
S-adenosylmethionine biosynthesis is a targetable metabolic vulnerability of cancer stem cells.
Breast Cancer Res Treat. 2019; 175(1):39-50 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
PURPOSE: Many transformed cells and embryonic stem cells are dependent on the biosynthesis of the universal methyl-donor S-adenosylmethionine (SAM) from methionine by the enzyme MAT2A to maintain their epigenome. We hypothesized that cancer stem cells (CSCs) rely on SAM biosynthesis and that the combination of methionine depletion and MAT2A inhibition would eradicate CSCs.
METHODS: Human triple (ER/PR/HER2)-negative breast carcinoma (TNBC) cell lines were cultured as CSC-enriched mammospheres in control or methionine-free media. MAT2A was inhibited with siRNAs or cycloleucine. The effects of methionine restriction and/or MAT2A inhibition on the formation of mammospheres, the expression of CSC markers (CD44
RESULTS: Methionine restriction inhibited mammosphere formation and reduced the CD44
CONCLUSIONS: Our findings point to SAM biosynthesis as a unique metabolic vulnerability of CSCs that can be targeted by combining methionine depletion with MAT2A inhibition to eradicate drug-resistant CSCs.

Kars MD, Yıldırım G
Determination of the target proteins in chemotherapy resistant breast cancer stem cell-like cells by protein array.
Eur J Pharmacol. 2019; 848:23-29 [PubMed] Related Publications
Breast cancer comes second among the causes of cancer deaths of women. Although new generation hormone therapy is a promising strategy, re-occurrence or emergence of drug resistance limits the success. According to the theory of cancer stem cells (CSCs); CSCs are immortal, tumor inducing and self renewing pluripotent cells and multiply as chemotherapy proceeds, making the chemotherapy inefficient. Emerging scientific reports indicate that the mechanisms of drug resistance are the main features that CSCs gain actually. Due to this fact, cancer stem cell markers should be clarified to target CSCs and this will play important role to reverse drug resistance. In this study, MCF-7/Pac, a cell line resistant to microtubule inhibitor paclitaxel and multiple drugs permanently, was used as a reference cell line for drug resistant mammary cancer. It has some properties that breast cancer stem cells possess so it is considerable to isolate breast cancer stem cell-like cells from MCF-7/Pac population. The chemotherapy resistant breast cancer stem-like (BCSC-like) cells were sorted from MCF-7/Pac population by using markers CD44, CD24 and ALDH. At the next step the proteins that are up-regulated in BCSC-like cells were determined by protein array analysis. Additionally the effect of paclitaxel on BCSC-like cell proliferation was determined. The MCF-7/Pac population contains 12.4% BCSC-like cells. The cells bearing BCSC-like cell phenotype exhibited resistance to paclitaxel. The over-expressed growth factors, MMP proteins, Frizzled proteins and IL-23 were found to be related to the BCSC-like cell proliferation. These results will guide both basic science and medical science.

Jo JH, Park SB, Park S, et al.
Novel Gastric Cancer Stem Cell-Related Marker LINGO2 Is Associated with Cancer Cell Phenotype and Patient Outcome.
Int J Mol Sci. 2019; 20(3) [PubMed] Article available free on PMC after 01/05/2020 Related Publications
The expression of leucine-rich repeat and immunoglobulin-like domain-containing nogo receptor-interacting protein 2 (LINGO2) has been reported in Parkinson's disease; however, its role in other diseases is unknown. Gastric cancer is the second leading cause of cancer death. Cancer stem cells (CSC) are a subpopulation of cancer cells that contribute to the initiation and invasion of cancer. We identified LINGO2 as a CSC-associated protein in gastric cancers both in vitro and in patient-derived tissues. We studied the effect of LINGO2 on cell motility, stemness, tumorigenicity, and angiogenic capacity using cells sorted based on LINGO2 expression and LINGO2-silenced cells. Tissue microarray analysis showed that LINGO2 expression was significantly elevated in advanced gastric cancers. The overall survival of patients expressing high LINGO2 was significantly shorter than that of patients with low LINGO2. Cells expressing high LINGO2 showed elevated cell motility, angiogenic capacity, and tumorigenicity, while LINGO2 silencing reversed these properties. Silencing LINGO2 reduced kinase B (AKT)/extracellular signal-regulated kinase (ERK)/ERK kinase (MEK) phosphorylation and decreased epithelial-mesenchymal transition (EMT)-associated markers-N-Cadherin and Vimentin and stemness-associated markers- POU class 5 homeobox 1 (OCT4) and Indian hedgehog (IHH), and markedly decreased the CD44⁺ population. These indicate the involvement of LINGO2 in gastric cancer initiation and progression by altering cell motility, stemness, and tumorigenicity, suggesting LINGO2 as a putative target for gastric cancer treatment.

Zhang H, Brown RL, Wei Y, et al.
CD44 splice isoform switching determines breast cancer stem cell state.
Genes Dev. 2019; 33(3-4):166-179 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Although changes in alternative splicing have been observed in cancer, their functional contributions still remain largely unclear. Here we report that splice isoforms of the cancer stem cell (CSC) marker CD44 exhibit strikingly opposite functions in breast cancer. Bioinformatic annotation in patient breast cancer in The Cancer Genome Atlas (TCGA) database reveals that the CD44 standard splice isoform (CD44s) positively associates with the CSC gene signatures, whereas the CD44 variant splice isoforms (CD44v) exhibit an inverse association. We show that CD44s is the predominant isoform expressed in breast CSCs. Elimination of the CD44s isoform impairs CSC traits. Conversely, manipulating the splicing regulator ESRP1 to shift alternative splicing from CD44v to CD44s leads to an induction of CSC properties. We further demonstrate that CD44s activates the PDGFRβ/Stat3 cascade to promote CSC traits. These results reveal CD44 isoform specificity in CSC and non-CSC states and suggest that alternative splicing provides functional gene versatility that is essential for distinct cancer cell states and thus cancer phenotypes.

Ou H, Chen Z, Xiang L, et al.
Frizzled 2-induced epithelial-mesenchymal transition correlates with vasculogenic mimicry, stemness, and Hippo signaling in hepatocellular carcinoma.
Cancer Sci. 2019; 110(4):1169-1182 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Prior observation has indicated that Frizzled 2 (FZD2)-induced epithelial-mesenchymal transition (EMT) could be a key step in metastasis and early recurrence of hepatocellular carcinoma (HCC). However, the mechanism underlying tumor development and progression due to aberrant FZD2 expression is poorly defined. Here, we provide evidence that FZD2 is a driver for EMT, cancer stem cell properties, and vasculogenic mimicry (VM) in HCC. We found that FZD2 was highly expressed in two cohorts of Chinese hepatitis B virus-related HCC patients, and that high FZD2 expression was associated with poor prognosis. Concerning the mechanism, gain- and loss-of-function experiments showed the oncogenic action of FZD2 in HCC cell proliferation, apoptosis, migration, and invasion. Further investigations in vitro and in vivo suggested that FZD2 promotes the EMT process, enhances stem-like properties, and confers VM capacity to HCC cells. Notably, integrative RNA sequencing analysis of FZD2-knockdown cells indicated the enrichment of Hippo signaling pathway. Taken together, our data suggest for the first time that FZD2 could promote clinically relevant EMT, CD44

Wu CH, Chuang HY, Wang CL, et al.
Estradiol induces cell proliferation in MCF‑7 mammospheres through HER2/COX‑2.
Mol Med Rep. 2019; 19(3):2341-2349 [PubMed] Related Publications
Cluster of differentiation (CD)44+/CD24- breast cancer cells have stem cell‑like characteristics and are potent initiators of tumorigenesis. Mammosphere cells can partially initiate breast tumorigenesis by inducing estradiol (E2)‑dependent breast cancer cells. However, the mechanisms by which E2 mediates cancer formation in MCF‑7 mammosphere (MS) cells have remained elusive. In the present study, MS cells were isolated by sphere culture. It was possible to maintain these MS cells in culture for long periods of time, while retaining the CD44+/CD24- stem cell marker status. The CD44+/CD24- status was confirmed by flow cytometry. Furthermore, the stem‑cell markers Musashi‑1, cytokeratin (CK)7 and CK19 were identified by immunofluorescence microscopy. It was revealed that treatment of MS cells with E2 increased the expression of CD44, whereas decreased the expression of CD24 on MS cells. In addition, treatment with E2 increased colony formation by MS cells. E2 also induced cyclooxygenase‑2 (COX‑2) expression in MS cells, which promoted their proliferation through the estrogen receptor/human epidermal growth factor receptor 2 (HER2)/mitogen‑activated protein kinase/phosphoinositide‑3 kinase signaling pathway. The results suggested a tumorigenic mechanism by which E2 promotes tumor cell proliferation via HER2/COX‑2 signaling. The present study provided evidence for the molecular impact of E2 on breast tumorigenesis, and suggested possible strategies for preventing and treating human breast cancer.

Rahman MR, Islam T, Gov E, et al.
Identification of Prognostic Biomarker Signatures and Candidate Drugs in Colorectal Cancer: Insights from Systems Biology Analysis.
Medicina (Kaunas). 2019; 55(1) [PubMed] Article available free on PMC after 01/05/2020 Related Publications
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.

Ning Y, Feng W, Cao X, et al.
Genistein inhibits stemness of SKOV3 cells induced by macrophages co-cultured with ovarian cancer stem-like cells through IL-8/STAT3 axis.
J Exp Clin Cancer Res. 2019; 38(1):19 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
BACKGROUND: Recent studies showed that macrophages co-cultured with ovarian cancer stem-like cells (OCSLCs) induced SKOV3 cell stemness via IL-8/STAT3 signaling. Genistein (GEN) demonstrates chemopreventive activity in inflammation-associated cancers. The present study aimed to examine whether and if GEN inhibits the stemness of SKOV3 and OVCA-3R cells induced by co-culture of THP-1 macrophages and SKOV3-derived OCSLCs.
METHODS: The co-culture was treated with or without different concentrations (10, 20, and 40 μmol/L) of GEN for 24 h. Depletion or addition of IL-8 in Co-CM and knockdown or overexpression of STAT3 in THP-1 macrophages was performed to demonstrate the possible associated mechanisms. The combined effects of GEN and STAT3 knockdown were examined with the nude mouse modle by co-injection of SKOV3-derived OCSLCs with THP-1 macrophages.
RESULTS: Our results showed that GEN down-regulated CD163 and p-STAT3 expression of THP-1 macrophage, decreased the levels of IL-10, increased the levels of IL-12 and nitric oxide (NO) in the conditioned medium, and reduced the clonogenic and sphere-forming capacities and the expression of CD133 and CD44 in SKOV3 cells induced by co-culture of THP-1 macrophages and OCSLCs in a dose-dependent manner. Moreover, depletion or addition of IL-8 enhanced or attenuated the effect of GEN. Additionally, knockdown or overepression of STAT3 in THP-1 macrophages potentiated or attenuated the inhibitory effects of GEN. Importantly, STAT3 overexpression retrieved the effects of IL-8 combined with GEN depletion on M2 polarization of THP-1 macrophages and stemness of SKOV3 cells induced by co-culture. The combination of GEN and STAT3 knockdown cooperatively inhibited the growth of tumors co-inoculated with OCSLCs/THP-1 macrophages in nude mice in vivo through blocking IL-8/STAT3 signaling.
CONCLUSIONS: In summary, our findings suggested that GEN can inhibit the increased M2 polarization of macrophages and stemness of ovarian cancer cells by co-culture of macrophages with OCSLCs through disrupting IL-8/STAT3 signaling axis. This assisted GEN to be as a potential chemotherapeutic agent in human ovarian cancer.

Zhu J, Huang G, Hua X, et al.
CD44s is a crucial ATG7 downstream regulator for stem-like property, invasion, and lung metastasis of human bladder cancer (BC) cells.
Oncogene. 2019; 38(17):3301-3315 [PubMed] Related Publications
Over half a million US residents are suffering with bladder cancer (BC), which costs a total $4 billion in treatment annually. Although recent studies report that autophagy-related gene 7 (ATG7) is overexpressed in BCs, the regulatory effects of ATG7 on cancer stem-like phenotypes and invasion have not been explored yet. Current studies demonstrated that the deficiency of ATG7 by its shRNA dramatically reduced sphere formation and invasion in vitro, as well as lung metastasis in vivo in human invasive BC cells. Further studies indicated that the knockdown of ATG7 attenuated the expression of CD44 standard (CD44s), while ectopic introduction of CD44s, was capable of completely restoring sphere formation, invasion, and lung metastasis in T24T(shATG7) cells. Mechanistic studies revealed that ATG7 overexpression stabilized CD44s proteins accompanied with upregulating USP28 proteins. Upregulated USP28 was able to bind to CD44s and remove the ubiquitin group from CD44s' protein, resulting in the stabilization of CD44s protein. Moreover, ATG7 inhibition stabilized AUF1 protein and thereby reduced tet1 mRNA stability and expression, which was able to demethylate usp28 promoter, reduced USP28 expression, finally promoting CD44s degradation. In addition, CD44s was defined to inhibit degradation of RhoGDIβ, which in turn promotes BC invasion. Our results demonstrate that CD44s is a key ATG7 downstream regulator of the sphere formation, invasion, and lung metastasis of BCs, providing significant insight into understanding the BC invasions, metastasis, and stem-like properties.

Li Y, Zhang T, Qin S, et al.
Effects of UPF1 expression on EMT process by targeting E‑cadherin, N‑cadherin, Vimentin and Twist in a hepatocellular carcinoma cell line.
Mol Med Rep. 2019; 19(3):2137-2143 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. It has been reported that HCC has a poor prognosis. In the majority of cases, once metastatic, HCC is incurable. To identify an effective treatment for HCC, it is important to understand the underlying molecular mechanisms of HCC‑associated occurrence, proliferation, metastasis and carcinogenesis. In the present study, the role of Up‑frameshift 1 (UPF1), a potential tumor suppressor, was investigated in the HCC cell lines. The expression levels of UPF1 in an HCC cell line were examined by reverse transcription‑quantitative polymerase chain reaction. The expression levels of 19 key proteins in numerous signaling pathways were detected via protein array analysis in the presence of UPF1 overexpression. The present study further investigated the effects of UPF1 expression levels on the epithelial‑mesenchymal transition (EMT) process by targeting E‑cadherin, N‑cadherin, Vimentin and Twist‑related protein 1 (Twist). The results of the present study revealed that UPF1 was significantly downregulated in an HCC cell line. The majority of the proteins exhibited upregulated expression levels in the presence of UPF1 overexpression in the HCC cell line, Huh‑7. Key proteins, including cluster of differentiation (CD)31 (platelet endothelial cell adhesion molecule‑1), Vimentin, CD44, PCNA, Ki‑67, N‑Cadherin, Survivin, P53, Met and retinoblastoma exhibited a significant association with UPF1. Furthermore, western blotting indicated that the expression levels of N‑cadherin, Vimentin and Twist were notably upregulated while UPF1 was overexpressed; however, E‑cadherin was downregulated and opposing observations were reported with protein array analysis. In summary, E‑cadherin expression levels were regulated by the manifold, and UPF1, a potential tumor suppressor, may promote the EMT process in Huh‑7 HCC cells. The findings of the present study suggested that UPF1 expression levels affected the EMT process by targeting E‑cadherin, N‑cadherin, Vimentin and Twist.

Handa T, Katayama A, Yokobori T, et al.
Carboxypeptidase A4 accumulation is associated with an aggressive phenotype and poor prognosis in triple-negative breast cancer.
Int J Oncol. 2019; 54(3):833-844 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Using whole transcriptome analysis and a lentiviral short hairpin RNA screening library, carboxypeptidase A4 (CPA4) was identified as a novel marker in breast cancer and a therapeutic target in triple‑negative breast cancer (TNBC) in the present study. Immunohistochemistry was used to evaluate the presence of CPA4, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, Ki67, epidermal growth factor receptor, cytokeratin 5/6, aldehyde dehydrogenase 1, cluster of differentiation (CD)44, CD24, claudins, E‑cadherin, vimentin and androgen receptor in 221 cases of breast cancer, including 68 TNBC cases. The effects of CPA4 on the viability and migration ability of TNBC cells were analyzed using RNA interference methods. Increased CPA4 expression, specifically in the cytoplasm of cancer tissue cells, was detected. Furthermore, high CPA4 expression in TNBC cases was associated with low expression of E‑cadherin and with the expression of cancer stem cell markers (high CD44/low CD24). Patients with TNBC and high levels of CPA4 expression had a significantly poorer prognosis compared with those with low CPA4 expression. Notably, viability and migration were reduced, but E‑cadherin expression was upregulated in CPA4‑suppressed TNBC cells. The present data suggested that CPA4 may be a novel inducer for epithelial‑mesenchymal transition, which is characterized by the downregulation of E‑cadherin and mesenchymal phenotypes. To conclude, CPA4 may be a marker for poor prognosis and a promising therapeutic target in TNBC with aggressive phenotypes.

Jiang M, Qiu N, Xia H, et al.
Long non‑coding RNA FOXD2‑AS1/miR‑150‑5p/PFN2 axis regulates breast cancer malignancy and tumorigenesis.
Int J Oncol. 2019; 54(3):1043-1052 [PubMed] Related Publications
Breast cancer (BC) is a common cancer and leading cause of cancer‑associated mortality in women. Abnormal expression of long non‑coding RNA FOXD2 adjacent opposite strand RNA 1 (FOXD2‑AS1) was associated with the development of a number of tumors. However, whether FOXD2‑AS1 is dysregulated in BC and its underlying mechanisms remain unclear. In the present study, it was identified that FOXD2‑AS1 expression was upregulated in BC tissue, cell lines and sphere subpopulation. Additionally, the abnormal upregulation of FOXD2‑AS1 predicted poor prognosis in patients with BC. Furthermore, downregulation of FOXD2‑AS1 decreased cell proliferation, and migratory and invasive abilities in BC cells, and decreased the growth of transplanted tumors in vivo. Downregulation of FOXD2‑AS1 decreased the percentage of CD44 antigen+/signal transducer CD24- in breast cancer stem cell (BCSC) cells, and decreased the expression of numerous stem factors, including Nanog, octamer‑binding transcription factor 4 (Oct4), and sex determining region Y‑box 2 (SOX2), and inhibited the epithelial‑mesenchymal transition process. FOXD2‑AS1 was identified to be primarily located in the cytoplasm. Using bioinformatics analysis, a reporter gene assay and reverse transcription‑polymerase chain reaction assays, it was demonstrated that microRNA (miR)‑150‑5p was able to bind directly with the 3'‑untranslated region of FOXD2‑AS1 and PFN2 mRNA. miR‑150‑5p mimics decreased the cell proliferation, migration and invasion of BC cells. FOXD2‑AS1 knockdown significantly inhibited the miR‑150‑5p inhibitor‑induced increase in Nanog, Oct4 and SOX2 expression. The miR‑150‑5p inhibitor‑induced increase in N‑cadherin, and decrease in E‑cadherin and vimentin was inhibited by FOXD2‑AS1 knockdown. Profilin 2 (PFN2) expression was significantly upregulated in BC tissues. Additionally, the abnormal upregulation of PFN2 was associated with poor prognosis in patients with BC. FOXD2‑AS1 and PFN2 expression was positively correlated. Collectively, the present results demonstrated the role of the FOXD2‑AS1/miR‑150‑5p/PFN2 axis in the development of BC, and provides novel targets for the treatment of BC, and potential biomarkers for diagnosis and prognosis of BC.

Qiu X, Wang W, Li B, et al.
Targeting Ezh2 could overcome docetaxel resistance in prostate cancer cells.
BMC Cancer. 2019; 19(1):27 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
BACKGROUND: Docetaxel was used to treat metastatic CRPC patients. However, Doc resistance in prostate cancer (PCa) hinders its clinical application.
OBJECTIVE: To understand the underlying mechanisms by which Doc resistance is developed and to find novel therapeutic target to cure Doc resistant PCa has clinical importance.
METHODS: We established Doc resistant cell lines and explored the role of Ezh2 in the development of Doc resistance by overexpressing its cDNA or using its inhibitor.
RESULTS: We found that Ezh2 was induced in our established Doc resistant (DocR) cells, which was attributable to the silenced expression of miR-101-3p and miR-138-5p. Blockage of Ezh2 activity by either inhibitor or miRNA mimics could overcome Doc resistance by suppressing Doc-induced cancer stem cells populations. Mechanistically, Ezh2 activity was required for the induced expression of Nanog, Sox2 and CD44 upon Doc treatment.
CONCLUSIONS: Targeting Ezh2 could overcome Doc resistance.

Kuo SZ, Honda CO, Li WT, et al.
Metformin Results in Diametrically Opposed Effects by Targeting Non-Stem Cancer Cells but Protecting Cancer Stem Cells in Head and Neck Squamous Cell Carcinoma.
Int J Mol Sci. 2019; 20(1) [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Cancer stem cells (CSCs) have been shown as a distinct population of cancer cells strongly implicated with resistance to conventional chemotherapy. Metformin, the most widely prescribed drug for diabetes, was reported to target cancer stem cells in various cancers. In this study, we sought to determine the effects of metformin on head and neck squamous cell carcinoma (HNSCC). CSCs and non-stem HNSCC cells were treated with metformin and cisplatin alone, and in combination, and cell proliferation levels were measured through MTS assays. Next, potential targets of metformin were explored through computational small molecule binding analysis. In contrast to the reported effects of metformin on CSCs in other cancers, our data suggests that metformin protects HNSCC CSCs against cisplatin in vitro. Treatment with metformin resulted in a dose-dependent induction of the stem cell genes CD44, BMI-1, OCT-4, and NANOG. On the other hand, we observed that metformin successfully decreased the proliferation of non-stem HNSCC cells. Computational drug⁻protein interaction analysis revealed mitochondrial complex III to be a likely target of metformin. Based on our results, we present the novel hypothesis that metformin targets complex III to reduce reactive oxygen species (ROS) levels, leading to the differential effects observed on non-stem cancer cells and CSCs.

Disclaimer: This site is for educational purposes only; it can not be used in diagnosis or treatment.

Cite this page: Cotterill SJ. CD44, Cancer Genetics Web: Accessed:

Creative Commons License
This page in Cancer Genetics Web by Simon Cotterill is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Note: content of abstracts copyright of respective publishers - seek permission where appropriate.

 [Home]    Page last revised: 31 August, 2019     Cancer Genetics Web, Established 1999