Research IndicatorsGraph generated 14 March 2017 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 14 March, 2017 using data from PubMed, MeSH and CancerIndex
Specific Cancers (15)
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).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
COSMIC, Sanger Institute
Somatic mutation information and related details
GEO Profiles, NCBI
Search the gene expression profiles from curated DataSets in the Gene Expression Omnibus (GEO) repository.
Latest Publications: FAS (cancer-related)
Zhang H, Wang F, Hu YSTARD13 promotes hepatocellular carcinoma apoptosis by acting as a ceRNA for Fas.
Biotechnol Lett. 2017; 39(2):207-217 [PubMed
] Related Publications
OBJECTIVES: To study the roles of STARD13 in cellular apoptosis of hepatocellular carcinoma (HCC).
RESULTS: Quantitative real-time PCR and immunohistochemistry analyses showed that the expression levels of STARD13 and Fas were lower in clinical HCC tissues than in normal tissues and were positively correlated, which is consistent with the results analyzed by The Cancer Genome Atlas (TCGA) data. Patients with higher STARD13 or Fas expression levels had longer overall survival. Additionally, STARD13 3'-UTR enhanced cellular apoptosis and the 3'-UTRs of STARD13 and Fas were predicted to harbor nine similar miRNA binding sites. And STARD13 3'-UTR promoted Fas expression in a 3'-UTR- and miRNA-dependent way and increased the sensitivity of HCC cells to chemotherapy. Importantly, the coding sequence of STARD13 did not increase Fas expression.
CONCLUSIONS: STARD13 3'-UTR promotes HCC apoptosis through acting as a ceRNA for Fas.
Cacan EHistone Deacetylase-1-mediated Suppression of FAS in Chemoresistant Ovarian Cancer Cells.
Anticancer Res. 2016; 36(6):2819-26 [PubMed
] Related Publications
BACKGROUND: Loss of FAS expression in ovarian cancer cells has recently been associated with resistance to chemotherapeutic drugs. However, the mechanism for suppression of FAS expression is unknown.
MATERIALS AND METHODS: The cell surface and transcript expressions of death receptors in parental chemosensitive (A2780) and their derivative chemoresistant (A2780-AD) ovarian cancer cells were determined by flow cytometry and quantitative real-time polymerase chain reaction, respectively. The epigenetic regulation of FAS promoters in both A2780 and A2780-AD ovarian epithelial cells were determined by chromatin immunoprecipitation assays.
CONCLUSION: This study demonstrated that expression of FAS is suppressed in A2780-AD cells compared to parental A2780 ovarian cells. No difference in DNA methylation was observed at FAS promoters between A2780-AD cells compared to parental cells. However, the level of acetylated histone H3 associated with FAS promoter in A2780-AD cells was significantly lower compared to parental cells, and there was a corresponding increase in histone deacetylase 1 (HDAC1) enzyme associated with the FAS promoter in resistant cells. Knockdown of HDAC1 expression, and pharmacological inhibition of HDAC enzymatic activity significantly increased FAS expression in resistant A2780-AD cells. These results suggest that epigenetic changes in histone modifications may contribute to the loss of FAS expression in chemoresistant ovarian cancer cells and that enhancement of FAS expression could increase tumor cell sensitivity to immune cells.
Yang X, Tietje AH, Yu X, Wei YMouse interleukin-12/FasTI: A novel bi-functional fusion protein for cancer immuno/gene therapy.
Int J Oncol. 2016; 48(6):2381-6 [PubMed
] Related Publications
Whereas cancer immunotherapy with cytokines in recent research was demonstrated effective in activating immune response against tumor cells, one major obstacle with the use of these cytokines is their severe side effects when delivered systemically at high doses. Another challenge is that advanced tumor cells often evade immunosurveillance of the immune system as well as of the Fas-mediated apoptosis by various mechanisms. We report the design and preliminary evaluation of the antitumor activity of a novel fusion protein-mIL-12/FasTI, consisting of mouse interleukin-12 and the transmembrane and intracellular domains of mouse Fas. The fusion construct (pmIL-12/FasTI) was transfected into mouse lung carcinoma cell line TC-1. Stable cell clones expressing the fusion protein were established as assayed by RT-PCR and immunohistochemistry. ELISA and cell proliferation analyses demonstrated that NK cells were effectively activated by the fusion protein with increased IFN-γ production and cytotoxicity. Enhanced caspase-3 activity of the clones when co-cultured with NK cells indicated that apoptosis was induced through Fas/FasL signaling pathway. The preliminary results suggest a synergized anticancer activity of the fusion protein. It may represent a promising therapeutic agent for cancer treatment.
Sun Y, Yu W, Sturgis EM, et al.Site disparities in apoptotic variants as predictors of risk for second primary malignancy in patients with squamous cell carcinoma of the head and neck.
BMC Cancer. 2016; 16:70 [PubMed
] Free Access to Full Article Related Publications
BACKGROUND: FAS/FASL promoter variants are considered in altering transcriptional activity of those genes and consequently alter regulation of cell death. However, no studies have investigated whether tumor sites contribute to the association between FAS/FASL polymorphisms and risk for second primary malignancy (SPM).
METHOD: In this study, FAS670 A > G, FAS1377 G > A, FASL124 A > G, and FASL844C > T polymorphisms were genotyped in 752 OPC and 777 non-OPC patients. Both univariate and multivariable cox proportional hazard models were used to assess the associations.
RESULTS: The univariate and multivariable analyses showed that patients with index OPC and FASL844 CT/TT genotype had significantly increased risk of SPM (cHR, 2.5; 95% CI, 1.1-5.8, P = 0.043 and aHR, 2.7; 95% CI, 1.2-6.0, P = 0.032) compared with those with FASL844 CC genotype as the reference group, while index non-OPC patients with FAS670 AG/GG and FasL844 CT/TT genotypes had significantly increased risk of SPM (cHR, 2.2 and 1.8; 95% CI, 1.2-5.7 and 1.1-3.2; and P = 0.04 and 0.041, respectively and aHR, 2.4 and 1.7; 95% CI, 1.1-5.1 and 1.0-3.0; and P = 0.043 and 0.049, respectively) compared with their corresponding AA and CC genotypes . Moreover, patients carrying more FAS/FASL variants significantly increased risk of SPM among index non-OPC patients. The stratified analysis showed that smoking status differently modified the associations between FAS/FASL polymorphisms and risk of SPM among index non-OPC from OPC patients.
CONCLUSION: These results suggested that FAS/FASL polymorphisms might significantly modify SPM risk among patients with SCCHN in a tumor site-specific manner.
The case-control study aims to investigate the association of Fas and FasL genetic polymorphisms (Fas-670A/G (rs1800682), Fas-1377G/A (rs2234767) and FasL-844T/C (rs763110)) with esophageal carcinoma susceptibility in a north Chinese population. A total of 204 patients with esophageal carcinoma and 248 healthy controls were enrolled from Henan, China and genotyped by the polymerase chain reaction and restriction fragment length polymorphism method. There were no significant differences in distributions of their genotypes frequencies between patients and controls in Fas-670A/G, Fas-1377G/A and FasL-844T/C polymorphisms (P > 0.05). Stratified analysis showed that no significant association was found between esophageal carcinoma and gene polymorphisms of Fas-670 A/G, Fas-1377G/A, and FasL-844T/C (P > 0.05). Genetic polymorphisms in the death pathway genes Fas and FasL were not associated with risk of developing esophageal carcinoma in a north Chinese population.
FAS rs2234767 (-1377 G>A), rs1800682 (-670 A>G) and FASLG rs763110 (-844 C>T) promoter polymorphisms can influence transcriptional activities of the genes and thus multiple tumors susceptibility. To investigate their association with risk of colorectal cancer (CRC), the three SNPs were genotyped in 878 cases and 884 controls and the results showed that the FAS rs2234767 and rs1800682 were in a high linkage disequilibrium (LD) with each other (D' = 0.994) and jointly contributed to an increased risk of CRC (without vs. with rs2234767 GG/rs1800682 AA genotypes, adjusted OR = 1.30, 95% CI = 1.05 - 1.61). In vivo ChIP assays evaluated the effect of rs2234767 and rs1800682 on recruitment of SP1 and STAT1, respectively, to chromatin. The results showed SP1 interacting specifically with STAT1 recruited to their respective motifs for transcriptional activation. The mutant alleles rs2234767 A and rs1800682 G jointly affected coupled SP1 and STAT1 recruitment to chromatin. The interplay between SP1 and STAT1 was critical for the functional outcome of rs2234767 and rs1800682 in view of their high LD. In conclusion, the FAS rs2234767 and rs1800682 polymorphisms were in high LD with each other, and they jointly contributed to an increased risk of CRC by altering recruitment of SP1/STAT1 complex to the FAS promoter for transcriptional activation.
Edathara PM, Gorre M, Kagita S, et al.Association of promoter polymorphisms of Fas -FasL genes with development of Chronic Myeloid Leukemia.
Tumour Biol. 2016; 37(4):5475-84 [PubMed
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Chronic myeloid leukemia (CML) is a monoclonal myeloproliferative disorder of hematopoietic stem cells (HSCs), characterized by reciprocal translocation, leading to the formation of BCR-ABL oncogene with constitutive tyrosine kinase (TK) activity. This oncogene is known to deregulate different downstream pathways which ultimately lead to cell proliferation, defective DNA repair, and inhibition of apoptosis. Fas (Fas cell surface death receptor) is a member of tumor necrosis factor (TNF) superfamily which interacts with its ligand, FasL, to initiate apoptosis. Promoter polymorphisms in Fas-FasL genes are known to influence the apoptotic signaling. Hence, the present study has been aimed to find out the association of the promoter polymorphisms in Fas and FasL genes with the development and progression of CML. Blood samples from 772 subjects (386 controls and 386 cases) were collected and genotyped for Fas-FasL gene polymorphisms through PCR-RFLP method. The association between SNPs and clinical outcome was analyzed using statistical softwares like SPSS version 20, SNPSTATs, and Haploview 2.1. The study revealed a significant association of Fas -670 G>A and FasL -844 T>C polymorphisms with the development of CML while Fas -670 AG was associated with accelerated phase. Combined risk analysis by taking the risk genotypes in cases and controls revealed a significant increase in CML risk with increase in number of risk genotypes (one risk genotype-OR 1.99 (1.44-2.76), p < 0.0001; two risk genotypes-OR 3.33 (1.91-5.81), p < 0.0001). Kaplan-Meier survival analysis of Fas -670 A>G and FasL -844 T>C showed reduced event-free survival in patients carrying the variant genotypes, Fas -670 GG, 32.363 ± 6.33, and FasL -844 CC, 33.489 ± 5.83, respectively. Our findings revealed a significant association of Fas -670 GG, FasL -844 TC, and CC genotypes with increased risk of CML.
Ras is aberrantly activated in many cancers and active DNA demethylation plays a fundamental role to establish DNA methylation pattern which is of importance to cancer development. However, it was unknown whether and how Ras regulate DNA demethylation during carcinogenesis. Here we found that Ras downregulated thymine-DNA glycosylase (TDG), a DNA demethylation enzyme, by inhibiting the interaction of transcription activator ING4 with TDG promoter. TDG recruited histone lysine demethylase JMJD3 to the Fas promoter and activated its expression, thus restoring sensitivity to apoptosis. TDG suppressed in vivo tumorigenicity of xenograft pancreatic cancer. Thus, we speculate that reversing Ras-mediated ING4 inhibition to activate Fas expression is a potential therapeutic approach for Ras-driven cancers.
Tan SCLetter regarding "CD95 rs1800682 polymorphism and cervical cancer risk: evidence from a meta-analysis" by Zhang et al.
Tumour Biol. 2015; 36(11):8275-6 [PubMed
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Although a standardized approach to radiotherapy has been used to treat breast cancer, regardless of subtype (e.g., luminal, basal), recent clinical data suggest that radiation response may vary significantly among subtypes. We hypothesized that this clinical variability may be due, in part, to differences in cellular radiation response. In this study, we utilized RNA samples for microarray analysis from two sources: 1. Paired pre- and postirradiation breast tumor tissue from 32 early-stage breast cancer patients treated in our unique preoperative radiation Phase I trial; and 2. Sixteen biologically diverse breast tumor cell lines exposed to 0 and 5 Gy irradiation. The transcriptome response to radiation exposure was derived by comparing gene expression in samples before and after irradiation. Genes with the highest coefficient of variation were selected for further evaluation and validated at the RNA and protein level. Gene editing and agonistic antibody treatment were performed to assess the impact of gene modulation on radiation response. Gene expression in our cohort of luminal breast cancer patients was distinctly different before and after irradiation. Further, two distinct patterns of gene expression were observed in our biologically diverse group of breast cancer cell lines pre- versus postirradiation. Cell lines that showed significant change after irradiation were largely luminal subtype, while gene expression in the basal and HER2+ cell lines was minimally impacted. The 100 genes with the most significant response to radiation in patients were identified and analyzed for differential patterns of expression in the radiation-responsive versus nonresponsive cell lines. Fourteen genes were identified as significant, including FAS, a member of the tumor necrosis factor receptor family known to play a critical role in programed cell death. Modulation of FAS in breast cancer cell lines altered radiation response phenotype and enhanced radiation sensitivity in radioresistant basal cell lines. Our findings suggest that cell-type-specific, radiation-induced FAS contributes to subtype-specific breast cancer radiation response and that activation of FAS pathways may be exploited for biologically tailored radiotherapy.
Crozier M, Porter LAPaclitaxel-induced transcriptional regulation of Fas signaling pathway is antagonized by dexamethasone.
Breast Cancer Res Treat. 2015; 154(1):33-44 [PubMed
] Related Publications
Chemotherapy agents like paclitaxel are often a first line of therapy for triple-negative breast cancer patients and a last line of therapy for other aggressive breast cancers. While such agents are effective pro-apoptotic treatments for breast cancer cells, they produce many unwanted side effects. Synthetic glucocorticoids like dexamethasone are commonly prescribed during chemotherapy treatment of breast cancer patients for anti-emetic and anti-hypersensitivity purposes. Dexamethasone, however, is known to enhance cell survival in solid tumors. The prevalent use of dexamethasone in conjunction with paclitaxel in the treatment of breast cancer patients merits concern. Previous studies demonstrate dexamethasone-mediated survival in a subset of breast cancer cells in the presence of paclitaxel. This work expanded the types of cell lines studied and explored the molecular mechanism driving this phenotype. Human breast cancer cell lines representative of several subtypes of breast cancer including triple-negative breast cancer, luminal, and HER2 were treated in the presence and absence of paclitaxel, dexamethasone, and under co-treatment conditions. Cell survival was monitored under differing conditions. We then manipulated aspects of the nuclear factor kappa B (NFkappaB) signaling pathway to elucidate the importance of this pathway in overcoming chemotherapy treatment. All cell lines tested were sensitive to paclitaxel and showed dexamethasone-mediated rescue from paclitaxel-induced apoptosis, but the rescue of overall cell numbers was most pronounced in triple-negative breast cancer cell lines. Dexamethasone and paclitaxel inversely regulated the activity of NFkappaB, which is essential to both paclitaxel-mediated apoptosis and dexamethasone-mediated rescue. The transcriptional target of NFkappaB, Fas receptor, is inversely regulated by paclitaxel and dexamethasone and is a downstream target of paclitaxel-activated NFkappaB. Dexamethasone antagonizes paclitaxel-mediated apoptosis through inhibition of NFkappaB transcription of Fas receptor. Pre-treatment of breast cancer patients with dexamethasone may greatly reduce patient response to paclitaxel. Our study elucidates a novel mechanism of paclitaxel-induced apoptosis in breast cancer cell lines and explicates dexamethasone’s antagonism of paclitaxel.
Bose RN, Moghaddas S, Belkacemi L, et al.Absence of Activation of DNA Repair Genes and Excellent Efficacy of Phosphaplatins against Human Ovarian Cancers: Implications To Treat Resistant Cancers.
J Med Chem. 2015; 58(21):8387-401 [PubMed
] Related Publications
Phosphaplatins, platinum(II) and platinum(IV) complexes coordinated to a pyrophosphate moiety, exhibit excellent antitumor activities against a variety of cancers. To determine whether phosphaplatins trigger resistance to treatment by engaging DNA damage repair genes, a yeast genome-wide fitness assay was used. Treatment of yeast cells with pyrodach-2 (D2) or pyrodach-4 (D4) revealed no particular sensitivity to nucleotide excision repair, homologous recombination repair, or postreplication repair when compared with platin control compounds. Also, TNF receptor superfamily member 6 (FAS) protein was overexpressed in phosphaplatin-treated ovarian tumor cells, and platinum colocalized with FAS protein in lipid rafts. An overactivation of sphingomyelinase (ASMase) was noted in the treated cells, indicating participation of an extrinsic apoptotic mechanism due to increased ceramide release. Our results indicate that DNA is not the target of phosphaplatins and accordingly, that phosphaplatins might not cause resistance to treatment. Activation of ASMase and FAS along with the colocalization of platinum with FAS in lipid rafts support an extrinsic apoptotic signaling mechanism that is mediated by phosphaplatins.
Lifeguard (LFG) is a transmembrane protein which is highly expressed in tissues of the hippocampus and the cerebellum, especially during postnatal development. This protein is responsible for the protection of neurons against Fas-induced apoptosis, and the same effect can be seen in tumor cells derived from mastocarcinoma. However, the molecular function of LFG and its regulation in the carcinogenesis of human breast cells remains to be elucidated. In the present study, we investigated the connection of the interaction of LFG within an array analysis of over 9,000 different proteins. Results showed an interaction between the proteins tripartite motif-containing 21 (TRIM21) and LFG and a negative regulatory effect of TRIM21 towards LFG on the protein level. Furthermore, Fas-induced apoptosis decreased upon the addition of TRIM21 to the cultured cells. These results revealed TRIM21 to be a negative modulator of LFG in cells of mastocarcinoma in vitro. For all analyses, MDA-MB-231 cells were used. The interaction of TRIM21 and LFG was analyzed by co-immunoprecipitation. To examine changes in regulatory processes, western blot analyses, real-time PCR, activity of apoptotic process and flow cytometric analyses were carried out.
Tumor cells generate extracellular superoxide anions and are protected against intercellular apoptosis-inducing HOCl- and NO/peroxynitrite signaling through the expression of membrane-associated catalase. This enzyme decomposes H2O2 and thus prevents HOCl synthesis. It efficiently interferes with NO/peroxynitrite signaling through oxidation of NO and decomposition of peroxynitrite. The regulatory potential of catalase at the crosspoint of ROS and RNS chemical biology, as well as its high local concentration on the outside of the cell membrane of tumor cells, establish tight control of intercellular signaling and thus prevent tumor cell apoptosis. Therefore, inhibition of catalase or its inactivation by singlet oxygen reactivate intercellular apoptosis-inducing signaling. Nitric oxide and peroxynitrite are connected with catalase in multiple and meaningful ways, as (i) NO can be oxidated by compound I of catalase, (ii) NO can reversibly inhibit catalase, (iii) peroxynitrite can be decomposed by catalase and (iv) the interaction between peroxynitrite and H2O2 leads to the generation of singlet oxygen that inactivates catalase. Therefore, modulation of the concentration of free NO through addition of arginine, inhibition of arginase, induction of NOS expression or inhibition of NO dioxygenase triggers an autoamplificatory biochemical cascade that is based on initial formation of singlet oxygen, amplification of superoxide anion/H2O2 and NO generation through singlet oxygen dependent stimulation of the FAS receptor and caspase-8. Finally, singlet oxygen is generated at sufficiently high concentration to inactivate protective catalase and to reactivate intercellular apoptosis-inducing ROS signaling. This regulatory network allows to establish several pathways for synergistic interactions, like the combination of modulators of NO metabolism with enhancers of superoxide anion generation, modulators of NO metabolism that act at different targets and between modulators of NO metabolism and direct catalase inhibitors. The latter aspect is explicitely studied for the interaction between catalase inhibiting acetylsalicylic acid and an NO donor. It is also shown that hybrid molecules like NO-aspirin utilize this synergistic potential. Our data open novel approaches for rational tumor therapy based on specific ROS signaling and its control in tumor cells.
Yee SB, Choi HJ, Chung SW, et al.Growth inhibition of luteolin on HepG2 cells is induced via p53 and Fas/Fas-ligand besides the TGF-β pathway.
Int J Oncol. 2015; 47(2):747-54 [PubMed
] Related Publications
Flavonoids, a class of natural polyphenolic compounds, inhibit cell cycle progression and induce apoptosis. This study was performed to investigate the antiproliferative effect of luteolin, the flavonoid isolated from Ixeris sonchifolia Hance, and to elucidate the detailed apoptotic mechanism in HCC cells. According to the result of MTT assay luteolin possessed antiproliferative effect, and HepG2 cells were the most sensitive to luteolin. Propidium iodide staining, fluorescence activated cell sorting analysis, western blot analysis and RT-PCR were applied to compare the difference of apoptotic event between the two HCC cell lines, with wild-type p53 (HepG2) or not (Hep3B) based on time and concentration. The treatment of luteolin upregulated the expression levels of transforming growth factor β1 (TGF‑β1), p21WAF1/CIP1, p27KIP1, Smad4, and Fas in HCC cells. Thus, the expression of p21WAF1/CIP1 was controlled by another factor, such as TGF‑β1 in addition to p53, and notably the key factor might be p21WAF1/CIP1 in the remarkable switch to G1 cell cycle arrest in HepG2 cells rather than p27KIP1. Luteolin induced apoptotic cell death in Hep3B cells while caused G1 arrest in HepG2 cells. Taken together, we conclude that luteolin induces apoptosis from G1 arrest via three signaling pathways of TGF‑β1, p53, and Fas/Fas-ligand in HCC cells.
BACKGROUND: Fas signaling-activated signal transducers and activators of transcription 3 (STAT3) is required for Fascin upregulation. As an actin-bundling protein, Fascin can mediate gastric cancer (GC) cell migration.
METHODS: Gastric cancer AGS cells were treated with anti-Fas (5 μg/ml) for 2 h, in order to stimulate the activation of the Fas signaling. The in vitro migration of Fas signaling-activated AGS cells was assessed using Transwell chambers. The levels of Fascin and phosphorylated STAT3 were detected by Western blotting analyses. Nude mice were injected intravenously with AGS cells treated with anti-Fas or treated with STAT3 inhibitor without anti-Fas; tumor pulmonary metastases were measured. Fascin protein expression in tumor tissues was detected by immunohistochemistry. The Fas and Fascin mRNA levels in tumor tissues from patients with GC were measured by real-time PCR and their correlation was analyzed.
RESULTS: The activation of Fas signaling promoted cell migration and resulted in STAT3-dependent Fascin upregulation in AGS cells. STAT3 enhanced Fascin levels in vivo. Fascin was the mediator of Fas signaling-induced AGS cell migration in vitro and in vivo. Furthermore, there was a positive correlation between Fas and Fascin mRNA levels in tumor tissues from GC patients.
CONCLUSIONS: Fas signaling promotes GC metastasis through the STAT3/Fascin pathway, which may provide a new target for GC therapy.
Single nucleotide polymorphisms (SNPs) in the promoter region of FAS and FASLG may alter their transcriptional activity. Thus, we determined the associations between four FAS and FASLG promoter variants (FAS1377G>A, rs2234767; 670A>G, rs1800682; FASLG844T>C, rs763110 and 124A>G, rs5030772) and the risk of recurrence of squamous cell carcinoma of the oropharynx (SCCOP). We evaluated the associations between FAS and FASLG genetic variants and the risk of recurrence in a cohort of 1,008 patients. The log-rank test and multivariate Cox models were used to evaluate the associations. Compared with patients with common homozygous genotypes of FAS670 and FASLG844 polymorphisms, patients with variant genotypes had lower disease-free survival rates (log-rank p < 0.0001 and p < 0.0001, respectively) and an approximately threefold higher risk of SCCOP recurrence (HR, 3.2;95% CI, 2.2-4.6; and HR, 3.1; 95% CI, 2.2-4.4, respectively) after multivariate adjustment. Furthermore, among patients with HPV16-positive tumors, those with variant genotypes of these two polymorphisms had lower disease-free survival rates (log-rank, p < 0.0001 and p < 0.0001, respectively) and a higher recurrence risk than did patients with common homozygous genotypes (HR, 12.9; 95% CI, 3.8-43.6; and HR, 8.1; 95% CI, 3.6-18.6, respectively), whereas no significant associations were found for FAS1377 and FASLG124 polymorphisms. Our findings suggest that FAS670 and FASLG844 polymorphisms modulate the risk of recurrence of SCCOP, particularly in patients with HPV16-positive tumors. Larger studies are needed to validate these results.
Daripally S, Nallapalle SR, Katta S, Prasad VVSusceptibility to oral cancers with CD95 and CD95L promoter SNPs may vary with the site and gender.
Tumour Biol. 2015; 36(10):7817-30 [PubMed
] Related Publications
We investigated risk association of oral cancers (tongue and buccal mucosa cancers) with FAS (-1377G > A and FAS -670 A > G) and FASL (-844 T > C) SNPs, in males and females. A case-control study of 535 oral cancer and 525 control subjects was performed. SNPs were detected in the genomic DNA isolated from peripheral blood using PCR-RFLP. We report FASL -844 T > C SNPs increased risk for buccal mucosa cancer in females but not in males. On the other hand, FAS genotypes did not alter the risk of the cancers in both females and males. However, co-occurrence of FAS -1377 GA and -670 GG, FAS -1377 AA and -670 GG genotypes, and combined genotypes of FAS and FASL (FAS -1377 AA + FAS -670 GG + FASL -844 CC) alter male susceptibility towards tongue cancer. In females, combined genotypes of FAS (-1377GA and -670 AA) were found to be a risk factor of buccal mucosa cancer (OR = 3.27, CI = 1.28-8.36; P ≤ 0.01). FASL variants (GA and AA) increased tongue cancer risk in females who were tobacco users compared to non-tobacco users. In conclusion, SNPs of the FAS and FASL might alter risk of tongue and buccal mucosa cancers differentially, in a gender-dependent manner.
Chen D, Li Y, Yu Z, et al.Downregulated microRNA-510-5p acts as a tumor suppressor in renal cell carcinoma.
Mol Med Rep. 2015; 12(2):3061-6 [PubMed
] Related Publications
MicroRNA (miR)-510-5p has been demonstrated to be involved in a number of types of malignancy; however, the function of miR-510-5p in renal cancer remains unclear. The present study aimed to determine the expression of miR-510-5p in renal cell carcinoma (RCC) specimens and analyzed the impact of miR-510-5p on renal cancer by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, wound scratch and apoptosis assays. The results showed that miR-510-5p was significantly downregulated in RCC specimens compared with normal renal specimens. Overexpression of miR-510-5p by synthetic mature mimics reduced cell proliferation and migration and induced an increase in cell apoptosis, indicating that miR-510-5p may act as a tumor suppressor in RCC. The present study firstly revealed that downregulated miR-510-5p functioned as a tumor suppressor by reducing cellular proliferation and migration, and inducing apoptosis in RCC. Further research is required to define target genes of miR-510-5p to determine the cellular mechanism of miR-510-5p in the carcinogenesis of RCC.
BACKGROUND: Patients with high-risk neuroblastoma (NBL) tumors have a high mortality rate. Consequently, there is an urgent need for the development of new treatments for this condition. Targeting death receptor signaling has been proposed as an alternative to standard chemo- and radio-therapies in various tumors. In NBL, this therapeutic strategy has been largely disregarded, possibly because ~50-70% of all human NBLs are characterized by caspase-8 silencing. However, the expression of caspase-8 is detected in a significant group of NBL patients, and they could therefore benefit from treatments that induce cell death through death receptor activation. Given that cytokines, such as TNFα, are able to upregulate Fas expression, we sought to address the therapeutic relevance of co-treatment with TNFα and FasL in NBL.
METHODS: For the purpose of the study we used a set of eight NBL cell lines. Here we explore the cell death induced by TNFα, FasL, cisplatin, and etoposide, or a combination thereof by Hoechst staining and calcein viability assay. Further assessment of the signaling pathways involved was performed by caspase activity assays and Western blot experiments. Characterization of Fas expression levels was achieved by qRT-PCR, cell surface biotinylation assays, and cytometry.
RESULTS: We have found that TNFα is able to increase FasL-induced cell death by a mechanism that involves the NF-κB-mediated induction of the Fas receptor. Moreover, TNFα sensitized NBL cells to DNA-damaging agents (i.e. cisplatin and etoposide) that induce the expression of FasL. Priming to FasL-, cisplatin-, and etoposide-induced cell death could only be achieved in NBLs that display TNFα-induced upregulation of Fas. Further analysis denotes that the high degree of heterogeneity between NBLs is also manifested in Fas expression and modulation thereof by TNFα.
CONCLUSIONS: In summary, our findings reveal that TNFα sensitizes NBL cells to FasL-induced cell death by NF-κB-mediated upregulation of Fas and unveil a new mechanism through which TNFα enhances the efficacy of currently used NBL treatments, cisplatin and etoposide.
Eun YG, Lee YC, Kim SK, et al.Single nucleotide polymorphisms of the Fas gene are associated with papillary thyroid cancer.
Auris Nasus Larynx. 2015; 42(4):326-31 [PubMed
] Related Publications
OBJECTIVES: Fas is the prototypic representative of the death receptor subgroup of the tumor necrosis factor (TNF) receptor family. Recently, single nucleotide polymorphisms (SNPs) of the Fas or Fas ligand (FasL) genes have been shown to be associated with an increased risk of several cancers and with the prognosis of several cancers. The objective of this study was to evaluate the association between the SNPs of the Fas and FasL genes and papillary thyroid cancer (PTC) and to assess the relationship between these SNPs and the clinicopathological characteristics of PTC.
METHODS: Five SNPs located within the two genes of Fas and FasL were genotyped using direct sequencing in 94 patients with PTC and 364 healthy controls. Genetic data were analyzed using commercially available software. And, the statistical analyses were performed according to clinicopathologic characteristics of PTC.
RESULTS: Genotyping analysis demonstrated that the intron SNP (rs1571013), promoter SNP (rs1800682) and 3'-UTR SNP (rs1468063) of Fas were significantly associated with the development of PTC. We also detected a significant difference between patients with PTC and healthy controls with respect to Fas gene allele frequencies. Furthermore, we found that the 3'-UTR SNP (rs1468063) of Fas was associated with the multifocality of cancer [dominant model, OR 0.28, p=0.028; log-additive model, OR 0.43, p=0.033].
CONCLUSION: We observed a significant association between SNPs of the Fas gene and the development of PTC. In addition, there was a significant association between a Fas SNP and the multifocality of PTC.
Singh NP, Abbas IK, Menard M, et al.Exposure to diethylstilbestrol during pregnancy modulates microRNA expression profile in mothers and fetuses reflecting oncogenic and immunological changes.
Mol Pharmacol. 2015; 87(5):842-54 [PubMed
] Free Access to Full Article Related Publications
Prenatal exposure to diethylstilbestrol (DES) is known to cause an increased susceptibility to a wide array of clinical disorders in humans. Previous studies from our laboratory demonstrated that prenatal exposure to DES induces thymic atrophy and apoptosis in the thymus. In the current study, we investigated if such effects on the thymus result from alterations in the expression of microRNA (miR). To that end, pregnant C57BL/6 mice who were exposed to DES and miR profiles in thymocytes of both the mother and fetuses on postnatal day 3 (gestation day 17) were studied. Of the 609 mouse miRs examined, we noted 59 altered miRs that were common for both mothers and fetuses, whereas 107 altered miRs were specific to mothers only and 101 altered miRs were specific to fetuses only. Upon further analyses in the fetuses, we observed that DES-mediated changes in miR expression may regulate genes involved in important functions, such as apoptosis, autophagy, toxicity, and cancer. Of the miRs that showed decreased expression following DES treatment, miR-18b and miR-23a were found to possess complementary sequences and binding affinity for 3' untranslated regions of the Fas ligand (FasL) and Fas, respectively. Transfection studies confirmed that DES-mediated downregulation of miR-18b and miR-23a led to increased FasL and Fas expression. These data demonstrated that prenatal DES exposure can cause alterations in miRs, leading to changes in the gene expression, specifically, miR-mediated increased expression in FasL and Fas causing apoptosis and thymic atrophy.
Bauer C, Hees C, Sterzik A, et al.Proapoptotic and antiapoptotic proteins of the Bcl-2 family regulate sensitivity of pancreatic cancer cells toward gemcitabine and T-cell-mediated cytotoxicity.
J Immunother. 2015; 38(3):116-26 [PubMed
] Related Publications
Sensitivity of carcinoma cells towards gemcitabine (Gem) has been linked to mitochondrial apoptotic proteins. Recently, we described synergistic efficacy of Gem-based chemoimmunotherapy and a dendritic cell (DC) tumor vaccine in a murine pancreatic carcinoma model. Here, we investigated the role of the mitochondrial proteins Bcl-2, Bcl-xL, and Bax for sensitization of pancreatic carcinoma cells toward T-cell-mediated cytotoxicity alone and in combination with Gem. Bcl-2 expression was silenced by siRNA in Panc02 pancreatic cancer cells expressing the model antigen ovalbumin (PancOVA). Tumor cells were treated with Gem and/or siRNA, and cytotoxicity induced by OVA-specific cytotoxic T lymphocytes (CTL) from OT-1 mice was assessed. Gem-induced and T-cell-induced cytotoxicity was also studied in human Colo357 pancreatic cancer cell lines overexpressing Bax or Bcl-xL. Apoptosis induction by Fas-activating antibody was measured by Annexin V staining. The in vivo capacity of Bcl-2 siRNA to augment CTL efficacy induced by DC vaccinations was assessed in C57BL/6 mice bearing PancOVA tumors. PancOVA cells treated with Bcl-2 siRNA were sensitized towards both Gem and T-cell-mediated killing; combination therapy exhibited an additive effect. Bax overexpression sensitized Colo357 cells to both Gem-mediated and T-cell-mediated cytotoxicity, whereas Bcl-xL overexpression was inhibitory. Combining Bcl-2 silencing with DC therapy improved tumor control in the PancOVA model in vivo without affecting the number of tumor-reactive CTL. In conclusion, expression of Bcl-2, Bcl-xL, and Bax in pancreatic tumor cells determines sensitivity towards both Gem-mediated and CTL-mediated toxicity. Bcl-2 silencing could be exploited therapeutically in tumor vaccine approaches.
BACKGROUND: The CD95 gene plays a key role in regulating cell growth and tumor genesis. To date, several publications have focused on the CD95 rs1800682A/G site polymorphism and various types of tumors in Asians; however, this association is still controversial and obscure. Therefore, a meta-analysis combined with all publications to clarify this association is necessary.
MATERIAL/METHODS: A search in the PubMed and SinoMed databases was performed to detect all relevant included publications. Odds ratio (OR) and 95% confidence intervals (CI) revealed association strengths.
RESULTS: Overall, 36 case-control studies were chosen based on the search criteria. There was no association of the CD95 rs1800682A/G site polymorphism with tumor risk in total and ethnicity subgroup analysis. However, further stratified analysis in the cancer subgroup revealed weakly significant associations in hepatocellular carcinoma (AA+AG vs. GG: OR=0.93, 95% CI=0.87-0.99, P=0.035; AG vs. GG: OR=0.89, 95% CI=0.80-0.99, P=0.036).
CONCLUSIONS: The CD95 rs1800682A/G site polymorphism may be associated with hepatocellular carcinoma susceptibility. Further large-scale and well-designed studies regarding tumor types and ethnicities are still required to confirm our results.
Ibeawuchi C, Schmidt H, Voss R, et al.Exploring prostate cancer genome reveals simultaneous losses of PTEN, FAS and PAPSS2 in patients with PSA recurrence after radical prostatectomy.
Int J Mol Sci. 2015; 16(2):3856-69 [PubMed
] Free Access to Full Article Related Publications
The multifocal nature of prostate cancer (PCa) creates a challenge to patients' outcome prediction and their clinical management. An approach that scrutinizes every cancer focus is needed in order to generate a comprehensive evaluation of the disease, and by correlating to patients' clinico-pathological information, specific prognostic biomarker can be identified. Our study utilized the Affymetrix SNP 6.0 Genome-wide assay to investigate forty-three fresh frozen PCa tissue foci from twenty-three patients. With a long clinical follow-up period that ranged from 2.0-9.7 (mean 5.4) years, copy number variation (CNV) data was evaluated for association with patients' PSA status during follow-up. From our results, the loss of unique genes on 10q23.31 and 10q23.2-10q23.31 were identified to be significantly associated to PSA recurrence (p < 0.05). The implication of PTEN and FAS loss (10q23.31) support previous reports due to their critical roles in prostate carcinogenesis. Furthermore, we hypothesize that the PAPSS2 gene (10q23.2-10q23.31) may be functionally relevant in post-operative PSA recurrence because of its reported role in androgen biosynthesis. It is suggestive that the loss of the susceptible region on chromosome 10q, which implicates PTEN, FAS and PAPSS2 may serve as genetic predictors of PSA recurrence after radical prostatectomy.
Zhu H, Berkova Z, Mathur R, et al.HuR Suppresses Fas Expression and Correlates with Patient Outcome in Liver Cancer.
Mol Cancer Res. 2015; 13(5):809-18 [PubMed
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UNLABELLED: Hepatocellular carcinomas (HCC) show resistance to chemotherapy and have blunt response to apoptotic stimuli. HCC cell lines express low levels of the Fas death receptor and are resistant to FasL stimulation, whereas immortalized hepatocytes are sensitive. The variable Fas transcript levels and consistently low Fas protein in HCC cells suggest posttranscriptional regulation of Fas expression. The 3'-untranslated region (UTR) of Fas mRNA was found to interact with the ribonucleoprotein Human Antigen R (HuR) to block mRNA translation. Silencing of HuR in HCC cells increased the levels of cell surface Fas and sensitized HCC cells to FasL. Two AU-rich domains within the 3'-UTR of Fas mRNA were identified as putative HuR-binding sites and were found to mediate the translational regulation in reporter assay. Hydrodynamic transfection of HuR plasmid into mice induced downregulation of Fas expression in livers and established functional resistance to the killing effects of Fas agonist. Human HCC tumor tissues showed significantly higher overall and cytoplasmic HuR staining compared with normal liver tissues, and the high HuR staining score correlated with worse survival of patients with early-stage HCC. Combined, the protumorigenic ribonucleoprotein HuR blocks the translation of Fas mRNA and effectively prevents Fas-mediated apoptosis in HCC, suggesting that targeting HuR would sensitize cells to apoptotic stimuli and reverse tumorigenic properties.
IMPLICATIONS: Demonstrating how death receptor signaling pathways are altered during progression of HCC will enable the development of better methods to restore this potent apoptosis mechanism.
Resistance toward CD95-mediated apoptosis is a hallmark of many different malignancies, as it is known from primary chronic lymphocytic leukemia (CLL) cells. Previously, we could show that miR-138 and -424 are downregulated in CLL cells. Here, we identified 2 new target genes, namely acyl protein thioesterase (APT) 1 and 2, which are under control of both miRs and thereby significantly overexpressed in CLL cells. APTs are the only enzymes known to promote depalmitoylation. Indeed, membrane proteins are significantly less palmitoylated in CLL cells compared with normal B cells. We identified APTs to directly interact with CD95 to promote depalmitoylation, thus impairing apoptosis mediated through CD95. Specific inhibition of APTs by siRNAs, treatment with miRs-138/-424, and pharmacologic approaches restore CD95-mediated apoptosis in CLL cells and other cancer cells, pointing to an important regulatory role of APTs in CD95 apoptosis. The identification of the depalmitoylation reaction of CD95 by APTs as a microRNA (miRNA) target provides a novel molecular mechanism for how malignant cells escape from CD95-mediated apoptosis. Here, we introduce palmitoylation as a novel posttranslational modification in CLL, which might impact on localization, mobility, and function of molecules, survival signaling, and migration.
Using miRNA microarray analysis, we identified 31 miRNAs that were significantly up-regulated or down-regulated in colon cancer tissues. We chose MIR196B, which was specifically up-regulated in colon cancer, for further study. We identified 18 putative MIR196B target genes by comparing between the mRNAs down-regulated in MIR196B-overexpressed cells and the assumed MIR196B target genes predicted by public bioinformatics tools. The association between MIR196B and FAS was verified in this study. FAS expression was constitutively elevated in normal human colorectal tissues. However, its expression was often reduced in human colorectal cancer. The decrease in FAS expression could be responsible for the reduction of apoptosis in colorectal cancer cells. In colorectal cancer tissue, we showed that MIR196B up-regulation was mutually followed by down regulation of FAS expression. We also showed that MIR196B directly repressed FAS expression in colorectal cells. Furthermore, anti-MIR196B up-regulated FAS expression and increased apoptosis in colorectal cancer cell lines. Our results suggest that the up-regulation of MIR196B modulates apoptosis in colorectal cancer cells by partially repressing FAS expression and that anti-MIR196B could be a potential candidate as an anti-cancer drug in colorectal cancer therapy.
Apoptosis is an important mechanism of malignant tumor formation and progression. Single nucleotide polymorphisms (SNPs) located within cell death genes may influence cancer risk. We explored the relationship between FasL -844T/C and/or Fas -1377G/A SNPs and pulmonary adenocarcinoma (AD). Two hundred seventy-five patients with pulmonary AD of South China admitted into Zhejiang Cancer Hospital from July 2007 to October 2011 were randomly selected, and their clinicopathological data were collected at the same time. Two hundred ninety-seven cases of healthy individuals were selected as control. FasL -844T/C and Fas -1377G/A SNPs were detected by PCR-RFLP technique to evaluate the relationships between these two SNPs and pulmonary AD. Age, FasL -844 and Fas -1377 SNPs were associated with increased risk of pulmonary AD susceptibility in main effect analysis. FasL -844CC and Fas -1377 AA were associated with an increased risk for the development of pulmonary AD only in age <60 years people, but not in those ≥60 years. FasL -844CC genotype was associated with an increased risk for pulmonary AD (adjusted OR = 2.010, 95 % CI 1.196-3.379, P = 0.008) compared with TT genotype. However, Fas -1377 AA was a risk factor only when FasL -844 genotype was CC. Fas -1377 genotypes showed significant effect modification of pulmonary AD risk by FasL -844 genotype with test of the interaction term adjusting for age, gender, and FasL -844 SNP. Fas -1377G/A was not associated with the clinicopathological factors, while FasL -844C/T was associated with tumor stage and lymph node metastasis in age ≥60 years people and tumor stage in those <60 years. In conclusion, FasL -844 SNP is associated with the susceptibility of pulmonary AD in age <60 years people. Fas -1377 SNP may modify the association of FasL -844 SNP with the risk of pulmonary AD. FasL -844 genotype plays an important role in the occurrence and progression of pulmonary AD.
Esmailzadeh S, Huang Y, Su MW, et al.BIN1 tumor suppressor regulates Fas/Fas ligand-mediated apoptosis through c-FLIP in cutaneous T-cell lymphoma.
Leukemia. 2015; 29(6):1402-13 [PubMed
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The bridging integrator 1 (BIN1) tumor suppressor encodes multiple alternatively spliced isoforms implicated in DNA repair, cell-cycle control, apoptosis and membrane dynamics. BIN1 attenuation has been reported in several solid tumors; however, the role of BIN1 in lymphomagenesis remains unexplored. We recently demonstrated that BIN1 transcript levels are significantly downregulated in CD4(+)CD7(-) Sezary cells from patients with Sezary syndrome (SS), a subtype of cutaneous T-cell lymphoma (CTCL). We have now demonstrated that restored BIN1 expression in CTCL cells leads to a significant reduction in cell proliferation, an increase in spontaneous and Fas/Fas ligand (Fas/FasL)-induced apoptosis in vitro and inhibition of tumorigenic activity of CTCL cells in vivo. Interestingly, restoration of BIN1 expression in CTCL cells downregulates the expression of c-FLIP, an important inhibitor of Fas/FasL-mediated apoptosis, and activates the caspase cascade; these phenotypes can be rescued by knockdown of BIN1. Importantly, significantly reduced BIN1 expression and increased c-FLIP expression are observed in primary CTCL patient samples, and high BIN1 and low c-FLIP mRNA levels correlate with better survival rate in SS patients. These results indicate that BIN1 regulates Fas/FasL-mediated apoptosis through c-FLIP and that BIN1 deficiency may have an important role in CTCL pathogenesis by causing apoptosis resistance. Thus BIN1 and c-FLIP represent potential therapeutic targets in CTCL.