Functional polymorphisms in FAS and FASL contribute to risk of squamous cell carcinoma of the larynx and hypopharynx in a Chinese population

The Anti-tumor Activity and Mechanisms of rLj-RGD3 on Human Laryngeal Squamous Carcinoma Hep2 Cells

BACKGROUND

Laryngeal Squamous Cell Carcinoma (LSCC) is a malignant epithelial tumor with poor prognosis and its incidence rate increased recently. rLj-RGD3, a recombinant protein cloned from the buccal gland of Lampetra japonica, contains three RGD motifs that could bind to integrins on the tumor cells.

METHODS

MTT assay was used to detect the inhibitory rate of viability. Giemsa's staining assay was used to observe the morphological changes of cells. Hoechst 33258 and TUNEL staining assay, DNA ladder assay were used to examine the apoptotic. Western blot assay was applied to detect the change of the integrin signal pathway. Wound-healing assay, migration, and invasion assay were used to detect the mobility of Hep2 cells. H&E staining assay was used to show the arrangement of the Hep2 cells in the solid tumor tissues.

RESULTS

In the present study, rLj-RGD3 was shown to inhibit the viability of LSCC Hep2 cells in vitro by inducing apoptosis with an IC50 of 1.23µM. Western blot showed that the apoptosis of Hep2 cells induced by rLj- RGD3 was dependent on the integrin-FAK-Akt pathway. Wound healing, transwells, and western blot assays in vitro showed that rLj-RGD3 suppressed the migration and invasion of Hep2 cells by integrin-FAKpaxillin/ PLC pathway which could also affect the cytoskeleton arrangement in Hep2 cells. In in vivo studies, rLj-RGD3 inhibited the growth, tumor volume, and weight, as well as disturbed the tissue structure of the solid tumors in xenograft models of BALB/c nude mice without reducing their body weights.

CONCLUSION

These results suggested that rLj-RGD3 is an effective and safe suppressor on the growth and metastasis of LSCC Hep2 cells from both in vitro and in vivo experiments. rLj-RGD3 might be expected to become a novel anti-tumor drug to treat LSCC patients in the near future.

Quantitative assessment of the relationship between Fas/FasL genes polymorphisms and head and neck cancer risk

BACKGROUND

Molecular epidemiological studies have demonstrated a closer association between Fas/FasL polymorphisms and head and neck cancer (HNC) risk, and the results of these published studies were inconsistent. We therefore performed this meta-analysis to explore the associations between Fas/FasL polymorphisms and HNC risk.

METHODS

Four online databases (PubMed, Embase, CNKI, and Wanfang) were searched. Odds ratios (ORs) with 95% confidence interval (95% CIs) were calculated to assess the association between Fas -670A>G, Fas -1377G>A, and FasL -844C>T polymorphisms and HNC risk. In addition, heterogeneity, accumulative/sensitivity analysis, and publication bias were conducted to check the statistical power.

RESULTS

Overall, 9 related publications (20 independent case-control studies) involving 3179 patients and 4217 controls were identified. Significant association of protective effects was observed between FasL -844C>T polymorphism and HNC risk in codominant and dominant model models (CT vs CC: OR = 0.89, 95% CI = 0.79-1.00, P = .05, I = 38.3%, CT+TT vs CC: OR = 0.88, 95% CI = 0.79-0.98, P = .02, I = 35.8%). Furthermore, the similar protective effects were observed the subgroup analysis of in Asian population and population-based controls group.

CONCLUSION

Our meta-analysis indicated that FasL -844C>T polymorphism plays a protective role against HNC development, but the Fas -670A>G and Fas -1377G>A polymorphisms maybe not associated with HNC risk.

Fas-670A>G polymorphism is not associated with an increased risk of acute myeloid leukemia development

The association between the increased risk of acute myeloid leukemia (AML) and Fas promoter polymorphisms has been reported previously; however, the results are inconclusive. The present study performed one case-control study to investigate the association, and a total of 98 AML patients and 2,014 healthy controls were genotyped. The data showed that the distribution of Fas-670AA, GA and GG genotypes among the AML patients were not significantly different from those of the healthy controls, all P>0.05. Following this a sub-study was conducted to analyze individuals who neither smoked nor drank. The results demonstrated that there was still no significant association between the Fas-670 polymorphism and risk of AML development, all P>0.05. Furthermore, in order to address a more accurate estimation of the association, a meta-analysis was conducted. Data were systematically collected from the Pubmed, EMBASE and the Wanfang Library. A total of 3 studies were included in this meta-analysis, which contained 1,144 AML cases and 3,806 controls. No significant association was detected between the Fas-670A>G polymorphism and AML risk [GA+GG vs. AA: odds ratio (OR) 0.93; 95% confidence interval (CI), 0.79–1.09; GG vs. AA: OR, 1.01; 95% CI, 0.82–1.24; GA vs. AA: OR, 1.12; 95% CI, 0.94–1.32; GG vs. AA+GA: OR, 0.94; 95% CI, 0.79–1.12; G vs. A: OR, 1.01; 95% CI, 0.91–1.12; all P>0.05). The analysis clearly indicated that there was no significant connection between the Fas-670A>G polymorphism and the increased risk of AML.

Site disparities in apoptotic variants as predictors of risk for second primary malignancy in patients with squamous cell carcinoma of the head and neck

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.

Sildenafil (Viagra) sensitizes prostate cancer cells to doxorubicin-mediated apoptosis through CD95

We previously reported that Sildenafil enhances apoptosis and antitumor efficacy of doxorubicin (DOX) while attenuating its cardiotoxic effect in prostate cancer. In the present study, we investigated the mechanism by which sildenafil sensitizes DOX in killing of prostate cancer (PCa) cells, DU145. The death receptor Fas (APO-1 or CD95) induces apoptosis in many carcinoma cells, which is negatively regulated by anti-apoptotic molecules such as FLIP (Fas-associated death domain (FADD) interleukin-1-converting enzyme (FLICE)-like inhibitory protein). Co-treatment of PCa cells with sildenafil and DOX for 48 hours showed reduced expression of both long and short forms of FLIP (FLIP-L and -S) as compared to individual drug treatment. Over-expression of FLIP-s with an adenoviral vector attentuated the enhanced cell-killing effect of DOX and sildenafil. Colony formation assays also confirmed that FLIP-S over-expression inhibited the DOX and sildenafil-induced synergistic killing effect as compared to the cells infected with an empty vector. Moreover, siRNA knock-down of CD95 abolished the effect of sildenafil in enhancing DOX lethality in cells, but had no effect on cell killing after treatment with a single agent. Sildenafil co-treatment with DOX inhibited DOX-induced NF-κB activity by reducing phosphorylation of IκB and nuclear translocation of the p65 subunit, in addition to down regulation of FAP-1 (Fas associated phosphatase-1, a known inhibitor of CD95-mediated apoptosis) expression. This data provides evidence that the CD95 is a key regulator of sildenafil and DOX mediated enhanced cell death in prostate cancer.

Single nucleotide polymorphisms of the Fas gene are associated with papillary thyroid cancer

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.

CD95 rs1800682A/G variant and tumor risk in Asians: evidence from a meta-analysis of 36 case-control studies containing 22,438 samples

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.

Pilot Investigation of the Association Between Serum Stress Neuropeptide Levels and Lymphocyte Expression of Fas and Fas Ligand in Critical Illness

Introduction:

In critical illness, apoptotic loss of immunocytes is associated with immunosuppression.

Aim:

To explore expression of Fas/Fas ligand (FasL) on B and T cells from critically ill patients without sepsis compared to matched controls and associations with disease severity and neuropeptide Y (NPY), cortisol, adrenocorticotropic hormone (ACTH), and prolactin (PRL) levels.

Methods:

Repeated-measures correlational design with 36 critically ill patients (14-day follow-up) and 36 controls. Disease severity was assessed using the Multiple Organ Dysfunction Score (MODS) and Multi Organ Failure scale. Fas/FasL values were standardized for viable cell counts. An enzyme-linked immunosorbent assay (NPY) and electrochemiluminescence immunoassay (cortisol, ACTH, and PRL) were employed.

Results:

Fas and FasL expression on T-helper ( p < .0001–.03) and T-cytotoxic cells ( p < .0001–.002) and Fas expression on B cells ( p < .0001–.03) were higher in patients. MODS severity was associated with FasL expression on cytotoxic T cells ( r = .752–.902, p = .023–.037). There was an inverse association between Day 1 NPY levels and Fas expression on T-helper cells ( r = −.447, p = .019). On the day of maximum severity, we report for the first time an inverse association between NPY levels and FasL expression on helper ( r = −.733, p = .016) and cytotoxic ( r = −.862, p = .003) T cells. Cortisol levels were positively associated with counts of FasL-positive helper ( r = .828) and cytotoxic ( r = .544, p < .05) T cells.

Conclusion:

Results suggest a potential role for stress neuropeptides in lymphocyte survival and activation in critical illness.

GSTT1 polymorphism and the risk of developing prostate cancer

A possible association between glutathione S-transferase theta 1 gene (GSTT1) polymorphism and the risk of developing prostate cancer is currently hotly debated, but evidence from various epidemiologic studies remains unclear. This investigation was performed to assess whether an association between GSTT1 polymorphism and prostate cancer risk exists by using meta-analysis to combine comparable studies, thereby increasing sample size and statistical significance, as well as to identify patterns in various studies. The association reports were identified from the PubMed database and the Cochrane Library on March 1, 2013, and data from eligible studies (from 1999-2012) were synthesized. Thirty-eight reports were included in this meta-analysis on the association of the null genotype of GSTT1 with prostate cancer risk. No solid association between the GSTT1 null genotype and prostate cancer risk could be established for the overall population (odds ratio = 1.11, 95% confidence interval: 0.97, 1.27; P = 0.13). However, the GSTT1 null genotype was distinctly associated with prostate cancer risk in Caucasians (odds ratio = 1.24, 95% confidence interval: 1.03, 1.48, P = 0.02). In conclusion, the GSTT1 null genotype is associated with prostate cancer risk in Caucasians, but not in the overall population.

Association between the FAS rs2234767G/A polymorphism and cancer risk: a systematic review and meta-analysis

Abnormal regulation of apoptosis can lead to carcinogenesis. Single nucleotide polymorphisms in apoptotic genes have been associated with cancer risk, such as the FAS rs2234767G/A polymorphism, which alters transcription of the FAS promoter. Downregulation of FAS, with resultant cellular resistance to death signals, has been found in many cancers. However, the association between the FAS rs2234767G/A polymorphism and cancer risk is still controversial. Here, we performed a meta-analysis including 41 articles (44 case-control studies, 17,814 cases and 24,307 controls) identified from PubMed and Chinese language (CNKI and WanFang) databases related to cancer susceptibility and the FAS rs2234767G/A polymorphism. We used odds ratios (ORs) and 95% confidence intervals (CIs) to assess the strength of the associations. We found that the rs2234767 G-allele was a protective factor for cancer risk (GG vs. AA: OR=0.88, 95% CI=0.79-0.98; GG+GA vs. AA: OR=0.87, 95% CI=0.79-0.96). Similar associations were detected in the "source of control", ethnicity, and cancer type subgroups. Further studies on a larger sample size and considering gene-environment interactions should be conducted to confirm the role of FAS polymorphisms, especially rs2234767G/A, in cancer risk.

Association of single nucleotide polymorphisms of nucleotide excision repair genes with laryngeal cancer risk and interaction with cigarette smoking and alcohol drinking

We investigated the potential association of 12 single nucleotide polymorphisms (SNPs) of nucleotide excision repair (NER) genes with risk of laryngeal cancer. A ratio of 1:1 matched case-control study was conducted. Conditional regression analysis indicated that subjects with ERCC1 rs11615 CC and C allele had an increased risk of laryngeal cancer compared with the TT genotype. Individuals with the ERCC5 rs17655 GG and G allele had a moderately increased risk of laryngeal cancer when compared with the CC genotype. By stratified analysis, ERCC1 rs11615 CC genotype and C allele were significantly associated with greatly increased risk of laryngeal cancer in ever smokers. ERCC1 rs11615 and ERCC5 rs17655 polymorphisms were associated with a moderately increased risk of this cancer in ever drinkers. In summary, we suggest that genetic variations in ERCC1 rs11615 and ERCC5 rs17655 are associated with laryngeal cancer risk in a Chinese population, especially in ever smokers and drinkers. Our finding could be helpful in identifying people at high risk for the disease for early intervention.

Association of C722T polymorphism in XRCC3 gene with larynx cancer: a meta-analysis

Several case-control studies indicated that XRCC3 genetic polymorphism (C722T) was associated with larynx cancer. The present study aimed to further evaluate the relation between the XRCC3 gene C722T polymorphism and larynx cancer. We selected five case-control studies related to XRCC3 gene C722T polymorphism and larynx cancer by searching PubMed, EMBase, Chinese CNKI, and Wanfang database. RevMan 5.0 software was used to perform the analysis. We directly utilized Q test and I (2) test to test the heterogeneity between each study. We utilized the fixed effects model to merge the odds ratio (OR) and 95 % confidence interval. There were 1,507 larynx cancer patients and 3,623 cancer-free control subjects included in the present study. By meta-analysis, we did not find any association of XRCC3 gene C722T polymorphism with larynx cancer [OR=1.54, 95 % CI (0.77-3.08); P=0.22]. The present study indicated that XRCC3 gene C722T polymorphism was not associated with larynx cancer.

Association of XRCC1 genetic polymorphism (Arg399Gln) with laryngeal cancer: a meta-analysis based on 4,031 subjects

Several case-control studies on the relation between XRCC1 gene Arg399Gln polymorphism and laryngeal cancer do not have similar conclusions. To further evaluate the relation between the XRCC1 gene Arg399Gln polymorphism and laryngeal cancer, we selected seven case-control studies related to the XRCC1 gene Arg399Gln polymorphism and laryngeal cancer by searching MEDLINE, EMBase, Chinese Biomedical Literature Database, Chinese CNKI, and Wanfang database. We utilized Q test and I (2) test to test the heterogeneity between each study. The fixed effects model was utilized to calculate the odds ratio (OR) and 95 % confidence interval. The present study included 1,654 patients with laryngeal cancer and 2,377 cancer-free control subjects. By meta-analysis, we did not find any association of XRCC1 gene Arg399Gln polymorphism with laryngeal cancer (OR = 1.13, 95 % CI 0.81-1.58, P = 0.47). Therefore, we concluded that XRCC1 gene Arg399Gln polymorphism was not associated with laryngeal cancer.

FASL rs763110 polymorphism contributes to cancer risk: an updated meta-analysis involving 43,295 subjects

Background

Published studies investigating the association between genetic polymorphism -884C/T (rs763110) of the FAS ligand (FASL) promoter and cancer risk reported inconclusive results. To derive a more precise estimation of the relationship, we performed an updated meta-analysis of all eligible studies.

Methodology/Principal Findings

We carried out a meta-analysis, including 47 studies with 19,810 cases and 23,485 controls, to confirm a more conclusive association between the FASL rs763110 polymorphism and cancer susceptibility. Overall, significantly reduced cancer risk was associated with the variant -884T when all studies were pooled (TC vs. CC: OR = 0.83, 95%CI = 0.75–0.92; P_{heterogeneity}<0.001; TT+TC vs. CC: OR = 0.85, 95%CI = 0.77–0.94; P_{heterogeneity}<0.001). Stratified analysis revealed that there was a statistically reduced cancer risk in Asians (TC vs. CC: OR = 0.76, 95%CI = 0.67–0.87; P_{heterogeneity}<0.001; TT+TC vs. CC: OR = 0.79, 95%CI = 0.70–0.90; P_{heterogeneity}<0.001) and in patients with cancers of head and neck (TC vs. CC: OR = 0.87, 95%CI = 0.77–0.99; P_{heterogeneity} = 0.118; TT+TC vs. CC: OR = 0.88, 95%CI = 0.78–0.99; P_{heterogeneity} = 0.168) and ovarian cancer (TC vs. CC: OR = 0.67, 95%CI = 0.49–0.90; P_{heterogeneity} = 0.187; TT+TC vs. CC: OR = 0.64, 95%CI = 0.48–0.86; P_{heterogeneity} = 0.199). Meta-regression showed that ethnicity (p = 0.029) and genotyping method (p = 0.043) but not cancer types (p = 0.772), sample size (p = 0.518), or source of controls (p = 0.826) were the source of heterogeneity in heterozygote comparison.

Conclusion

Our results suggest that the FASL polymorphism rs763110 is associated with a significantly reduced risk of cancer, especially in Asian populations.