A literature-based systematic HuGE review and meta-analysis show that CASP gene family polymorphisms are associated with risk of lung cancer

Association of genetic polymorphisms in CASP7 with risk of ischaemic stroke

Caspase 7 (CASP7) is located on chromosome 10q25.3 that has been identified to be a susceptibility locus of ischaemic stroke (IS) by genome-wide association study. Elevated CASP7 was observed in IS, acting as a key apoptotic mediator in the development of IS. The aim of this study was to investigate the association between genetic polymorphisms in CASP7 and risk of IS. The CASP7 polymorphisms were genotyped using a TaqMan allelic discrimination assay. The expression levels of CASP7 mRNA were examined using quantitative polymerase chain reaction and luciferase activity was analyzed using the Dual Luciferase reporter assay. The rs12415607 in the promoter of CASP7 was associated with a reduced risk of IS (AA vs. CC: adjusted OR = 0.55, 95% CI: 0.38-0.80, P = 0.002; CA/AA vs. CC: adjusted OR = 0.70, 95% CI: 0.54-0.91, P = 0.007; AA vs. CC/CA: adjusted OR = 0.64, 95% CI: 0.46-0.90, P = 0.01; A vs. C: adjusted OR = 0.74, 95% CI: 0.62-0.89, P = 0.001). Moreover, the rs12415607 AA genotype carriers exhibited lower levels of CASP7 mRNA and the rs12415607 A allele decreased the promoter activity. These findings indicate that the rs12415607 A allele induces lower levels of transcriptional activity and CASP7 mRNA, and thus is associated with a reduced risk of IS.

A meta-analysis of caspase-8 -652 6N del polymorphism and digestive tract cancer risk

Caspase-8 (CASP8) is one key regulator of apoptosis of T lymphocytes and is encoded by the CASP8 gene. It has been reported that the six-nucleotide deletion polymorphism (-652 6N del) of the CASP8 gene had effect on some cancer risk. Few studies explored the association between CASP8 gene polymorphism and digestive tract cancer risk. To evaluate the association between the CASP8 -652 6N del polymorphism and the risk of digestive tract cancer, we conducted this meta-analysis. We found that CASP8-652 6N del polymorphism was associated with a significantly reduced risk of digestive tract cancer in the co-dominant model (del/del vs. ins/ins: OR= 0.82, 95%CI= 0.72-0.95; del/ins vs. ins/ins: OR= 0.92, 95%CI= 0.87-0.97; dominant model (del/ins+ del/del vs. ins/ins: OR= 0.91, 95%CI= 0.87-0.96, recessive model: del/del vs. del/ins+ ins/ins: OR= 0.85, 95%CI= 0.75-0.97). In the stratified analysis by cancer types, we found that all genetic models had protective effect on gastric cancer. Similar results were observed for colorectal cancer under heterozygote comparison and dominant model, but not under homozygote comparison or recessive model. In addition, a significantly decreased risk was found on esophageal cancer for most genetic models, except heterozygote comparison. When stratified by ethnicity and source of control, an evidently decreased risk was identified in the Asian populations and population-based studies. In conclusion, there exists an association between the CASP8 -652 6N del polymorphism and reduced digestive cancer risk, especially among Asians and population-based studies.

Individual and combined effect of TP53, MDM2, MDM4, MTHFR, CCR5, and CASP8 gene polymorphisms in lung cancer

Lung cancer (LC) is the second common and with the highest mortality oncological disease. Specific biomarkers for its diagnostics, treatment, and prognosis are still under the investigations. Aim of our study was to evaluate the relationship between the polymorphisms of TP53 pathway genes TP53, MDM2, MDM4, the polymorphisms of HPV-associated genes MTHFR, CASP8, CCR5, and HPV infection with survival of LC patients. SNPs were genotyped using PCR-RFLP. qRT-PCR was used to detect, identify, and quantify HPV. No statistically significant differences were detected between individual SNPs and patient survival with stage I-IV LC. Cluster analysis of SNPs in genes MDM4 A/A, CCR5 wt/Δ32, MTHFR C/T, MDM2 T/T showed possible association with the worse survival. Patients who were diagnosed with C/T polymorphic variant of gene MTHFR tend not to survive stage III-IV LC (P = .12). There is a tendency between MDM2 gene T/T variant and worse survival of patients diagnosed with late stage LC (P = .11). HPV infection is very rear among LC patients (3 of 92). Overall, there is a link, although statistically insignificant, between specific SNPs and LC patient survival frequency and time, meanwhile the combination of specific SNPs showed a statistically significant measure. In conclusion, we determined statistically significant (P = .04) link between the poor survival of LC patients after surgery and the combination of polymorphic variants C/T of the MTHFR and T/T of the MDM2 genes, whereas individually these SNPs do not show significant relationship with the survival of patients after surgery.