Cytokine gene polymorphisms and their association with cervical cancer: A North Indian study
Introduction: The production of cytokines, growth factors and adhesion molecules promotes tumor progression and involves inflammation, angiogenesis and thrombosis, thus providing optimal conditions for cancer development.
Materials and methods: The present study was undertaken to evaluate association of cytokine gene polymorphisms with cervical cancer in a north Indian population. Genotyping of single nucleotide polymorphisms (SNPs) viz. IL 6-597G/A (rs1800797), IL-1b-511C/T (rs16944) and TNF-a-308G/A (rs1800629) was carried out in 100 each of cases and healthy age matched controls by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP). Genotype and allele frequencies were calculated by SPSS (ver.16) and gene–gene interaction was analyzed using SHEsis (ver. Online).
Results: Epidemiological studies showed that women >40 years have higher risk of cervical cancer due to early pregnancies. IL-6 and TNF-a promoter polymorphisms showed significant association (P < 0.001) while the SNP combinations G A T* and G G T* of IL-6-597A/G, TNF-a-308G/A and IL-1b-511C/T polymorphisms showed increased risk up to 9.0 and 3.30 times respectively.
Conclusion: Therefore, the promoter polymorphisms in cytokine genes can be used as biomarkers to predict cervical cancer susceptibility in a north Indian population. However, such studies need to be carried out in different ethnic populations in order to discover the specific risk alleles, genotypes and combinations for disease prediction.
Keywords: Cervical cancer; SNP; Association; IL-6; IL-1b; TNF-a