Polymorphism of interleukin-6 -174 G/C (rs1800795) & the corresponding interleukin-6 level as a prognostic marker of cervical cancer

BACKGROUND & OBJECTIVES: Aetiology of cervical cancer (CaCx) is multifactorial. Besides human papillomavirus (HPV) infection, many immunogenetic factors are involved in this complex process. The present study was carried out to investigate one such factor, interleukin-6 (IL-6), a central pro-inflammatory cytokine and a polymorphism at its promoter region -174 G/C (rs1800795) with CaCx. METHODS: HPV-infected women with or without CaCx were enrolled in group I and II, respectively. Another group of uninfected healthy women was also included as group III for comparison. Polymorphism in IL-6-174 G/C and IL-6 levels were analyzed by sequence-specific primer PCR (PCR-SSP) and ELISA, respectively. RESULTS: Groups I (n=111) and II (n=87) had significantly higher frequency of IL-6-174 GG genotype [odds ratios (OR)=3.9; P<0.001 and OR=3.2; P<0.001, respectively] as compared to group III (n=163). Furthermore, individuals with GG or GC genotypes had high IL-6 levels than those with CC genotypes. IL-6 levels were significantly (P<0.001) elevated in group I. This was also significantly high in untreated cases as compared to treated (P<0.05) ones. IL-6 levels of treated group were comparable with groups II and III. INTERPRETATION & CONCLUSIONS: Our results suggested a possible association of IL-6-174 GG with CaCx, which was also associated with high IL-6 levels. Decreased levels of IL-6 following treatment indicate its possible prognostic use in CaCx cases.