Association between VDR (Fok1) Polymorphism and Cervical Cancer Risk among Women in Northeastern Thailand

Abstract

Fok1 is a vitamin D receptor gene that located in chromosome 12 (12q13.11). This gene plays a crucial role in inhibition of cell proliferation and angiogenesis, in addition, promotes cell differentiation and apoptosis of cancer cells. There are three genotypes of the Fok1 including CC, CT and TT genotypes. Individuals with each genotype might contribute a risk of cancer development differently. Therefore, the purpose of this study was to investigate the association between Fok1 polymorphism and cervical cancer risk in Northeastern Thai women. The subjects were divided into two groups: control group (n=184) and cervical cancer group (n=184). Genomic DNA was extracted from peripheral blood leukocytes and analyzed for Fok1 polymorphism by real-time polymerase chain reaction (PCR) with TaqMan Probe. No significant association between Fok1 polymorphism and the risk for cervical cancer was observed. However, among women with smoking partners who carried TT genotype had a 0.52-fold (95%Cl = 0.26-1.04, p = 0.046) lower risk for cervical cancer as compared with those carried CC genotype. In addition, among women who used oral contraceptives that carried CT genotype had a 0.34-fold (95%Cl = 0.14-0.83, p = 0.018) lower risk for cervical cancer as compared with those carried CC genotype. In conclusion, the genetic polymorphism of Fok1 is associated with risk for cervical cancer development among who had smoking partner and oral contraceptive user.