TITLE:
Study of Vitamin D Receptor (VDR) Gene Polymorphisms among Egyptian Cohort Patients with Different Stages of Colorectal Cancer
AUTHORS:
Mohamed M. Rizk, Nermine H. Zakaria, Waleed G. Elshazely
KEYWORDS:
Vitamin D Receptor (VDR); Colorectal Cancer (CRC); PCR-RFLP (Polymorphism)
JOURNAL NAME:
Journal of Cancer Therapy,
Vol.5 No.3,
March
19,
2014
ABSTRACT: Colorectal cancer represents the third cancer
worldwide. Studies showed thatinsufficient
levels of vitamin D may result in colorectal cancer. Genetic variations in
genes controlling vitamin D activity would play a role in determining
susceptibility to colorectal cancer. Aim of the work: to study
the different genotypes of VDR polymorphisms and detect the association between
serum levels of 25(OH)VitD and 1,25(OH)2VitD among sample of Egyptian patients
with different stages of colorectal cancer. Methods: Ninety patients (60 with
different stages of colorectal cancer and 30 patients with benign pathology of
the colon) together with 30 healthy controls were examined using PCR-RFLP
analysis for FokI, ApaI and TaqI polymorphisms. Results: Genotype distribution
for ApaI polymorphism showed no statistically significant
difference between patients (colorectal cancer and benign) and controls with p
= 0.1. There was no statistically significant difference in FokI
polymorphism where p = 0.26 and
genotype distribution for TaqI was also insignificant with p = 0.016.
The median serum level of 25(OH)VitD was low in cancer cases compared to the
control group and benign cases with (p 0.001). There was no statisticallysignificant
difference of median serum level of 1,25(OH)2VitD between benign and cancer
cases. There was statistically
significant difference of median serum level of 25(OH)VitD and 1,25(OH)2VitD
between stage I and stage II with (p = 0.004) and (p 0.001), and between stage I and stage III with
(p = 0.001)and (p 0.001),
but no statistically significant difference between stage II and III with (p = 0.514).
Conclusions: There is ethnic variability in vitamin D receptor gene
polymorphisms. The lack of significant association of the studied gene polymorphism in
our population suggests that its association with other functionally known gene
polymorphism might have a role in the pathogenesis of colorectal cancer.