Associations of vitamin D receptor encoding gene variants with premenopausal breast cancer risk

OBJECTIVE

This study evaluates whether vitamin D receptor (VDR) gene variations are associated with premenopausal breast cancer in Pakistani cohorts.

METHODS

Genomic DNA was isolated from 228 breast cancer patients and 500 non-cancer controls. Six polymorphic variants (rs11568820, rs4516035, rs2228570, rs1544410, rs7975232, rs731236) of the VDR gene were genotyped using PCR-RFLP analysis. All statistical analysis was carried out on IBM-SPSS 23 at p-value <.05. Chi-square test and odds ratios (ORs) along with 95% confidence interval (CIs) were applied to evaluate the relationship between VDR gene polymorphisms and breast cancer.

RESULTS

Results showed that the A/A genotype of EcoRV (OR = 2.125, 95% CI = 1.024 to 4.412) and the A/a genotype of Apa1 (OR = 6.094, 95%CI = 4.111 to 9.033) gene polymorphism had an increased risk of premenopausal breast cancer. No associations of the Bsm1 and Taq1 polymorphisms were observed in premenopausal women. Moreover, the Cdx2 GG (OR = 0.34, 95%CI = 0.192-0.602) genotype had a significant protective effect on breast cancer. However, strong LD was existed between Bsm1/Taq1 (D' = 0.757, CI = 0.67-0.82) and Apa1/Taq1 (D' = 0.695, CI = 0.6-0.77). Haplotype analysis showed no association between premenopausal breast cancer and VDR haplotypes.

CONCLUSION

These analyses indicates that the VDR EcoRV A/A and Apa1 A/a genotypes may be risk factors for breast cancer development among premenopausal women.

Association of vitamin D receptor gene polymorphisms with breast cancer risk

BACKGROUND

Recent literature suggests that vitamin D signaling has a protective effect against breast cancer risk. Thus, the aim of the present study was to find the association of vitamin D receptor (VDR) gene polymorphisms with breast cancer risk.

MATERIALS AND METHODS

Fok1, Bsm1, Apa1, and Taq1 polymorphisms were performed by polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method, and Poly A polymorphism was carried out using PCR-SSCP in 140 breast cancer patients and 155 controls.

RESULTS

Odds ratio was significantly higher in both homozygous variant genotypes (LL) of Poly A polymorphism of VDR (odds ratio [OR] = 5.42, 95% confidence interval [CI] = 1.19-23.31, P = 0.02) and heterozygous variant genotypes (SL) of Poly A polymorphism of VDR (OR = 3.89, 95% CI = 1.10-13.7, P = 0.03). Fok1, Bsm1, Apa1, and Taq1 polymorphisms of VDR gene were not significantly associated with breast cancer risk.

CONCLUSION

Poly A polymorphism at the 3' untranslated region (UTR) of VDR gene was significantly associated with breast cancer risk in West Indian population.

Association Between Vitamin D Binding Protein Gene Polymorphism (rs7041), Vitamin D Receptor, and 25-Hydroxyvitamin D Serum Levels With Prostate Cancer in Kurdish Population in West of Iran

Prostate cancer (PCa) pathology has been linked to vitamin D, vitamin D receptors (VDRs), and vitamin D binding proteins (VDBPs). We sought to investigate the association between VDR rs2228570 and rs1544410 as well as VDBP rs7041 polymorphisms and serum 25-hydroxyvitamin D (25(OH)-vitamin D) levels in PCa patients. Blood samples were collected from 111 PCa patients and 150 age-matched healthy volunteers. The VDR rs2228570 T/C, rs1544410 G/A, and VDBP rs7041 T/G genotypes were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). 25(OH)-vitamin D and PSA (Total and Free) serum levels were measured. The frequencies of VDBP genotypes T/G vs. T/T (56.5% vs. 44.5%, p = 0.01) according to the dominant model T/G + G/G vs. T/T (84.3% vs. 71.5%, p = 0.01) were significantly higher in PCa patients when compared to control group and considerably increased the risk of disease by 2.29, 1.44, and 2.13 folds respectively. Interestingly, the results demonstrated that PCa patients with the dominant model (T/G + G/G vs. T/T) of VDBP had significantly lower serum levels of vitamin D and higher serum levels of total and free PSA in comparison to the controls. Furthermore, when compared to controls, PCa patients with the dominant model T allele (T/G + G/G vs. TT) of VDBP had significantly higher vitamin D, total PSA, and free PSA concentrations. Serum levels of 25(OH)-vitamin D and rs7041 T/G polymorphism of the VDBP gene could be potential risk factors for PCa.

Hormonal and genetic risk factors for breast cancer in a subset of the Karachi population

Objective

Appraisement of vitamin D receptor (VDR) polymorphisms is thought to be crucial to detect and make approaches targeting groups at risk for breast cancer (BC). Moreover, an understanding of genetic susceptibility can allow us to foresee several risk factors. The objective of our research is to evaluate the T to C base shift within TaqI (rs731236) in exon 9 and the A to G transition within Bsm1 (rs1544410) in intron 8 of the VDR gene as risk factors among BC patients.

Methods

The study involved 150 BC patients with a definite histological diagnosis. Controls were age-matched. DNA samples of Taq1 and Bsm1 were amplified according to the programmed protocol using a thermal cycler. The amplified PCR products were digested with Taq1 and Bsm1 restriction endonuclease enzymes. RFLP fragments were observed under UV light using 2% agarose gel and 0.5 ug/mL Ethidium bromide.

Results

The highest number of BC patients (32.7%) were in the 36 to 45 age group. Ethnicity and parity were found to be statistically significant. TaqI polymorphisms showed the highest genotypic frequency for TC (Tt) at 49 (32.7%), and there were 18 patients (12.0%) and controls with high statistical significance (OD 3.6, CI 2–6.4) and a p-value < 0.0001. However, for the Bsm1 genotype, the A (B) allele may be linked with protection from BC in individuals with the AA (BB) genotype.

Conclusion

A positive association was found between VDR genotypes and BC in a collective assay of Taq1 and BsmI. These results need further authentication in large cohort studies prior to applying these SNPs as promising BC markers in the Pakistani populace.

Association of low penetrance vitamin D receptor Tru9I (rs757343) gene polymorphism with risk of premenopausal breast cancer

Objective The aim of this study was to determine whether a novel polymorphism ( Tru9I) in the low penetrance vitamin D receptor (VDR) gene is associated with risk of premenopausal breast cancer (BC). Methods This case-control study included 228 patients with BC and 503 healthy women living in Pakistan who were analyzed for the VDR Tru9I (rs757343) single nucleotide polymorphism. BC cases were histopathologically confirmed, and all healthy controls were age-matched with patients (age range, 20-45 years). DNA was extracted, and the polymerase chain reaction and restriction fragment length polymorphism assays were performed. Results The VDR Tru9I polymorphism was not significantly associated with premenopausal BC. However, the risk of BC was associated with the 'uu' genotype (odds ratio [OR], 1.141; 95% confidence interval [95% CI], 0.206-6.317). Further, mutant Tru9I was significantly associated with Grade IV carcinoma (OR, 5.36; 95% CI, 1.181-24.338). Conclusion The VDR Tru9I 'uu' genotype may increase the risk of premenopausal BC.