A genetic polymorphism (rs17251221) in the calcium-sensing receptor is associated with ovarian cancer susceptibility.

Calcium-sensing receptor (CaSR) is a G-protein‑ coupled receptor that senses blood calcium. In vivo, CaSR is required for normal epidermal differentiation by mediating calcium signaling. CaSR was confirmed to be a tumor suppressor in colon and breast cancer. The single-nucleotide polymorphism (SNP) rs17251221, located on the intron, is a genetic variation of the CaSR gene. We analyzed rs17251221 in ovarian cancer using an allelic discrimination assay. Cycling probes were used for genotyping 290 ovarian cancer patients and 312 age-matched cancer-free females. rs17251221 and clinicopathological characteristics of ovarian cancer were analyzed statistically. The AG and GG genotypes were confirmed to appear in fewer cancer cases than in controls and the genotype distribution between cases and controls was statistically significant. The AG+GG genotype was correlated with low ovarian cancer risk, while rs17251221 was not associated with clinicopathological variables including age at diagnosis, tumor size, histologic type, pathological subtype, lymph node metastasis, CA-125 expression, clinical stage, or degree of differentiation. The rs17251221 polymorphism genotype was not correlated with survival in ovarian cancer. These results suggest that the G allele of the CaSR rs17251221 polymorphism is protective against ovarian cancer and the homozygous GG genotype may be a protective genotype as well. The rs17251221 may play an important role in the development of ovarian cancer and could be used as a biomarker for predicting ovarian cancer.