Association study of genetic variants in estrogen metabolic pathway genes and colorectal cancer risk and survival.

Although studies have investigated the association of genetic variants and the abnormal expression of estrogen-related genes with colorectal cancer risk, the evidence remains inconsistent. We clarified the relationship of genetic variants in estrogen metabolic pathway genes with colorectal cancer risk and survival. A case-control study was performed to assess the association of single-nucleotide polymorphisms (SNPs) in ten candidate genes with colorectal cancer risk in a Chinese population. A logistic regression model and Cox regression model were used to calculate SNP effects on colorectal cancer susceptibility and survival, respectively. Expression quantitative trait loci (eQTL) analysis was conducted using the Genotype-Tissue Expression (GTEx) project dataset. The sequence kernel association test (SKAT) was used to perform gene-set analysis. Colorectal cancer risk and rs3760806 in SULT2B1 were significantly associated in both genders [male: OR = 1.38 (1.15-1.66); female: OR = 1.38 (1.13-1.68)]. Two SNPs in SULT1E1 were related to progression-free survival (PFS) [rs1238574: HR = 1.24 (1.02-1.50), P = 2.79 × 10-2 ; rs3822172: HR = 1.30 (1.07-1.57), P = 8.44 × 10-3 ] and overall survival (OS) [rs1238574: HR = 1.51 (1.16-1.97), P = 2.30 × 10-3 ; rs3822172: HR = 1.53 (1.67-2.00), P = 2.03 × 10-3 ]. Moreover, rs3760806 was an eQTL for SULT2B1 in colon samples (transverse: P = 3.6 × 10-3 ; sigmoid: P = 1.0 × 10-3 ). SULT2B1 expression was significantly higher in colorectal tumor tissues than in normal tissues in the Cancer Genome Atlas (TCGA) database (P < 1.0 × 10-4 ). Our results indicated that SNPs in estrogen metabolic pathway genes confer colorectal cancer susceptibility and survival.