Further stratified analyses showed that rs2910164 is associated with the tumor stage in a recessive model and with metastasis in a dominant model (P = 0.012, OR = 0.20, 95 % CI = 0.05-0.72 and P = 0.04, OR = 2.63, 95 % CI = 1.03-6.67, respectively).
We found that the miR-146a polymorphism rs2910164 might significantly increase the susceptibility of digestive tumors, in particular for esophageal cancer and colorectal cancers.
Comparison between groups divided by clinicopathologic features showed that the polymorphism of miR-146a was associated with the degree of tumor differentiation (p = 0.014), and the G allele of rs2910164 trended to a mature differentiation (OR = 0.553; 95% CI = 0.315-0.971; p = 0.038).
We analyzed HPV16 status in tumor specimens and genotyped four SNPs in pre-miRNAs (hsa-mir-146a rs2910164 G>C, hsa-mir-149 rs2292832 G>T, hsa-mir-196a2 rs11614913 C>T, and hsa-mir-499 rs3746444 A>G) in 309 SCCOP patients.
Moreover, a multivariate analysis showed that the CC genotype of miR-146a rs2910164 was associated with worse relapse-free and disease-specific survival compared to the CG or GG genotype in a recessive model of the C allele, adjusted for patient and tumor characteristics (hazard ratio=2.120 and 2.349, p=0.005 and 0.007, respectively).
Results of stratified analyses revealed that rs2910164 is associated with tumor differentiation and lymph node status (P = 0.043, OR = 2.08, and a borderline P = 0.057, OR = 0.41, respectively).