We found that CT (miR-196a2, C>T rs11614913) was a risk factor for renal cell carcinoma (CT vs. CC: OR = 1.72, 95%CI = 1.05-2.80, <i>P</i> = 0.03, <i>I</i><sup>2</sup> = 66%), especially in Asian population (CT vs. CC: OR = 1.17, 95%CI = 1.04-1.32, <i>P</i> < 0.01, <i>I</i><sup>2</sup> = 0%). miR-146a G>C rs2910164 was a protective factor of urological cancers (C vs. G: OR = 0.87, 95%CI = 0.81-0.93, <i>P</i> < 0.01, <i>I</i><sup>2</sup> = 0%), especially for bladder cancer. miR-499 A>G rs3746444 was correlated with an increased risk of urological cancers, specifically in Asian population.
Rescue experiment suggested ectopic expression of miR-146a-3p and PTTG1 suppressed migration, invasion and induced cell cycle arrest and senescence of BC cells compared to PTTG1 overexpression, confirming miR-146a-3p inhibited BC progression by targeting PTTG1.
Our study suggested that urinary miR-146a-5p might be useful as a new noninvasive diagnostic marker, therapeutic target, or anticancer agent for bladder cancer, as well as for increasing our understanding of cancer biology.
Our results suggested hsa-mir-196a2 rs11614913 C/T is associated with a significantly decreased risk of bladder cancer and hsa-mir-146ars2910164 GG genotype is associated with clinical stage and metastasis in bladder cancer.
The expression of the miR-200 family, miR-205, miR-192, miR-155, and miR-146a in the urine sediment and supernatant of 51 patients with bladder cancer and in 24 controls was determined by real-time quantitative polymerase chain reaction.
Taken together, our findings show that miR-146ars2910164 plays an important role in the risk and recurrence of bladder cancer, suggesting it may represent a biomarker for risk prevention and therapeutic intervention.