Polymorphisms in the 3' untranslated region of STAT3 mRNA can derange STAT3 gene expression via modifying the microRNA-binding site. This study aimed to examine the impact of STAT3 rs1053005 variation and miR-452-3p expression on osteoarthritis (OA) susceptibility and severity and the efficacy of intra-articular high-molecular-weight hyaluronic acid (HMW-HA) injection as a therapy option for knee OA. Two hundred and fifty-eight OA patients and 200 healthy controls were enrolled in the study. STAT3 genotyping and STAT3 and miR-452-3p expression were carried out using allelic-discrimination PCR and quantitative real-time PCR. Functional assessment and pain evaluation were performed for all patients. Eighty-three patients received HMW-HA injections, and multiple follow-up visits were performed. STAT3 mRNA was upregulated, and expression was positively associated with plasmin, TNF-α, MMP-3, and STAT3 serum levels, whereas miR-452-3p was downregulated and negatively associated with the previously mentioned parameters in OA patients. Osteoarthritis patients had a lower prevalence of the minor allele of the rs1053005 variant (p < 0.001). Plasmin, TNF, MMP-3, and STAT3 mRNA and protein levels were significantly decreased, and miR-452-3p expression was significantly increased in the GG genotype compared to AG and AA genotypes. HMW-HA injection improved OA patients' clinical scores with concomitant decreased STAT3 levels and enhanced expression of miR-452-3p. More efficient improvement was observed in rs1053005 AG + GG genotype carriers vs. AA genotype carriers. The G allele of STAT3 rs1053005 (A/G) polymorphism was associated with decreased OA susceptibility and severity and enhanced clinical response to HMW-HA injection, possibly via enhancing miR-452-3p binding and a subsequent decrease in STAT3 expression.
Keywords: HMW-HA injections; STAT3; miR-452-3p; osteoarthritis; rs1053005.