MIR4463: MIR4463 is a microRNA that has been studied in relation to its regulation of CYP19A1 and ESR1 expression in KGN cells [PMC7482943]. Recent research has shown that MIR4463 expression is significantly upregulated in the serum of patients with polycystic ovary syndrome (PCOS), although its specific biological functions related to PCOS are still unknown [PMC7482943]. However, the data strongly suggest that MIR4463 plays a crucial role in regulating 17β-estradiol synthesis by targeting CYP19A1 and ESR1 in KGN cells [PMC7482943]. To validate these findings, a comparison of MIR4463 expression levels in the serum of poor responders and normal responders undergoing in vitro fertilization (IVF) is needed [PMC7482943]. Interestingly, it was found that MIR4463 showed significantly increased expression in poor responders, indicating its potential role in regulating 17β-estradiol synthesis and suggesting it as a potential predictor of poor ovarian response (POR) [PMC7482943]. Immunoblotting analyses further supported these findings by demonstrating that the miR-4463 mimic decreased CYP19A1 protein expression levels by approximately 40%, while the MIR4463 inhibitor treatment did not affect CYP19A1 expression [PMC7482943]. Overall, these results suggest that upregulation of MIR4463 may contribute to reduced 17β-estradiol production and POR, highlighting its potential as a therapeutic target or predictor for POR patients undergoing IVF treatment [PMC7482943].