IGF1 and polycystic ovary syndrome: Furthermore, Mao et al. [38] revealed that the overexpression of the klotho gene is crucial in ovarian GC apoptosis in PCOS and that loss of miR-126-5p and miR-29a-5p expression is an etiological factor; thus, the miR-126-5p, miR-29a-5p/klotho/insulin-IGF-1, Wnt, and Akt signaling pathways may have a role in GC apoptosis and subsequently in PCOS development [38].