INSR and polycystic ovary syndrome: While multiple mechanisms have been proposed for the insulin resistance seen in patients with PCOS, such as decreases in kinase activity, phosphorylation of insulin-receptor substrate, PI3K activity, and glucose transporter translocation [49, 50], impairment of downstream metabolic insulin signaling [51], and increased androgen production in the ovary [52, 53], this process is still poorly understood.