Previous cancer studies have shown that upregulated glycolysis leads to the nuclear accumulation of PKM2, which can influence histone modification.36 We investigated the distribution of PKM2 in the nucleus and cytoplasm of PCOS and control GC cells and detected similar levels of cytoplasmic PKM2 in these cells; however, clinical PCOS GCs presented significantly increased nuclear PKM2 levels, as evidenced by Western blot and immunostaining analyses (Fig. 2c–e). Here, PKM is linked to cancer.