STAT3 and osteosarcoma: Given IL-6 is the main upstream activator, but not the downstream target of STAT3, it is not sufficient to to validate the effects of diosmetin on the STAT3 / c-MYC signaling pathway and cell proliferation of osteosarcoma cells by the reversal effects of IL-6 that drives the activation of STAT3/c-Myc pathway.