MTOR and osteosarcoma: Moreover, RAPA, as the inhibitor of the mammalian target of rapamycin (mTOR) pathway, could not affect miR-126 inhibition of proliferation of U2OS cells, suggesting that the role of miR-126 in osteosarcoma is not dependent on the mTOR pathway.MTT assay showed that both DDP and EGCG could significantly inhibit the proliferation of osteosarcoma U2OS cells.