Significantly, the tumors in the doxorubicin-injected mice bearing HSPB1-overexpressing cells were significantly larger and heavier compared to those in doxorubicin-injected mice implanted with control cells (Fig. 8A–C), suggesting that overexpression of HSPB1 attenuated the anti-tumor effect of doxorubicin. The gene discussed is HSPB1; the disease is neoplasm.