Here, we show that (1) down-regulation of Onc-p53 increases the expression of a pro-apoptotic BH3-only BCL-2 family protein, BIM, and sensitizes to venetoclax in SCLC-P cells; (2) targeting Onc-p53 by the HSP90 inhibitor, ganetespib [22], increases BIM expression and sensitizes to venetoclax in SCLC-P and SCLC-A cells. Here, TP53 is linked to small cell lung carcinoma.