In summary, miR-194-5p can directly inhibit HIF-1 and regulate the expression of a series of downstream proteins including BAX, cleaved caspase-9, cleaved caspase-3, cleaved PARP, and P-gp, thus enhancing the therapeutic effect of DOX on NSCLC cells and promoting NSCLC cell apoptosis. This evidence concerns the gene CASP9 and non-small cell lung carcinoma.