Pharmaceutical composition comprising a chemotherapeutic agent and a TGF-beta antisense oligonucleotide, wherein the antisense oligonucleotide reduces the sensitivity and IC50, respectively, of the cytotoxicity of the chemotherapeutic agent. Preferably, the antisense oligonucleotide is a TGF-beta 1, 2, and/or 3 antisense oligonucleotide and the chemotherapeutic agent is preferably gemcitabine, 5-fluorouracil, temozolomide, dacarbacine, docetaxel, cisplatin, oxaliplatin, tamoxifen, or irinotecan.