Topoisomerase I inhibitor SN-38 effectively attenuates growth of human non-small cell lung cancer cell lines in vitro and in vivo.

The effect of SN-38 was evaluated on multiple lung cancer cell lines. It inhibits anchorage-dependent and -independent growth as monitored by MTT and soft agar colony assay, respectively. SN-38 collapsed the mitochondrial membrane potential (MMP), arrested cells in S- and G2-phases of the cell cycle, and induced apoptosis via activation of caspase 3 and PARP. A single injection of 2 mg/kg body weight of SN-38 caused a significant reduction of lung cancer xenografts. These findings indicate that SN-38 induces apoptosis in the lung cancer cells effectively. Thus, SN-38 can potentially be an effective therapeutic agent against lung cancer.