The effect of brassinolide, a plant steroid hormone, on drug resistant small-cell lung carcinoma cells.

Small-cell lung carcinoma (SCLC) has a dismal prognosis in part because of multidrug resistance (MDR). Epibrassinolide (EB) is a steroid hormone in plants, with many physiological effects. It acts via a membrane receptor and GSK3 pathway, resulting in stabilization of a transcription factor. The parallels to the Wnt signaling pathway, which is activated in SCLC and results in increased β-catenin, prompted investigations of the effects of EB on drug-resistant (VPA17) and drug-sensitive (H69) SCLC cells. EB was cytotoxic to both cell lines (IC