Synthesis of some steroidal mitocans of nanomolar cytotoxicity acting by apoptosis

Abstract

Several steroids (abiraterone, prednisone, testosterone, cholesterol) and the BCL-2 inhibitor bexarotene were used as starting materials to synthesize iperazinyl-spacered rhodamine B conjugates. The conjugates were screened for their cytotoxicity in SRB assays against several human tumor cell lines and found to be active in a low μM to nM range. The conjugate derived from testosterone held an EC₅₀ = 59 nM against MCF-7 tumor cells and acted mainly by necrosis. The prednisone conjugate, however, was less cytotoxic but acted mainly by apoptosis and held a moderate selectivity against MCF-7 tumor cells.

Keywords: Apoptosis; Cytotoxicity; Prednisone; Rhodamine B; Steroids; Synthesis.