(+)-Apogossypol is an antagonist of pan-BCL-2. (+)-Apogossypol binds to Mcl-1(Bcl-2 and Bcl-xL with EC50s of 2.6, 2.8 and 3.69 µM, respectively).

BCL2:2.8 μM (EC50), BCL-XL:3.69 μM (EC50), MCL1:2.6 μM (EC50)

Consistent with NMR binding and fluorescence polarization assay (FPAs) data, (+)-Apogossypol showed an effective binding affinity for Bcl-xL (Kd: 1.7 μM) [1].To investigate the inhibitory effects of (+)-Apogossypol and Gossypol on LNCaP cell survival, the MTT assay is performed. (+)-Apogossypol inhibits the proliferation of LNCaP cells in a time- and dose-dependent manner, in a similar way with Gossypol. The concentration for 50% inhibition (IC50) on LNCaP cells within ~72 h is 9.57 μM, while the IC50 of Gossypol on LNCaP cells is 10.35 μM[2].

The anti-cancer effect of (+)-Apogossypol is evaluated in mice bearing subcutaneous LNCaP cell xenografts. The tumor growth is monitored and measured by a caliper and balance. The survival rate of the mice is notably improved by (+)-Apogossypol. Of note, the tumor sizes are also markedly decreased by (+)-Apogossypol treatment (P<0.01)[2].