**2.3 23,24-Dihydrocucurbitacin F (DHCF) (3′)**

 DHCF (**3′**) has been isolated from the roots of *H. amabilis*, an ancient Chinese remedy for bacillary dysentery, gastroenteritis, and cancer. While the toxicity of other cucurbitacins has been explored in several types of cancer, little data exist on the effect of DHCF on human cancers, including prostate cancer (PCa). Human PCa DU145, PC3, and LNCaP cells were treated with graded doses of DHCF in vitro, and the antiproliferative activity of this compound was determined using the MTS assay. DHCF inhibited the proliferation of all three PCa cell lines in a dosedependent manner. The IC50 values of DHCF in DU145, PC3, and LNCaP cells were 15, 7, and 5 μM, respectively [17].
