Cytotoxic Properties of Root Extract and Fruit Juice of Trichosanthes cucumerina

The root extract of Trichosanthes cucumerina L. and bryonolic acid (1), its main constituent, as well as the fruit juice and cucurbitacin B (3), its main constituent, were tested for cytotoxicity against four human breast cancer cell lines (SKBR3, MCF7, T47D, and MDA-MB435), two lung cancer cell lines (A549 and SK-LU1), and one colon cancer cell line (Caco-2). The root extract had higher IC50 values than bryonolic acid (I) against three breast cancer cell lines (MCF7 = 267/121, T47D = 316/124, MDA-MB435 = 140/90 mu L/mL) and one lung cancer cell line (A549 = 106/100 mu L/mL). The fruit juice also had higher IC50 values than cucurbitacin B (3) against the four breast cancer cell lines (131/73, 375135, 249/60, and 156/26 mu L/mL, respectively) and one lung cancer cell line (141/41 mu L/mL) as shown above, as well as against the colon cancer cell line (101/1.5 mu L/mL). However, the root extract inhibited SK-LU1 more strongly than did the fruit juice, Cucurbitacin B (3), and bryonolic acid (1) (149/169/180/>500 mu L/mL, respectively). The root extract inhibited the two lung and three breast cancer cell lines (SKBR3, MDA-MB435, and MCF7) more strongly than the fruit juice. Bryonolic acid (1) inhibited MDA-MB435 somewhat better than the other tested human cancer cell fines. The fruit juice inhibited the colon cancer cell line (Caco-2) more strongly than the root extract. Cucurbitacin (3) inhibited human cancer cell lines, especially Caco-2, Much more strongly than bryonolic acid (1). In addition to bryonolic acid (1), bryononic acid (2), cucurbitacin B (3), and dihydrocucurbitacin B (4) also were isolated from the root extract.