Cancer: Breast
Action: Estrogen modulator
The seed of Psoralea corylifolia L. (PCL), a well-known traditional Chinese medicine, has been applied as a tonic or an aphrodisiac agent and commonly used as a remedy for bone fracture, osteomalacia and osteoporosis in China (Lim et al., 2009).
Estrogen Modulator
The estrogen receptor subtype-selective activities of the extracts and compounds derived from PCL were analyzed using the HeLa cell assay. The different fractions, including petroleum ether, CH(2)Cl(2) and EtOAc fractions of the EtOH extract of PCL, showed significant activity in activating either ERalpha or ERbeta, whereas the n-BuOH fraction showed no estrogenic activity. Further chromatographic purification of the active fractions yielded seven compounds including the two coumarins isopsoralen and psoralen, the four flavonoids isobavachalcone, bavachin, corylifol A and neobavaisoflavone, and the meroterpene phenol, bakuchiol. In reporter gene assay, the two coumarins (10(-8)-10(-5)M) acted as ERalpha-selective agonists while the other compounds (10(-9)-10(-6)M) activated both ERalpha and ERbeta.
The estrogenic activities of all compounds could be completely suppressed by the pure estrogen antagonist, ICI 182,780, suggesting that the compounds exert their activities through ER. Only psoralen and isopsoralen as ERalpha agonists promoted MCF-7 cell proliferation significantly. Although all the compounds have estrogenic activity, they may exert different biological effects. These data suggest that both ER subtype-selective and non-selective activities in compounds derived from PCL indicated that PCL could be a new source for selective estrogen-receptor modulators (Xin et al., 2010).
Breast Cancer
The in vitro anti-tumor activity of bakuchiol was examined, compared with tamoxifen. The result of biological activities showed that bakuchiol could inhibit human breast cancer and the IC50 values were 2.89 x 10(-5) mol L(-1) and 8.29 x 10(-3) mol L(-1) against the cells line T-47D and MDA-MB-231 respectively (Chen et al., 2010).
In vitro inhibitory effects of various concentrations of psoralen (25, 12. 5, 6. 25 and 3. 125 µg/mL respectively) on MCF-7 cells with estrogen-receptor (ER) positive and on MDA-MB-231 cells with ER negative were carried out. Psoralen had no inhibitory effect on the growth of MDA-MB-231 cells, but cell apoptosis was increased at early stage. There were 1,053 genes with differential expression in MCF-7 cells assessed by cDNA chips. Of the expression of 1,053 genes, the expression of 657 genes was down-regulated and that of 456 gene was up-regulated.
Psoralen has certain inhibitory effect on the proliferation of ER-positive MCF-7 cells, and its inhibitory mechanism on the growth of breast cancer is probably related to the arrest of the cell at G2 phase by the drug (Tan et al., 2009).
References