J. Nat. Prod.: the traditional Mexican drug Huansheng accidentally contains new triterpenoids against nasopharyngeal carcinoma

According to the statistics of the World Health Organization, cancer is one of the main causes of global death, which has led to 8.2 million deaths in 2012 The disease is characterized by abnormal cell growth, and there are many drugs available for treatment However, most of the existing therapies have the disadvantages of high cost, excessive side effects, poor efficacy for metastatic tumors, and may also lead to the occurrence of multidrug resistance in abnormal cells The current research focuses on the search and development of new anticancer drugs with minimal toxic effects One way to find new drugs is to separate compounds from plants Because many natural metabolites have been proved to have good anticancer activity, they can be developed into effective drugs for cancer chemotherapy In the selection of plant standards for the discovery of bioactive metabolites, a common source is the use of some known traditional medicinal plants The structural formula of compounds 1, 2 and 3 (source: J NAT Prod.) in the traditional medical literature of Yucatan Peninsula, Mexico, recorded some plant drugs for treating similar cancer symptoms Twenty one of them were selected and their cytotoxic activities in vitro were studied to find new drug precursors with potential anticancer activities Among them, methanol extract of phoradendronvernicosum greenm (Santalaceae) was found to have activity on NPC cells Plants of the genus Phoradendron in Mexico have a wide geographical distribution, and the plants belonging to this taxonomic population are called mistletoe species Phoradendron can be used in traditional medicine around the world to treat a variety of diseases, including some cancer like symptoms In the past, chemical analysis of some Phoradendron species has reported the separation of triterpenoids and flavonoids However, little is known about the chemical composition of other photoredendron species This is the first phytochemical report on P vernicosum The NMR data of compounds 1, 2 and 3 (source: J NAT Prod.) were obtained from Sergio R peraza-s á nchez in Mexico A team led by Sergio R peraza-s á nchez used methanol to extract the chemicals in P vernicosum, and then separated the methanol extracts by chromatography Finally, 11 separated products were obtained Three new triterpenoids were found: 3 α, 24-dihydroxyup-20 (29) - en-28-oic acid (1), 3 α, 23-dihydroxy-30-oxolup-20 (29) - en-28-oic acid (2), 3 α, 23-o-isoprotylidenyl-3 α, 23-dihydroxyup-20 (29) - en-28-oicacid (3) Eight known compounds, lupenone (4), betulinic acid (5), 3-epi-betulinic acid (6), 3 α, 23-dihydroxylup-20 (29) - en-28-oicacid (7), betuline (8), betulinic acid (9), oleanolic acid (10), betulin (11), were also obtained The purified compounds were characterized by IR, 1H-NMR and 13C-NMR, and their molecular structures were determined In order to evaluate the antitumor activity of compound 1-11 in vitro, 7 kinds of human cancer cells (MCF-7, MDA-MB-231, HeLa, SiHa, DU-145, KB and Hep2) and two kinds of normal somatic cells (Vero and HEK-293) were used The cytotoxic activity (cc50) of compounds 1 - 11 ranged from 10.2 to 197.4 μ m, while its antiproliferative activity (IC50) was 12.5 to 204.5 μ M Although according to the classification of the National Cancer Institute, the test results of compounds 1-11 are classified as inactive (the activity standard is CC 50 or IC 50 value ≤ 10 μ m), the cell selectivity index (SI) of compound 3 for nasopharyngeal carcinoma (KB) seems to be worth mentioning If it is modified further, it is possible to obtain anticancer active substance with activity standard Paper link: http://pubs.acs.org/doi/abs/10.1021/acs.jnatprod.7b00177