Study on the anti-colon cancer activity of boanmycin
Zhang Hong-yin 1,Xie Zhong 2,Li Zong-kai 2andLi Dian-dong 2 (1 Peking University Hosptal,Beijing 100871; 2 Institute of Medicinal Biotechnology, Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100050)
In vitro and in vivo anti-colon cancer activities of boanmycin (BAM) as well as its action concerning with the macromolecular synthesis of cancer cells, the effect and expressiong on the cancer genes, and anti-cance genes, and the infuence on the DNA lesion and repair were investigated. Boanmycin possessed a potent antitumor activitiy and showed obvious dose-response relationship. In vitro clonogenic assay showed that the IC 50 against HT-29 cells of BAM was 3.8×10 -8mol/L; NAG enzymatic assay revealed that the cytotoxicity of BAM was stronger of an order magnitude, when compared with other bleomycin antitiotic family, e.g. pepleo-mycin, bleomycin (BLM), BLM-A 5 and BLM-A 6 against HT-29 cells. Tritium labeled detemination of BAM against human colon cancer cells showed that it had potent inhibitory activities to the protein synthesis cancer cells and was the strongest when compared to DNA and RNA inhibitions. By dot blotting assay, BAM at concentration of 10 -5 mol/L, the gene expression of c-myc and p53 derived from colon HT-29 cells were significantly inhibited, which the expression of N-ras gene was enhanced. By neutral gel electrophoresis method, the damaged DNA of HT-29 when pre-incubated with BAM for 1 hour, was able to repaired itself. It was concluded that BAM was a potent and wide spectrum anti-tumor antibiotic. It had strong inhibit activity against the tumor of digestive system.