Antitumor activity of 4-arylcoumarins from endophytic Streptomyces aureofaciens CMUAc130.
In a search for antitumor agents, we carried out a screening of 4-arylcoumarins isolated from endophytic Streptomyces aureofaciens CMUAc130, by examining their possible inhibitory effect on the growth of s.c. transplanted Lewis lung carcinoma (LLC) in BDF-1 mice by intraperitoneal (i.p.) administration. The 4-arylcoumarins showed antitumor activity with T/C values of 80.8 and 50.0% at doses of 1 and 10 mg/kg of 5,7-dimethoxy-4-p-methoxylphenylcoumarin treatment, respectively and 81.5 and 44.9% at doses of 1 and 10 mg/kg of 5,7-dimethoxy-4-phenylcoumarin treatment, respectively, compared to adriamycin, which was used a positive control, with T/C value of 55.9% at 2 mg/kg. Furthermore, we investigated the possible effects of these compounds on expression of the bcl-2 and Bax oncoproteins in A427, a human lung cancer cell lines. The cells were cultured in vitro for 24 h in RPMI 1640 with 1.5% (v/v) ethanol, 100 microg/ml 5,7-dimethoxy-4-p-methoxylphenylcoumarin or 5,7-dimethoxy-4-phenylcoumarin. Viability was determined by an MTT assay. Total protein was extracted from cell lysates and the bcl-2 and Bax oncoproteins were identified. Western blotting showed a decrease in bcl-2 and an increase in Bax in A427 cell cultured with 5,7-dimethoxy-4-p-methoxylphenylcoumarin or 5,7-dimethoxy-4-phenylcoumarin. We conclude that 5,7-dimethoxy-4-phenylcoumarin is a more potent inhibitor of cell proliferation than 5,7-dimethoxy-4-p-methoxylphenylcoumarin and has more marked effects on oncoprotein expression.
Taechowisan
Thongchai
T
Department of Microbiology, Faculty of Science, Silpakorn University, Nakorn Pathom-73000, Thailand. tthongch@su.ac.th
Lu
Chunhua
C
Shen
Yuemao
Y
Lumyong
Saisamorn
S
D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D018827:Carcinoma, Lewis Lung / Q000378:metabolism*; D049109:Cell Proliferation / Q000187:drug effects; D003374:Coumarins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism*; D051379:Mice; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis / Q000378:metabolism; D013304:Streptomyces aureofaciens / Q000737:chemistry*; D051028:bcl-2-Associated X Protein / Q000032:analysis / Q000378:metabolism
D000970:Antineoplastic Agents; D003374:Coumarins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein