Rebeccamycin is an indolocarbazole antibiotic produced by S. aerocolonigenes ATCC39243 that weakly inhibits DNA topoisomerase I. It is cytotoxic to human lung adenocarcinoma, colon carcinoma, and nasopharyngeal carcinoma cell lines (IC50s range from 0.4-98 μM), producing single-strand breaks in the DNA of these tumor cells.
