5-Fluorouracil incorporation into human breast carcinoma RNA correlates with cytotoxicity.
We demonstrate a highly significant relationship (p less than 0.0001) between the incorporation of 5-flourouracil in total cellular RNA and loss of clonogenic survival of the human MCF-7 breast carcinoma cell line. The extent of 5-fluorouracil incorporation in RNA is concentration- and time-dependent. Identical results are obtained in experiments employing thymidine to bypass the block of thymidylate synthetase and reverse inhibition of DNA synthesis. These studies suggest that the incorporation of 5-fluorouracil in RNA is the major mechanism of cytotoxic action in this human cell line.
D001943:Breast Neoplasms / Q000503:physiopathology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002999:Clone Cells; D004305:Dose-Response Relationship, Drug; D005260:Female; D005472:Fluorouracil / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D012334:RNA, Neoplasm / Q000096:biosynthesis*; D014316:Tritium
D012334:RNA, Neoplasm; D014316:Tritium; D005472:Fluorouracil