Differential response of retinoic acid pretreated human synovial sarcoma cell line to anticancer drugs.

The response of tumorigenic human synovial sarcoma (HSS) cell line to 10(-5)M optimum concentration of retinoic acid (RA) included changes in morphology, growth rate, suppression of anchorage-independent growth, induction of high alkaline phosphatase activity and excessive secretion of a 68 kDA glycoprotein of unknown function. HSS cells pretreated with 10(-5)M RA exhibited differential response to 3 potent anticancer drugs, namely cisplatin, vincristine and adriamycin. Sensitivity of the cells to cisplatin was found to be considerably enhanced after exposure to retinoic acid.