OSE cells were more effective at converting free [3H]-E1 to [3H]-E1S or [3H]-E2S, while EOC cell lines mainly converted [3H]-E1 to [3H]-E2 with minimal formation of [3H]-E1S or [3H]-E2S. IL1α treatment suppressed EST (P < 0.01) and 17BHSD2 (P < 0.001) mRNA levels in OSE and stimulated STS mRNA levels (P < 0.001) in cancer (SKOV3) cells. This evidence concerns the gene STS and cancer.