[Effects of interferon on the cell cycle of human hepatoma HLF cells analyzed by flow cytometry]

Growth inhibition by interferon (IFN) was investigated in human hepatoma HLF cells by use of flow cytometry to study the cell cycle. INF-alpha or -beta inhibited growth more than IFN-gamma. Use of either IFN-alpha or -beta and IFN-gamma at the same time inhibited growth more than with any one kind of IFN, but use of IFN-alpha and -beta together did not cause much inhibition. IFN inhibited growth by causing cells to accumulate in the S phase instead of moving on to the G2 phase. Accumulation in the S phase was less with IFN-gamma than with -alpha or -beta. It increased with the combination of IFN-alpha or -beta with IFN-gamma, but not with the combination of IFN-alpha and -beta.