Increased expression of oncogene c-Ha-ras during granulocytic differentiation of HL60 cells.

The expression of several oncogenes is known to be up-regulated during monocytic differentiation of human leukemic cells HL60, but an alternate pathway of differentiation of these cells, towards the granulocyte, has not been associated with elevated levels of oncogene expression. We report that the rates of transcription and the steady state mRNA levels of oncogene c-Ha-ras increase during granulocytic differentiation of HL60 cells, and correlate with the acquisition of the phenotypic markers of differentiation. This increase may be related to the function of the ras product as one of the components of the G-protein group, which were implicated recently in the regulation of the physiological activities of the granulocyte.