Differential pattern of oncogene and beta-actin expression in leukaemic cells from AML patients

The presence of mRNA hybridizing to five oncogene (fos, mos, myc, sis, abl) and a beta-actin probe(s) was studied with a semiquantitative dot-blot procedure in eight AML patients. Around 10(7) leucocytes, corresponding to 1-10 ml blood, sufficed for the analysis. Each patient, regardless of the FAB group, exhibited a distinct pattern of oncogene or beta-actin expression. Especially strong signals were obtained with the beta-actin probe in two patients and with the fos probe in three patients. The findings underscore the heterogeneity of AML, either present from the first step towards malignancy or arising during the progression of the disease. The pattern of oncogene expression in leukaemic cells studied in routine blood samples may become an additional means for classification and follow-up of AML patients.