Expression of stem cell factor mRNA in primary leukemia cells

OBJECTIVE: To observe the expression of stem cell factor (SCF) mRNA in primary human leukemia cells and investigate its significance in deciding the prognosis of leukemia patients. METHODS: Primary leukemia cells were isolated form the bone marrow of 49 patients with leukemia, and the expression of SCF mRNA determined by nested reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: Among the 19 patients with acute lymphatic leukemia (ALL), 5 were positive and 14 negative for SCF mRNA. In cases of acute myeloid leukemia (AML, n=30), 24 of M1 to M4 subtypes were found positive for SCF mRNA but 4 of M5 subtype and 2 of M6 subtype were negative. There was a significant difference between ALL and AML groups (P<0.05). Eight (27.6%) cases were refractory leukemia in the total of 29 patients who were positive for SCF, while 12 (60.0%) were refractory among the 20 patients negative for SCF (P<0.05). CONCLUSIONS: The expression rate of SCF was significantly higher in AML than in ALL cases, and the negative expression of SCF mRNA might be indicative of unfavorable prognosis, but the exact mechanism needs futher investigation.