Expression Study On The Colony-Stimulating Factor-Associated JAK/STAT Signaling Proteins

Objective To investigate the relationship between the activated JAK/STAT proteins and the proliferation of myeloid leukemic cell.Methods In human myeloid TF-1 cell line, immunoprecipitation and Western Blot analysis was used to determine if there were tyrosine phosphorylated JAK2 and STAT3 induced by GM-CSF; Simultaneously the apoptotic and proliferative status was observed on the due time.Results In TF-1 cell line, the activation of JAK2 but not STAT3 was detected induced by GM-CSF; Moreover this cell line was observed to proliferate in a dose- and time-dependent manner induced by GM-CSF; In addition,GM-CSF could protect TF-1 cells from apoptosis demonstrated by morphological alteration and DNA fragmentization.Conclusion GM-CSF was essential for the protection of cells from apoptosis and promotion of proliferation of TF-1 cells; Moreover, GM-CSF-induced biological effect was associated with the activation of JAK2; In addition, activated JAK/STAT signal pathway may be involved in the apoptosis and proliferation, which further confirmed the autocrine or paracrine mechanism of leukemogenesis.