[Disease-related gene and tumor progression]

Chronic myelogenous leukemia is a stem cell tumor characterized by the t(9; 22)(q34; 11) translocation generating the BCR/ABL chimeric gene. The BCR/ABL fusion gene shows several functions, including inhibition of adhesion to stroma cells and extracellular matrix, activation of mitogenic signalings, inhibition of apoptosis, and degradation of inhibitory proteins, and thereby causes transformation of hematopoietic progenitors. Among its functions, the signal transduction pathways activated by the fusion gene are Ras and MAP kinase pathways, Jak-Stat pathways, PI3 kinase pathways, and Myc pathways. Molecular mechanisms in blastic crisis remains largely unknown. However, loss of functions of tumor suppressor genes such as p53, RB, and p16, activation of oncogene Ras, overexpression of Evi-1 might be involved in disease progression.