Involvement of the NF‐κB pathway in the transforming properties of the TEL–Jak2 leukemogenic fusion protein

Abstract
Constitutively active tyrosine kinases are frequently expressed in various types of human leukemias as the result of chromosomal translocations. The TEL–Jak2 fusion oncoprotein possesses transforming properties in both animal and cellular models, that are tightly dependent on Stat5 activation. In the IL-3-independent TEL–Jak2-transformed Ba/F3 cells, activation of the PI-3K/Akt pathway appears essential to cell proliferation. Here we report a sustained activation of NF-κB factors in Ba/F3 cells, which inhibition dramatically impairs cell viability, indicating that NF-κB signaling exerts a major role in the anti-apoptotic activities of TEL–Jak2 oncoprotein.