Interestingly, enforced expression of WASP in BCR-ABL1-positive K562 cells increases the susceptibility to apoptosis induced by TRAIL or chemotherapeutic drugs and negatively modulates BCR-ABL1-induced tumorigenesis in vitro and in vivo.
BCR-ABL governs carcinogenesis through well-organized web of antiapoptotic proteins and over-expressed oncomirs which target death receptors and pro-apoptotic genes.
Increasing sophisticated information suggests that cancer cells express constitutively active oncogenic kinases such as breakpoint cluster region- c-abl oncogene 1, non-receptor tyrosine kinase (BCR-ABL1) that promote carcinogenesis independent of extrinsic growth factors.
Since resistance to apoptosis is an essential step for the tumorigenesis process, we next examined the effect of the MPA-mediated necrotic signal on different tumor cells demonstrating various mechanisms of resistance to apoptosis (Bcl2-, HSP70-, Lyn-, BCR-ABL-overexpressing cells).
These findings implicate activation of Ras function as an important component in BCR-ABL-mediated transformation and demonstrate that GRB-2 not only functions in normal development and mitogenesis but also plays a role in oncogenesis.