Microenvironment-induced PIM kinases promote CXCR4-triggered mTOR pathway required for chronic lymphocytic leukaemia cell migration.

Microenvironment-induced PIM kinases promote CXCR4-triggered mTOR pathway required for chronic lymphocytic leukaemia cell migration. J Cell Mol Med. 2018 Apr 17;: Authors: Białopiotrowicz E, Górniak P, Noyszewska-Kania M, Puła B, Makuch-Łasica H, Nowak G, Bluszcz A, Szydłowski M, Jabłonska E, Piechna K, Sewastianik T, Polak A, Lech-Marańda E, Budziszewska BK, Wasylecka-Juszczyńska M, Borg K, Warzocha K, Czardybon W, Gałęzowski M, Windak R, Brzózka K, Juszczyński P Abstract Lymph node microenvironment provides chronic lymphocytic leukaemia (CLL) cells with signals promoting their survival and granting resistance to chemotherapeutics. CLL cells overexpress PIM kinases, which regulate apoptosis, cell cycle and migration. We demonstrate that BCR crosslinking, CD40 stimulation, and coculture with stromal cells increases PIMs expression in CLL cells, indicating microenvironment-dependent PIMs regulation. PIM1 and PIM2 expression at diagnosis was higher in patients with advanced disease (Binet C vs. Binet A/B) and in those, who progressed after first-line treatment. In primary CLL cells, inhibition of PIM kinases with a pan-PIM inhibitor, SEL24-B489, decreased PIM-specific substrate phosphorylation and induced dose-dependent apoptosis in leukaemic, but not in normal B cells. Cytotoxicity of SEL24-B489 was similar in TP53-mutant and TP53 wild-type cells. Finally, inhibition of PIM kinases decreased CXCR4-mediated cell chemotaxis ...
Source: J Cell Mol Med - Category: Molecular Biology Authors: Tags: J Cell Mol Med Source Type: research