Dual inhibition of PI3K/mTOR signaling in chemoresistant AML primary cells

Publication date: Available online 19 March 2018 Source:Advances in Biological Regulation Author(s): Jessika Bertacchini, Chiara Frasson, Francesca Chiarini, Daniele D'Avella, Benedetta Accordi, Laura Anselmi, Patrizia Barozzi, Fabio Foghieri, Mario Luppi, Alberto M. Martelli, Giuseppe Basso, Saki Najmaldin, Abbas Khosravi, Fakher Rahim, Sandra Marmiroli A main cause of treatment failure for AML patients is resistance to chemotherapy. Survival of AML cells may depend on mechanisms that elude conventional drugs action and/or on the presence of leukemia initiating cells at diagnosis, and their persistence after therapy. MDR1 gene is an ATP-dependent drug efflux pump known to be a risk factor for the emergence of resistance, when combined to unstable cytogenetic profile of AML patients. In the present study, we analyzed the sensitivity to conventional chemotherapeutic drugs of 26 samples of primary blasts collected from AML patients at diagnosis. Detection of cell viability and apoptosis allowed to identify two group of samples, one resistant and one sensitive to in vitro treatment. The cells were then analyzed for the presence and the activity of P-glycoprotein. A comparative analysis showed that resistant samples exhibited a high level of MDR1 mRNA as well as of P-glycoprotein content and activity. Moreover, they also displayed high PI3K signaling. Therefore, we checked whether the association with signaling inhibitors might resensitize resistant samples to ch...
Source: Advances in Biological Regulation - Category: Biology Source Type: research