Targeting p53-deficient chronic lymphocytic leukemia cells in vitro and in vivo by ROS-mediated mechanism
Metrics: PDF 2475 views | HTML 2312 views | ?
Jinyun Liu1, Gang Chen1, Helene Pelicano1, Jianwei Liao1,2, Jie Huang1, Li Feng1, Michael J. Keating3, Peng Huang1,2
1Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
2Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou 510060, China
3Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
Peng Huang, email: [email protected]
Keywords: CLL, oxidative stress, p53, PEITC
Received: November 03, 2015 Accepted: September 12, 2016 Published: September 19, 2016
Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in Western countries. Loss of p53 function in CLL cells due to chromosome 17p deletion or p53 mutations often leads to a more malignant disease phenotype and is associated with drug resistance and poor clinical outcome. Thus, development of novel therapeutic strategies to effectively target CLL cells with p53 deficiency is clinically important. Here we showed that p53-null CLL cells were highly sensitive to ROS-mediated cell killing due to their intrinsic ROS stress. We further demonstrated that a natural compound phenethyl isothiocyanate (PEITC) was able to effectively kill CLL cells with loss of p53, even under the protection of stromal cells. In p53-defficient CLL cells, PEITC induced a rapid depletion of glutathione and a severe accumulation of ROS, leading to massive leukemia cell death in the stromal microenvironment. The drug-induced cell death was associated with a significant decrease of in MCL-1 survival molecule. We further showed that ROS-mediated cell death was the key mechanism by which PEITC induced cytotoxicity, since such cell death could be prevented by addition of antioxidant NAC. Importantly, in vivo study showed that PEITC was able to induce substantial leukemia cell death in mice. Treatment of CLL mice harboring TCL1-Tg:p53-/- genotype with PEITC significantly prolonged the median survival time of the animals. Our study identifies a vulnerability of p53-null CLL cells with high sensitivity to ROS-generating agents, and suggests that PEITC may potentially be useful for clinical treatment of CLL with 17p deletion and p53 mutations.
All site content, except where otherwise noted, is licensed under a Creative Commons Attribution 4.0 License.