Arsenic trioxide disrupts glioma stem cells via promoting PML degradation to inhibit tumor growth.

Abstract

Glioblastoma multiforme (GBM) is the most lethal brain tumor. Tumor relapse in GBM is inevitable despite maximal therapeutic interventions. Glioma stem cells (GSCs) have been found to be critical players in therapeutic resistance and tumor recurrence. Therapeutic drugs targeting GSCs may significantly improve GBM treatment. In this study, we demonstrated that arsenic trioxide (As2O3) effectively disrupted GSCs and inhibited tumor growth in the GSC-derived orthotopic xenografts by targeting the promyelocytic leukaemia (PML). As2O3 treatment induced rapid degradation of PML protein along with severe apoptosis in GSCs. Disruption of the endogenous PML recapitulated the inhibitory effects of As2O3 treatment on GSCs both in vitro and in orthotopic tumors. Importantly, As2O3 treatment dramatically reduced GSC population in the intracranial GBM xenografts and increased the survival of mice bearing the tumors. In addition, As2O3 treatment preferentially inhibited cell growth of GSCs but not matched non-stem tumor cells (NSTCs). Furthermore, As2O3 treatment or PML disruption potently diminished c-Myc protein levels through increased poly-ubiquitination and proteasome degradation of c-Myc. Our study indicated a potential implication of As2O3 in GBM treatment and highlighted the important role of PML/c-Myc axis in the maintenance of GSCs.

• Authors: Wenchao Zhou, Lin Cheng, Yu Shi, Susan Q Ke, Zhi Huang, Xiaoguang Fang, Cheng-wei Chu, Qi Xie, Xiu-wu Bian, Jeremy N Rich, Shideng Bao
• Journal: Oncotarget (Oncotarget) Vol. 6 Issue 35 Pg. 37300-15 (Nov 10 2015) ISSN: 1949-2553 [Electronic] United States
• PMID: 26510911 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• Arsenicals
• MYC protein, human
• Nuclear Proteins
• Oxides
• Promyelocytic Leukemia Protein
• Proto-Oncogene Proteins c-myc
• Transcription Factors
• Tumor Suppressor Proteins
• PML protein, human
• Arsenic Trioxide

Topics

• Animals
• Antineoplastic Agents (pharmacology)
• Arsenic Trioxide
• Arsenicals (pharmacology)
• Brain Neoplasms (drug therapy, genetics, metabolism, pathology)
• Cell Proliferation (drug effects)
• Female
• Glioblastoma (drug therapy, genetics, metabolism, pathology)
• Humans
• Mice, Inbred C57BL
• Mice, Nude
• Neoplastic Stem Cells (drug effects, metabolism, pathology, transplantation)
• Nuclear Proteins (genetics, metabolism)
• Oxides (pharmacology)
• Promyelocytic Leukemia Protein
• Proteolysis
• Proto-Oncogene Proteins c-myc (genetics, metabolism)
• RNA Interference
• Signal Transduction (drug effects)
• Spheroids, Cellular
• Time Factors
• Transcription Factors (genetics, metabolism)
• Transfection
• Tumor Burden (drug effects)
• Tumor Cells, Cultured
• Tumor Suppressor Proteins (genetics, metabolism)
• Xenograft Model Antitumor Assays