1
|
Wang L, Howell ME, McPeak B, Riggs K, Kohne C, Yohanon JU, Foxler DE, Sharp TV, Moorman JP, Yao ZQ, Ning S. LIMD1 is induced by and required for LMP1 signaling, and protects EBV-transformed cells from DNA damage-induced cell death. Oncotarget 2018; 9:6282-6297. [PMID: 29464072 PMCID: PMC5814212 DOI: 10.18632/oncotarget.23676] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 12/11/2017] [Indexed: 11/25/2022] Open
Abstract
LIMD1 (LIM domain-containing protein 1) is considered as a tumor suppressor, being deregulated in many cancers to include hematological malignancies; however, very little is known about the underlying mechanisms of its deregulation and its roles in carcinogenesis. Epstein-Barr Virus (EBV) is associated with a panel of malignancies of lymphocytic and epithelial origin. Using high throughput expression profiling, we have previously identified LIMD1 as a common marker associated with the oncogenic transcription factor IRF4 in EBV-related lymphomas and other hematological malignancies. In this study, we have identified potential conserved IRF4- and NFκB-binding motifs in the LIMD1 gene promoter, and both are demonstrated functional by promoter-reporter assays. We further show that LIMD1 is partially upregulated by EBV latent membrane protein 1 (LMP1) via IRF4 and NFκB in EBV latency. As to its role in the setting of EBV latent infection, we show that LIMD1 interacts with TRAF6, a crucial mediator of LMP1 signal transduction. Importantly, LIMD1 depletion impairs LMP1 signaling and functions, potentiates ionomycin-induced DNA damage and apoptosis, and inhibits p62-mediated selective autophagy. Taken together, these results show that LIMD1 is upregulated in EBV latency and plays an oncogenic role rather than that of a tumor suppressor. Our findings have identified LIMD1 as a novel player in EBV latency and oncogenesis, and open a novel research avenue, in which LIMD1 and p62 play crucial roles in linking DNA damage response (DDR), apoptosis, and autophagy and their potential interplay during viral oncogenesis.
Collapse
Affiliation(s)
- Ling Wang
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
| | - Mary E.A. Howell
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
| | - Brooke McPeak
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
| | - Katrina Riggs
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
| | - Carissa Kohne
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
| | - Jether Uel Yohanon
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
| | - Daniel E. Foxler
- Centre for Molecular Oncology, Barts Cancer Institute, University of London, London EC1M 6BQ, UK
| | - Tyson V. Sharp
- Centre for Molecular Oncology, Barts Cancer Institute, University of London, London EC1M 6BQ, UK
| | - Jonathan P. Moorman
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
- Hepatitis (HCV/HIV) Program, James H Quillen VA Medical Center, Johnson City 37614, TN, USA
| | - Zhi Q. Yao
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
- Hepatitis (HCV/HIV) Program, James H Quillen VA Medical Center, Johnson City 37614, TN, USA
| | - Shunbin Ning
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City 37614, TN, USA
| |
Collapse
|