Suppression of KSHV lytic replication and primary effusion lymphoma by selective RNF5 inhibition

PLoS Pathog. 2023 Jan 19;19(1):e1011103. doi: 10.1371/journal.ppat.1011103. eCollection 2023 Jan.

Abstract

Primary effusion lymphoma (PEL), a rare aggressive B-cell lymphoma in immunosuppressed patients, is etiologically associated with oncogenic γ-herpesvirus infection. Chemotherapy is commonly used to treat PEL but usually results in poor prognosis and survival; thus, novel therapies and drug development are urgently needed for PEL treatment. Here, we demonstrated that inhibition of Ring finger protein 5 (RNF5), an ER-localized E3 ligase, suppresses multiple cellular pathways and lytic replication of Kaposi sarcoma-associated herpesvirus (KSHV) in PEL cells. RNF5 interacts with and induces Ephrin receptors A3 (EphA3) and EphA4 ubiquitination and degradation. RNF5 inhibition increases the levels of EphA3 and EphA4, thereby reducing ERK and Akt activation and KSHV lytic replication. RNF5 inhibition decreased PEL xenograft tumor growth and downregulated viral gene expression, cell cycle gene expression, and hedgehog signaling in xenograft tumors. Our study suggests that RNF5 plays the critical roles in KSHV lytic infection and tumorigenesis of primary effusion lymphoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • DNA-Binding Proteins / metabolism
  • Hedgehog Proteins / metabolism
  • Herpesviridae Infections*
  • Herpesvirus 8, Human* / genetics
  • Humans
  • Lymphoma, Primary Effusion*
  • Sarcoma, Kaposi*
  • Signal Transduction
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism
  • Virus Replication

Substances

  • Hedgehog Proteins
  • RNF5 protein, human
  • DNA-Binding Proteins
  • Ubiquitin-Protein Ligases

Grants and funding

This work was supported by grants from the National Natural Science Foundation of China (grant number 81871643 and 32061143008) to E.K. and the National Natural Science Foundation of China (grant number 81971928) to X.L. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.