PD-1-siRNA delivered by attenuated Salmonella enhances the antimelanoma effect of pimozide

Cell Death Dis. 2019 Feb 18;10(3):164. doi: 10.1038/s41419-019-1418-3.

Abstract

Melanoma is one of the most aggressive skin cancers worldwide. Although there has been much effort toward improving treatment options over the past few years, there remains an urgent need for effective therapy. Immunotherapy combined with chemotherapy has shown great promise in clinical trials. Here, we studied the cooperative effects of the small molecule drug pimozide, which has a therapeutic effect in melanoma, and RNA interference (RNAi) targeting PD-1, an important immune checkpoint molecule involved in tumor immune escape. PD-1 siRNA was delivered by attenuated Salmonella to melanoma-bearing mice in combination with pimozide. Our results demonstrated that the combination therapy had the optimal therapeutic effect on melanoma. The mechanisms underlying the efficacy involved the induction of apoptosis and an enhanced immune response. This study suggests that immunotherapy based on PD-1 inhibition combined with anticancer drugs could be a promising clinical strategy for the treatment of melanoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Agents / therapeutic use*
  • Apoptosis / drug effects
  • Combined Modality Therapy
  • Male
  • Melanoma, Experimental / drug therapy
  • Melanoma, Experimental / immunology
  • Melanoma, Experimental / therapy*
  • Mice
  • Mice, Inbred C57BL
  • Pimozide / therapeutic use*
  • Programmed Cell Death 1 Receptor / genetics*
  • Programmed Cell Death 1 Receptor / metabolism
  • RNA Interference
  • RNA, Small Interfering / genetics*
  • RNA, Small Interfering / metabolism
  • Salmonella / genetics
  • Salmonella / growth & development
  • Skin Neoplasms / drug therapy
  • Skin Neoplasms / immunology
  • Skin Neoplasms / therapy*
  • T-Lymphocytes / metabolism
  • Transplantation, Heterologous

Substances

  • Antineoplastic Agents
  • Programmed Cell Death 1 Receptor
  • RNA, Small Interfering
  • Pimozide