Therapeutic potential of CPI-613 for targeting tumorous mitochondrial energy metabolism and inhibiting autophagy in clear cell sarcoma

PLoS One. 2018 Jun 7;13(6):e0198940. doi: 10.1371/journal.pone.0198940. eCollection 2018.

Abstract

Clear cell sarcoma (CCS) is an aggressive type of soft tissue tumor that is associated with high rates of metastasis. In the present study, we found that CPI-613, which targets tumorous mitochondrial energy metabolism, induced autophagosome formation followed by lysosome fusion in HS-MM CCS cells in vitro. Interestingly, CPI-613 along with chloroquine, which inhibits the fusion of autophagosomes with lysosomes, significantly induced necrosis of HS-MM CCS cell growth in vitro. Subsequently, we established a murine orthotropic metastatic model of CCS and evaluated the putative suppressive effect of a combination of CPI-613 and chloroquine on CCS progression. Injection of HS-MM into the aponeuroses of the thigh, the most frequently affected site in CCS, resulted in massive metastasis in SCID-beige mice. By contrast, intraperitoneal administration of CPI-613 (25 mg/kg) and chloroquine (50 mg/kg), two days a week for two weeks, significantly decreased tumor growth at the injection site and abolished metastasis. The present results imply the inhibitory effects of a combination of CPI-613 and chloroquine on the progression of CCS.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autophagy / drug effects*
  • Caprylates / pharmacology*
  • Cell Line, Tumor
  • Chloroquine
  • Drug Delivery Systems / methods*
  • Energy Metabolism / drug effects*
  • Humans
  • Mice
  • Mice, SCID
  • Mitochondria / metabolism*
  • Mitochondria / pathology
  • Sarcoma, Clear Cell / drug therapy*
  • Sarcoma, Clear Cell / metabolism
  • Sarcoma, Clear Cell / pathology
  • Sulfides / pharmacology*
  • Xenograft Model Antitumor Assays

Substances

  • Caprylates
  • Sulfides
  • Chloroquine
  • devimistat

Grants and funding

This study was supported by grants from the Ministry of Education of Japan (Grant nos. KAKEN 15K08361 to T.T. and 17K15642 to C.S.). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.