CHLOROQUINE DOES NOT CANCEL E1A+cHa-Ras TRANSFORMANTS DEATH INDUCED BY mTOR KINASE INHIBITOR pp242

Tsitologiia
|September 7, 2018
PubMed

Insights

Combining chloroquine and pp242 effectively induces cell death in Ras-transformed cells. This approach targets both intact and senescent cells by inhibiting autophagy and mitochondrial function.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Oncology

Background:

  • Cellular senescence and autophagy are critical processes in aging and cancer.
  • Ras-transformed cells exhibit altered metabolic and survival pathways.
  • Understanding the interplay between autophagy and cell death is crucial for therapeutic development.

Purpose of the Study:

  • To investigate the impact of TORC1/C2 kinase inhibitor pp242 on cell viability and autophagy in control and senescent Ras-transformed rat embryo fibroblasts.
  • To evaluate the efficacy of combining pp242 with chloroquine, a lysosome inhibitor, in inducing cell death.

Main Methods:

  • Induction of cell senescence using sodium butyrate.
  • Treatment of fibroblasts with pp242 to trigger autophagy.
  • Assessment of mitochondrial activity and cell death pathways (mitophagy, apoptosis).
  • Combination treatment with pp242 and chloroquine.

Main Results:

  • pp242 significantly reduced mitochondrial activity and induced cell death via mitophagy and apoptosis in intact cells.
  • Senescent cells showed greater resistance to pp242 compared to control cells.
  • The combination of chloroquine and pp242 markedly reduced the viability of both intact and senescent Ras-transformed cells.
  • Chloroquine did not abolish the effects of pp242, suggesting a complex interplay.

Conclusions:

  • The combination of chloroquine and pp242 is a promising strategy for inducing cell death in Ras-transformed cells.
  • This combined approach effectively targets both non-senescent and senescent transformed cells.
  • Further research into this combination therapy could offer new avenues for cancer treatment.

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