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Activated mTOR/P70S6K signaling pathway is involved in insulinoma tumorigenesis

Han-Xiang Zhan1, Lin Cong, Yu-Pei Zhao

  • 1Department of General Surgery, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, P.R. China.

Journal of Surgical Oncology
|June 20, 2012
PubMed
Abstract

Insights

The mechanistic target of rapamycin (mTOR)/P70S6K pathway is implicated in insulinoma tumor growth. mTOR inhibitors like rapamycin and NVP-BEZ235 show promise for treating insulinoma.

Area of Science:

  • Oncology
  • Molecular Biology
  • Endocrinology

Background:

  • Insulinoma is a rare tumor with poorly understood pathogenesis.
  • The role of the mTOR signaling pathway in insulinoma tumorigenesis has not been previously studied.

Purpose of the Study:

  • To investigate the role of the mTOR/P70S6K signaling pathway in insulinoma development.
  • To evaluate the therapeutic potential of mTOR inhibitors in insulinoma.

Main Methods:

  • Immunohistochemistry and Western blotting were used to assess p-mTOR and p-P70S6K expression in insulinoma and normal pancreatic tissues.
  • In vitro studies utilized the INS-1 cell line treated with rapamycin or NVP-BEZ235 to analyze effects on cell proliferation, cell cycle, apoptosis, and insulin secretion.

Main Results:

  • Elevated expression of p-mTOR and p-P70S6K was observed in insulinoma tissues compared to normal pancreatic islets.
  • mTOR inhibitors significantly inhibited cell proliferation and insulin secretion while inducing apoptosis in INS-1 cells.
  • NVP-BEZ235 demonstrated a more potent effect on inhibiting proliferation and inducing apoptosis than rapamycin.

Conclusions:

  • The mTOR/P70S6K signaling pathway plays a crucial role in insulinoma tumorigenesis.
  • Rapamycin and NVP-BEZ235 represent potential novel therapeutic agents for insulinoma treatment.

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