Activation of mTOR signaling in medullary and aggressive papillary thyroid carcinomas

Maria A Kouvaraki1, Chrysoula Liakou, Adriani Paraschi

  • 1Department of Surgery, University of Thessaly, University Hospital of Larissa, Larissa, Greece.

Surgery
|December 6, 2011
PubMed
Abstract

Insights

Mammalian target of rapamycin (mTOR) pathway is activated in aggressive thyroid cancers. Targeting mTOR with rapamycin may offer a new therapeutic strategy for these aggressive tumors.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cancer Research

Background:

  • Mammalian target of rapamycin (mTOR) signaling is implicated in thyroid carcinogenesis.
  • Investigating mTOR pathway proteins in thyroid tumors is crucial for understanding cancer progression.

Purpose of the Study:

  • To examine the expression and activation of mTOR signaling proteins in thyroid carcinoma.
  • To correlate mTOR pathway activity with tumor histology and aggressiveness.

Main Methods:

  • Immunohistochemistry and Western blot analysis of 50 thyroid cancer specimens.
  • Analysis of primary tumor cell cultures and pharmacologic studies with rapamycin.

Main Results:

  • High eIF4E expression in medullary (MTC) and aggressive papillary thyroid carcinomas (PTC).
  • Elevated p-rpS6, p-4EBP1, 4EBP1, and eIF4E in aggressive PTC and MTC cells.
  • Rapamycin treatment reduced MTC cell growth and induced cell death.

Conclusions:

  • mTOR signaling is activated in aggressive thyroid cancers (PTC and MTC).
  • The mTOR pathway is a potential therapeutic target for aggressive thyroid carcinomas.

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