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Assessment of Mitochondrial Functions and Cell Viability in Renal Cells Overexpressing Protein Kinase C Isozymes
15:43

Assessment of Mitochondrial Functions and Cell Viability in Renal Cells Overexpressing Protein Kinase C Isozymes

Published on: January 7, 2013

PKCη is a negative regulator of AKT inhibiting the IGF-I induced proliferation

Galit Shahaf1, Noa Rotem-Dai, Gabriela Koifman

  • 1The Shraga Segal department of Microbiology and Immunology, Faculty of Health Science and the Cancer Research Center, Ben Gurion University of the Negev, Beer Sheva 84105, Israel.

Experimental Cell Research
|February 7, 2012
PubMed

Insights

Protein kinase C eta (PKCη) negatively regulates the PI3K-AKT pathway, a key pathway in breast cancer. Inhibiting PKCη increases AKT activity, impacting cancer cell proliferation and survival.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cell Signaling

Background:

  • The Phosphatidylinositol 3-kinase/AKT (PI3K-AKT) pathway is crucial for cancer cell survival and is frequently activated in breast cancer.
  • Targeting the PI3K-AKT pathway is a therapeutic strategy, as tumors with elevated AKT activity are sensitive to its inhibition.

Purpose of the Study:

  • To investigate the role of Protein Kinase C eta (PKCη) as a regulator of the PI3K-AKT signaling pathway in breast cancer.
  • To determine the effect of PKCη on AKT and ERK phosphorylation and its correlation with cell proliferation and apoptosis.

Main Methods:

  • Utilized MCF-7 breast adenocarcinoma cells to study the effects of PKCη expression and knockdown.
  • Assessed phosphorylation levels of AKT (Ser473) and ERK in response to IGF-I and PDGF stimulation.
  • Evaluated cell proliferation and apoptosis following UV irradiation in the presence and absence of PKCη and IGF-I.

Main Results:

  • PKCη expression inhibited IGF-I-induced AKT phosphorylation at Ser473 in MCF-7 cells.
  • Knockdown of PKCη led to increased AKT Ser473 phosphorylation.
  • PKCη modulated ERK phosphorylation differently depending on the stimulus (IGF-I vs. PDGF) and correlated with cell proliferation.
  • Both PKCη and IGF-I conferred additive protection against UV-induced apoptosis, with PKCη acting independently of AKT activation.

Conclusions:

  • PKCη acts as a negative regulator of the AKT signaling pathway, reducing breast cancer cell proliferation.
  • The expression status of PKCη influences breast cancer cell survival and apoptosis, suggesting its potential as a therapeutic target.

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