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Updated: Jul 13, 2026

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

Modulation of p21-activated kinase 1 alters the behavior of renal cell carcinoma

Gerald C O'Sullivan1, Mark Tangney1, Garret Casey1

  • 1Cork Cancer Research Center, Leslie C. Quick Jnr. Cancer Laboratories, Bioscience Institute and Mercy University Hospital, Cork, Ireland.

International Journal of Cancer
|July 11, 2007
PubMed

Insights

p21-activated kinase 1 (Pak1) is overexpressed and active in renal cell carcinoma (RCC). Inhibiting Pak1 reduces RCC proliferation and tumor growth, suggesting Pak1 as a therapeutic target for this refractory cancer.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • p21-activated kinase 1 (Pak1) regulates cell motility, proliferation, and angiogenesis.
  • Renal cell carcinoma (RCC) is often refractory to conventional chemotherapy and radiotherapy.
  • The role of Pak1 in RCC pathogenesis remains largely uninvestigated.

Purpose of the Study:

  • To investigate the expression, activity, and functional role of Pak1 in renal cell carcinoma.
  • To evaluate Pak1 as a potential therapeutic target for RCC.

Main Methods:

  • Pak1 expression, phosphorylation, and kinase activity were analyzed in RCC cell lines and human tissues.
  • Genetically engineered RCC cell lines expressing active or dominant-negative Pak1 mutants, or Pak1 siRNA, were created.
  • Cell proliferation, motility, anchorage-independent growth, and chemoresistance were assessed in vitro.
  • Tumorigenesis was evaluated in vivo using mouse models.

Main Results:

  • Pak1 expression and kinase activity were elevated in RCC tissues and cell lines, particularly in the membrane and nuclear fractions.
  • Overexpression of active Pak1 enhanced RCC cell proliferation, motility, and anchorage-independent growth.
  • Pak1 inhibition using dominant-negative mutants or siRNA abrogated these pro-tumorigenic effects and sensitized cells to 5-fluorouracil.
  • Pak1 inhibition significantly reduced tumor formation in vivo.

Conclusions:

  • Pak1 is constitutively active and plays a critical role in RCC progression.
  • Targeting Pak1 demonstrates significant anti-tumor activity in vitro and in vivo.
  • Pak1 represents a promising therapeutic target for treating advanced renal cell carcinoma.

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