Related Experiment Video

Updated: May 12, 2026

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells
06:09

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells

Published on: June 7, 2019

P21-activated kinase 1 (PAK1) as a therapeutic target in BRAF wild-type melanoma

Christy C Ong1, Adrian M Jubb, Diana Jakubiak

  • 1Department of Translational Oncology Genentech, MS 50, 1 DNA Way, South San Francisco, CA 94080, USA.

Journal of the National Cancer Institute
|March 29, 2013
PubMed
Abstract

Insights

Targeting p21-activated kinases (PAKs) shows promise for BRAF wild-type melanoma. PAK1 inhibition effectively reduced tumor growth and MAPK signaling in preclinical models, offering a new therapeutic avenue.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cancer Genetics

Background:

  • BRAF-mutant melanoma shows good response to targeted therapies like vemurafenib and dabrafenib.
  • A significant unmet need exists for effective treatments for BRAF wild-type melanoma.
  • p21-activated kinases (PAKs) are investigated for their role in melanoma progression.

Purpose of the Study:

  • To investigate the role of PAK1 in melanoma, particularly in BRAF wild-type tumors.
  • To assess the therapeutic potential of PAK1 inhibition in melanoma models.

Main Methods:

  • Assessed PAK1 genomic copy number and protein expression in human melanoma tissues.
  • Utilized RNA interference and a selective PAK inhibitor (PF-3758309) to inhibit PAK1 in melanoma cell lines.
  • Evaluated tumor growth and MAPK pathway activation in vivo using xenograft models in mice.

Main Results:

  • PAK1 protein expression was common in melanomas and inversely associated with BRAF mutations.
  • Focal copy number gain of PAK1 was observed and mutually exclusive with BRAF mutations.
  • PAK1 inhibition reduced melanoma cell proliferation and migration, and decreased tumor growth in BRAF wild-type xenografts, also inhibiting MAPK signaling.

Conclusions:

  • PAK1 plays a functional role in BRAF wild-type melanoma.
  • PAK inhibitors represent a potential therapeutic strategy for BRAF wild-type melanoma.

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