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Updated: Aug 9, 2026
07:49
Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods
Published on: July 17, 2019
p21ras: an oncoprotein functioning in growth factor-induced signal transduction
1Laboratory for Physiological Chemistry, Universiteit Utrecht, The Netherlands.
European Journal of Cancer (Oxford, England : 1990)
|July 1, 1995
Summary
Mutated p21ras (RAS oncogene family) proteins are constitutively active in 50% of colorectal tumors, driving aberrant cell signaling. Understanding these pathways is crucial for cancer research.
Area of Science:
- Molecular Biology
- Cellular Signaling
- Oncology
Background:
- p21ras (RAS oncogene family) is a GTPase acting as a molecular switch in signal transduction.
- Growth factors activate p21ras, which is frequently mutated in colorectal tumors, leading to constitutive activity.
Purpose of the Study:
- To elucidate the signaling pathways involving p21ras.
- To understand the role of mutated p21ras in colorectal tumorigenesis.
Main Methods:
- Analysis of intracellular signal transduction pathways.
- Investigating the interaction of p21ras with downstream effectors like raf1.
- Studying kinase cascade activation.
Main Results:
- Ligand binding to growth factor receptors activates guanine nucleotide exchange factors, leading to GTP-bound p21ras.
- GTP-bound p21ras activates raf1, initiating a kinase cascade.
- This cascade mediates cellular responses and is part of a complex signaling network.
Conclusions:
- Mutated p21ras plays a significant role in colorectal cancer by maintaining constitutive signaling.
- The p21ras-raf1 pathway is a key component of integrated cellular signaling networks.
- Further research into these pathways may reveal therapeutic targets for colorectal cancer.
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