Family of RAS proteins (KRAS, NRAS, and HRAS) have been well described to cause oncogenic transformation.
- The expression and mutational status of RAS isoforms are critical in several cancers and are generally linked with a poorer prognosis when mutated.
RAS is one of the most frequently activated oncogenic drivers in human cancer. Mutations lock RAS in its GTP-bound active state, making signaling:
-Constitutive
-Growth-factor independent
-Resistant to normal feedback control
Key framing: RAS is a true driver oncogene, not just an amplifier.
Core Oncogenic Pathways Downstream of RAS
RAS sits at the apex of multiple essential signaling cascades:
a. MAPK Pathway (RAF–MEK–ERK)
-Drives proliferation
-Induces cell-cycle genes (Cyclin D, MYC, FOS/AP-1)
-Supports invasion and differentiation blockade
b. PI3K–AKT–mTOR
-Promotes survival and metabolic reprogramming
-Enhances resistance to apoptosis
-Supports protein synthesis and growth
c. RAL-GDS and Others
-Cytoskeletal remodeling
-Vesicle trafficking
-Metastatic behavior
Together, these create a multi-axis growth and survival program.
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