MAPK3
Overview
MAPK3 (Mitogen-Activated Protein Kinase 3), also known as ERK1, is a serine/threonine kinase and central effector of the RAS/RAF/MEK/ERK signalling cascade. In cutaneous melanoma, MAPK3 phosphorylation (phospho-ERK1/2, T202/Y204) is highest in the RAS-mutant subtype by reverse-phase protein array (RPPA), reflecting hyperactivation of the MAPK pathway in this subclass.
Alterations observed in the corpus
- Phospho-ERK1/2 (T202/Y204) highest in RAS-mutant melanoma subtype by RPPA in the TCGA 333-sample multi-platform cutaneous melanoma cohort; MAPK3 and MAPK1 (ERK1/2) elevations reflect downstream MAPK pathway activity in NRAS/HRAS/KRAS-mutant tumours. PMID:26091043
- Identified as a marker of one of the three ILC mRNA subtypes (proliferative, reactive-like, immune-related) in a comprehensive molecular analysis of invasive lobular carcinoma PMID:26451490
Cancer types (linked)
- SKCM: Elevated phospho-ERK1/2 (T202/Y204) is the defining proteomic feature of the RAS-mutant melanoma subtype in the TCGA 333-sample cohort. PMID:26091043
Co-occurrence and mutual exclusivity
- MAPK3 (ERK1) co-elevated with MAPK1 (ERK2) in the RAS-mutant melanoma subtype; RAS-activating mutations (NRAS, HRAS, KRAS) drive the phospho-ERK signal. PMID:26091043
Therapeutic relevance
- Elevated phospho-ERK in RAS-mutant melanoma supports MEK/ERK inhibitor strategies; trametinib (MEK inhibitor) is FDA-approved for NRAS-mutant melanoma and the phospho-ERK high state defines the responsive population. PMID:26091043
Open questions
- Whether phospho-ERK level is a quantitative predictor of MEK inhibitor response magnitude beyond RAS mutation status alone is not addressed in this dataset. PMID:26091043
Sources
This page was processed by crosslinker on 2026-05-14. - PMID:26451490
This page was processed by crosslinker on 2026-05-14.