# MAPK8

Source: https://onco.cc/targets/mapk8/  
OnCo record `mapk8` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

MAPK8 (Mitogen-activated protein kinase 8) is a protein kinase, an enzyme that switches other proteins on by adding phosphate groups. The public catalogues list it as a drug target, and clinical evidence ties its variants to diagnosis, prognosis or drug response.

## Summary

Serine/threonine-protein kinase involved in various processes such as cell proliferation, differentiation, migration, transformation and programmed cell death. Extracellular stimuli such as pro-inflammatory cytokines or physical stress stimulate the stress-activated protein kinase/c-Jun N-terminal kinase (SAP/JNK) signalling pathway. In this cascade, two dual specificity kinases MAP2K4/MKK4 and MAP2K7/MKK7 phosphorylate and activate MAPK8/JNK1.

Open Targets scores its association with cancer at 0.58 (direct and indirect evidence; datatypes clinical 0.06, affected pathway 0.89, literature 0.99, genetic association 0.00, animal model 0.51).

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: mitogen-activated protein kinase 8; Mitogen-activated protein kinase 8; JNK1; SAPK1; PRKM8
- Tags: cancer-genes-wave
- Symbol: MAPK8
- Class: kinase
- Biology: Serine/threonine-protein kinase involved in various processes such as cell proliferation, differentiation, migration, transformation and programmed cell death. Extracellular stimuli such as pro-inflammatory cytokines or physical stress stimulate the stress-activated protein kinase/c-Jun N-terminal kinase (SAP/JNK) signalling pathway. In this cascade, two dual specificity kinases MAP2K4/MKK4 and MAP2K7/MKK7 phosphorylate and activate MAPK8/JNK1. In turn, MAPK8/JNK1 phosphorylates a number of transcription factors, primarily components of AP-1 such as JUN, JDP2 and ATF2 and thus regulates AP-1 transcriptional activity. Phosphorylates the replication licensing factor CDT1, inhibiting the interaction between CDT1 and the histone H4 acetylase HBO1 to replication origins. Loss of this interaction abrogates the acetylation required for replication initiation. Location: Cytoplasm; Nucleus; Synapse (UniProt). Locus 10q11.22 (HGNC).

## Notes

- Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: Open Targets known-drug datatype score 0.06. Evidence tier "clinical-evidence" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:6881: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:6881
- UniProt P45983: https://www.uniprot.org/uniprotkb/P45983/entry
- NCBI Gene 5599: https://www.ncbi.nlm.nih.gov/gene/5599
- Ensembl ENSG00000107643: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000107643

## Connected records

- collections: [Open Targets Platform](https://onco.cc/collections/open-targets/)

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JSON: https://onco.cc/api/v1/entities/mapk8.json