# PPP3CA

Source: https://onco.cc/targets/ppp3ca/  
OnCo record `ppp3ca` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

PPP3CA (Protein phosphatase 3 catalytic subunit alpha) is a gene whose normal job is to hold cell growth in check. The public catalogues list it as a tumour suppressor, and it is called a cancer driver by mutation analysis of patient cohorts. Tied to Gastric & gastro-oesophageal junction cancer.

## Summary

Calcium-dependent, calmodulin-stimulated protein phosphatase which plays an essential role in the transduction of intracellular Ca(2+)-mediated signals. Many of the substrates contain a PxIxIT motif and/or a LxVP motif. In response to increased Ca(2+) levels, dephosphorylates and activates phosphatase SSH1 which results in cofilin dephosphorylation.

IntOGen calls it a driver in 1 cohort (0 activating, 1 loss-of-function), covering Stomach Adenocarcinoma.

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: protein phosphatase 3 catalytic subunit alpha; Protein phosphatase 3 catalytic subunit alpha; CNA1; PPP2B; CALNA
- Tags: cancer-genes-wave
- Symbol: PPP3CA
- Class: tumor-suppressor
- Biology: Calcium-dependent, calmodulin-stimulated protein phosphatase which plays an essential role in the transduction of intracellular Ca(2+)-mediated signals. Many of the substrates contain a PxIxIT motif and/or a LxVP motif. In response to increased Ca(2+) levels, dephosphorylates and activates phosphatase SSH1 which results in cofilin dephosphorylation. In response to increased Ca(2+) levels following mitochondrial depolarisation, dephosphorylates DNM1L inducing DNM1L translocation to the mitochondrion. Positively regulates the CACNA1B/CAV2.2-mediated Ca(2+) release probability at hippocampal neuronal soma and synaptic terminals. Dephosphorylates heat shock protein HSPB1. Location: Cytoplasm; Cell membrane; Cell membrane, sarcolemma; Cytoplasm, myofibril, sarcomere, Z line (UniProt). Locus 4q24 (HGNC).
- Where found: Gastric & gastro-oesophageal junction cancer: IntOGen driver in 1 cohort (STAD)

## 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: IntOGen calls it a loss-of-function (LoF) driver in 1 cohort. Evidence tier "cohort-driver" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:9314: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:9314
- UniProt Q08209: https://www.uniprot.org/uniprotkb/Q08209/entry
- NCBI Gene 5530: https://www.ncbi.nlm.nih.gov/gene/5530
- Ensembl ENSG00000138814: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000138814

## Connected records

- collections: [IntOGen](https://onco.cc/collections/intogen/)
- cancers: [Gastric & gastro-oesophageal junction cancer](https://onco.cc/cancers/gastric/)

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JSON: https://onco.cc/api/v1/entities/ppp3ca.json