# S100B

Source: https://onco.cc/targets/s100b/  
OnCo record `s100b` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

S100B (S100 calcium binding protein B) is a gene. The public catalogues list it as a biomarker, and clinical evidence ties its variants to diagnosis, prognosis or drug response.

## Summary

Small zinc- and- and calcium-binding protein that is highly expressed in astrocytes and constitutes one of the most abundant soluble proteins in brain. Weakly binds calcium but binds zinc very tightly-distinct binding sites with different affinities exist for both ions on each monomer. Physiological concentrations of potassium ion antagonise the binding of both divalent cations, especially affecting high-affinity calcium-binding sites.

CIViC holds 1 clinical evidence item and 0 assertions across 1 variant.

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: S100 calcium binding protein B; S100beta
- Tags: cancer-genes-wave
- Symbol: S100B
- Class: other
- Biology: Small zinc- and- and calcium-binding protein that is highly expressed in astrocytes and constitutes one of the most abundant soluble proteins in brain. Weakly binds calcium but binds zinc very tightly-distinct binding sites with different affinities exist for both ions on each monomer. Physiological concentrations of potassium ion antagonise the binding of both divalent cations, especially affecting high-affinity calcium-binding sites. Acts as a neurotrophic factor that promotes astrocytosis and axonal proliferation. Involved in innervation of thermogenic adipose tissue by acting as an adipocyte-derived neurotrophic factor that promotes sympathetic innervation of adipose tissue. Binds to and initiates the activation of STK38 by releasing autoinhibitory intramolecular interactions within the kinase. Location: Cytoplasm; Nucleus; Secreted (UniProt). Locus 21q22.3 (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: CIViC holds 1 clinical evidence items on its variants. Evidence tier "clinical-evidence" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.
- Diseases the sources name that have no OnCo cancer page yet, so they are not linked: Lipofibromatosis-like Neural Tumour.

## Sources

- HGNC HGNC:10500: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:10500
- UniProt P04271: https://www.uniprot.org/uniprotkb/P04271/entry
- NCBI Gene 6285: https://www.ncbi.nlm.nih.gov/gene/6285
- Ensembl ENSG00000160307: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000160307

## Connected records

- collections: [CIViC](https://onco.cc/collections/civic/)

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JSON: https://onco.cc/api/v1/entities/s100b.json