# TOP2B

Source: https://onco.cc/targets/top2b/  
OnCo record `top2b` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

TOP2B (DNA topoisomerase 2-beta) is an enzyme. The public catalogues list it as a drug target, and an approved or late-stage drug is recorded against it. Tied to Lung cancer, Neuroendocrine tumours, Breast cancer and 1 more.

## Summary

Key decatenating enzyme that alters DNA topology by binding to two double-stranded DNA molecules, generating a double-stranded break in one of the strands, passing the intact strand through the broken strand, and religating the broken strand. Plays a role in B-cell differentiation.

Open Targets scores its association with cancer at 0.69 (direct and indirect evidence; datatypes literature 0.93, animal model 0.39, genetic association 0.45, clinical 0.98).

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: DNA topoisomerase II beta; DNA topoisomerase 2-beta; top2beta; TOPIIB
- Tags: cancer-genes-wave
- Symbol: TOP2B
- Class: enzyme
- Biology: Key decatenating enzyme that alters DNA topology by binding to two double-stranded DNA molecules, generating a double-stranded break in one of the strands, passing the intact strand through the broken strand, and religating the broken strand. Plays a role in B-cell differentiation. Location: Nucleus, nucleolus; Nucleus, nucleoplasm; Nucleus (UniProt). Locus 3p24.2 (HGNC).
- Where found: Lung cancer: Open Targets association 0.58 with lung cancer (MONDO_0008903); Neuroendocrine tumours: Open Targets association 0.57 with neuroendocrine neoplasm (MONDO_0019496); Breast cancer: Open Targets association 0.55 with breast cancer (MONDO_0007254); Small-cell lung cancer: Open Targets association 0.56 with small cell lung carcinoma (MONDO_0008433)

## 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 0.98. Evidence tier "approved-drug" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:11990: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:11990
- UniProt Q02880: https://www.uniprot.org/uniprotkb/Q02880/entry
- NCBI Gene 7155: https://www.ncbi.nlm.nih.gov/gene/7155
- Ensembl ENSG00000077097: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000077097

## Connected records

- collections: [Open Targets Platform](https://onco.cc/collections/open-targets/)
- cancers: [Breast cancer (all types)](https://onco.cc/cancers/breast-cancer/), [Lung cancer (all types)](https://onco.cc/cancers/lung-cancer/), [Neuroendocrine tumours](https://onco.cc/cancers/neuroendocrine/), [Small-cell lung cancer](https://onco.cc/cancers/sclc/)

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JSON: https://onco.cc/api/v1/entities/top2b.json