OnCo

Topoisomerase I (TOP1)

Short target page →

The enzyme that nicks one DNA strand to relieve twisting while DNA is copied. Camptothecins and the payloads of several antibody-drug conjugates trap it on the DNA so the nick becomes a permanent break when the cell replicates. This dossier gathers the 0 products (0 approved), 0 trials, 0 pathways and 0 resistance routes in the corpus that involve it, with external identifiers so it can be joined to UniProt, ChEMBL, Open Targets and the rest of biology.

Biology

Type IB topoisomerase that relieves torsional stress during replication and transcription; trapped as a covalent cleavage complex by camptothecins.

Where it is found
  • Expressed in all dividing cells; relevant wherever camptothecin or topoisomerase I payload drugs are used
Class: enzyme · Gene: TOP1 · Facts checked 2026-09-04 · Target page

External identifiers

Built from HGNC, Ensembl, UniProt and ChEMBL ids

Products by modality and phase

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No product in the corpus is aimed at this target yet.

No trial in the corpus names this target or one of its products.

Resistance routes

Unaddressed routes →

The resistance atlas has no route that names this target.

No pathway diagram carries this target as a node.

Companion diagnostics

Assay registry →

No companion diagnostic in the registry measures this target.

Preclinical models

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No model entry for this target yet; check the cancer entries on the models page.

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Literature

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Query for this target: (TITLE:"Topoisomerase I" OR ABSTRACT:"Topoisomerase I" OR TITLE:"TOP1" OR ABSTRACT:"TOP1") AND (cancer OR tumor OR tumour OR oncology OR carcinoma OR lymphoma OR leukemia OR leukaemia OR myeloma OR sarcoma OR melanoma OR glioma). Results are unfiltered search hits about Topoisomerase I (TOP1), not a curated reading list.

Export

The dossier as machine-readable JSON: identifiers from HGNC, Ensembl, UniProt and ChEMBL, products with status, trials, pathways, hotspots, open questions and assays. The full entity record is in the open API at /api/v1/entities/top1.json. Licence CC BY-NC 4.0.