{"entity":{"id":"liv1","kind":"target","name":"LIV-1 (SLC39A6)","aka":[],"tldr":"LIV-1 is an oestrogen-regulated zinc transporter on most breast cancers; the ADC against it (ladiratuzumab vedotin) showed activity in triple-negative disease but was discontinued in 2024.","summary":"LIV-1 is expressed in >90% of breast cancers including ~70% of TNBC, and in prostate, melanoma and cervical cancers. Ladiratuzumab vedotin (SGN-LIV1A, MMAE payload) produced ~25-30% responses in pretreated metastatic breast cancer and was tested with pembrolizumab; Pfizer discontinued it in 2024 after acquiring Seagen. The target remains validated for next-generation ADCs and radioligands.","asOf":"2026-09-08","wikipedia":"https://en.wikipedia.org/wiki/SLC39A6","links":[{"label":"Ladiratuzumab vedotin (JCO 2019 abstract)","url":"https://doi.org/10.1200/JCO.2019.37.15_suppl.1094"}],"tags":["gap-fill","discontinued"],"related":[],"cancers":["tnbc","breast-hr-positive","prostate"],"sections":[],"technologies":["adc"],"targets":[],"drugs":[],"companies":["pfizer"],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["TNBC and prostate rates are not well characterised in peer-reviewed series with a stated denominator; the ~70% TNBC figure comes from sponsor assays reported in trial abstracts."],"symbol":"SLC39A6","role":[],"sources":[],"specificitySources":[],"hgnc":"HGNC:18607","ensembl":"ENSG00000141424","uniprot":"Q13433","entrez":"25800","firstDescribed":2001,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Green et al, 2001.","firstDescribedSource":"https://www.uniprot.org/uniprotkb/Q13433/entry","biology":"Zinc transporter of the ZIP family (SLC39A6) that localises to the plasma membrane, imports zinc and promotes EMT via STAT3/Snail; transcriptionally induced by oestrogen (hence LIV-1, from ER+ breast cancer lines).","whereFound":["Breast cancer (>90% HR+, ~70% TNBC)","Prostate cancer","Cervical, melanoma, pancreatic cancer (subsets)"],"targetClass":"surface-antigen","prevalence":[{"cancerId":"breast-hr-positive","pct":"37-43","measure":"IHC, high SLC39A6 expression (cytoplasmic H-score >160 in 37%; nuclear staining in 43%) in 670 unselected early breast cancers, enriched in ER+ tumours","source":"https://doi.org/10.1007/s10549-021-06336-y","note":"Assay- and cutoff-dependent: Seagen's SGN-LIV1A programme reported far higher any-expression rates with its own IHC assay"}]},"route":"/targets/liv1/","neighbours":{"cancer":[{"id":"breast-hr-positive","kind":"cancer","name":"HR-positive / HER2-negative breast cancer","route":"/cancers/breast-hr-positive/"},{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"technology":[{"id":"adc","kind":"technology","name":"Antibody-drug conjugate (ADC)","route":"/technologies/adc/"}],"company":[{"id":"pfizer","kind":"company","name":"Pfizer (incl. Seagen)","route":"/companies/pfizer/"}]}}