biostudies-literatureUnknown22(1)Vitale SR<h4>Background</h4>In breast cancer (BC), recurrent fusion genes of estrogen receptor alpha (ESR1) and AKAP12, ARMT1 and CCDC170 have been reported. In these gene fusions the ligand binding domain of ESR1 has been replaced by the transactivation domain of the fusion partner constitutively activating the receptor. As a result, these gene fusions can drive tumor growth hormone independently as been shown in preclinical models, but the clinical value of these fusions have not been reported. Here, we studied the prognostic and predictive value of different frequently reported ESR1 fusion transcripts in primary BC.<h4>Methods</h4>We evaluated 732 patients with primary BC (131 ESR1-negative and 601 ESR1-positive cases), including two ER-positive BC patient cohorts: one cohort of 322 patients witBMC cancer165https://www.ebi.ac.uk/biostudies/studies/S-EPMC8840267biostudies-literatureThe prognostic and predictive value of ESR1 fusion gene transcripts in primary breast cancer.PMC8840267Beaufort CMRuigrok-Ritstier KVigneri PVitale SRTimmermans AMSieuwerts AMFoekens RTrapman-Jansen AMACMartens JWMSleijfer SJansen MPHMfalseThe prognostic and predictive value of ESR1 fusion gene transcripts in primary breast cancer.<h4>Background</h4>In breast cancer (BC), recurrent fusion genes of estrogen receptor alpha (ESR1) and AKAP12, ARMT1 and CCDC170 have been reported. In these gene fusions the ligand binding domain of ESR1 has been replaced by the transactivation domain of the fusion partner constitutively activating the receptor. As a result, these gene fusions can drive tumor growth hormone independently as been shown in preclinical models, but the clinical value of these fusions have not been reported. Here, we studied the prognostic and predictive value of different frequently reported ESR1 fusion transcripts in primary BC.<h4>Methods</h4>We evaluated 732 patients with primary BC (131 ESR1-negative and 601 ESR1-positive cases), including two ER-positive BC patient cohorts: one cohort of 322 patients wit2022-01-01T00:00:00Z2022 Feb2025-04-04T14:58:41.861Z2025-02-19T03:58:09.926ZS-EPMC88402673515127610.1186/s12885-022-09265-1