biostudies-otherNielsen TO5367-5374https://www.ebi.ac.uk/biostudies/studies/S-ECPF-SMDB-2863EurocanPlatformExpression profiling studies have classified breast carcinomas into luminal, normal breast-like, HER2 expressing and basal-like groups, with the latter two associated with poor outcomes. This study's objectives were to define an immunohistochemical profile that identifies basal-like tumors, to identify the presence of potential drug targets, and to determine the prognostic significance of the basal-like immunophenotype in a large series with long-term follow-up. On a panel of 21 breast tumors with basal-like expression profiles, we determined that this subtype was immunohistochemically negative for estrogen receptor and HER2, but positive for basal cytokeratins, HER1 and/or c-KIT. Using breast carcinoma tissue microarrays representing 930 patients with 17.4 years mean follow-up, basal cytokeratin expression was associated with decreased disease-specific survival. HER1 expression was observed in 54% of cases positive for basal cytokeratins (vs. 11% of negative cases) and was associated with poor survival independent of nodal status and size. c-KIT expression was more common in basal-like tumors than in other breast cancers, but did not influence prognosis. A panel of four antibodies (ER, HER1, HER2, and cytokeratin 5/6) can accurately identify basal-like tumors and suggests candidate drugs for therapies targeting HER1 or c-KIT.biostudies-othertranscription profiling by arrayEurocanPlatformUnknown10Clinical cancer research : an official journal of the American Association for Cancer ResearchHomo sapiensLivasy CHu ZRagaz JKaraca GGilks CBNielsen TOPerou CMvan de Rijn MGown AMHernandez-Boussard TJensen KHsu FDDressler LCowan DCheang MAkslen LAfalseTranscription profiling of human breast carcinoma tissues representing 930 patients with 17.4 years mean follow-up, basal cytokeratin expression was associated with decreased disease-specific survivalExpression profiling studies have classified breast carcinomas into luminal, normal breast-like, HER2 expressing and basal-like groups, with the latter two associated with poor outcomes. This study's objectives were to define an immunohistochemical profile that identifies basal-like tumors, to identify the presence of potential drug targets, and to determine the prognostic significance of the basal-like immunophenotype in a large series with long-term follow-up. On a panel of 21 breast tumors with basal-like expression profiles, we determined that this subtype was immunohistochemically negative for estrogen receptor and HER2, but positive for basal cytokeratins, HER1 and/or c-KIT. Using breast carcinoma tissue microarrays representing 930 patients with 17.4 years mean follow-up, basal cytokeratin expression was associated with decreased disease-specific survival. HER1 expression was observed in 54% of cases positive for basal cytokeratins (vs. 11% of negative cases) and was associated with poor survival independent of nodal status and size. c-KIT expression was more common in basal-like tumors than in other breast cancers, but did not influence prognosis. A panel of four antibodies (ER, HER1, HER2, and cytokeratin 5/6) can accurately identify basal-like tumors and suggests candidate drugs for therapies targeting HER1 or c-KIT.2016-04-14T14:52:24Z2004 Aug2016-04-14T14:52:24Z2016-04-14T14:52:24ZS-ECPF-SMDB-2863E-SMDB-2863EFO_0000635EFO_0000305E-SMDB-2863