Abstract P4-10-31: Patterns of protein expression and signaling assessed by reverse phase protein array (RPPA) in estrogen-receptor negative (ER-), HER2-amplified breast cancer (BC) that was primary-refractory to preoperative (preop) HER2-directed therapy
| Autor: | Mariaelena Pierobon, Leslie S L Kim, Lance A. Liotta, Maren K Levin, Emanuel F. Petricoin, Elisa Baldelli, Joyce O'Shaughnessy |
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| Rok vydání: | 2020 |
| Předmět: |
Cancer Research
business.industry Reverse phase protein lysate microarray Cancer medicine.disease medicine.disease_cause Carboplatin chemistry.chemical_compound Breast cancer Oncology Docetaxel chemistry Trastuzumab medicine Cancer research Pertuzumab skin and connective tissue diseases Carcinogenesis business medicine.drug |
| Zdroj: | Cancer Research. 80:P4-10 |
| ISSN: | 1538-7445 0008-5472 |
| DOI: | 10.1158/1538-7445.sabcs19-p4-10-31 |
| Popis: | Background: ER- HER2+ BC is comprised of a heterogeneous mix of intrinsic BC subtypes which have differential responsiveness to preop HER2-directed therapies combined with chemotherapy. Patients (pts) with ER- HER2+ BC whose disease progressed while on or who had no response to preop HER2-directed therapy are uncommon and the mechanisms of resistance within this primary-refractory disease are unknown. We utilized RPPA-based protein pathway activation mapping to map the drug target signaling architecture in pts’ primary-refractory ER- HER2+ BCs to begin to assess mechanisms of resistance. Methods: Eight primary-refractory ER- HER2+ FFPE BC tissues obtained from 5 pts (preop biopsies n=4 and/or post-treatment surgical resection n=4) underwent laser capture microdissection to isolate pure tumor epithelium followed by RPPA-based analysis of the levels and/or activation/phosphorylation of approximately 130 key signaling proteins known to be involved in tumorigenesis and metastatic progression. Results: Pts were all treated with preop trastuzumab, pertuzumab, docetaxel, and carboplatin (TCHP) with no response and/or with progression of disease. Three pts also received preop doxorubicin/cyclophosphamide without response. RPPA-based analysis revealed that post-TCHP surgical samples had higher activation of a number of drug targets including receptor tyrosine kinases (RTK) such as MET and ALK, as well as HER family signaling proteins phospho-HER3 and phospho-EGFR compared to the matched pre-TCHP samples. Conclusions: In these ER- HER2+ BCs that were primary-refractory to preop TCHP, in those pts with patient-matched pre/post treatment samples, activation of several potential resistance pathways such as alternative RKT signaling as well as EGFR and HER3 signaling was observed. These data are hypothesis-generating and require exploration in additional ER- HER2+ primary-refractory tissues. Citation Format: Mariaelena Pierobon, Maren K Levin, Elisa Baldelli, Leslie SL Kim, Lance Liotta, Emanuel F Petricoin, Joyce O'Shaughnessy. Patterns of protein expression and signaling assessed by reverse phase protein array (RPPA) in estrogen-receptor negative (ER-), HER2-amplified breast cancer (BC) that was primary-refractory to preoperative (preop) HER2-directed therapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-31. |
| Databáze: | OpenAIRE |
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