Basal Protein Expression Is Associated With Worse Outcome and Trastuzamab Resistance in HER2+ Invasive Breast Cancer

• Published in: Clinical breast cancer Vol. 15; no. 6; pp. 448 - 457.e2
• Main Authors: Chung, Alice, Choi, Michael, Han, Bing-chen, Bose, Shikha, Zhang, Xiao, Medina-Kauwe, Lali, Sims, Jessica, Murali, Ramachandran, Taguiam, Michael, Varda, Marian, Schiff, Rachel, Giuliano, Armando, Cui, Xiaojiang
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-12-2015
• Subjects: Adult; Aged; Aged, 80 and over; Antineoplastic Agents - therapeutic use; Basal breast cancer; Biomarkers, Tumor - analysis; Breast Neoplasms - metabolism; Breast Neoplasms - mortality; Breast Neoplasms - pathology; CK14; CK5/6; Disease-Free Survival; Drug Resistance, Neoplasm - physiology; EGFR; Female; Hematology, Oncology and Palliative Medicine; HER2 overexpression; Humans; Immunoblotting; Immunohistochemistry; Kaplan-Meier Estimate; Keratins - analysis; Keratins - biosynthesis; Middle Aged; Neoplasm Invasiveness; Obstetrics and Gynecology; Phenotype; Proportional Hazards Models; Receptor, Epidermal Growth Factor - analysis; Receptor, Epidermal Growth Factor - biosynthesis; Receptor, ErbB-2 - antagonists & inhibitors; Trastuzumab - therapeutic use; Treatment Outcome; CK14; HER2 overexpression; Basal breast cancer; EGFR; CK5/6
• ISSN: 1526-8209; 1938-0666
• DOI: 10.1016/j.clbc.2015.06.001

Micro-Abstract We evaluated basal protein expression in patients with HER2-overexpressing (HER2+ ) tumors treated with trastuzamab and found that expression of epidermal growth factor receptor and cytokeratin 5/6 was associated with worse survival. We investigated basal protein expression in HER2+ cell lines and found that basal cells were more resistant to trastuzamab than nonbasal cells and Akt signaling might be critical in the mechanism of this resistance.