There is no consensus on second-line treatment for women with metastatic or locally advanced breast cancer over-expressing HER-2 protein in whom treatment with a taxane + trastuzumab has failed. Capecitabine is one option. Adding lapatinib does not prolong survival. Trastuzumab emtansine (Kadcyla, Roche) has received EU marketing authorisation for use in this setting. It consists of two covalen...

OBJECTIVES The purpose of this study was to estimate heart failure (HF) and cardiomyopathy (CM) rates after adjuvant trastuzumab therapy and chemotherapy in a population of older women with early-stage breast cancer. BACKGROUND Newer biologic therapies for breast cancer such as trastuzumab have been reported to increase HF and CM in clinical trials, especially in combination with anthracyclin...

While results thus far demonstrate the clinical benefit of trastuzumab, some patients do not respond to this therapy. To identify a molecular predictor of trastuzumab benefit, we conducted whole-transcriptome analysis of primary HER2+ breast carcinomas obtained from patients treated with trastuzumab-containing therapies and correlated the molecular portrait with treatment benefit. The estimated...

INTRODUCTION Trastuzumab, an HER2-targeting agents, has shown efficacy in metastatic HER2-positive breast cancer patients. Single-agent clinical trials have evaluated therapeutic regimens using trastuzumab for metastatic breast cancer patients. The aim of our study is to evaluate the efficacy and safety of trastuzumab in combination with chemotherapy or hormone therapy in HER2-positive metastat...

Trastuzumab is a remarkably effective therapy for patients with human epidermal growth factor receptor 2 (HER2)--positive breast cancer (BC). However, not all women with high levels of HER2 benefit from trastuzumab. By integrating mRNA and protein expression data from Reverse-Phase Protein Array Analysis (RPPA) in HER2-positive BC, we developed gene expression metagenes that reflect pathway act...

Trastuzumab is currently used for patients with Her2(+) advanced gastric cancer. However, the response rate to trastuzumab among the patients is low. The molecular mechanisms underlying trastuzumab resistance in gastric cancer are unknown. Our in vitro data show that activation of β2-adrenergic receptor (β2-AR) triggered by catecholamine caused "targeting failure" of trastuzumab in gastric canc...

BACKGROUND Although trastuzumab therapy improves survival in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer, 40% of patients develop brain metastasis (BM) even when extracranial disease is under control. We studied whether trastuzumab therapy beyond or after BM was beneficial to patients with BM. PATIENTS AND METHODS The effect of trastuzumab o...

Background: Human epidermal growth factor receptor 2 (HER2) has a crucial role in several malignancies. The extracellular domain of HER2 (HER2-ECD) has been extensively employed as an important target in passive and active immunotherapy. Isolated recombinant prokaryotic HER2-ECD subdomains were previously found to be ineffective in inducing anti-tumor antibody response. Objective: To employ rec...

Primary and acquired resistance to the breast cancer drug trastuzumab (Herceptin) is a significant clinical problem. Here, we report enhanced activation of downstream signaling pathways emanating from the growth factor receptors erbB2, erbB3, and insulin-like growth factor-I receptor (IGF-IR) in trastuzumab-resistant breast cancer cells. Interactions between IGF-IR and erbB2 or erbB3 occur excl...

Although inactivation of the PTEN gene has been implicated in the development of resistance to the HER2 targeting antibody trastuzumab, the mechanisms mediating this resistance remain elusive. We generated trastuzumab resistant cells by knocking down PTEN expression in HER2 overexpressing breast cancer cell lines and demonstrate that development of trastuzumab resistance in these cells is media...