Search

High expression of the epidermal growth factor receptor (EGFR) in breast carcinoma confers a growth advantage to the tumor cells. The EGFR tyrosine kinase inhibitor (EGFR-TKI) ZD1839 ('Iressa') has clinical activity in a wide range of tumor types, although the mechanism(s) by which it exerts its antitumor activity effects remain unclear. We analyzed the ability of ZD1839 to induce apoptosis and/or inhibition of proliferation in breast carcinoma cell lines, as well any association between this ability and the downregulation activity of MAPK and Akt, two recently proposed markers of ZD1839 activity. Proliferation, survival, and activation of Akt and MAPK were evaluated in six human breast cancer cell lines expressing various levels of EGFR and HER2 and exposed to ZD1839. EGFR and HER2 expression levels were determined using specific monoclonal antibodies and FACS analysis. The effects of ZD1839 were independent of EGFR expression levels, but were influenced by high HER2 expression. ZD1839 significantly reduced the rate of [3H]-thymidine incorporation in the four sensitive cell lines, while apoptosis was also induced in two of these cell lines. No correlation was found between the cytostatic or cytotoxic effects of ZD1839 and its ability to downregulate MAPK and Akt activity in the tumor cell lines. Our data suggest that the antitumor activity of ZD1839 is due to a cytostatic effect, and involves apoptosis induction in a subset of sensitive cells only, and that neither MAPK nor Akt is a reliable marker of ZD1839 activity., (Copyright 2003 Wiley-Liss, Inc.)

Purpose: Combining trastuzumab with doxorubicin and paclitaxel (AT) is attractive because of the activity of AT and survival improvements observed when trastuzumab is added to either agent in HER2-positive metastatic breast cancer. This pilot study evaluates the efficacy and cardiac tolerability of AT followed by paclitaxel with trastuzumab started with AT or paclitaxel alone and investigates pharmacokinetic interactions., Experimental Design: Two cohorts of 16 patients were enrolled. Cohort 1 received three cycles of AT (60/150 mg/m2) plus trastuzumab (4 mg/kg initial dose followed by 2 mg/kg), initiated concomitantly with doxorubicin, followed by nine cycles of paclitaxel (80 mg/m2) plus trastuzumab and then trastuzumab alone. Cohort 2 was treated with the same regimen, but trastuzumab was initiated with paclitaxel after AT. Cardiac function, pharmacokinetic interactions, and efficacy were evaluated., Results: Median baseline left ventricular ejection fraction (LVEF) was 62% (range, 57-74%) and 66% (range, 57-77%) in cohorts 1 and 2, respectively. Most patients had an absolute decrease in LVEF. Congestive heart failure was not observed. LVEF in three patients decreased to <50% but recovered despite continued treatment. Response rates were 87.5% in both cohorts (cohort 1:2 complete response, 12 partial response; cohort 2:3 complete response, 11 partial response). No unexpected side effects were observed. Pharmacokinetics of paclitaxel and its metabolites and of doxorubicin were similar without and with trastuzumab., Conclusions: Trastuzumab administered with AT followed by weekly paclitaxel alone is highly active whether trastuzumab is initiated with AT or paclitaxel. Congestive heart failure was not observed, and LVEF decreases were reversible. Further studies of this regimen are warranted.

Primary systemic therapy (PST) represents the standard of care in patients with locally advanced breast cancer. In addition, there is increasing information on PST in operable breast disease that supports the use of PST in routine practice. However, current regimens and techniques vary. To address this concern, a group of representatives from breast cancer clinical research groups in France, Germany, Italy, the United Kingdom, and the United States reviewed all available data on prospective randomized trials in this setting. Recommendations are made regarding terminology, indications, regimen, diagnosis before treatment, monitoring of efficacy, tumor localization, surgery, pathologic evaluation, and postoperative treatment.

Purpose: The feasibility and utility of assessing quality of life (QoL) and disease-related symptoms in patients with advanced cancer have been evaluated in two Phase I clinical trials of p.o. administered ZD1839 ('Iressa'), an epidermal growth factor receptor tyrosine kinase inhibitor, in patients with advanced cancer., Experimental Design: Functional Assessment of Cancer Therapy (FACT) questionnaires, including disease-specific subscales for lung, head and neck, colorectal, prostate, and ovarian cancer, were completed by patients in two open-label, Phase I, escalating multiple-dose safety and tolerability trials., Results: In 157 patients, 92% of whom had received prior therapy, compliance in returning FACT questionnaires was 87% (European/Australian trial) and 57% (United States trial). This did not appear to be influenced by dose level or tumor type. For patients with colorectal, prostate, or ovarian cancer, median QoL [FACT and Trial Outcome Index (TOI)] scores deteriorated over time. In contrast, for patients with non-small cell lung cancer (NSCLC) or head and neck cancer, median FACT and TOI scores did not deteriorate significantly, and in the United States trial, head and neck cancer scores improved significantly over time. In patients with NSCLC, symptom-related scores measured by the Lung Cancer Subscale of FACT-L appeared sensitive to clinical change., Conclusions: QoL (FACT-L) questionnaires were used successfully in the Phase I clinical trials of ZD1839. They appeared to be a sensitive tool to monitor clinical changes for the five tumor types in these trials and showed that ZD1839 has the potential to improve patients' QoL.