Purpose:The epidermal growth factor receptor (EGFR) autocrine signaling pathway is involved in cancer development and progression. EGFR inhibitors such as C225 (cetuximab), a chimeric human-mouse anti-EGFR monoclonal antibody, and ZD1839 (gefitinib), a small molecule EGFR-selective tyrosine kinase inhibitor, are in advanced clinical development. The potential emergence of cancer cell resistance in EGFR-expressing cancers treated with EGFR inhibitors could determine lack of activity of these drugs in some cancer patients. Vascular endothelial growth factor (VEGF) is secreted by cancer cells and plays a key role in the regulation of tumor-induced endothelial cell proliferation and permeability. ZD6474 is a small molecule VEGF flk-1/KDR (VEGFR-2) tyrosine kinase inhibitor that also demonstrates inhibitory activity against EGFR tyrosine kinase.Experimental Design: The antitumor activity of ZD1839, C225, and ZD6474 was tested in athymic mice bearing human GEO colon cancer xenografts. GEO cell lines resistant to EGFR inhibitors were established from GEO xenografts growing in mice treated chronically with ZD1839 or C225. Expression of EGFR was evaluated by flow cytometry. Expression of various proteins involved in intracellular cell signaling was assessed by Western blotting. Tumor growth data were evaluated for statistical significance using the Student's t test. All Ps were two-sided.Results: Although chronic administration of optimal doses of C225 or ZD1839 efficiently blocked GEO tumor growth in the majority of mice, tumors slowly started to grow within 80 -90 days, despite continuous treatment. In contrast, continuous treatment of mice bearing established GEO xenografts with ZD6474 resulted in efficient tumor growth inhibition for the entire duration of dosing (up to 150 days). ZD6474 activity was also determined in mice pretreated with ZD1839 or C225. When GEO growth was apparent after 4 weeks of treatment with EGFR inhibitors, mice were either re-treated with EGFR inhibitors or treated with ZD6474. GEO tumor growth was blocked only in mice treated with ZD6474, whereas tumor progression was observed in mice re-treated with C225 or ZD1839. GEO tumors growing during treatment with C225 or with ZD1839 were established as cell lines (GEO-C225-RES and GEO-ZD1839-RES, respectively). Cell membrane-associated EGFR expression was only slightly reduced in these cell lines compared with parental GEO cells. Western blotting revealed no major change in the expression of the EGFR ligand transforming growth factor ␣ of bcl-2, bcl-xL, p53, p27, MDM-2, akt, activated phospho-akt, or mitogen-activated protein kinase. However, both GEO-C225-RES and GEO-ZD1839-RES cells exhibited a 5-10-fold increase in activated phospho-mitogen-activated protein kinase and in the expression of cyclooxygenase-2 and of VEGF compared with GEO cells. GEO-C225-RES and GEO-ZD1839-RES growth as xenografts in nude mice was not significantly affected by treatment with either C225 or ZD1839 but was efficiently inhibited by ZD6474.Conclusions: Long-t...
Novel antibody-drug conjugates against HER2 are showing high activity in HER2-negative breast cancer (BC) with low HER2 expression (i.e., 1+ or 2+ and lack of ERBB2 amplification). However, the clinical and molecular features of HER2-low BC are yet to be elucidated. Here, we collected retrospective clinicopathological and PAM50 data from 3,689 patients with HER2-negative disease and made the following observations. First, the proportion of HER2-low was higher in HR-positive disease (65.4%) than triple-negative BC (TNBC, 36.6%). Second, within HR-positive disease, ERBB2 and luminal-related genes were more expressed in HER2-low than HER2 0. In contrast, no gene was found differentially expressed in TNBC according to HER2 expression. Third, within HER2-low, ERBB2 levels were higher in HR-positive disease than TNBC. Fourth, HER2-low was not associated with overall survival in HR-positive disease and TNBC. Finally, the reproducibility of HER2-low among pathologists was suboptimal. This study emphasizes the large biological heterogeneity of HER2-low BC, and the need to implement reproducible and sensitive assays to measure low HER2 expression.
ER+/PR- tumors express higher levels of HER-1 and HER-2 and display more aggressive features than ER+/PR+ tumors. As in laboratory models, lack of PR expression in ER+ tumors may be a surrogate marker of aberrant growth factor signaling that could contribute to the tamoxifen resistance observed in these tumors.
The clinical outcome of cirrhotic patients with hepatocellular carcinoma (HCC) depends both on the residual liver function and tumor characteristics. However, the relative prognostic weight of these variables is not well defined. The aims of this study were to verify the value of known prognostic factors and to devise a prognostic index more sensitive than the commonly used Okuda stage. A retrospective analysis of the cases of HCC diagnosed at 16 Italian institutions from 1990 to 1992 was performed. Overall survival was the only end point used in the analysis. The Cox model, stratified by locoregional treatment, was used for multivariate analyses. The final model was derived from 10 randomly chosen training samples, and the prognostic validity of the Cancer of the Liver Italian Program (CLIP) score was assessed on the corresponding testing samples. Four hundred thirty-five cases of HCC were collected. As of January 1997, 313 patients (72%) were deceased. Overall median survival was 20 months. At multivariate analysis, independent predictive factors of survival were Child-Pugh stage, tumor morphology, alpha-fetoprotein (AFP), and portal vein thrombosis. A simple scoring system (CLIP score) was thus produced, assigning linear scores (0/1/2) to the covariates. Compared with Okuda stage, the CLIP score, structured as a six-category tool, has a greater discriminant ability, revealing a class of patients with an impressively more favorable prognosis and another class with a relatively shorter life expectancy. The CLIP score is a new prognostic system that accounts for both liver function and tumor characteristics. It is easy to calculate and appears to give more precise information than the Okuda stage.
Purpose Information about symptomatic toxicities of anticancer treatments is not based on direct report by patients, but rather on reports by clinicians in trials. Given the potential for under-reporting, our aim was to compare reporting by patients and physicians of six toxicities (anorexia, nausea, vomiting, constipation, diarrhea, and hair loss) within three randomized trials. Patients and Methods In one trial, elderly patients with breast cancer received adjuvant chemotherapy; in two trials, patients with advanced non–small-cell lung cancer received first-line treatment. Toxicity was prospectively collected by investigators (graded by National Cancer Institute Common Toxicity Criteria [version 2.0] or Common Terminology Criteria for Adverse Events [version 3]). At the end of each cycle, patients completed the European Organisation for Research and Treatment of Cancer quality-of-life questionnaires, including toxicity-related symptom items. Possible answers were “not at all,” “a little,” “quite a bit,” and “very much.” Analysis was limited to the first three cycles. For each toxicity, agreement between patients and physicians and under-reporting by physicians (ie, toxicity reported by patients but not reported by physicians) were calculated. Results Overall, 1,090 patients (2,482 cycles) were included. Agreement between patients and physicians was low for all toxicities. Toxicity rates reported by physicians were always lower than those reported by patients. For patients who reported toxicity (any severity), under-reporting by physicians ranged from 40.7% to 74.4%. Examining only patients who reported “very much” toxicity, under-reporting by physicians ranged from 13.0% to 50.0%. Conclusion Subjective toxicities are at high risk of under-reporting by physicians, even when prospectively collected within randomized trials. This strongly supports the incorporation of patient-reported outcomes into toxicity reporting in clinical trials.
Background: In the phase III IMpassion130 trial, combining atezolizumab with first-line nanoparticle albumin-boundpaclitaxel for advanced triple-negative breast cancer (aTNBC) showed a statistically significant progression-free survival (PFS) benefit in the intention-to-treat (ITT) and programmed death-ligand 1 (PD-L1)-positive populations, and a clinically meaningful overall survival (OS) effect in PD-L1-positive aTNBC. The phase III KEYNOTE-355 trial adding pembrolizumab to chemotherapy for aTNBC showed similar PFS effects. IMpassion131 evaluated first-line atezolizumabepaclitaxel in aTNBC. Patients and methods: Eligible patients [no prior systemic therapy or 12 months since (neo)adjuvant chemotherapy] were randomised 2:1 to atezolizumab 840 mg or placebo (days 1, 15), both with paclitaxel 90 mg/m 2 (days 1, 8, 15), every 28 days until disease progression or unacceptable toxicity. Stratification factors were tumour PD-L1 status, prior taxane, liver metastases and geographical region. The primary endpoint was investigator-assessed PFS, tested hierarchically first in the PD-L1-positive [immune cell expression 1%, VENTANA PD-L1 (SP142) assay] population, and then in the ITT population. OS was a secondary endpoint. Results: Of 651 randomised patients, 45% had PD-L1-positive aTNBC. At the primary PFS analysis, adding atezolizumab to paclitaxel did not improve investigator-assessed PFS in the PD-L1-positive population [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.60-1.12; P ¼ 0.20; median PFS 6.0 months with atezolizumabepaclitaxel versus 5.7 months with placeboepaclitaxel]. In the PD-L1-positive population, atezolizumabepaclitaxel was associated with more favourable unconfirmed best overall response rate (63% versus 55% with placeboepaclitaxel) and median duration of response (7.2 versus 5.5 months, respectively). Final OS results showed no difference between arms (HR 1.11, 95% CI 0.76-1.64; median 22.1 months with atezolizumabepaclitaxel versus 28.3 months with placeboe paclitaxel in the PD-L1-positive population). Results in the ITT population were consistent with the PD-L1-positive population. The safety profile was consistent with known effects of each study drug. Conclusion: Combining atezolizumab with paclitaxel did not improve PFS or OS versus paclitaxel alone. ClinicalTrials.gov: NCT03125902.
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