Pooled analyses of eribulin in metastatic breast cancer patients with at least one prior chemotherapy.

BACKGROUND: Based on data from two multicenter, phase III clinical trials (Studies 301 and 305), eribulin (a microtubule dynamics inhibitor) is indicated in the European Union (EU) for patients with locally advanced or metastatic breast cancer (MBC) after ≥1 prior chemotherapy for advanced disease, including an anthracycline and a taxane in either the adjuvant or metastatic setting. Data from Studies 305 and 301 were pooled to investigate the efficacy of eribulin in various subgroups of patients who matched the EU label, including those with human epidermal growth factor receptor 2 (HER2)-negative and triple-negative disease. PATIENTS AND METHODS: In Study 305 (NCT00388726), patients were randomized 2:1 to eribulin mesylate 1.4 mg/m(2) (equivalent to eribulin 1.23 mg/m(2) [expressed as free base]) intravenously on days 1 and 8 every 21 days] or treatment of physician's choice after 2-5 prior chemotherapies (≥2 for advanced disease), including an anthracycline and a taxane (in early/advanced setting). In Study 301 (NCT00337103), patients were randomized 1:1 to eribulin (as above) or capecitabine (1.25 g/m(2) orally twice daily on days 1-14 every 21 days) following ≤3 prior chemotherapies (≤2 for advanced disease), including an anthracycline and a taxane. Efficacy end points were investigated in the intent-to-treat population and subgroups, pooled as discussed above. RESULTS: Overall, 1644 patients were included (eribulin: 946; control: 698); baseline characteristics were well matched. Overall survival was significantly longer with eribulin versus control (P < 0.01), as were progression-free survival and clinical benefit rate (both P < 0.05). Significant survival benefits with eribulin versus control were observed in a wide range of patient subgroups, including HER2-negative or triple-negative disease (all P < 0.05). CONCLUSION: Our findings underline the survival benefit achieved by eribulin used according to EU label in the overall MBC population and in various subgroups of interest, including patients with HER2-negative and triple-negative disease.

[Endocrine therapy resistance in metastatic breast cancer: mechanisms and clinical implications]. / Résistance à l'endocrinothérapie dans le cancer du sein: mécanismes et implications cliniques.

Endocrine therapy remains a mainstay in the treatment of hormone-sensitive metastatic breast cancer. Nevertheless, acquired resistance to endocrine therapy is an important clinical problem. Understanding the mechanisms of resistance is fundamental in order to develop new therapeutic strategies such as mTOR inhibition through everolimus. Its efficacy in association with endocrine therapy has been shown in two randomized trials. However, the addition of everolimus to endocrine therapy is accompanied by a significant increase in potentially severe side effects. Identifying and adequately addressing these side effects is crucial to decrease toxicity of these new therapies.

Inactivation of Notch 1 in immature thymocytes does not perturb CD4 or CD8T cell development.

Notch proteins influence cell-fate decisions in many developing systems. Several gain-of-function studies have suggested a critical role for Notch 1 signaling in CD4-CD8 lineage commitment, maturation and survival in the thymus. However, we show here that tissue-specific inactivation of the gene encoding Notch 1 in immature (CD25+CD44-)T cell precursors does not affect subsequent thymocyte development. Neither steady-state numbers nor the rate of production of CD4+ and CD8+ mature thymocytes is perturbed in the absence of Notch 1. In addition, Notch 1-deficient thymocytes are normally sensitive to spontaneous or glucocorticoid-induced apoptosis. In contrast to earlier reports, these data formally exclude an essential role for Notch 1 in CD4-CD8 lineage commitment, maturation or survival.