Pegylated liposomal doxorubicin plus carboplatin in patients with metastatic breast cancer: a phase II study.

BACKGROUND: We determined the objective response rates produced by pegylated liposomal doxorubicin (PLD) plus carboplatin with/without trastuzumab (Herceptin). PATIENTS AND METHODS: Patients with measurable disease were stratified by taxane treatment history and human epidermal growth factor receptor-2 status. TREATMENT: PLD 30 mg/m(2) followed by carboplatin, day 1 of each 28-day cycle; human epidermal growth factor receptor-2 (HER2)-positive patients also received trastuzumab. RESULTS: Arm 1 received PLD plus carboplatin (N = 41 arm 1a, taxane naive; N = 42 arm 1b, taxane pretreated); Arm 2 patients received PLD plus carboplatin + Herceptin (N = 46). Overall response rates: 31%, 31%, and 56%, respectively. Median overall survival durations were not reached in arm 1a and were 13 and 33 months for arms 1b and 2. Median progression-free survival: 8, 5, 10 months, respectively. Grades 3-4 treatment-related toxic effects for arms 1a, 1b, 2, respectively, were neutropenia 22%, 31%, 35%; thrombocytopenia 34%, 26%, 17%; and fatigue 2%, 14%, 13%. CONCLUSIONS: PLD plus carboplatin has moderate antitumor activity and excellent tolerability. Herceptin and PLD plus carboplatin in HER2-positive patients have antitumor activity without significant cardiac toxicity. Toxicity results suggest that PLD can be combined with Herceptin with minimal cardiac toxicity.

Interferon-alpha induces the expression of the L-selectin homing receptor in human B lymphoid cells.

The L-selectin homing receptor expressed by lymphocytes mediates the initial attachment of these cells to high endothelial venules within peripheral lymph nodes. This adhesive interaction is required for the migration of B and T lymphocytes from the blood into peripheral lymph nodes. There is currently little information regarding the nature of the factors involved in the regulation of the synthesis and expression of L-selectin by lymphocytes. In this report, the immunomodulatory cytokine interferon-alpha (IFN-alpha) was shown to markedly upregulate the surface density of L-selectin in the established human B lymphoid Daudi cell line and in a subpopulation of tissue-derived human B lymphoid cells. Other cytokines such as IFN-gamma, tumor necrosis factor-alpha, interleukin (IL)-1 beta, IL-2, IL-4, IL-6, and low molecular weight B cell growth factor did not affect L-selectin surface expression in the model Daudi B cell line. Upregulation of L-selectin surface density in IFN-alpha-treated Daudi B cells correlated directly with an increase in L-selectin mRNA steady state levels and enhanced L-selectin-dependent binding to a carbohydrate-based ligand, phosphomonoester core polysaccharide. Regulation of L-selectin mRNA by IFN-alpha had characteristics similar to that of classical IFN-stimulated genes including rapid kinetics of induction, protein-synthesis-independent induction, and sensitivity to tyrosine-kinase inhibitors. IFN-alpha did not upregulate L-selectin mRNA levels or surface expression in an IFN-resistant Daudi subclone which exhibits a defect in the signal transduction pathway required for the transcriptional induction of IFN-stimulated genes. These data demonstrate a fundamental role for IFN-alpha in regulating L-selectin synthesis and expression in human B lymphoid cells and suggest a mechanism whereby this cytokine regulates the regional trafficking of B cells to peripheral lymph nodes.

IFN-alpha induces homotypic adhesion and Leu-13 expression in human B lymphoid cells.

IFN-alpha influences the recirculation and growth of normal and malignant B lymphocytes, although the mechanisms involved are not currently known. Lymphocyte recirculation is fundamentally dependent on cell-to-cell interactions that are mediated by cell surface adhesion molecules. In this report, we examined the relationship between the effect of IFN-alpha on cell-to-cell adhesion processes and induction of the Leu-13 cell surface protein in established human Daudi B lymphoid cell lines that are either sensitive or resistant to the antiproliferative activity of IFN-alpha. IFN-alpha directly triggered homotypic adhesion of IFN-sensitive Daudi B cells in a time- and dose-dependent manner. In contrast, IFN-alpha had no effect on the cell-to-cell adhesion of IFN-resistant Daudi B cells. The capacity of IFN-alpha to trigger homotypic aggregation correlated directly with the level of induction of the cell surface protein Leu-13 and could be potentiated by anti-Leu-13 mAb. Other cytokines also known to influence the proliferation, differentiation, or recirculation of B lymphocytes such as IFN-gamma, IL-2, IL-4, IL-6, TNF-alpha, and low molecular weight B cell growth factor did not induce either Leu-13 expression or homotypic aggregation of Daudi B cells. The adhesion pathway triggered by the IFN-inducible protein Leu-13 required metabolic energy and an intact cytoskeleton but was not dependent on: 1) new protein synthesis; 2) protein kinase C, protein kinase A, or tyrosine kinase activities; or 3) the function of known adhesion molecules including LFA-1, ICAM-1, CD44, or VLA-4. Taken together, these studies demonstrate a fundamental role for IFN-alpha and the IFN-inducible protein Leu-13 in regulating a novel homotypic adhesion pathway in B lymphocytes, and provide insight into the possible mechanisms by which IFN-alpha regulates biologic processes including recirculation.