CD25 blockade depletes and selectively reprograms regulatory T cells in concert with immunotherapy in cancer patients.

Regulatory T cells (T(regs)) are key mediators of immune tolerance and feature prominently in cancer. Depletion of CD25(+) FoxP3(+) T(regs) in vivo may promote T cell cancer immunosurveillance, but no strategy to do so in humans while preserving immunity and preventing autoimmunity has been validated. We evaluated the Food and Drug Administration-approved CD25-blocking monoclonal antibody daclizumab with regard to human T(reg) survival and function.

Frequent genetic abnormalities of the PI3K/AKT pathway in primary ovarian cancer predict patient outcome.

Identification and characterization of underlying genetic aberrations could facilitate diagnosis and treatment of ovarian cancer. Copy number analysis using array Comparative Genomic Hybridization (aCGH) on 93 primary ovarian tumors identified PI3K/AKT pathway as the most frequently altered cancer related pathway. Furthermore, survival analyses to correlate gene copy number and mutation data with patient outcome showed that copy number gains of PIK3CA, PIK3CB, and PIK3R4 in these tumors were associated with decreased survival.

Functional unresponsiveness and replicative senescence of myeloid leukemia antigen-specific CD8+ T cells after allogeneic stem cell transplantation.

Purpose: The therapeutic effect of allogeneic hematopoietic stem cell transplantation (HSCT) for patients with myeloid malignancies has been attributed in part to a graft-versus-leukemia effect that is dependent on donor T lymphocytes. CD8(+) T-cell responses to MHC class I-restricted tumor epitopes, not just allogeneic antigens, may help mediate antileukemia effects after HSCT, but the specificity and function of such cells are not completely understood.

Experimental Design: We examined the diversity, phenotype, and functional potential of leukemia-associated antigen-specific CD8(+) T cells in patients with myeloid leukemia following allogeneic HSCT.

Collapse of the CD27+ B-cell compartment associated with systemic plasmacytosis in patients with advanced melanoma and other cancers.

Purpose: Disturbed peripheral blood B-cell homeostasis complicates certain infections and autoimmune diseases, such as HIV and systemic lupus erythematosus, but has not been reported in cancer. This study aimed to investigate whether B-cell physiology was altered in the presence of melanoma and other cancers.

Experimental Design: Flow cytometry was used to identify phenotypic differences in B cells from patients with melanoma and normal donors.