Several lines of evidence support targeting the androgen signaling pathway in breast cancer. Enzalutamide is a potent inhibitor of androgen receptor signaling. Preclinical data in estrogen-expressing breast cancer models demonstrated activity of enzalutamide monotherapy and enhanced activity when combined with various endocrine therapies (ET).
View Article and Find Full Text PDFPurpose: Preclinical evidence suggests that both docetaxel and enzalutamide target androgen receptor translocation and signaling. This phase Ib study assessed the safety, tolerability, and pharmacokinetics of docetaxel when administered with enzalutamide as first-line systemic chemotherapy in men with metastatic castration-resistant prostate cancer (mCRPC).
Experimental Methods: Docetaxel-naïve patients received 21-day cycles of docetaxel (75 mg/m(2)).
Purpose: Increased hepatocyte growth factor/MET signaling is associated with poor prognosis and acquired resistance to epidermal growth factor receptor (EGFR) -targeted drugs in patients with non-small-cell lung cancer (NSCLC). We investigated whether dual inhibition of MET/EGFR results in clinical benefit in patients with NSCLC.
Patients And Methods: Patients with recurrent NSCLC were randomly assigned at a ratio of one to one to receive onartuzumab plus erlotinib or placebo plus erlotinib; crossover was allowed at progression.
Purpose: Metastatic melanoma, a highly vascularized tumor with strong expression of vascular endothelial growth factor, has an overall poor prognosis. We conducted a placebo-controlled, double-blind phase II study of carboplatin plus paclitaxel with or without bevacizumab in patients with previously untreated metastatic melanoma.
Patients And Methods: Patients were randomly assigned in a two-to-one ratio to carboplatin (area under the curve, 5) plus paclitaxel (175 mg/m(2)) and bevacizumab (15 mg/kg; CPB) or placebo (CP) administered intravenously once every 3 weeks.
Despite the frequent detection of circulating tumor antigen-specific T cells, either spontaneously or following active immunization or adoptive transfer, immune-mediated cancer regression occurs only in the minority of patients. One theoretical rate-limiting step is whether effector T cells successfully migrate into metastatic tumor sites. Affymetrix gene expression profiling done on a series of metastatic melanoma biopsies revealed a major segregation of samples based on the presence or absence of T-cell-associated transcripts.
View Article and Find Full Text PDFBackground: Increasing evidence suggests that prostate cancer is visible to the immune system and is potentially responsive to immunotherapeutic interventions. Previous work has identified prostate-specific membrane antigen (PSMA) as a potential antigen for T-cell recognition, and specific PSMA epitopes presented by HLA-A2 have been described. One vaccination strategy that is being pursued in the clinic utilizes peptide-pulsed peripheral blood mononuclear cells (PBMC) + IL-12.
View Article and Find Full Text PDFT cell anergy has been correlated with defective signaling by the GTPase Ras, but causal and mechanistic data linking defective Ras activity with T cell anergy are lacking. Here we used adenoviral transduction to genetically manipulate nonproliferating T cells and show that active Ras restored interleukin 2 production and mitogen-activated protein kinase signaling in T cells that were made anergic in vitro or in vivo. Diacylglycerol kinases (DGKs), which negatively regulate Ras activity, were upregulated in anergic T cells, and a DGK inhibitor restored interleukin 2 production in anergic T cells.
View Article and Find Full Text PDFPurpose: Bryostatin-1 is a PKC modulator with direct anti-tumor activity and immunomodulatory properties. We combined different doses of Bryostatin-1 with IL-2 to determine effects on clinical response rate and T cell phenotype in patients with advanced kidney cancer.
Experimental Design: IL-2 naïve patients were given 11 x 10(6) IU subcutaneously of IL-2 on days 1-4, 8-11, and 15-18 of every 28-day cycle.
Although melanoma tumors usually express antigens that can be recognized by T cells, immune-mediated tumor rejection is rare. In many cases this is despite the presence of high frequencies of circulating tumor antigen-specific T cells, suggesting that tumor resistance downstream from T cell priming represents a critical barrier. Analyzing T cells directly from the melanoma tumor microenvironment, as well as the nature of the microenvironment itself, is central for understanding the key downstream mechanisms of tumor escape.
View Article and Find Full Text PDFPurpose: Vascular endothelial growth factor (VEGF) expression is prognostic in melanoma, and the activity of VEGF is mediated in part through the receptor tyrosine kinase Flk-1. A Phase II study of SU5416, a preferential inhibitor of Flk-1, was carried out in patients with metastatic melanoma to determine clinical response, tolerability, and changes in tumor vascular perfusion.
Experimental Design: Patients with documented progressive disease and =1 prior therapy were eligible.
Although increased circulating tumor antigen-specific CD8(+) T cells can be achieved by vaccination or adoptive transfer, tumor progression nonetheless often occurs through resistance to effector function. To develop a model for identifying mechanisms of resistance to antigen-specific CTLs, poorly immunogenic B16-F10 melanoma was transduced to express the K(b)-binding peptide SIYRYYGL as a green fluorescent protein fusion protein that should be recognized by high-affinity 2C TCR transgenic T cells. Although B16.
View Article and Find Full Text PDFThe adapter protein CrkL has been implicated in multiple signal transduction pathways in hematopoietic cells. In T lymphocytes, the recruitment of CrkL-C3G complexes has been correlated with hyporesponsiveness, implicating CrkL as a potential negative regulator. To test this hypothesis we examined T cell activation in CrkL-deficient mice.
View Article and Find Full Text PDFPurpose: Preclinical studies showed that immunization with peripheral blood mononuclear cells (PBMC) loaded with tumor antigen peptides plus interleukin-12 (IL-12) induced CD8+ T-cell responses and tumor rejection. We recently determined that recombinant human (rh) IL-12 at 30 to 100 ng/kg is effective as a vaccine adjuvant in patients. A phase II study of immunization with Melan-A peptide-pulsed PBMC + rhIL-12 was conducted in 20 patients with advanced melanoma.
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