Peptide vaccination in Montanide adjuvant induces and GM-CSF increases CXCR3 and cutaneous lymphocyte antigen expression by tumor antigen-specific CD8 T cells.

T cell infiltration of melanoma is associated with enhanced clinical efficacy and is a desirable endpoint of immunotherapeutic vaccination. Infiltration is regulated, in part, by chemokine receptors and selectin ligands on the surface of tumor-specific lymphocytes. Therefore, we investigated the expression of two homing molecules--CXCR3 and CLA - on vaccine-induced CD8 T cells, in the context of a clinical trial of a melanoma-specific peptide vaccine. Both CXCR3 and CLA have been associated with T cell infiltration of melanoma. We demonstrate that a single subcutaneous/intradermal administration of peptide vaccine in Montanide adjuvant induces tumor-specific CD8 T cells that are predominantly positive for CXCR3, with a subpopulation of CXCR3(+)CLA(+) cells. Addition of GM-CSF significantly enhances CXCR3 expression and increases the proportion of CLA-expressing cells. Concurrent with CXCR3 and CLA expression, vaccine-induced CD8 cells express high levels of Tbet, IFN-γ, and IL-12Rß1. Collectively, these studies demonstrate that peptide vaccination in adjuvant induces CD8 T cells with a phenotype that may support infiltration of melanoma.

Differential expression and tumor necrosis factor-mediated regulation of TNFRSF11b/osteoprotegerin production by human melanomas.

Tumors escape host immune responses, in part, through the release of immunomodulatory factors and decoy receptors into their microenvironment. Several cancers express surface-bound and soluble members of the tumor necrosis factor (TNF) receptor superfamily, including TNFRSF11b/osteoprotegerin (OPG). In its physiologic role, OPG regulates bone remodeling through competition for osteoclast-activating cytokines and protects newly forming bone from T cell-mediated apoptosis. In multiple tumor types, OPG production is associated with an aggressive phenotype and increased metastasis to bone, but no study has examined OPG production in human metastatic melanoma. We demonstrate that a significant proportion of human metastatic melanomas constitutively produces OPG through a mechanism governed by membrane-bound TNF-α signaling through TNF receptor 1 (TNFR1). These observations both define a specific mechanism that regulates melanoma production of OPG and establish a new molecular target for the therapeutic regulation of OPG.

Data mining and clinical data repositories: Insights from a 667,000 patient data set.

Clinical repositories containing large amounts of biological, clinical, and administrative data are increasingly becoming available as health care systems integrate patient information for research and utilization objectives. To investigate the potential value of searching these databases for novel insights, we applied a new data mining approach, HealthMiner, to a large cohort of 667,000 inpatient and outpatient digital records from an academic medical system. HealthMiner approaches knowledge discovery using three unsupervised methods: CliniMiner, Predictive Analysis, and Pattern Discovery. The initial results from this study suggest that these approaches have the potential to expand research capabilities through identification of potentially novel clinical disease associations.

CXC chemokine receptor 3 expression by activated CD8+ T cells is associated with survival in melanoma patients with stage III disease.

Despite the presence of tumor Ag-specific CD8(+) T cells in the peripheral blood, metastatic melanoma often evades immune-mediated destruction. Even after therapeutic efforts to expand Ag-specific T-cell populations, the correlation between magnitude of response and clinical efficacy has been weak. Because the migratory phenotype of tumor Ag-specific effector T cells may determine their ability for tumor control, we hypothesized that the expression of CC or CXC chemokine receptor (CCR) molecules on activated CD8(+) T cells may define phenotypes associated with more effective control of melanoma progression and prolonged survival. In a retrospective evaluation of patient isolates, CCR expression was determined for activated CD8(+) T cells derived from the peripheral blood or tumor-involved lymph nodes of 52 patients with stage III or IV metastatic melanoma. In patients with stage III disease, expression of CXCR3 by CD8(+)CD45RO(+) cells was significantly associated with enhanced survival. This was a stage-specific effect, because it was not observed in patients with stage IV disease. In addition, CCR4 and CXCR3 were highly coexpressed and associated with enhanced survival in stage III patients; however, CXCR3 seems to be the dominant receptor associated with clinical outcome. These findings support the hypothesis that the host immune system affects cancer progression and control, and that measures of CCR status of circulating lymphocytes may have prognostic value.

Amino acid variation in the 10 kDa Oryza prolamin seed storage protein.

The deduced amino acid variability for the 10 kDa prolamin was determined for 16 Oryza species, both cultivated (rice) and wild. Prolamin, a seed storage protein and site of nitrogen and sulfur accumulation, is sequestered in the subaleurone layer of the starchy endosperm for use during seedling germination. The 10 kDa prolamin amino acid distribution for the cultivated species (O. sativa and O. glaberrima) was determined and compared to those of wild and, hitherto unknown, noncultivated Oryza species. Four wild species (O. granulata, O. australiensis, O. brachyantha, and O. meyeriana) exhibited the greatest residue heterogeneity in both the signal and mature peptide regions. A breakdown of the essential amino acid variance among three Central/South American and one African endemic wild species is also presented and compared with those of rice.