Project description:Clinical approaches to treat advanced melanoma include immune therapies, whose benefits depend on tumor-reactive T-cells to infiltrate metastases. However, most tumors lack significant immune infiltration prior to therapy, and some immune therapies are hindered by a persistent lack of immune cell infiltration. CXCL10 has been implicated as a critical chemokine supporting T-cell migration into tumors; thus agents that induce CXCL10 in tumors may improve patient responses to systemic immune therapy. We find that melanoma cells treated with TLR2/6 agonists (MALP-2 or FSL-1) and interferon-gamma (IFNgamma) upregulate CXCL10 production, when compared to IFNgamma treatment alone or no treatment. Gene profiling of melanoma cells lines treated with TLR2/6 agonists and IFNgamma demonstrate that a selective profile of genes are induced which may be favorable for promoting immune cell infiltration of tumors. TLR2 and TLR6 are widely expressed on human melanoma cells, and treatment of melanoma cells with TLR2/6 agonists and IFNgamma does not hinder melanoma cell apoptosis or promote proliferation. Furthermore, melanoma cells from surgically resected patient tumors upregulate CXCL10 production after treatment with TLR2/6 agonists and IFNgamma when compared to treatment with either agent alone. Collectively, these data identify TLR2/6 agonists and IFNgamma as a novel target for promoting CXCL10 production directly from melanoma cells. Samples from four human melanoma cell lines, VMM1 (n=6), DM13 (n=6), DM93 (n=6) and VMM39 (n=6), were treated with media alone, MALP-2 (TLR2/6 agonist), FSL-1 (TLR2/6 agonist), IFNgamma alone, MALP-2 and IFNgamma, or FSL-1 and IFNgamma.
Project description:Clinical approaches to treat advanced melanoma include immune therapies, whose benefits depend on tumor-reactive T-cells to infiltrate metastases. However, most tumors lack significant immune infiltration prior to therapy, and some immune therapies are hindered by a persistent lack of immune cell infiltration. CXCL10 has been implicated as a critical chemokine supporting T-cell migration into tumors; thus agents that induce CXCL10 in tumors may improve patient responses to systemic immune therapy. We find that melanoma cells treated with TLR2/6 agonists (MALP-2 or FSL-1) and interferon-gamma (IFNgamma) upregulate CXCL10 production, when compared to IFNgamma treatment alone or no treatment. Gene profiling of melanoma cells lines treated with TLR2/6 agonists and IFNgamma demonstrate that a selective profile of genes are induced which may be favorable for promoting immune cell infiltration of tumors. TLR2 and TLR6 are widely expressed on human melanoma cells, and treatment of melanoma cells with TLR2/6 agonists and IFNgamma does not hinder melanoma cell apoptosis or promote proliferation. Furthermore, melanoma cells from surgically resected patient tumors upregulate CXCL10 production after treatment with TLR2/6 agonists and IFNgamma when compared to treatment with either agent alone. Collectively, these data identify TLR2/6 agonists and IFNgamma as a novel target for promoting CXCL10 production directly from melanoma cells.
Project description:Melanoma is the most lethal form of skin cancer. Clinical efforts to combat melanoma include immune therapies whose benefit depends on antitumor T-cells, to target and to clear melanoma. However, most tumors lack significant immune infiltration prior to therapy, and some immune therapies are hindered by a persistent lack of immune-cell infiltration. Chemokines can promote T-cell migration into tumors; therefore, agents that induce T-cell attracting chemokines in the tumor microenvironment could potentially improve the clinical activity of current immune therapies for melanoma. CXCL10 has been implicated as a critical chemokine supporting T-cell infiltration into the tumor microenvironment. Here we report that combination treatment of human melanoma cell lines with Toll-like receptor (TLR) 2/6 agonists MALP-2 or FSL-1 +IFNlambda synergize to induce production of immune-cell attracting chemokines CCL3 and CXCL10 by melanoma cells. We find that TLR2 and TLR6 are widely expressed on human melanoma cells, and that stimulation of fresh patient melanoma specimens with TLR2/6 agonists+IFNlambda induces CXCL10 production from melanoma cells, endothelial and immune-cells. Furthermore, ex vivo migration assays demonstrate that stimulation of melanoma cells with TLR2/6 agonists+IFNlambda increases CD4+ and CD8+ T-cell migration toward melanoma. Collectively, these data identify a novel synergy of TLR2/6 agonists+IFNlambda for inducing CXCL10 production by melanoma cells and suggest that intralesional administration of TLR2/6 agonists+IFNlambda may improve immune signatures in melanoma metastases and have value in combination with other immune therapies, by supporting better T-cell migration to melanoma.
Project description:Introduction: Optimal approaches to induce T-cell infiltration of tumors are not known. Chemokines CXCL9, CXCL10, and CXCL11 support effector T-cell recruitment, and may be induced by IFNgamma. This study tests the hypothesis that intratumoral administration of IFNgamma will induce CXCL9-11, and will induce T-cell recruitment and anti-tumor immune signatures in melanoma metastases. Patients and Methods: Nine eligible patients were immunized with a vaccine comprised of 12 class I MHC-restricted melanoma peptides (12MP) and received IFNgamma intratumorally. Effects on the tumor microenvironment (TME) were evaluated in sequential tumor biopsies. Adverse events (AE; CTCAE v4) were recorded. T-cell responses to vaccination were assessed in peripheral blood (PBMC) by IFNgamma ELIspot assay. Tumor biopsies were evaluated for immune cell infiltration, chemokine protein expression and gene expression. Results: Vaccination and intratumoral administration of IFNgamma were well tolerated. Circulating T-cell responses to vaccine were detected in 6 of 9 patients. IFNgamma increased production of chemokines CXCL10, CXCL11, and CCL5 in patient tumors. Neither vaccination alone nor the addition of IFNgamma promoted immune cell infiltration or induced anti-tumor immune gene signatures. Conclusion: The cancer vaccine did not significantly increase T-cell infiltration of tumors. This study provides intriguing findings highlighting some of the limitations of intratumoral IFNgamma treatment. Although IFNgamma is pivotal in anti-tumor immunity, single intratumoral injection may induce secondary immune regulation that paradoxically limits immune infiltration and effector functions. Therefore, alternate dosing strategies or additional combinatorial treatments may be needed to optimally promote trafficking and retention of T-cells in tumor, which merit further study.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
Project description:As the evolution of miRNA genes has been found to be one of the important factors in formation of the modern type of man, we performed a comparative analysis of the evolution of miRNA genes in two archaic hominines, Homo sapiens neanderthalensis and Homo sapiens denisova, and elucidated the expression of their target mRNAs in bain.A comparative analysis of the genomes of primates, including species in the genus Homo, identified a group of miRNA genes having fixed substitutions with important implications for the evolution of Homo sapiens neanderthalensis and Homo sapiens denisova. The mRNAs targeted by miRNAs with mutations specific for Homo sapiens denisova exhibited enhanced expression during postnatal brain development in modern humans. By contrast, the expression of mRNAs targeted by miRNAs bearing variations specific for Homo sapiens neanderthalensis was shown to be enhanced in prenatal brain development.Our results highlight the importance of changes in miRNA gene sequences in the course of Homo sapiens denisova and Homo sapiens neanderthalensis evolution. The genetic alterations of miRNAs regulating the spatiotemporal expression of multiple genes in the prenatal and postnatal brain may contribute to the progressive evolution of brain function, which is consistent with the observations of fine technical and typological properties of tools and decorative items reported from archaeological Denisovan sites. The data also suggest that differential spatial-temporal regulation of gene products promoted by the subspecies-specific mutations in the miRNA genes might have occurred in the brains of Homo sapiens denisova and Homo sapiens neanderthalensis, potentially contributing to the cultural differences between these two archaic hominines.
Project description:PurposeWe investigated the evidence of recent positive selection in the human phototransduction system at single nucleotide polymorphism (SNP) and gene level.MethodsSNP genotyping data from the International HapMap Project for European, Eastern Asian, and African populations was used to discover differences in haplotype length and allele frequency between these populations. Numeric selection metrics were computed for each SNP and aggregated into gene-level metrics to measure evidence of recent positive selection. The level of recent positive selection in phototransduction genes was evaluated and compared to a set of genes shown previously to be under recent selection, and a set of highly conserved genes as positive and negative controls, respectively.ResultsSix of 20 phototransduction genes evaluated had gene-level selection metrics above the 90th percentile: RGS9, GNB1, RHO, PDE6G, GNAT1, and SLC24A1. The selection signal across these genes was found to be of similar magnitude to the positive control genes and much greater than the negative control genes.ConclusionsThere is evidence for selective pressure in the genes involved in retinal phototransduction, and traces of this selective pressure can be demonstrated using SNP-level and gene-level metrics of allelic variation. We hypothesize that the selective pressure on these genes was related to their role in low light vision and retinal adaptation to ambient light changes. Uncovering the underlying genetics of evolutionary adaptations in phototransduction not only allows greater understanding of vision and visual diseases, but also the development of patient-specific diagnostic and intervention strategies.
Project description:Cortical thickness has been investigated since the beginning of the 20th century, but we do not know how similar the cortical thickness profiles among humans are. In this study, the local similarity of cortical thickness profiles was investigated using sliding window methods. Here, we show that approximately 5% of the cortical thickness profiles are similarly expressed among humans while 45% of the cortical thickness profiles show a high level of heterogeneity. Therefore, heterogeneity is the rule, not the exception. Cortical thickness profiles of somatosensory homunculi and the anterior insula are consistent among humans, while the cortical thickness profiles of the motor homunculus are more variable. Cortical thickness profiles of homunculi that code for muscle position and skin stimulation are highly similar among humans despite large differences in sex, education, and age. This finding suggests that the structure of these cortices remains well preserved over a lifetime. Our observations possibly relativize opinions on cortical plasticity.