Project description:To identify critical tumor-secreting factors that may contribute to immunotherapy efficacy against HCC, we subjected tumor samples from 10 HCC patients to whole-transcriptome sequencing, and categorized the patients into two groups according to clinical response to nivolumab. We then performed gene expression profiling analysis using data obtained from RNA-seq of Nivolumab reponders and non-reponsers.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
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:Recent evidence suggests that immune checkpoint blockade (ICB) has some activity in metastatic dedifferentiated liposarcoma (DDLPS) and undifferentiated pleomorphic sarcoma (UPS). We conducted a randomized, non-comparative phase 2 trial (NCT03307616) of nivolumab or nivolumab/ipilimumab in patients with resectable retroperitoneal DDLPS (n=17) and extremity/truncal UPS (n=10), with UPS patients receiving concurrent radiation therapy. The primary endpoint of pathologic response as assessed by percent hyalinization was observed to be a median of 8.8% in DDLPS patients and 89% in UPS patients and similar in nivolumab and ipilimumab/nivolumab arms in both cohorts . Higher intratumoral densities of T-regulatory cells were associated with absence of pathologic response (hyalinization<30%). Tumor infiltration by B-cells was associated with higher densities of T-regulatory cells before treatment; this association was lost upon ICB treatment. Our data demonstrate that neoadjuvant ICB with concurrent radiation may have significant efficacy in UPS and is associated complex immune changes in the tumor microenvironment in DDLPS and UPS.
