Aurora kinase inhibition sensitizes melanoma cells to T-cell-mediated cytotoxicity.

Although immunotherapy has achieved impressive durable clinical responses, many cancers respond only temporarily or not at all to immunotherapy. To find novel, targetable mechanisms of resistance to immunotherapy, patient-derived melanoma cell lines were transduced with 576 open reading frames, or exposed to arrayed libraries of 850 bioactive compounds, prior to co-culture with autologous tumor-infiltrating lymphocytes (TILs). The synergy between the targets and TILs to induce apoptosis, and the mechanisms of inhibiting resistance to TILs were interrogated.

Development of ion pairing LC-MS/MS method for itaconate and cis-aconitate in cell extract and cell media.

Accumulation of Immune Responsive Gene 1(IRG1) in macrophage induced by lipopolysaccharide (LPS) and interferon gamma (IFN-γ) leads to production of itaconate by decarboxylation of cis-aconitate. The biology associated with IRG1 and itaconate is not fully understood. A rapid and sensitive method for measurement of itaconate will benefit the study of IRG1 biology.

Increased Tumor Glycolysis Characterizes Immune Resistance to Adoptive T Cell Therapy.

Adoptive T cell therapy (ACT) produces durable responses in some cancer patients; however, most tumors are refractory to ACT and the molecular mechanisms underlying resistance are unclear. Using two independent approaches, we identified tumor glycolysis as a pathway associated with immune resistance in melanoma. Glycolysis-related genes were upregulated in melanoma and lung cancer patient samples poorly infiltrated by T cells.

The RNA-binding Protein MEX3B Mediates Resistance to Cancer Immunotherapy by Downregulating HLA-A Expression.

Cancer immunotherapy has shown promising clinical outcomes in many patients. However, some patients still fail to respond, and new strategies are needed to overcome resistance. The purpose of this study was to identify novel genes and understand the mechanisms that confer resistance to cancer immunotherapy.

The Effect of Topoisomerase I Inhibitors on the Efficacy of T-Cell-Based Cancer Immunotherapy.

Background: Immunotherapy has increasingly become a staple in cancer treatment. However, substantial limitations in the durability of response highlight the need for more rational therapeutic combinations. The aim of this study is to investigate how to make tumor cells more sensitive to T-cell-based cancer immunotherapy.

HSP90 inhibition enhances cancer immunotherapy by upregulating interferon response genes.

T-cell-based immunotherapies are promising treatments for cancer patients. Although durable responses can be achieved in some patients, many patients fail to respond to these therapies, underscoring the need for improvement with combination therapies. From a screen of 850 bioactive compounds, we identify HSP90 inhibitors as candidates for combination with immunotherapy.

High-Throughput Screening of Myxoid Liposarcoma Cell Lines: Survivin Is Essential for Tumor Growth.

Myxoid liposarcoma (MLS) is a soft tissue sarcoma characterized by a recurrent t(12;16) translocation. Although tumors are initially radio- and chemosensitive, the management of inoperable or metastatic MLS can be challenging. Therefore, our aim was to identify novel targets for systemic therapy.

Loss of PTEN Promotes Resistance to T Cell-Mediated Immunotherapy.

Unlabelled: T cell-mediated immunotherapies are promising cancer treatments. However, most patients still fail to respond to these therapies. The molecular determinants of immune resistance are poorly understood.

Analysis of the intratumoral adaptive immune response in well differentiated and dedifferentiated retroperitoneal liposarcoma.

Treatment options are limited in well differentiated (WD) and dedifferentiated (DD) retroperitoneal liposarcoma. We sought to study the intratumoral adaptive immune response and explore the potential feasibility of immunotherapy in this disease. Tumor-infiltrating lymphocytes (TILs) were isolated from fresh surgical specimens and analyzed by flow cytometry for surface marker expression.

Activation and propagation of tumor-infiltrating lymphocytes on clinical-grade designer artificial antigen-presenting cells for adoptive immunotherapy of melanoma.

Purpose: Adoptive cell therapy with autologous tumor-infiltrating lymphocytes (TIL) is a therapy for metastatic melanoma with response rates of up to 50%. However, the generation of the TIL transfer product is challenging, requiring pooled allogeneic normal donor peripheral blood mononuclear cells (PBMC) used in vitro as "feeders" to support a rapid-expansion protocol. Here, we optimized a platform to propagate TIL to a clinical scale using K562 cells genetically modified to express costimulatory molecules such as CD86, CD137-ligand, and membrane-bound IL-15 to function as artificial antigen-presenting cells (aAPC) as an alternative to using PBMC feeders.

DNA Ligase IV regulates XRCC4 nuclear localization.

DNA Ligase IV, along with its interacting partner XRCC4, are essential for repairing DNA double strand breaks by non-homologous end joining (NHEJ). Together, they complete the final ligation step resolving the DNA break. Ligase IV is regulated by XRCC4 and XLF.

Structural basis of DNA ligase IV-Artemis interaction in nonhomologous end-joining.

DNA ligase IV (LigIV) and Artemis are central components of the nonhomologous end-joining (NHEJ) machinery that is required for V(D)J recombination and the maintenance of genomic integrity in mammalian cells. We report here crystal structures of the LigIV DNA binding domain (DBD) in both its apo form and in complex with a peptide derived from the Artemis C-terminal region. We show that LigIV interacts with Artemis through an extended hydrophobic surface.

Role of non-homologous end joining in V(D)J recombination.

The pathway of V(D)J recombination was discovered almost three decades ago. Yet it continues to baffle scientists because of its inherent complexity and the multiple layers of regulation that are required to efficiently generate a diverse repertoire of T and B cells. The non-homologous end-joining (NHEJ) DNA repair pathway is an integral part of the V(D)J reaction, and its numerous players perform critical functions in generating this vast diversity, while ensuring genomic stability.

Artemis C-terminal region facilitates V(D)J recombination through its interactions with DNA Ligase IV and DNA-PKcs.

Artemis is an endonuclease that opens coding hairpin ends during V(D)J recombination and has critical roles in postirradiation cell survival. A direct role for the C-terminal region of Artemis in V(D)J recombination has not been defined, despite the presence of immunodeficiency and lymphoma development in patients with deletions in this region. Here, we report that the Artemis C-terminal region directly interacts with the DNA-binding domain of Ligase IV, a DNA Ligase which plays essential roles in DNA repair and V(D)J recombination.

Modulation of cell cycle progression by CTLA4-CD80/CD86 interactions on CD4+ T cells depends on strength of the CD3 signal: critical role for IL-2.

Cytotoxic T-lymphocyte antigen 4 (CTLA4) is a well-studied T cell costimulatory receptor that is known to inhibit T cell activation. In this study, the relationship between strength of the first signal and costimulatory interactions on primary mouse CD4(+) T cells was investigated. CTLA4-CD80/CD86 interactions differentially modulate T cell cycling based on the mode of CD3 signal: Activation with plate-bound (pb) anti-CD3 generates a strong signal compared with a weak signal with soluble (sol) anti-CD3, resulting in approximately sevenfold higher amounts of interleukin (IL)-2 and an increase in cell cycling.

IFN-gamma bioassay: development of a sensitive method by measuring nitric oxide production by peritoneal exudate cells from C57BL/6 mice.

Interferon-gamma (IFN-gamma) is an important immunomodulatory and pleiotropic cytokine produced, primarily, by activated T lymphocytes and natural killer (NK) cells. We have devised a nitric oxide (NO)-based bioassay for mouse IFN-gamma using resident peritoneal exudate cells (PECs) from C57BL/6 mice. Comparison with three existing bioassays demonstrated that this assay was very sensitive and detected IFN-gamma in the linear range of approximately 0.