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  • Juhl Kang posted an update 2 weeks, 1 day ago

    Marinacci anastomosis or the reverse Martin-Gruber anastomosis is a rare anomalous intercommunication from the ulnar nerve to the median nerve in the forearm. A young lady was involved in a road traffic accident that resulted in the fracture of both forearm bones for which she was treated surgically. A nerve conduction study was performed later on, which incidentally demonstrated findings of this communication. Knowledge of this anastomosis can help prevent misdiagnosis of clinical findings and misinterpretation of electrophysiological studies and help mitigate iatrogenic injury during surgical procedures.Interleukin-1 (IL-1) is an inflammatory cytokine associated with tumor invasiveness and metastasis. We recently found that baseline IL-1 in melanomas promoted resistance to immunotherapy by creating an immunosuppressive tumor microenvironment and that IL-1 produced in response to CD40 agonist also induced resistance to therapy. Here, we discuss how naturally occurring and immunotherapy-induced IL-1 in tumors causes immune suppression and resistance to immunotherapy, and we discuss targeting the IL-1 pathway to enhance the efficacy of immunotherapy.Immune checkpoint inhibitors (ICIs) have improved the survival of patients with non-small cell lung cancer (NSCLC) by reinvigorating tumor-specific T cell responses. However, the specificity of such T cells and the human leukocyte antigen (HLA)-associated epitopes recognized, remain elusive. In this study, we identified NSCLC T cell epitopes of recently described NSCLC-associated antigens, termed keratinocyte differentiation antigens. Epitopes of these antigens were presented by HLA-A 0301 and HLA-C 0401 and were associated with responses to ICI therapy. Patients with CD8+ T cell responses to these epitopes had improved overall and progression-free survival. T cells specific for such epitopes could eliminate HLA class I-matched NSCLC cells ex vivo and were enriched in patient lung tumors. The identification of novel lung cancer HLA-associated epitopes that correlate with improved ICI-dependent treatment outcomes suggests that keratinocyte-specific proteins are important tumor-associated antigens in NSCLC. These findings improve our understanding of the mechanisms of ICI therapy and may help support the development of vaccination strategies to improve ICI-based treatment of these tumors.Bladder cancer (BC) and melanoma are amenable to immune checkpoint blockade (ICB) therapy, yet most patients with advanced/metastatic disease do not respond. CD122-targeted interleukin (IL)-2 can improve ICB efficacy, but mechanisms are unclear. We tested αPD-L1 and CD122-directed immunotherapy with IL-2/αIL-2 complexes (IL-2c) in primary and metastatic bladder and melanoma tumors. IL-2c treatment of orthotopic MB49 and MBT-2 BC generated NK cell antitumor immunity through enhanced activation, reduced exhaustion, and promotion of a mature, effector NK cell phenotype. By comparison, subcutaneous B16-F10 melanoma, which is IL-2c sensitive, requires CD8+ T and not NK cells, yet we found αPD-L1 efficacy requires both CD8+ T and NK cells. We then explored αPD-L1 and IL-2c mechanisms at distinct metastatic sites and found intraperitoneal B16-F10 metastases were sensitive to αPD-L1 and IL-2c, with IL-2c but not αPD-L1, increasing CD122+ mature NK cell function, confirming conserved IL-2c effects in distinct cancer types and anatomic compartments. αPD-L1 failed to control tumor growth and prolong survival in B16-F10 lung metastases, yet IL-2c treated B16-F10 lung metastases effectively even in T cell and adaptive immunity deficient mice, which was abrogated by NK cell depletion in wild-type mice. Flow cytometric analyses of NK cells in B16-F10 lung metastases suggest that IL-2c directly boosts NK cell activation and effector function. Thus, αPD-L1 and IL-2c mediate nonredundant, immune microenvironment-specific treatment mechanisms involving CD8+ T and NK cells in primary and metastatic BC and melanoma. Mechanistic differences suggest effective treatment combinations including in other tumors or sites, warranting further studies.High mobility group B1 (HMGB1) is a protein that is released from dying cancer cells in the context of immunogenic cell death (ICD). A recent study performed on patients with head and neck squamous cell carcinomas (HNSCC) reports that a chemoradiotherapy-induced increase in circulating HMGB1 levels predicts favorable outcome, echoing prior studies on neoadjuvant treatment of breast and rectal cancer in which the dynamics of HMGB1 plasma levels also have prognostic value. Hence, a therapy-induced rise in HMGB1 may be interpreted as a clinical sign of ICD and therapeutic response.Cancer cells exploit CD47 overexpression to inhibit phagocytic elimination and neoantigen processing via the myeloid CD47-SIRPα axis and thereby indirectly evade adaptive T cell immunity. Here, we report on a hitherto unrecognized direct immunoinhibitory feature of cancer cell-expressed CD47. We uncovered that in response to IFNγ released during cognate T cell immune attack, cancer cells dynamically enhance CD47 cell surface expression, which coincides with acquiring adaptive immune resistance toward pro-apoptotic effector T cell mechanisms. Indeed, CRISPR/Cas9-mediated CD47-knockout rendered cancer cells more sensitive to cognate T cell immune attack. Subsequently, we developed a cancer-directed strategy to selectively overcome CD47-mediated adaptive immune resistance using bispecific antibody (bsAb) CD47xEGFR-IgG2s that was engineered to induce rapid and prolonged cancer cell surface displacement of CD47 by internalization. Treatment of CD47pos cancer cells with bsAb CD47xEGFR-IgG2s potently enhanced susceptibility to cognate CD8pos T cells. Targeting CD47-mediated adaptive immune resistance may open up new avenues in cancer immunotherapy.Kynurenine (Kyn) is a key inducer of an immunosuppressive tumor microenvironment (TME). Although indoleamine 2,3-dioxygenase (IDO)-selective inhibitors have been developed to suppress the Kyn pathway, the results were not satisfactory due to the presence of various opposing mechanisms. Here, we employed an orally administered novel Kyn pathway regulator to overcome the limitation of anti-tumor immune response. We identified a novel core structure that inhibited both IDO and TDO. An orally available lead compound, STB-C017 (designated hereafter as STB), effectively inhibited the enzymatic and cellular activity of IDO and TDO in vitro. Moreover, it potently suppressed Kyn levels in both the plasma and tumor in vivo. STB monotherapy increased the infiltration of CD8+ T cells into TME. In addition, STB reprogrammed the TME with widespread changes in immune-mediated gene signatures. Notably, STB-based combination immunotherapy elicited the most potent anti-tumor efficacy through concurrent treatment with immune checkpoint inhibitors, leading to complete tumor regression and long-term overall survival. Our study demonstrated that a novel Kyn pathway regulator derived using deep learning technology can activate T cell immunity and potentiate immune checkpoint blockade by overcoming an immunosuppressive TME.Numerous studies have found that chronic stress could promote tumor progression and this may be related to inhibtion of immune system. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of cells with immunosuppressive activity. MDSCs may represent a key link between chronic stress and tumor progression. However, the role of stress-induced MDSCs in breast cancer progression is unclear. The present study showed that pre-exposure of chronic stress could lead to MDSCs elevation and facilitated breast cancer metastasis in tumor-bearing mice. Adoptive transfer of MDSCs could significantly increase lung metastatic foci. In contrast, lung metastasis could be alleviated by depleting endogenous MDSCs with Gr-1 antibody. The concentration of norepinephrine in serum and the expression of tyrosine hydroxylase in bone marrow could be significantly elevated by chronic stress. Protein Tyrosine Kinase inhibitor Moreover, propranolol, an inhibitor of β-adrenergic signaling, could inhibit breast carcinoma metastasis and prevent the expansion of chronic stress-induced MDSCs. Further study revealed that the expressions of IL-6 and JAK/STAT3 signaling pathways were upregulated by chronic stress in mice, and this upregulation could be inhibited by propranolol. Blocking the IL-6 signal or inhibiting the activation of the JAK/STAT3 signaling pathway could reduce tumor growth and metastasis by attenuating the accumulation of MDSCs in vivo. Besides, propranolol inhibited the expression of IL-6 in supernatant of 4T1 cells induced by isoproterenol and reduced the proportion of inducible MDSCs in vitro. Taken together, these data indicated that chronic stress may accumulate MDSCs via activation of β-adrenergic signaling and IL-6/STAT3 pathway, thereby promoting breast carcinoma metastasis.Diffuse large B-cell lymphoma (DLBCL) is an aggressive malignancy arising from germinal center or post-germinal center B-cells that retain many of the properties of normal B-cells. Here we show that a subset of DLBCL express the cytokine IL-10 and its receptor. The genetic ablation of IL-10 receptor signaling abrogates the autocrine STAT3 phosphorylation triggered by tumor cell-intrinsic IL-10 expression and impairs growth of DLBCL cell lines in subcutaneous and orthotopic xenotransplantation models. Furthermore, we demonstrate using an immunocompetent Myc-driven model of DLBCL that neutralization of IL-10 signaling reduces tumor growth, which can be attributed to reduced Treg infiltration, stronger intratumoral effector T-cell responses, and restored tumor-specific MHCII expression. The effects of IL-10R neutralization were phenocopied by the genetic ablation of IL-10 signaling in the Treg compartment and could be reversed by MHCII blockade. The BTK inhibitor ibrutinib effectively blocked tumor cell-intrinsic IL-10 expression and tumor growth in this Myc-driven model. Tumors from patients with high IL-10RA expression are infiltrated by higher numbers of Tregs than IL-10RAlow patients. Finally, we show in 16 cases of DLBCL derived from transplant patients on immunosuppressive therapy that IL-10RA expression is less common in this cohort, and Treg infiltration is not observed.Chimeric antigen receptor (CAR) T-cell therapy combines antigen-specific properties of monoclonal antibodies with the lytic capacity of T cells. An effective and safe CAR-T cell therapy strategy relies on identifying an antigen that has high expression and is tumor specific. This strategy has been successfully used to treat patients with CD19 + B-cell acute lymphoblastic leukemia (B-ALL). Finding a suitable target antigen for other cancers such as acute myeloid leukemia (AML) has proven challenging, as the majority of currently targeted AML antigens are also expressed on hematopoietic progenitor cells (HPCs) or mature myeloid cells. Herein, we developed a computational method to perform a data transformation to enable the comparison of publicly available gene expression data across different datasets or assay platforms. The resulting transformed expression values (TEVs) were used in our antigen prediction algorithm to assess suitable tumor-associated antigens (TAAs) that could be targeted with CAR-T cells. We validated this method by identifying B-ALL antigens with known clinical effectiveness, such as CD19 and CD22.