Search

Resistance to immunotherapy is one of the biggest problems of current oncotherapeutics. While T cell abundance is essential for tumor responsiveness to immunotherapy, factors that define the T cell-inflamed tumor microenvironment are not fully understood. We used an unbiased approach to identify tumor-intrinsic mechanisms shaping the immune tumor microenvironment (TME), focusing on pancreatic adenocarcinoma because it is refractory to immunotherapy and excludes T cells from the TME. From human tumors, we identified ephrin-A receptor 2 (EPHA2) as a candidate tumor-intrinsic driver of immunosuppression. Epha2 deletion reversed T cell exclusion and sensitized tumors to immunotherapy. We found that prostaglandin endoperoxide synthase 2 (PTGS2), the gene encoding cyclooxygenase- 2, lies downstream of EPHA2 signaling through TGF-[beta] and is associated with poor patient survival. Ptgs2 deletion reversed T cell exclusion and sensitized tumors to immunotherapy; pharmacological inhibition of PTGS2 was similarly effective. Thus, EPHA2/PTGS2 signaling in tumor cells regulates tumor immune phenotypes; blockade may represent a therapeutic avenue for immunotherapy-refractory cancers. Our findings warrant clinical trials testing the effectiveness of therapies combining EPHA2/TGF-[beta]/PTGS2 pathway inhibitors with antitumor immunotherapy and may change the treatment of notoriously therapy-resistant pancreatic adenocarcinoma., Introduction Immunotherapies, including immune checkpoint blockade (ICB), have led to significant improvement of clinical care for cancer patients (1-4). Patients with melanoma, lung adenocarcinoma, or kidney cancer have a 20%-40% [...]

Aim: Reports of patients with hepatitis B have highlighted associations between polymorphisms in the human leukocyte antigen (HLA)‐DPB1, CXCL13, and CXCR5 genes and disease pathology. Owing to its potential to contribute to the development of new diagnostic and therapeutic methods, we aimed to establish a reliable host genome analysis technique that can be used in countries with inadequate infrastructure. Method: We compared multiple commercially available kits for dried blood spot (DBS)‐based sample collection to develop a basic DBS‐based host genome analysis technique. We then collected blood samples from Cambodian patients with hepatitis B and performed single‐nucleotide polymorphism genotyping and HLA allele typing by the DBS system. Result: We were able to perform single‐nucleotide polymorphism genotyping and HLA allele typing with host DNA samples obtained using a combination of a HemaSpot™ filter paper‐based device and a SMITEST® EX‐R&D DNA extraction kit. The accuracy of genotyping using samples obtained by this method was not inferior to one using samples obtained by venipuncture. In the Cambodian population, significant associations of HLA‐DPB1*04:01 with protection against chronic hepatitis B virus (HBV) infection, and HLA‐DPB1*05:01 and HLA‐DPB1*13:01 with susceptibility to chronic HBV infection were identified. Conclusion: Based on the DBS system, we clarified the associations of HLA‐DPB1 alleles with chronic HBV infection in the Cambodian population for the first time. Because the DBS is a low‐cost, durable, transportable, and easy‐to‐handle modality, genetic analysis based on the DBS system is a feasible strategy for obtaining a deeper understanding of HBV epidemiology, especially in middle‐ or low‐income countries. [ABSTRACT FROM AUTHOR]

Background: The antidiabetic drugs sodium glucose cotransporter 2 inhibitors (SGLT2is) and thiazolidinediones have beneficial effects on the liver dysfunction of patients with nonalcoholic fatty liver disease and type 2 diabetes mellitus (T2DM). We aimed to determine the efficacy of these drugs for the treatment of liver disease in patients with metabolic dysfunction‐associated fatty liver disease (MAFLD) and T2DM. Methods: We undertook a retrospective study of 568 patients with MAFLD and T2DM. Of these, 210 were treating their T2DM with SGLT2is (n = 95), 86 with pioglitazone (PIO), and 29 with both. The primary outcome was the change in Fibrosis‐4 (FIB‐4) index between baseline and 96 weeks. Results: At 96 weeks, the mean FIB‐4 index had significantly decreased (from 1.79 ± 1.10–1.56 ± 0.75) in the SGLT2i group, but not in the PIO group. The aspartate aminotransferase to platelet ratio index, serum aspartate and alanine aminotransferase (ALT), hemoglobin A1c, and fasting blood sugar significantly decreased in both groups (ALT: SGLT2i group, −17 ± 3 IU/L; PIO group, −14 ± 3 IU/L). The bodyweight of the SGLT2i group decreased, but that of the PIO group increased (−3.2 kg and +1.7 kg, respectively). When the participants were allocated to two groups according to their baseline ALT (>30 IU/L), FIB‐4 index significantly decreased in both groups. In patients taking pioglitazone, the addition of SGLT2i improved liver enzymes but not FIB‐4 index for 96 weeks. Conclusions: Treatment with SGLT2i causes a larger improvement in FIB‐4 index than PIO in patients with MAFLD over 96 weeks. [ABSTRACT FROM AUTHOR]

Backgrounds and Aims: Toll‐like receptor (TLR) agonists have been developed as adjuvants to efficiently induce antiviral immune responses. Specificity and potency of these compounds are essential requirements for clinical trial applications. In patients with hepatitis B virus (HBV) infections, sustained loss of hepatitis B surface antigen (HBsAg) is a therapeutic goal, which may be achievable by the sequential activation of follicular helper T cells (Tfh) and antibody‐secreting B cells. We aimed to elucidate whether novel TLR7 agonist, GS‐986, could activate immune responses involved in HBV elimination. Methods: To clarify the impact of GS‐986 on pDCs, we quantified the expression levels of surface markers and evaluated for Tfh induction in a culture model consisting of human pDCs with allogeneic naïve CD4+ T cells. In addition, we examined whether GS‐986 could enhance HBs antibody production capacity using PBMC from CHB patients. Results: pDCs from CHB patients had lower OX40L expression and as well as impaired capacity for Tfh induction compared with those from healthy donors. However, GS‐986–stimulated pDCs from CHB patients expressed OX40L and produced IL‐6 and IL‐12, resulting in the induction of IL‐21–producing Tfh cells (CXCR5+PD‐1+CD4+) from naïve CD4+ T cells. The Tfh‐inducing capacity of GS‐986 was reduced in the presence of an anti‐OX40L blocking antibody. Furthermore, GS‐986 promoted HBsAg‐specific antibody production in PBMCs from CHB patients. Conclusions: GS‐986 is an adjuvant that stimulates pDCs to induce Tfh differentiation and antigen‐specific B‐cell production. This immune profile may be beneficial for therapeutic application as an immune modulator in CHB patients. [ABSTRACT FROM AUTHOR]

Aim: Congestive hepatopathy often leads to liver fibrosis and hepatocellular carcinoma. Imaging modalities provided clinical evidence that elevation of liver stiffness and tumor occurrence are mainly induced in the periphery of the liver in patients with congestive hepatopathy. However, clinical relevance of liver stiffness and liver fibrosis is unclear because liver congestion itself increases liver stiffness in congestive hepatopathy. It also unclear which factors configure such regional disparity of tumor development in patients with congestive hepatopathy. To answer these questions, we evaluated the macroscopic spatial distribution of liver fibrosis and tumors in the murine model of congestive hepatopathy. Methods: Chronic liver congestion was induced by partial ligation of the suprahepatic inferior vena cava. Distribution of liver congestion, fibrosis, and tumors in partial ligation of the suprahepatic inferior vena cava mice were assessed by histological findings, laser microdissection (LMD)‐based qPCR and enhanced computed tomography. LMD‐based RNA‐sequencing was performed to identify causal factors that promote tumor development in congestive hepatopathy. Results: Liver fibrosis was mainly induced in the periphery of the liver and co‐localized with distribution of liver congestion. Liver tumors were also induced in the periphery of the liver where liver congestion and fibrosis occurred. LMD‐based RNA‐sequencing revealed the upregulation of extracellular matrix/collagen fibril‐, wound healing‐, angiogenesis‐, morphogenesis‐, and cell motility‐related signaling pathways in periphery of liver compared with liver center. Conclusions: Our findings showed the experimental relevance of liver congestion, fibrosis, and tumor development in congestive hepatopathy, and may provide important locational information. Macroscopic regional disparity observed in this murine model should be considered to manage patients with congestive hepatopathy. [ABSTRACT FROM AUTHOR]

Epithelial plasticity, or epithelial‐to‐mesenchymal transition (EMT), is a well‐recognized form of cellular plasticity, which endows tumor cells with invasive properties and alters their sensitivity to various agents, thus representing a major challenge to cancer therapy. It is increasingly accepted that carcinoma cells exist along a continuum of hybrid epithelial–mesenchymal (E‐M) states and that cells exhibiting such partial EMT (P‐EMT) states have greater metastatic competence than those characterized by either extreme (E or M). We described recently a P‐EMT program operating in vivo by which carcinoma cells lose their epithelial state through post‐translational programs. Here, we investigate the underlying mechanisms and report that prolonged calcium signaling induces a P‐EMT characterized by the internalization of membrane‐associated E‐cadherin (ECAD) and other epithelial proteins as well as an increase in cellular migration and invasion. Signaling through Gαq‐associated G‐protein‐coupled receptors (GPCRs) recapitulates these effects, which operate through the downstream activation of calmodulin‐Camk2b signaling. These results implicate calcium signaling as a trigger for the acquisition of hybrid/partial epithelial–mesenchymal states in carcinoma cells. Synopsis: Cancer cells exist along a continuum of hybrid or partial EMT states. This is underpinned by a calcium‐dependent molecular mechanism in various carcinomas, resulting in the internalization of epithelial proteins. Calcium signaling induces a partial EMT (P‐EMT) phenotype characterized by the internalization of membranous E‐cadherin.Calcium induced P‐EMT tumor cells exhibit increased migration and invasion.P‐EMT is activated by Gαq associated GPCRs and downstream activation of calmodulin‐Camk2b signaling. [ABSTRACT FROM AUTHOR]

Congestive hepatopathy (CH) with chronic passive congestion is characterized by the progression of liver fibrosis without prominent inflammation and hepatocellular damage. Currently, the lack of reliable biomarkers for liver fibrosis in CH often precludes the clinical management of patients with CH. To explore fibrosis biomarkers, we performed proteome analysis on serum exosomes isolated from patients with CH after the Fontan procedure. Exosomal cluster of differentiation (CD)44 levels were increased in patients with CH compared to healthy volunteers and was accompanied by increases in serum levels of soluble CD44 and CD44 expression in the liver. To address the roles of CD44 in CH, we established a mouse model of chronic liver congestion by partial inferior vena cava ligation (pIVCL) that mimics CH by fibrosis progression with less inflammation and cellular damage. In the pIVCL mice, enhanced CD44 expression in hepatic stellate cells (HSCs) and deposition of its ligand hyaluronan were observed in the liver. Blood levels of soluble CD44 were correlated with liver fibrosis. The blockade of CD44 with specific antibody inhibited liver fibrosis in pIVCL mice and was accompanied by a reduction in S100 calcium‐binding protein A4 expression following activation of HSCs. Conclusion: Chronic liver congestion promotes fibrosis through CD44. This identifies CD44 as a novel biomarker and therapeutic target of liver fibrosis in patients with CH. [ABSTRACT FROM AUTHOR]

Aim: In patients with liver cirrhosis, high levels of serum myostatin are associated with poor prognosis. We aimed to clarify the influence of myostatin on the prognosis of patients with non‐alcoholic fatty liver disease–hepatocellular carcinoma (NAFLD‐HCC) without cirrhosis and on the progression of liver fibrosis. Methods: Serum myostatin levels were evaluated in 234 patients who underwent primary surgical resection for single HCC. To clarify the impact of myostatin on liver fibrosis, we established human primary liver fibroblasts from resected livers, and cultured them in the presence of myostatin. Results: The median age was 67.4 years, the median L3 skeletal muscle mass index was 44.4 cm2/m2, and the median body mass index was 23.4 kg/m2. Eighty‐two (35.0%) patients had sarcopenia (L3 skeletal muscle mass index: men <42, women <38 cm2/m2). The etiologies of liver disease were hepatitis B virus (n = 61), hepatitis C virus (n = 86), and non‐B non‐C hepatitis (n = 87) including NAFLD (n = 74). High preoperative serum myostatin and vascular invasion were independent predictors of poor overall survival (OS). High serum myostatin was associated with poor OS in patients with no sarcopenia (n = 152). In patients without advanced liver fibrosis (Fibrosis stage, 0–2; n = 58), high levels of serum myostatin were also associated with poor OS, regardless of sarcopenia. Serum myostatin levels were increased with the progression of liver fibrosis. Liver fibroblasts were activated and produced collagen following stimulation with myostatin. Conclusions: In patients with NAFLD‐HCC without advanced liver fibrosis, high levels of serum myostatin were associated with poor OS. Myostatin activated primary fibroblasts and stimulated collagen production. [ABSTRACT FROM AUTHOR]

Background: Hepatitis B surface antigen (HBsAg) loss is an ideal goal for chronic hepatitis B patients. Antiretroviral therapy (ART) in hepatitis B virus/human immunodeficiency virus-1 (HBV/HIV-1)-coinfected patients can lead to hepatic flare (HF) caused by immune reconstitution-induced inflammatory syndrome (IRIS). Here, we investigated the impact of IRIS-HF on HBsAg loss.Methods: This was a retrospective study of 58 HBV/HIV-1-coinfected subjects HBsAg-positive for ≥6 months before ART initiation and followed for ≥1 year (median 9.9 years) after ART initiation. We examined humoral factors in sera from healthy volunteers, HIV-monoinfected patients, and HBV/HIV-1-coinfected patients with IRIS-HF or acute hepatitis B infection.Results: During ART, HBsAg loss was observed in 20 of 58 HBV/HIV-1-coinfected patients (34.5%). Of the 58 patients, 15 (25.9%) developed IRIS-HF within 12 months of ART initiation. HBsAg loss was more frequent among patients who developed IRIS-HF (11/15, 73.3%) than those who did not (9/43, 20.9%). Multivariate analysis showed IRIS-HF was an independent predictor of subsequent HBsAg loss. Younger age and higher baseline HBV DNA titer were associated with IRIS-HF. Elevation of sCD163, not CXCL9, CXC10, CXCXL11, or CXCL13, was observed at IRIS-HF.Conclusions: IRIS-HF was associated with HBsAg loss in HBV/HIV-1-coinfected patients. [ABSTRACT FROM AUTHOR]

Cell replacement therapy for diabetes mellitus requires cost-effective generation of high-quality, insulin-producing, pancreatic β cells from pluripotent stem cells. Development of this technique has been hampered by a lack of knowledge of the molecular mechanisms underlying β-cell differentiation. The present study identified reserpine and tetrabenazine (TBZ), both vesicular monoamine transporter 2 (VMAT2) inhibitors, as promoters of late-stage differentiation of Pdx1-positive pancreatic progenitor cells into Neurog3 (referred to henceforth as Ngn3)-positive endocrine precursors. VMAT2-controlled monoamines, such as dopamine, histamine and serotonin, negatively regulated β-cell differentiation. Reserpine or TBZ acted additively with dibutyryl adenosine 3',5'-cyclic AMP, a cell-permeable cAMP analog, to potentiate differentiation of embryonic stem (ES) cells into β cells that exhibited glucose-stimulated insulin secretion. When ES cell-derived β cells were transplanted into AKITA diabetic mice, the cells reversed hyperglycemia. Our protocol provides a basis for the understanding of β-cell differentiation and its application to a cost-effective production of functional β cells for cell therapy. [ABSTRACT FROM AUTHOR]

The endoderm-inducing effect of the mesoderm-derived supportive cell line M15 on embryonic stem (ES) cells is partly mediated through the extracellular matrix, of which laminin a5 is a crucial component. Mouse ES or induced pluripotent stem cells cultured on a synthesized basement membrane (sBM) substratum, using an HEK293 cell line (rLN10-293 cell) stably expressing laminin-511, could differentiate into definitive endoderm and subsequently into pancreatic lineages. In this study, we investigated the differentiation on sBM of mouse and human ES cells into hepatic lineages. The results indicated that the BM components played an important role in supporting the regional-specific differentiation of ES cells into hepatic endoderm. We show here that knockdown of integrin b1 (Itgb1) in ES cells reduced their differentiation into hepatic lineages and that this is mediated through Akt signaling activation. Moreover, under optimal conditions, human ES cells differentiated to express mature hepatocyte markers and secreted high levels of albumin. This novel procedure for inducing hepatic differentiation will be useful for elucidating the molecular mechanisms controlling lineage-specific fates during gut regionalization. It could also represent an attractive approach to providing a surrogate cell source, not only for regenerative medicine, but also for pharmaceutical and toxicologic studies. [ABSTRACT FROM AUTHOR]

Overall response rates of systemic therapies against advanced hepatocellular carcinoma (HCC) remain unsatisfactory. Thus, searching for new immunotherapy targets is indispensable. NK cells are crucial effectors and regulators in the tumor microenvironment and a determinant of responsiveness to checkpoint inhibitors. We revealed the landscape of NK cell phenotypes in HCC patients to find potential immunotherapy targets. Using single cell mass cytometry, we analyzed 32 surface markers on CD56dim and CD56bright NK cells, which included Sialic acid-binding immunoglobulin-type lectins (Siglecs). We compared peripheral NK cells between HCC patients and healthy volunteers. We also compared NK cells, in terms of their localizations, on an individual patient bases between peripheral and intrahepatic NK cells from cancerous and noncancerous liver tissues. In the HCC patient periphery, CD160+CD56dim NK cells that expressed Siglec-7, NKp46, and NKp30 were reduced, while CD49a+CD56dim NK cells that expressed Siglec-10 were increased. CD160 and CD49a on CD56dim NK cells were significantly correlated to other NK-related markers in HCC patients, which suggested that CD160 and CD49a were signature molecules. CD49a+ CX3CR1+ Siglec-10+ NK cells had accumulated in HCC tissues. Considering further functional analyses, CD160, CD49a, CX3CR1, and Siglec-10 on CD56dim NK cells may be targets for immunotherapies of HCC patients. [ABSTRACT FROM AUTHOR]

Summary The biological and functional heterogeneity between tumors—both across and within cancer types—poses a challenge for immunotherapy. To understand the factors underlying tumor immune heterogeneity and immunotherapy sensitivity, we established a library of congenic tumor cell clones from an autochthonous mouse model of pancreatic adenocarcinoma. These clones generated tumors that recapitulated T cell-inflamed and non-T-cell-inflamed tumor microenvironments upon implantation in immunocompetent mice, with distinct patterns of infiltration by immune cell subsets. Co-injecting tumor cell clones revealed the non-T-cell-inflamed phenotype is dominant and that both quantitative and qualitative features of intratumoral CD8 + T cells determine response to therapy. Transcriptomic and epigenetic analyses revealed tumor-cell-intrinsic production of the chemokine CXCL1 as a determinant of the non-T-cell-inflamed microenvironment, and ablation of CXCL1 promoted T cell infiltration and sensitivity to a combination immunotherapy regimen. Thus, tumor cell-intrinsic factors shape the tumor immune microenvironment and influence the outcome of immunotherapy. [ABSTRACT FROM AUTHOR]

Summary Epithelial-mesenchymal transition (EMT) is strongly implicated in tumor cell invasion and metastasis. EMT is thought to be regulated primarily at the transcriptional level through the repressive activity of EMT transcription factors. However, these classical mechanisms have been parsed out almost exclusively in vitro , leaving questions about the programs driving EMT in physiological contexts. Here, using a lineage-labeled mouse model of pancreatic ductal adenocarcinoma to study EMT in vivo , we found that most tumors lose their epithelial phenotype through an alternative program involving protein internalization rather than transcriptional repression, resulting in a “partial EMT” phenotype. Carcinoma cells utilizing this program migrate as clusters, contrasting with the single-cell migration pattern associated with traditionally defined EMT mechanisms. Moreover, many breast and colorectal cancer cell lines utilize this alternative program to undergo EMT. Collectively, these results suggest that carcinoma cells have different ways of losing their epithelial program, resulting in distinct modes of invasion and dissemination. [ABSTRACT FROM AUTHOR]