Endovascular Treatment of Postpancreatectomy Hemorrhage from the Retroportal Artery with Compression of the Celiac Trunk by the Median Arcuate Ligament: A Case Report.

Retroportal artery is one of the communicating arteries between the hepatic artery and the superior mesenteric artery, but it is often a small artery and usually unrecognized. We report a 60-year-old man that was successfully treated for postpancreatectomy hemorrhage from the retroportal artery with compression of the celiac trunk by the median arcuate ligament. Following the pancreaticoduodenectomy, the bloody discharge was discovered through the drainage catheter. We underwent transcatheter arterial embolization for the bleeding from the retroportal artery associated with a postoperative pancreatic fistula. Additionally, because a stenosis of the common hepatic artery was discovered, we consequently installed a stent-graft on the common hepatic artery to prevent the liver failure due to decreased hepatic blood flow.

Incidence of Hyper Progressive Disease in Combination Immunotherapy and Anti-Programmed Cell Death Protein 1/Programmed Death-Ligand 1 Monotherapy for Unresectable Hepatocellular Carcinoma.

Introduction: Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) signaling blockade is the most effective strategy for the treatment of immune evading hepatocellular carcinoma (HCC). While immune checkpoint inhibitor has revolutionized the concept of cancer treatment, it has also led to unexpected tumor growth. Regulatory T cells express PD-1 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) receptors, which are proliferated and activated by antibody binding, and their ratio to CD8+ T cells is altered, which is one of the causes for hyper progressive disease (HPD). We examined the frequency of HPD in anti-PD-1/PD-L1 monotherapy and combination therapy with vascular endothelial growth factor (VEGF) antibody and anti-CTLA-4 antibodies. Methods: This was a prospective and retrospective cohort study which enrolled 198 patients with unresectable HCC from January 2015 to December 2021 at the Kindai University Hospital. Fifty-eight patients received anti-PD-1/PD-L1 monotherapy, 119 patients combination with VEGF antibody, and 21 patients combination with anti-CTLA-4 antibody. We defined HPD as tumor growth rate (TGR) ratio ≥4, ΔTGR ≥40%, and tumor growth kinetics ratio ≥4. Results: The HPD rate was 10.3% (6/58) in anti-PD-1/PD-L1 monotherapy, 1.7% (2/119) in combination with VEGF antibody, and 4.8% (1/21) in combination with anti-CTLA-4 antibody (p = 0.034). The odds ratio for HPD in the combined anti-CTLA-4 antibody group was 0.433 (95% confidence interval [CI]: 0.05-3.83) when compared to the anti-PD-1/PD-L1 monotherapy group and 2.93 (95% CI: 0.25-33.79) when compared to the combined VEGF antibody group. Conclusion: The frequency of HPD in unresectable HCC compared to anti-PD-1/PD-L1 monotherapy was decreased with the combination with anti-VEGF antibody and not increased with anti-CTLA-4 antibody. Anti-PD-1/PD-L1 combined with anti-CTLA-4 antibody is now available in real-world and needs to be further validated with accumulated clinical practice.

Two Distinct Characteristics of Immune Microenvironment in Human Hepatocellular Carcinoma with Wnt/ß-Catenin Mutations.

Introduction: Immunotherapy is becoming a promising approach for unresectable-hepatocellular carcinoma (HCC); the anti-tumor response is affected by the tumor microenvironment (TME). Although Wnt/ß-catenin mutations are reported to cause non-inflamed phenotype, their role on TME remains controversial. We aimed to clarify the heterogeneity of immunophenotype in HCC with Wnt/ß-catenin mutations. Methods: This study includes 152 resected HCCs; mutations in the catenin beta-1, adenomatous polyposis coli, or AXIN1, or AXIN2 genes were defined as Wnt/ß-catenin mutations. With hierarchical cluster analyses, TME was classified into inflamed or non-inflamed classes based on the gene expressions associated with T-cell activation. Expression profiles of molecules related to cell differentiation and biliary-stem cell markers were compared between the TME classes to investigate whether differences in tumor traits were associated with TME. Results: Forty of 152 (26.3%) HCCs carried the Wnt/ß-catenin mutations. Of these, 33 were classified as non-inflamed (33/40, 82.5%) and 7 as inflamed (7/40, 17.5%). Non-inflamed class was characterized by low number of CD3+, CD4+, and CD8+ cells on immunostaining, and high mRNA expressions of AXIN2 and GLUL, which are involved in the canonical Wnt/ß-catenin signaling and hepatocyte differentiation, respectively. Non-inflamed tumors showed higher enhancement on the hepatobiliary-phase of gadolinium-ethoxybenzyl-diethylenetriamine (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) compared to inflamed tumors. HCCs classified as inflamed class are revealed to have high numbers of CD3+, CD4+, and CD8+ tumor infiltrating lymphocytes on immunostaining. This class is associated with increased expression of anti-epithelial cell adhesion molecule and FOXM1 accompanied by upregulation of genes related to interferon-gamma signaling, dendritic cell migration, regulatory T cells, and myeloid-derived suppressor cell activation and recognized as low enhancement nodule on Gd-EOB-DTPA-enhanced MRI. Conclusion: Heterogeneity of tumor traits and TME was observed in HCC with Wnt/ß-catenin mutation. The potential was indicated that tumor traits and TME are determined not only by the activation of the HNF4A but also by FOXM1, both of which are downstream transcription factor of the Wnt/ß-catenin signaling pathway.

A tumor endothelial cell-specific microRNA replacement therapy for hepatocellular carcinoma.

Current approved anti-angiogenic drugs (AAD) for hepatocellular carcinoma (HCC) inhibit tumor angiogenesis, but affect the hepatic vasculature resulting in adverse effects. Tumor endothelial cells (TECs) differ from normal endothelial cells. In this study, we aimed to detect TEC-specific miRNAs and develop an anti-angiogenic treatment specific for TECs. We established HCC orthotopic mouse models. TEC-specific miRNAs were detected using a microRNA array. Finally, we evaluated the therapeutic effects of the TEC-specific miRNA agonist cocktail. In total, 260 TEC-specific genes were detected. Among the top ten downregulated TEC-specific miRNAs, miR-139-3p and 214-3p were important for the TEC phenotype. The TEC-specific microRNA agonist cocktail showed significant anti-tumor effects by inhibiting tumor angiogenesis without affecting hepatic vasculatures in HCC orthotopic mouse models. Moreover, it significantly downregulated tip-cell sprouting-related genes. We identified two downregulated TEC-specific miRNAs; microRNA replacement therapy, which targets the downregulated TEC-specific miRNAs, is an effective and promising treatment for HCC.