スタチンはYAP制御を介してゲムシタビンの肝内胆管癌抑制効果を増強させる

Cholangiocarcinoma (CCA) is associated with high mortality rates because of its resistance to conventional gemcitabine-based chemotherapy. Hydroxy-methyl-glutaryl-coenzyme A reductase inhibitors (statins) reportedly exert anti-cancer effects in CCA and lower the risk of CCA; however, the underlying mechanism of these effects remains unclear. The proliferative and oncogenic activities of the transcriptional co-activator Yes-associated protein (YAP) are driven by its association with the TEA domain (TEAD) of transcription factors; thereby, upregulating genes that promote cell growth, inhibit apoptosis, and confer chemoresistance. This study investigated the effects of atorvastatin in combination with gemcitabine on the progression of human CCA associated with YAP oncogenic regulation. Both atorvastatin and gemcitabine concentration-dependently suppressed the proliferation of HuCCT-1 and KKU-M213 human CCA cells. Moreover, both agents induced cellular apoptosis by upregulating the pro-apoptotic marker BAX and downregulating the anti-apoptotic markers MCL1 and BCL2. Atorvastatin also significantly decreased the mRNA expression of the TEAD target genes CTGF, CYR61, ANKRD1, and MFAP5 in both CCA cell lines. A xenograft tumor growth assay indicated that atorvastatin and gemcitabine potently repressed human CCA cell-derived subcutaneous tumor growth by inhibiting YAP nuclear translocation and TEAD transcriptional activation. Notably, the anti-cancer effects of the individual agents were significantly enhanced in combination. These results indicate that gemcitabine plus atorvastatin could serve as a potential novel treatment option for CCA.博士（医学）・甲第778号・令和3年3月15日© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

アンジオテンシンII 受容体拮抗薬であるロサルタンは、レンバチニブによるヒト肝癌細胞への 細胞増殖抑制性および血管新生抑制効果の感性を向上させる

Molecular targeted therapy with lenvatinib is commonly offered to advanced hepatocellular carcinoma (HCC) patients, although it is often interrupted by adverse effects which require a reduction in the initial dose. Thus, an alternative lenvatinib-based therapy to compensate for dose reduction is anticipated. This study aimed to assess the effect of combination of low-dose of lenvatinib and the angiotensin-II (AT-II) receptor blocker losartan on human HCC cell growth. In vitro studies found that losartan suppressed the proliferation by inducing G1 arrest and caused apoptosis as indicated by the cleavage of caspase-3 in AT-II-stimulated HCC cell lines (Huh-7, HLE, and JHH-6). Losartan attenuated the AT-II-stimulated production of vascular endothelial growth factor-A (VEGF-A) and interleukin-8 and suppressed lenvatinib-mediated autocrine VEGF-A production in HCC cells. Moreover, it directly inhibited VEGF-mediated endothelial cell growth. Notably, the combination of lenvatinib and losartan augmented the cytostatic and angiostatic effects of the former at a low-dose, reaching those achieved with a conventional dose. Correspondingly, a HCC tumor xenograft assay showed that the oral administration of losartan combined with lenvatinib reduced the subcutaneous tumor burden and intratumor vascularization in BALB/c nude mice. These findings support that this regimen could be a viable option for patients intolerant to standard lenvatinib dosage.博士（医学）・甲第813号・令和4年3月15日© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

アンギオテンシン受容体を遮断することによりYes関連蛋白質の発癌活性が阻害されて胆管癌細胞増殖が抑制される

Cholangiocarcinoma (CCA) is a destructive malignancy with limited responsiveness to conventional chemotherapy. Although angiotensin receptor blockers (ARBs) have gained attention for their potential anticancer activity, little is known about their effects on CCA. The transcriptional co-activator, Yes-associated protein (YAP) is a critical oncogene in several cancers, including CCA. Following recent evidence showing that YAP is regulated by angiotensin II (AT-II), we investigated the effects of an ARB, losartan, on two human CCA cell lines (KKU-M213 and HuCCT-1) with regards to YAP oncogenic regulation. Losartan suppressed AT-II-induced CCA cell proliferation in a dose-dependent manner, induced apoptosis, decreased YAP (Ser127), and downregulated the YAP target genes CTGF, CYR61, ANKRD1, and MFAP5. However, losartan did not affect epithelial-mesenchymal transition, differentiation, or stemness in the CCA cells. Xenograft tumor growth assay showed that oral administration of a low clinical dose of losartan considerably reduced subcutaneous tumor burden and attenuated intratumor vascularization in CCA cell-derived xenograft tumors in BALB/c nude mice. These results indicate that ARB therapy could serve as a potential novel strategy for CCA treatment.博士（医学）・甲第728号・令和2年3月16日Copyright © 2018 Elsevier B.V. All rights reserved

内視鏡的硬化療法の手技と治療成績における透明フードの有用性

Objective: Although the effectiveness of a transparent hood has been reported in various endoscopic procedures, there are only a few reports regarding the benefit of a transparent hood in endoscopic injection sclerotherapy(EIS). In the current study, we conducted a retrospective evaluation of the efficacy and long-term benefit of an oblique transparent hood on EIS. Methods: The transparent hood, manufactured by Olympus (MAJ295 or MAJ296), consisted of a reusable wide oblique distal attachment with rim. This hood was attached when the varix was fine (F0 or F1). In this retrospective study, a total of 201 patients were recruited, and 99 patients (designated as the "Hood Group") received this hood while 102 patients (designated as the "Conventional Group") did not. We compared the rate of intravariceal injection, enhanced supply vessels, variceal eradication, and recurrence between these two groups. Results: This transparent hood provided a better visual field, and there was no serious complication in any of the patients. Intravariceal injection rates in the Hood Group and Conventional Group were 73.9% (190/257) and 57.7% (146/253) respectively (p<0.01). The rates of enhanced supply vessels in the Hood Group and Conventional Group were 89.8% (89/99) and 72.5% (74/102) respectively (p<0.01). The rates of variceal eradication did not differ significantly. We also assessed the cumulative non-recurrence probability for up to 3000 days between the two groups. The Hood Group was statistically superior to the Conventional Group (p<0.01) Conclusion: The application of an oblique transparent hood method is safe and effective for intravariceal EIS. This hood contributes especially to reduction of the long-term recurrence probability.博士（医学）・乙第1365号・平成27年11月27

内視鏡超音波ガイド下穿刺吸引の液状検体の残余を用いたK-ras 遺伝子検査は正診率を高める

Background: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) technology is widely used for the diagnosis of pancreatic masses. However, in some cases, inadequate tissue volume or difficulty of morphological diagnosis are constraining factors for adequate cytopathological evaluation. K-ras mutation is the most frequently acquired genetic abnormality, occurring in approximately 90% of all patients with pancreatic ductal adenocarcinoma (PDAC). In the present study, the clinical utility of residual liquid-based cytology (LBC) specimens obtained using EUS-FNA for K-ras mutation analysis was evaluated. Methods: In this study, 81 patients with pancreatic lesions were examined. The cell block (CB) specimens separated from EUS-FNA samples were morphologically evaluated by hematoxylin-eosin (HE) staining. Final diagnoses were confirmed by CB specimens, surgical resection specimens, diagnostic imaging, and clinical follow-up. Genomic DNA of residual LBC specimens stored at 4°C for several months were extracted and assessed for K-ras mutations using a fluorescence resonance energy transfer-based preferential homoduplex formation assay. Results: K-ras mutation analysis using residual LBC samples was successful in all cases. The sensitivity, specificity, and accuracy of CB examination alone were 77.4%, 100%, and 81.3%, respectively, and those of the combination of CB examination and K-ras mutation analysis were 90.3%, 92.3%, and 90.7%, respectively. Furthermore, K-ras mutations were detected in 8 (57.1%) of 14 PDAC samples for which the CB results were inconclusive. Conclusion: These findings suggest that K-ras mutation analysis using residual LBC specimens improves the diagnostic accuracy of EUS-FNA.博士（医学）・乙第1492号・令和2年12月24日Copyright: © 2018 Sekita-Hatakeyama et al. This is an open access article distributed under the terms of the Creative Commons Attribution License(https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

ラットを用いた非アルコール生脂肪肝炎におけるアンジオテンシンⅡ受容体拮抗薬とリファキシミン併用薬投与による肝線維化抑制効果の検討

The progression of nonalcoholic steatohepatitis (NASH) is complicated. The multiple parallel-hits theory is advocated, which includes adipocytokines, insulin resistance, endotoxins, and oxidative stress. Pathways involving the gut-liver axis also mediate the progression of NASH. Angiotensin-II receptor blockers (ARB) suppress hepatic fibrosis via the activation of hepatic stellate cells (HSCs). Rifaximin, a nonabsorbable antibacterial agent, is used for the treatment of hepatic encephalopathy and has been recently reported to improve intestinal permeability. We examined the inhibitory effects on and mechanism of hepatic fibrogenesis by combining ARB and rifaximin administration. Fischer 344 rats were fed a choline-deficient/l-amino acid-defined (CDAA) diet for 8 weeks to generate the NASH model. The therapeutic effect of combining an ARB and rifaximin was evaluated along with hepatic fibrogenesis, the lipopolysaccharide-Toll-like receptor 4 (TLR4) regulatory cascade, and intestinal barrier function. ARBs had a potent inhibitory effect on hepatic fibrogenesis by suppressing HSC activation and hepatic expression of transforming growth factor-β and TLR4. Rifaximin reduced intestinal permeability by rescuing zonula occludens-1 (ZO-1) disruption induced by the CDAA diet and reduced portal endotoxin. Rifaximin directly affect to ZO-1 expression on intestinal epithelial cells. The combination of an ARB and rifaximin showed a stronger inhibitory effect compared to that conferred by a single agent. ARBs improve hepatic fibrosis by inhibiting HSCs, whereas rifaximin improves hepatic fibrosis by improving intestinal permeability through improving intestinal tight junction proteins (ZO-1). Therefore, the combination of ARBs and rifaximin may be a promising therapy for NASH fibrosis.博士（医学）・甲第780号・令和3年3月15日© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

スルフォラファンの肝癌発育抑制効果および血管新生抑制効果に関する基礎的検討

Sulforaphane (SFN) exhibits inhibitory effects in different types of cancers. However, its inhibitory effect on liver cancer remains unknown. This study aimed to determine the therapeutic potential of SFN for the treatment of liver cancer and explore the functional mechanisms underlying the inhibitory effects of SFN. Water-Soluble Tetrazolium salt (WST-1) assay was performed to assess the in vitro effect of SFN on cell proliferation in the human liver cancer cell lines, HepG2 and Huh-7. The mRNA levels of Nrf2 target genes and cell cycle-related genes were determined using quantitative RT-PCR. For assessing the inhibitory effect of SFN in vivo, we injected immortalized liver cancer cells into BALB/c nude mice as a xenograft model. SFN was orally administrated daily after tumor inoculation and continued for thirty-five days until their sacrifices. Nrf2 activation, induced by SFN, was confirmed by mRNA upregulation of HO-1, MRP2, and NQO1 in both the cell lines. Significant inhibition of liver cancer cell proliferation by SFN was shown in vitro in a dose-dependent manner by the downregulation of CCND1, CCNB1, CDK1 and CDK2. In in vivo studies, the administration of SFN significantly reduced the subcutaneous tumor burdens at the end of experiments by suppressing tumor cell proliferation, confirmed by Ki67 immunohistochemical analysis. The mRNA levels of CCND1, CCNB1, CDK1 and CDK2 were also decreased in these SFNtreated xenograft tumors. Moreover, CD34 immunostaining elucidated that the intratumoral neovascularization was markedly attenuated in the SFN-treated xenograft tumors. SFN exerts inhibitory effect on human liver cancer cells with antiangiogenic activity. The earlier version of this study was presented at the meeting of AASLD Liver Learning on Oct 2017.博士（医学）・甲第707号・平成31年3月15日© The Author(s) 2018 Under License of Creative Commons Attribution 3.0 License https://creativecommons.org/licenses/by/3.0

Salvage living donor liver transplantation after percutaneous transluminal angioplasty for recurrent Budd-Chiari syndrome: a case report

<p>Abstract</p> <p>Introduction</p> <p>Budd-Chiari syndrome is a very rare pathological entity that ultimately leads to liver failure. Several therapeutic modalities, including percutaneous transluminal angioplasty, have been attempted to save the life of patients with Budd-Chiari syndrome. Few reports have described a salvage living donor liver transplantation performed after percutaneous transluminal angioplasty in a patient with acute Budd-Chiari syndrome.</p> <p>Case presentation</p> <p>A 26-year-old Japanese man developed severe progressive manifestations, such as massive ascites and hematemesis due to rupture of esophageal varices. After making several investigations, we diagnosed the case as Budd-Chiari syndrome. We first performed percutaneous transluminal angioplasty to dilate a short-segment stenosis of his inferior vena cava. The first percutaneous transluminal angioplasty greatly improved the clinical manifestations. However, after a year, re-stenosis was detected, and a second percutaneous transluminal angioplasty failed to open the severe stricture of his inferior vena cava. Since our patient had manifestations of acute liver failure, we decided to perform salvage living donor liver transplantation from his brother. The transplantation was successfully performed and all clinical manifestations were remarkably alleviated.</p> <p>Conclusion</p> <p>In cases of recurrent Budd-Chiari syndrome, the blocked hepatic venous outflow is not always relieved, even with invasive therapies. We have to take into account the possibility of adopting alternative salvage therapies if the first therapeutic modalities fail. When invasive therapy such as percutaneous transluminal angioplasty fails, liver transplantation should be considered as an alternative option.</p

エスジーエルティー2阻害薬（カナグリフロジン）およびジペプチジルペプチダーゼ４阻害薬（テネリグリプチン）との併用療法は非糖尿病ラットモデルにおける非アルコール性脂肪肝炎の進行を抑制する

Hepatocellular carcinoma (HCC) is the strongest independent predictor of mortality in non-alcoholic steatohepatitis (NASH)-related cirrhosis. The effects and mechanisms of combination of sodium-dependent glucose cotransporter inhibitor and canagliflozin (CA) and dipeptidyl peptidase-4 inhibitor and teneligliptin (TE) on non-diabetic NASH progression were examined. CA and TE suppressed choline-deficient, L-amino acid-defined diet-induced hepatic fibrogenesis and carcinogenesis. CA alone or with TE significantly decreased proinflammatory cytokine expression. CA and TE significantly attenuated hepatic lipid peroxidation. In vitro studies showed that TE alone or with CA inhibited cell proliferation and TGF-β1 and α1 (I)-procollagen mRNA expression in Ac-HSCs. CA+TE inhibited liver fibrogenesis by attenuating hepatic lipid peroxidation and inflammation and by inhibiting Ac-HSC proliferation with concomitant attenuation of hepatic lipid peroxidation. Moreover, CA+TE suppressed in vivo angiogenesis and oxidative DNA damage. CA or CA+TE inhibited HCC cells and human umbilical vein endothelial cell (HUVEC) proliferation. CA+TE suppressed vascular endothelial growth factor expression and promoted increased E-cadherin expression in HUVECs. CA+TE potentially exerts synergistic effects on hepatocarcinogenesis prevention by suppressing HCC cell proliferation and angiogenesis and concomitantly reducing oxidative stress and by inhibiting angiogenesis with attenuation of oxidative stress. CA+TE showed chemopreventive effects on NASH progression compared with single agent in non-diabetic rat model of NASH, concurrent with Ac-HSC and HCC cell proliferation, angiogenesis oxidative stress, and inflammation. Both agents are widely, safely used in clinical practice; combined treatment may represent a potential strategy against NASH.博士（医学）・甲第765号・令和3年3月15日© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)