Satoshi Sumida, Mayuko Shimizu, Yuko Miyakami, Takumi Kakimoto, Tomoko Kobayashi, Yasuyo Saijo, Minoru Matsumoto, Hirohisa Ogawa, Takeshi Oya, Yoshimi Bando, Hisanori Uehara, Shu Taira, Mitsuo Shimada and Koichi Tsuneyama : Histological and immunohistochemical analysis of epithelial cells in epidermoid cysts in intrapancreatic accessory spleen., The Journal of Medical Investigation : JMI, Vol.70, No.1.2, 251-259, 2023.
(要約)
Novel histological features of epithelial cells of ECIPAS were indicated. Although more cases need to be evaluated, we propose that the cause of ECIPAS may be different from that of pancreatic ductal origin. J. Med. Invest. 70 : 251-259, February, 2023.
Mayuko Shimizu, Yosuke Tsuchiyama, Yuki Morimoto, Minoru Matsumoto, Tomoko Kobayashi, Satoshi Sumida, Takumi Kakimoto, Takeshi Oya, Hirohisa Ogawa, Michiko Yamashita, Satoru Matsuda, Katsuhisa Omagari, Shu Taira and Koichi Tsuneyama : A novel mouse model of non-alcoholic steatohepatitis suggests that liver fibrosis initiates around lipid-laden macrophages, The American Journal of Pathology, Vol.192, No.1, 31-42, 2022.
(要約)
Various cells, such as macrophages and hepatic stellate cells, interact in the generation of fibrosis in nonalcoholic steatohepatitis (NASH), but the mechanism remains unclear. We employed a high-fat/cholesterol/cholate (HFCC) diet to generate a model of NASH-related fibrosis and investigate the pathogenesis of fibrosis. Two mouse strains differing in susceptibility to obesity, the susceptible strain C57BL/6J and the relatively resistant strain A/J, developed hepatic histologic features of NASH, including fat deposition, intralobular inflammation, hepatocyte ballooning, and fibrosis, after 9 weeks of HFCC diet feeding. The severity of hepatic inflammation and fibrosis was greater in A/J mice than in C57BL/6J mice. A/J mice fed the HFCC diet exhibited characteristic CD204-positive lipid-laden macrophage aggregation in hepatic parenchyma. Polarized light visualized the Maltese cross (namely, cholesterol crystals within the aggregated macrophages). Moreover, fibrosis developed in a ring shape from the periphery of the aggregated macrophages (ie, the starting point of fibrosis could be visualized histologically). Furthermore, matrix-assisted laser desorption/ionization mass spectrometry imaging analysis detected a molecule at m/z 772.462, which corresponds to the protonated ion of phosphatidylcholine [P-18:1 (11Z)/18:0] and phosphatidylethanolamine [18:0/20:2 (11Z, 14Z)], in aggregated macrophages adjacent to the fibrotic lesions. In conclusion, the present HFCC diet-fed A/J model provides an ideal tool to study fibrogenesis and enables novel insights into the pathophysiology of NASH-related fibrosis.
Tomoko Kobayashi, Mayuko Shimizu, Takeshi Oya, Hirohisa Ogawa, Minoru Matsumoto, Yuki Morimoto, Satoshi Sumida, Takumi Kakimoto, Michiko Yamashita, Mitsuko Sutoh, Shunji Toyohara, Ryoji Hokao, Chunmei Cheng and Koichi Tsuneyama : Neonatal streptozotocin treatment rapidly causes different subtype of hepatocellular carcinoma without persistent hyperglycemia in 4CS mice fed on a normal diet., Pathology, Research and Practice, Vol.225, No.153559, 2021.
(要約)
Although diabetes mellitus (DM) is a well-known risk factor for hepatocellular carcinoma (HCC), the underlying mechanisms have not yet to be defined. We previously reported that DIAR mice fed with standard murine diet developed type 1 diabetes and HCC at age of 16 weeks old with a neonatal streptozotocin treatment (n-STZ). Because DIAR mice did not manifest obesity nor develop steatohepatitis, hyperglycemia with streptozotocin trigger or streptozotocin alone might turn on the hepato-carcinogenesis. An insulin-recruitment to DIAR-nSTZ mice showed an increased frequency of HCC during the first 12 weeks of age, although the diabetic indications notably improved. To elucidate the role of hyperglycemia in hepato-carcinogenesis, we performed a head-to-head comparative study by using 4CS mice and DIAR mice with n-STZ treatment. Newborn 4CS mice and DIAR mice were divided into STZ treated group and control group. The blood glucose levels of DIAR-nSTZ mice increased at age of eight weeks, while that of 4CS-nSTZ mice were maintained in the normal range. At eight weeks old, three out of five DIAR-nSTZ mice (60%) and one out of ten 4CS-nSTZ mice (10%) developed multiple liver tumors. At age of 12 weeks old, all eight of DIAR-nSTZ mice (100%) and two of 10 4CS-nSTZ mice (20%) developed multiple liver tumors. At 16 weeks old, all animals of DIAR-nSTZ and 4CS-nSTZ mice occurred liver tumors. DIAR-nSTZ showed hyperglycemia and HCC, and 4CS-nSTZ developed HCC without hyperglycemia. These results were interpreted that the onset of HCC maybe not related to the presence or absence of hyperglycemia but nSTZ treatment. On the other hand, since the carcinogenesis of 4CS-nSTZ is delayed compared to DIAR-nSTZ, hyperglycemia may play a role in the progression of carcinogenesis. Histologically, the liver tumor appeared irregularly trabecular arrangements of hepatocytes with various degrees of nuclear atypia. By immunohistochemical analyses, all liver tumors showed positive staining of glutamine synthetase (GS), an established human HCC marker. The expression pattern of GS was divided into a strong diffuse pattern and weak patchy pattern, respectively. The liver tumor showing the weak GS-patchy pattern expressed biliary/stem markers, EpCAM, and SALL4, partially. Because 4CS-nSTZ mice did not show any metabolic complications such as gaining body weight or high blood glucose level, it is a unique animal model with a simple condition to investigate hepatic carcinogenesis by excluding other factors.
Michittra Boonchan, Hideki Arimochi, Kunihiro Otsuka, Tomoko Kobayashi, Hisanori Uehara, Thiranut Jaroonwitchawan, Yuki Sasaki, Shin-ichi Tsukumo and Koji Yasutomo : Necroptosis protects against exacerbation of acute pancreatitis., Cell Death & Disease, Vol.12, No.6, 601, 2021.
(要約)
mice exhibit weight loss, edematous pancreatitis, necrotizing pancreatitis, and acinar cell dedifferentiation in response to tissue damage. Genetic deletion of Mlkl resulted in downregulation of the antiapoptotic genes Bclxl and Cflar in association with increases in the numbers of apoptotic cells, as detected by TUNEL assay. These findings suggest that RIPK3 and MLKL-mediated necroptosis exerts protective effects in AP and caution against the use of necroptosis inhibitors for AP treatment.
Naoki Miyamoto, Seiya Inoue, Takeshi Nishino, Masakazu Goto, Takahiro Yoshida, Tomoko Kobayashi, Yoshimi Bando, Hiromitsu Takizawa and Akira Tangoku : A CASE OF VAGUS NERVE SCHWANNOMA DIFFICULT TO DISTINGUISH FROM LYMPH NODAL METASTASIS OF ESOPHAGEAL CANCER., The Journal of Medical Investigation : JMI, Vol.68, No.1.2, 205-208, 2021.
(要約)
In this report, we describe a rare case of vagus nerve schwannoma associated with esophageal cancer. A 70-year-old man visited our hospital complaining of worsening dysphagia. His upper gastrointenstinal endoscopy revealed a mass in the esophagus. A contrast-enhanced chest computed tomography also detected a 15 mm nodule attached to the tracheal membrane. This nodule was diagnosed as a metastatic lymph node. Although the primary tumor reduced after neoadjuvant chemotherapy, the nodule remained intact ; it showed fluorodeoxyglucose accumulation on positron emission tomography. We had a clinical diagnosis of stage III after neoadjuvant chemotherapy and underwent surgery. Intraoperatively, the nodule could not be detached from the right vagus nerve ; therefore, we excised the nodule along with the adjacent vagus nerve. The nodule was pathologically diagnosed as a vagus schwannoma. The nodule was not a regional lymph node metastasis of esophageal cancer. His postoperative course was uneventful, and he is currently undergoing outpatient follow-up without recurrence. J. Med. Invest. 68 : 205-208, February, 2021.
Yoshimi Bando, Tomoko Kobayashi, Yuko Miyakami, Satoshi Sumida, Takumi Kakimoto, Yasuyo Saijo and Hisanori Uehara : Triple-negative breast cancer and basal-like subtype : Pathology and targeted therapy., The Journal of Medical Investigation : JMI, Vol.68, No.3.4, 213-219, 2021.
(要約)
Triple-negative breast cancer (TNBC) is a heterogenous disease. For personalized medicine, it is essential to identify and classify tumor subtypes to develop effective therapeutic strategies. Although gene expression profiling has identified several TNBC subtypes, classification of these tumors remains complex. Most TNBCs exhibit an aggressive phenotype, but some rare types have a favorable clinical course. In this review, we summarize the classification and characteristics related to the various TNBC subtypes, including the rare types. Therapeutic methods that are suitable for each subtype are also discussed. Of the intrinsic breast cancer subtypes identified by gene expression analysis, the basal-like subtype specifically displayed decreased expression of an estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) cluster. We also present results that characterize the TNBC and basal-like phenotypes. TNBC may be categorized into four major classes : basal-like, immune-enriched, mesenchymal, and luminal androgen receptor. Therapeutic strategies for each subtype have been proposed along with newly approved targeted therapies for TNBC, such as immune checkpoint inhibitors. Understanding the classification of TNBC based on gene expression profiling in association with clinicopathological factors will facilitate accurate pathological diagnosis and effective treatment selection. J. Med. Invest. 68 : 213-219, August, 2021.