{"title":"Reactive Mesothelial Cells in the Lymphatic Network of the Serous Membrane in Prolonged Body Fluid Retention: An Autopsy Case Report.","authors":"Yuji Nitta, Tomoko Uchiyama, Hisae Suzuki, Fumi Okada, Maiko Takeda, Chiho Ohbayashi, Akihiko Yoshizawa","doi":"10.1111/pin.70028","DOIUrl":"10.1111/pin.70028","url":null,"abstract":"<p><p>Reactive mesothelial cells (RMCs) are of interest for differentiating mesothelioma from benign conditions and have been discussed in cytology and biopsy; however, their behavior in the body remains poorly understood. In this study, we report an autopsy case of an older woman with a long-standing pleural effusion due to cardiac disease, providing insights into the relationship between body cavities, and lymphatic vessels (LVs), mesothelial cells (MCs), and endothelial cells. Cytological examination of pleural effusion revealed RMCs with mild atypia, multinucleation, and intercellular phagocytosis. Immunohistochemistry confirmed the mesothelial origin of these cells. Autopsy findings showed extensive involvement of RMCs in the pleura, diaphragm, peritoneum, lymph vessels, and lymph node sinuses. The visceral pleural submesothelial LVs were dilated, had small openings in the thoracic cavity, and were lined with endothelial and mesothelial cells. Large cavernous LVs with MC clusters were observed on the diaphragm. These structures resembled \"stomata\" or \"lacunae,\" suggesting a mechanism by which RMCs migrate from the body cavities to the lymphatic network. This study focuses on the RMCs in LVs and shows the contiguity between body cavities and lymphatic networks, providing important insights into the flow of bodily fluids.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"373-378"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144128208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"MYCBP2 Expression Correlates With Poor Prognosis in Upper Tract Urothelial Carcinoma Patients.","authors":"Lee-Moay Lim, Yi-Chen Lee, Wei-Chi Hsu, Wen-Yu Chung, Hui-Hui Lin, Ting-Wei Lin, Hung-Lung Ke, Wei-Ming Li, Wen-Jeng Wu, Hung-Tien Kuo, A-Mei Huang","doi":"10.1111/pin.70029","DOIUrl":"10.1111/pin.70029","url":null,"abstract":"<p><p>The incidence of upper tract urothelial carcinoma (UTUC) in Taiwan is high, characterized by aggressive clinical behavior and a tendency to be more invasive at diagnosis. Identifying tumorigenic genes remains an important challenge. Myc binding protein 2 (MYCBP2) regulates the cAMP, p38MAPK, TSC/mTOR, and autophagy signaling pathways in mammalian cells. MYCBP2 dysfunction has been associated with poor prognosis in leukemia, melanoma, colon, and prostate cancer. Its role in UTUC needs to be clarified. We investigated the expression of MYCBP2 in UTUC and its relationship to patient outcomes. MYCBP2 expression levels were assessed by immunohistochemistry in 110 tissue samples from UTUC patients. Higher MYCBP2 protein expression was significantly correlated with worse disease-free survival (p = 0.001) and cancer-specific survival (p = 0.007). The major clinicopathological characteristics associated with MYCBP2 expression were stage, lymphovascular invasion, distant metastasis, recurrence, and cancer death. Based on multivariate analysis, pathological stage (HR:2.31, p = 0.017) and MYCBP2 expression (HR:2.75, p = 0.015) were significant predictors of disease-free survival in UTUC. MYCBP2 is elevated in UTUC cell lines compared with immortalized uroepithelial cells. Knocking down MYCBP2 significantly suppressed cellular migration and invasion activity in BFTC909 cells. In conclusion, MYCBP2 expression might predict poor survival among UTUC patients.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"349-358"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144199832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ayuna Sugai, Kosuke Miyai, Keiichi Ito, Susumu Matsukuma, Kimiya Sato
{"title":"Kidney Injury Molecule-1 Expression in Pathological T1b Clear Cell Renal Cell Carcinoma: A Putative Biomarker of High Immune-Inflamed Status and Recurrence.","authors":"Ayuna Sugai, Kosuke Miyai, Keiichi Ito, Susumu Matsukuma, Kimiya Sato","doi":"10.1111/pin.70024","DOIUrl":"10.1111/pin.70024","url":null,"abstract":"<p><p>Kidney injury molecule-1 (KIM-1) is a potential prognostic marker of advanced-stage clear cell renal cell carcinoma (ccRCC) and is associated with tumor immunogenicity. Little is known about its role in early-stage ccRCC, especially in pathological T1b (pT1b) disease, which shows a higher recurrence rate than pT1a disease. Resected specimens from 112 pT1b ccRCC cases were reviewed and immunohistochemically analyzed for KIM-1 expression. High membranous KIM-1 expression was defined as H score ≥ 140, based on the immunoreactive intensity and area, and cytoplasmic expression in ≥ 10% of cancer cells was considered as high cytoplasmic KIM-1 expression. KIM-1 expression status was compared with clinicopathological variables, including tumor-associated immune cell (TAIC) status. Among the 112 cases, high membranous and cytoplasmic KIM-1 expression was observed in 30 (27%) and 38 (34%) cases, respectively. High membranous KIM-1 expression was significantly associated with a higher nuclear grade, tumor necrosis, hot TAIC status, and shorter recurrence-free survival (RFS) and cancer-specific survival, whereas high cytoplasmic expression was only related to a higher nuclear grade. Multivariate Cox regression analysis revealed that high membranous KIM-1 expression and tumor necrosis were independent predictors of shorter RFS. Our results indicate that membranous KIM-1 expression could be a biomarker for predicting postnephrectomy recurrence in pT1b ccRCC.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"340-348"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12288442/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144027715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Koki Nakashima, Hitomi Hoshino, Zui Zhang, Tomoya O Akama, Nobuyuki Kondo, Seiki Hasegawa, Yoshitaka Sekido, Mana Fukushima, Tamotsu Ishizuka, Motohiro Kobayashi
{"title":"Expression of Heart Development Protein With EGF-Like Domains 1 (HEG1) Decorated With Low-Sulfated Keratan Sulfate in Human Malignant Pleural Mesothelioma.","authors":"Koki Nakashima, Hitomi Hoshino, Zui Zhang, Tomoya O Akama, Nobuyuki Kondo, Seiki Hasegawa, Yoshitaka Sekido, Mana Fukushima, Tamotsu Ishizuka, Motohiro Kobayashi","doi":"10.1111/pin.70033","DOIUrl":"https://doi.org/10.1111/pin.70033","url":null,"abstract":"<p><p>The glycoform of heart development protein with EGF-like domains 1 (HEG1) recognized by the SKM9-2 monoclonal antibody is a useful diagnostic marker for malignant pleural mesothelioma (MPM). The putative glycoform includes core 2 O-glycans carrying sialyl poly-N-acetyllactosamine (LacNAc), but sulfation modifications are undetermined. Since sialyl 6-sulfo LacNAc-capped core 2 O-glycans are expressed in MPM and their structure overlaps with low-sulfated keratan sulfate (KS), we asked whether low-sulfated KS is expressed in MPM and whether HEG1 is decorated with low-sulfated KS. We performed immunohistochemical analysis of 41 MPM cases using anti-KS monoclonal antibodies and endoglycosidases, reversed-phase ion-pair high-performance liquid chromatography analysis of KS/sulfated LacNAc isolated from human pleural tissue, and western blot analysis of HEG1·IgG recombinant fusion proteins secreted from low-sulfated KS-expressing human embryonic kidney cells. Most MPM tissues were stained with anti-low-sulfated KS antibodies and staining was eliminated by endo-β-galactosidase and keratanase II but not by peptide-N-glycosidase F. Disaccharide composition analysis revealed that mono-sulfated LacNAc disaccharide and di-sulfated LacNAc disaccharide accounted for 83.1% and 16.9% of pleural KS/sulfated LacNAc, respectively. Western blot analysis of HEG1·IgG glycoforms indicated that HEG1 functions as a core protein for low-sulfated KS. Thus, HEG1 protein decorated with low-sulfated KS is expressed in MPM.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144317583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Identification of Target Genes Using Innovative Screening Systems.","authors":"Keisuke Sugita, Morito Kurata","doi":"10.1111/pin.70019","DOIUrl":"10.1111/pin.70019","url":null,"abstract":"<p><p>Advances in cancer biology have been achieved by the identification of oncogenes and tumor suppressor genes through the remarkable progression of next-generation sequencing. New techniques, such as single-cell analysis, help uncover cancer progression and heterogeneity. Reverse genetic screenings, including methods like random mutagenesis via retroviruses, transposons, RNA interference, and CRISPR, are useful for exploring gene functions and their roles in cancer. Especially in random mutagenesis, CRISPR screening and its modifications have recently emerged as powerful tools due to their comprehensiveness and simplicity in inducing genetic mutations. Initially, CRISPR screening focused on analyzing biological phenotypes in a cell population. It has since evolved to incorporate advanced techniques, such as combining single-cell and spatial analyses. These developments enable the investigation of cell-cell and spatial interactions, which more closely mimic In Vivo microenvironments, offering deeper insights into complex biological processes. These approaches allow for the identification of essential genes involved in cancer survival, drug resistance, and tumorigenesis. Together, these technologies are advancing cancer research and therapeutic development.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"257-266"},"PeriodicalIF":2.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12184300/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144009584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chisato Ohe, Takashi Yoshida, Mahul B Amin, Steven C Smith, Masanori Shiohara, Nozomi Tsujio, Masahiro Kato, Rena Uno, Toyonori Tsuzuki, Kenichi Kohashi
{"title":"Comparison of Histologic Parameters and Predictive Gene Signatures in Clear Cell Renal Cell Carcinoma Response to Systemic Therapy.","authors":"Chisato Ohe, Takashi Yoshida, Mahul B Amin, Steven C Smith, Masanori Shiohara, Nozomi Tsujio, Masahiro Kato, Rena Uno, Toyonori Tsuzuki, Kenichi Kohashi","doi":"10.1111/pin.70012","DOIUrl":"10.1111/pin.70012","url":null,"abstract":"<p><p>Growing experience has correlated the histomorphological characteristics of clear cell renal cell carcinoma (ccRCC), ranging from cytoplasmic features to architectural patterns and tumor immune microenvironment, with clinical outcomes. However, further assessment is needed to determine which of these histologic parameters best correlate with outcomes of interest, especially response to tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs). Herein, we evaluated four histologic parameters: (i) World Health Organization (WHO)/International Society of Urological Pathology (ISUP) grade; (ii) clear and eosinophilic cytological phenotypes; (iii) immunophenotypes; and (iv) vascularity-based architectural classification, using hematoxylin and eosin-stained whole slide images for The Cancer Genome Atlas (TCGA) ccRCC cohort (n = 433). We then correlated these parameters with gene expression signatures associated with TKI and ICI response. Multivariate analysis found that the cytological phenotype and vascularity-based architectural classification were independently associated with an angiogenesis-related gene signature (both p < 0.05). Conversely, WHO/ISUP grade and immunophenotype were independently associated with effector T-cell and immune checkpoint gene signatures (both p < 0.05). In conclusion, histologic parameters, including cytological features, architectural patterns, and tumor immune microenvironment, are associated with gene signatures related to therapy response, with different parameters informative for TKIs versus ICIs. These findings may help guide prospective validation studies.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"267-277"},"PeriodicalIF":2.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12184299/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144161021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Human Papillomavirus-Related Adenosquamous Carcinoma of the Anorectum With Pagetoid Spread.","authors":"Kenta Seki, Taiki Hashimoto, Hiroshi Nagata, Dai Ogata, Shunsuke Tsukamoto, Hiroyuki Takamaru, Yukihide Kanemitsu, Shigeki Sekine","doi":"10.1111/pin.70018","DOIUrl":"10.1111/pin.70018","url":null,"abstract":"<p><p>Adenosquamous carcinoma is an uncommon type of cancer that comprises malignant squamous and glandular components. We present a case of human papillomavirus (HPV)-positive adenosquamous carcinoma of the anorectum, which exhibited extensive pagetoid spread, in a 70-year-old woman. The tumor had spread from the lower rectum to the perianal skin and was removed through a combined endoscopic and transanal surgical procedure. Histological examination revealed three morphologically distinct components: adenocarcinoma in the lower rectum, squamous intraepithelial neoplasia with a minor invasive squamous cell carcinoma component in the anal canal, and pagetoid spread of adenocarcinoma extending to the perianal skin. HPV18 DNA and diffuse p16 expression were detected in all three components, suggesting the integration of HPV and a histogenetic relationship among these morphologically distinct components. This case indicates that HPV-associated adenosquamous carcinoma also occurs in the anal canal, similar to the uterine cervix, and may present as secondary Paget's disease.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"315-319"},"PeriodicalIF":2.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143973353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Prominent Trabecular/Nested Growth Pattern in Mucoepidermoid Carcinoma May be Formed Primarily by the Fourth Cell Type, Namely Cells With a Columnar Cell Lineage.","authors":"Shinnichi Sakamoto, Fumio Ide, Miyako Hoshino, Michiko Nishimura, Kentaro Kikuchi","doi":"10.1111/pin.70016","DOIUrl":"10.1111/pin.70016","url":null,"abstract":"","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"323-325"},"PeriodicalIF":2.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143974814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kaoru Furihata, Waka Iwashita, Atsushi Kurabayashi, Kojima Koji, Mutsuo Furihata
{"title":"Ultrastructural and Immunohistochemical Study of a Gastric Bizarre Leiomyoma: Bizarre Nuclei and Prominent Cytoplasmic Processes Extending Into and Displacing the Stroma.","authors":"Kaoru Furihata, Waka Iwashita, Atsushi Kurabayashi, Kojima Koji, Mutsuo Furihata","doi":"10.1111/pin.70014","DOIUrl":"10.1111/pin.70014","url":null,"abstract":"<p><p>This study presents the ultrastructural and immunohistochemical findings of a gastric bizarre leiomyoma arising in the vestibule of a 79-year-old male. Histologically, loosely proliferating tumor cells consist of large, multinucleated, bizarre nuclei with intranuclear inclusions and abundant cytoplasm-containing vacuoles. A murky line was apparent between the tumor cells and eosinophilic and heterogenous stroma-like areas. Immunohistochemically, tumor cells exhibited positively stained dot patterns of α-smooth muscle actin and caldesmon, which were distributed in the cytoplasm of tumor cells and stroma-like regions. Ultrastructurally, tumor cells exhibited extended and complex cytoplasmic processes comprising the fascicles of filamentous fibers. These structures were also detected in the apparent stroma-like regions observed histologically and were consistent with the α-smooth muscle actin- and caldesmon-immunopositive dot structures. The original stromal areas remained as considerably narrow gaps between tumor cells with extended cytoplasmic processes. To the best of our knowledge, this is the first report detailing the unique ultrastructural and immunohistochemical characteristics of tumor cells and the limited stromal composition of an extremely rare primary gastric bizarre leiomyoma.</p>","PeriodicalId":19806,"journal":{"name":"Pathology International","volume":" ","pages":"310-314"},"PeriodicalIF":2.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12184308/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144041238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}