Ovarian high-grade serous carcinoma cells with low SMARCA4 expression and high SMARCA2 expression contribute to platinum resistance.

Platinum resistance is a major obstacle to the treatment of ovarian cancer and is correlated with poor clinical outcomes. Intratumor heterogeneity plays a key role in chemoresistance. Recent studies have emphasized the contributions of genetic and epigenetic factors to the development of intratumor heterogeneity. Although the clinical significance of multi-subunit chromatin remodeler, switch/sucrose nonfermenting (SWI/SNF) complexes in cancers has been reported, the impacts of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4/subfamily A, member 2 (SMARCA4/A2) expression patterns in human cancer tissues have not been fully elucidated. Here, we show that low expression of SMARCA4 and high expression of SMARCA2 are associated with platinum resistance in ovarian high-grade serous carcinoma (HGSC) cells. We used fluorescence multiplex immunohistochemistry (fmIHC) to study resected specimens; we examined heterogeneity in human HGSC tissues at the single-cell level, which revealed that the proportion of cells with the SMARCA4low /SMARCA2high phenotype was positively correlated with clinical platinum-resistant recurrence. We used stable transfection of SMARCA2 and siRNA knockdown of SMARCA4 to generate HGSC cells with the SMARCA4low /SMARCA2high phenotype; these cells had the greatest resistance to carboplatin. Bioinformatics analyses revealed that the underlying mechanism involved in substantial alterations to chromatin accessibility and resultant fibroblast growth factor (FGF) signaling activation, MAPK pathway activation, BCL2 overexpression, and reduced carboplatin-induced apoptosis; these were confirmed by in vitro functional experiments. Furthermore, in vivo experiments in an animal model demonstrated that combination therapy with carboplatin and a fibroblast growth factor receptor (FGFR) inhibitor promoted cell death in HGSC xenografts. Taken together, these observations reveal a specific subpopulation of HGSC cells that is associated with clinical chemoresistance, which may lead to the establishment of a histopathological prediction system for carboplatin response. Our findings may facilitate the development of novel therapeutic strategies for platinum-resistant HGSC cells. © 2023 The Pathological Society of Great Britain and Ireland.

Duodenal diverticulum metastasis from pulmonary squamous cell carcinoma diagnosed by EUS-FNA.

A 76-year-old male with pulmonary squamous cell carcinoma achieved complete response by chemoradiotherapy and subsequent systemic chemotherapy. During follow-up, fluorodeoxyglucose positron emission tomography/computed tomography showed strong fluorodeoxyglucose accumulation near the duodenal papilla. Elevated lesions were observed in the duodenal diverticulum upon lateral-viewing endoscopy, and a curved linear array echoendoscope showed a hypoechoic mass. Since it was difficult to obtain adequate tissue samples by endoscopic biopsy, endoscopic ultrasound-guided fine needle aspiration was performed for the hypoechoic mass. The pathological findings were squamous cell carcinoma, which was similar to the past histology of primary lung cancer. These findings indicated the diagnosis of duodenal diverticulum metastasis from pulmonary squamous cell carcinoma. Duodenal metastasis of pulmonary squamous cell carcinoma is a rare disease, and there have been no reports of duodenal diverticulum metastasis.

A Novel Three-Dimensional Imaging System Based on Polysaccharide Staining for Accurate Histopathological Diagnosis of Inflammatory Bowel Diseases.

BACKGROUND & AIMS: Tissue-clearing and three-dimensional (3D) imaging techniques aid clinical histopathological evaluation; however, further methodological developments are required before use in clinical practice. METHODS: We sought to develop a novel fluorescence staining method based on the classical periodic acid-Schiff stain. We further attempted to develop a 3D imaging system based on this staining method and evaluated whether the system can be used for quantitative 3D pathological evaluation and deep learning-based automatic diagnosis of inflammatory bowel diseases. RESULTS: We successfully developed a novel periodic acid-FAM hydrazide (PAFhy) staining method for 3D imaging when combined with a tissue-clearing technique (PAFhy-3D). This strategy enabled clear and detailed imaging of the 3D architectures of crypts in human colorectal mucosa. PAFhy-3D imaging also revealed abnormal architectural changes in crypts in ulcerative colitis tissues and identified the distributions of neutrophils in cryptitis and crypt abscesses. PAFhy-3D revealed novel pathological findings including spiral staircase-like crypts specific to inflammatory bowel diseases. Quantitative analysis of crypts based on 3D morphologic changes enabled differential diagnosis of ulcerative colitis, Crohn's disease, and non-inflammatory bowel disease; such discrimination could not be achieved by pathologists. Furthermore, a deep learning-based system using PAFhy-3D images was used to distinguish these diseases The accuracies were excellent (macro-average area under the curve = 0.94; F1 scores = 0.875 for ulcerative colitis, 0.717 for Crohn's disease, and 0.819 for non-inflammatory bowel disease). CONCLUSIONS: PAFhy staining and PAFhy-3D imaging are promising approaches for next-generation experimental and clinical histopathology.

An autopsy case of Alzheimer's disease with amygdala-predominant Lewy pathology presenting with frontotemporal dementia-like psychiatric symptoms.

Alzheimer's disease (AD) and frontotemporal dementia (FTD) are progressive neurodegenerative diseases associated with several cognitive and behavioral symptoms. It is sometimes difficult to distinguish AD from FTD in a patient because both of them can exhibit clinical overlap. In the present study, we report a case of a patient who showed sychiatric symptoms mimicking the behavioral variant of FTD (bvFTD) and combined AD amygdala-predominant Lewy pathologies on autopsy. The patient was a Japanese man who developed personality changes in his late 50s, presenting with obsessive-compulsive stereotypical behavior, stereotypy of speech, behavioral disinhibition, inertia, loss of empathy or sympathy, change in eating habits, and stimulus-bound behavior. He also frequently left during medical examinations. Eventually, he was clinically diagnosed as having possible bvFTD, according to the International Consensus Criteria for bvFTD. The patient died of systemic metastasis of gastric cancer at 69 years of age. Postmortem neuropathological examination revealed severe AD pathology (Braak Amyloid stage C, Consortium to Establish a Registry for Alzheimer's Disease [CERAD] stage C, Thal phase 5, and Braak AT8 stage IV) along with Lewy pathology and argyrophilic grains, predominantly in the amygdala. Furthermore, no transactivation response DNA-binding protein of 43 kDa (TDP-43) pathology was observed. Our results suggest that a combination of these pathologies causes bvFTD-like cognitive and behavioral symptoms. This case is very insightful when considering the lesions responsible for the psychiatric symptoms characteristic of bvFTD.

Atypical preeclampsia before 20 weeks of gestation with multicystic placenta, hyperreactio luteinalis, and elevated sFlt-1/PlGF ratio as manifestations of fetal triploidy: A case report.

Preeclampsia is one of the most common as well as most severe complications of pregnancy, characterized by new-onset hypertension and proteinuria or other organ dysfunction. It predominantly occurs after 20 weeks of gestation. Very rarely, it can be triggered earlier in some specific situations. Here we report a case of fetal triploidy presenting as an extraordinarily early-onset preeclampsia. A healthy 36-year-old multiparous woman who had conceived naturally was hospitalized due to acute-onset severe hypertension accompanied by proteinuria at 18 weeks of gestation. Laboratory testing ruled out the presence of underlying maternal disease. Ultrasound findings, including multicystic large placenta and multiple fetal anomalies, strongly suggested fetal triploidy. Maternal ovaries showed hyperreactio luteinalis. The soluble fms-like tyrosine kinase-1/ placental growth factor (sFlt-1/PlGF) ratio was elevated, at 270. Medical abortion was carried out at 19 weeks of gestation; thereafter, her symptoms quickly resolved. Fetal triploidy was confirmed by genetic testing. We should be aware that fetal disorders including triploidy as well as pre-existing maternal diseases can provoke such very early-onset preeclampsia. Fetal ultrasound evaluation is critical and the sFlt-1/PlGF ratio is important for prompt diagnosis and management to prevent adverse maternal outcomes associated with atypical preeclampsia before 20 weeks of gestation.