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.

Deep Learning Analysis of Histologic Images from Intestinal Specimen Reveals Adipocyte Shrinkage and Mast Cell Infiltration to Predict Postoperative Crohn Disease.

Most patients with Crohn disease (CD), a chronic inflammatory gastrointestinal disease, experience recurrence despite treatment, including surgical resection. However, methods for predicting recurrence remain unclear. This study aimed to predict postoperative recurrence of CD by computational analysis of histopathologic images and to extract histologic characteristics associated with recurrence. A total of 68 patients who underwent surgical resection of the intestine were included in this study and were categorized into two groups according to the presence or absence of postoperative disease recurrence within 2 years after surgery. Recurrence was defined using the CD Activity Index and the Rutgeerts score. Whole-slide images of surgical specimens were analyzed using deep learning model EfficientNet-b5, which achieved a highly accurate prediction of recurrence (area under the curve, 0.995). Moreover, subserosal tissue images with adipose cells enabled highly accurate prediction. Adipose cell morphology showed significant between-group differences in adipose cell size, cell-to-cell distance, and cell flattening values. These findings suggest that adipocyte shrinkage is an important histologic characteristic associated with recurrence. Moreover, there was a significant between-group difference in the degree of mast cell infiltration in the subserosa. These findings show the importance of mesenteric adipose tissue in patient prognosis and CD pathophysiology. These findings also suggest that deep learning-based artificial intelligence enables the extraction of meaningful histologic features.

Identification of CXCL12-abundant reticular cells in human adult bone marrow.

A population of mesenchymal stem cells, termed CXC chemokine ligand (CXCL)12-abundant reticular (CAR) cells or leptin receptor-expressing cells, are the major cellular component of niches for haematopoietic stem cells (HSCs) in murine bone marrow. CAR cells are characterized by several salient features, including much higher expression of CXCL12, stem cell factor (SCF), forkhead box C1 (FOXC1) and early B-cell factor 3 (EBF3), which are essential for HSC maintenance, than other cells. However, the human counterpart of CAR cells has not been fully described. Here, we show the presence of cells expressing much higher CXCL12 than other cells in human adult bone marrow using a flow cytometry-based in situ technique that enables high-throughput detection of mRNA at single-cell resolution. Most CXCL12hi cells expressed high levels of SCF, FOXC1 and EBF3 and had the potential to differentiate into adipocytes and osteoblasts. Histologically, the nuclei of CXCL12hi cells were identified and quantified by EBF3 expression in fixed marrow sections. CXCL12hi cells sorted from residual bone marrow aspirates of chronic myeloid leukaemia patients expressed reduced levels of CXCL12, SCF, FOXC1 and EBF3 in correlation with increased leukaemic burden. Together, we identified the human counterpart of CAR cells, enabling the evaluation of their alterations in various haematological disorders by flow cytometric and histological analyses.

Bcl-2-negative IGH-BCL2 translocation-negative follicular lymphoma of the thyroid differs genetically and epigenetically from Bcl-2-positive IGH-BCL2 translocation-positive follicular lymphoma.

AIMS: Follicular lymphoma (FL), comprising a minor subset of primary thyroid lymphomas, is divided into two groups based on Bcl-2 expression and IGH-BCL2 translocation. The clinicopathological features exhibited by Bcl-2-negative IGH-BCL2 translocation-negative FL of the thyroid (Bcl-2- /IGH-BCL2- tFL) are different from those of conventional FL; however, its lymphomagenesis remains unclear. Here, we collected samples from seven patients with Bcl-2- /IGH-BCL2- tFL to investigate their epigenetic and genetic aberrations. METHODS AND RESULTS: The immunohistochemical profiles of epigenetic modifiers and the methylation status of histones were examined, including EZH2, MLL2/KMT2D, CBP/CREBBP, EP300, H3K27me3 and H3K4me3, in Bcl-2- /IGH-BCL2- tFL and Bcl-2-positive IGH-BCL2 translocation-positive FL of the thyroid (Bcl-2+ /IGH-BCL2+ tFL). Most Bcl-2- /IGH-BCL2- tFLs retained the positivity of epigenetic modifiers and lower expression of H3K27me3, although Bcl-2+ /IGH-BCL2+ tFLs exhibited aberrant immunohistochemical patterns of EZH2 and CBP/CREBBP and overexpression of H3K27me3. Samples from seven cases were further analysed using targeted sequencing, focusing on the exons of 409 key tumour suppressor genes and oncogenes. Bcl-2- /IGH-BCL2- tFLs do not have pathogenic mutations of epigenetic modifiers, such as EZH2, MLL2/KMT2D, MLL3/KMT2C, EP300 and ARID1A, which have been reported in FLs in the literature, whereas Bcl-2+ /IGH-BCL2+ tFLs are probably pathogenic/pathogenic missense mutations or frameshift mutations of these genes. Additionally, novel mutations in TET2 and EP400 were detected in Bcl-2- /IGH-BCL2- tFLs. CONCLUSIONS: Different genetic and epigenetic abnormalities might be involved in the oncogenesis of Bcl-2- /IGH-BCL2- tFLs from Bcl-2+ /IGH-BCL2+ tFLs and other FLs.

FAM111B enhances proliferation of KRAS-driven lung adenocarcinoma by degrading p16.

Lung cancer is a common type of cancer that represents a health problem worldwide; lung adenocarcinoma (LUAD) is a major subtype of lung cancer. Although several treatments for LUAD have been developed, the mortality rate remains high because of uncontrollable progression. Further biological and clinicopathological studies are therefore needed. Here, we investigated the role of family with sequence similarity 111 member B (FAM111B), which is highly expressed in papillary-predominant LUAD; however, its role in cancer is unclear. An immunohistochemical analysis confirmed that papillary-predominant adenocarcinomas exhibited higher expression of FAM111B, compared with lepidic-predominant adenocarcinomas. Additionally, FAM111B expression was significantly correlated with clinical progression. In vitro functional analyses using FAM111B-knockout cells demonstrated that FAM111B plays an important role in proliferation and cell cycle progression of KRAS-driven LUAD under serum-starvation conditions. Furthermore, FAM111B regulated cyclin D1-CDK4-dependent cell cycle progression by degradation of p16. In summary, we revealed the clinical importance of FAM111B in human tumor tissues, as well as its function as a degradative enzyme. Therefore, FAM111B has potential as a clinicopathological prognostic marker for LUAD.

Serum deprivation-response protein regulates aldehyde dehydrogenase 1 through integrin-linked kinase signaling in endometrioid carcinoma cells.

Endometrioid carcinoma (EC) is one of the most common malignancies of the female genital system. We reported previously that aldehyde dehydrogenase 1 (ALDH1), a predominant isoform of the ALDH family in mammals and a potential marker of normal and malignant stem cells, is related to the tumorigenic potential of EC. We compared the levels of various proteins in human EC cells with high and low ALDH1 expression using shotgun proteomics and found that serum deprivation-response protein (SDPR) was preferentially expressed in cells with high ALDH1 expression. Also known as cavin-2, SDPR is a member of the cavin protein family, which is required for the formation of caveolae. Using SDPR-knockout EC cells generated using the CRISPR/Cas9 system, we revealed that SDPR was correlated with invasion, migration, epithelial-mesenchymal transition, and colony formation, as well as the expression of ALDH1. RNA sequencing showed that integrin-linked kinase (ILK) signaling is involved in the effect of SDPR on ALDH1. Immunohistochemical analysis revealed that the localization of ILK at the cell cortex was disrupted by SDPR knockout, potentially interfering with ILK signaling. Moreover, immunohistochemical analysis of clinical samples showed that SDPR is related to histological characteristics associated with invasiveness, such as poor differentiation, lymphatic invasion, and the microcystic, elongated, and fragmented histopathological pattern. This is, to our knowledge, the first report that SDPR is related to tumor progression.

Adenylosuccinate lyase enhances aggressiveness of endometrial cancer by increasing killer cell lectin-like receptor C3 expression by fumarate.

Adenylosuccinate lyase (ADSL) is an enzyme that plays important roles in de novo purine synthesis. Although ADSL was reported to be upregulated in various malignancies, such as colorectal, breast, and prostate cancer, as well as gliomas, the mechanism by which elevated ADSL expression contributes to cancer has not been elucidated. We previously performed a shotgun proteomics analysis to characterize specific proteins associated with the properties of the aldehyde dehydrogenase (ALDH)-high cell population, which was reported to be involved in tumorigenic potential, and showed that ADSL expression is upregulated in the ALDH-high population of endometrial cancer. Here, we showed that ADSL is involved in endometrial cancer aggressiveness by regulating expression of killer cell lectin-like receptor C3 (KLRC3), which is a receptor expressed on natural killer cells. Immunohistochemical analysis indicated that ADSL expression increased as endometrioid carcinoma specimens became more poorly differentiated and higher degree of primary tumor progression. Knockdown of ADSL in endometrial cancer cells decreased cell proliferation, migration, and invasive capability, and caused the cells to adopt a more rounded shape. DNA microarray analysis and quantitative real-time PCR showed that KLRC3 expression was decreased in ADSL knockdown cells. Knockdown of KLRC3 in endometrial cancer cells resulted in the same phenotype as knockdown of ADSL. Moreover, fumarate, which could be produced by ADSL and was recently shown to be an oncometabolite, recovered KLRC3 expression in ADSL knockdown cells, suggesting that fumarate produced by ADSL could regulate KLRC3 expression. Our findings indicate that ADSL enhances cell proliferation, migration, and invasive capability through regulation of KLRC3 expression by fumarate.

Paraneoplastic autoimmune encephalitis associated with pleomorphic lung carcinoma: An autopsy case report.

A 64-year-old man was admitted with acute onset disturbed consciousness. Cerebrospinal fluid analysis revealed pleocytosis and elevated protein, with negative cultures and PCR. Serum antibodies for autoimmune encephalitis were also negative. Brain magnetic resonance imaging (MRI) was unremarkable, but whole-body CT scan showed a tumor in the left lower lung lobe. Bronchial brush cytology demonstrated clusters of malignant cells, and 18 F-fluorodeoxyglucose positron emission tomography showed multiple lesions and increased uptake in the lung tumor. Clinically the patient had a stage IV lung carcinoma, graded as T3N3M1b (OSS). Steroid therapy had limited efficacy, but chemotherapy dramatically improved his neurological symptoms. Therefore, he was diagnosed with paraneoplastic autoimmune encephalitis based on the diagnostic criteria for paraneoplastic neurological syndromes. He died due to disease progression 14 months later. Subsequent postmortem examination revealed white ill-defined nodules in the left lung, with similar nodules in other organs. The brain weighed 1500 g before fixation, and a nodule was observed in the right precentral gyrus. Microscopically, the lung tumor was a pleomorphic carcinoma with an adenocarcinoma component. Multiple areas of micro-softening (≤500 µm) were identified in the cerebral cortex, gray-white matter junction and basal ganglia, and were distributed diffusely in both the limbic and non-limbic systems. Mild lymphocytic infiltrates were observed involving few intraparenchymal vessels. Few tumor metastases were observed in the right precentral gyrus. The multiple micro-softenings may reflect a chronic neuropathologic change of paraneoplastic autoimmune encephalitis. They were too small to be detected by brain MRI. However, these lesions may have the potential to cause the neurological symptoms in the acute phase because they were observed in many anatomical regions. We should pay attention to subtle findings such as micro-softenings when estimating the neuropathology of autoimmune encephalitis. Further investigations are needed to understand the characteristic neuropathology of this condition.

S100A4 accelerates the proliferation and invasion of endometrioid carcinoma and is associated with the "MELF" pattern.

Endometrioid carcinoma (EC) is one of the most common malignancies of the female genital system. Although the behavior of EC ranges from an excellent prognosis to aggressive disease with a poor outcome, the factors that determine its diversity have not been determined. Here, we show that S100A4, a calcium-binding protein of the EF-hand type, is correlated with the proliferation and invasion ability of EC. We demonstrated previously that EC cells with high aldehyde dehydrogenase (ALDH) activity were more tumorigenic than ALDH-lo cells. Screening by shotgun proteomics demonstrated that the expression level of S100A4 in ALDH-hi EC cells was significantly higher than that in ALDH-lo cells. S100A4-knockout cells generated by the CRISPR/Cas9 system showed reduced proliferation and invasion. These cells showed impaired AKT phosphorylation and matrix metalloproteinase-2 activation, accounting for their impaired proliferation and invasion, respectively. Furthermore, in clinical EC samples, elevated expression of S100A4 was highly related to myometrial and lymphatic invasion in well to moderately differentiated EC. Notably, strong and diffuse expression of S100A4 was observed in tumor tissues with a microcystic, elongated and fragmented ("MELF") pattern, which is associated with a highly invasive EC phenotype. Collectively, our results demonstrate not only that high expression of S100A4 contributes to an aggressive phenotype of EC, but also that its elevated expression is closely related to the MELF histopathological pattern.

Differentiating Between Epstein-Barr Virus-positive Lymphoid Neoplasm Relapse and Post-transplant Lymphoproliferative Disorder After Sex-mismatched Hematopoietic Stem Cell Transplantation.

After allogeneic hematopoietic stem cell transplantation (HSCT), accurate differentiation between donor-derived post-transplant lymphoproliferative disorder (PTLD) and relapse of recipient-derived lymphoproliferative disorder (LPD) is crucial for determining treatment. Conventional diagnostic approaches for PTLD include histopathological examination, flow cytometry, and chimerism analysis of bulk tumor tissue. However, these methods are inconclusive in cases in which the primary disease is an Epstein-Barr virus (EBV)-positive LPD and is of the same lineage as that of the post-HSCT LPD tumor cells. Particularly, in cases where the number of tumor cells in the tissue is low, it is difficult to determine the origin of tumor cells. In this study, we developed a new method to simultaneously detect signals using sex chromosome fluorescence in situ hybridization, immunofluorescence staining, and EBV-encoded small RNA in situ hybridization on a single section of formalin-fixed paraffin-embedded histopathological specimen. The utility of the method was validated using specimens from 6 cases of EBV-positive LPD after sex-mismatched HSCT that were previously difficult to diagnose, including Hodgkin lymphoma-like PTLD that developed after HSCT for Hodgkin lymphoma and recurrence of chronic active EBV infection. This method successfully preserved the histologic structure after staining and allowed accurate determination of tumor cell origin and lineage at the single-cell level, providing a definitive diagnosis in all cases. This method provides a powerful tool for the diagnosis of LPDs after sex-mismatched HSCT.

Pathology of human organic mercury poisoning: Lessons from an autopsy case.

We had an opportunity to perform a general autopsy of a case with chronic organic mercury toxicosis in 2017. He had been engaged in synthesizing a variety of organic mercury compounds throughout the four years from 1966 and developed chronic organic mercury poisoning in 1969. Almost forty years on, he still remained to complain of persistent paresthesia at finger tips and tongue, and of narrowed visual field. Neurological examinations clarified a rise of two-point discrimination thresholds, a systemic increase of touch thresholds, constriction of the visual field caused by general visual depression, and sensorineural hearing loss while primary modalities of his somatic, visual, and auditory sensations were preserved. These symptoms and signs are characteristic of human organic mercury poisoning. Furthermore, he had difficulty in processing a lot of visual and auditory information at a time. His two-point discrimination thresholds and systemic elevation of touch thresholds were comparable to those of mild organic mercury poisoning cases. He had slight sensory ataxia, but not cerebellar ataxia. Brain [18F]-2-fluorodeoxyglucose positron emission tomography analysis exhibited marked hypometabolism at bilateral postcentral gyrus, striate cortex, and superior temporal gyrus, but not the cerebellum. Histopathological studies revealed considerable decrease of granular neurons and neuronal networks in bilateral primary somatosensory, visual, and auditory cortices. Those characteristic brain lesions fairly explain increase of thresholds of somatic, visual, and auditory sensations, and degradation of integrating sensory information. It is noted that damages to the peripheral nervous system and the cerebellum were not detected and that his intellectual faculties were preserved.

A Rare Case of Pseudo-Malignant Paranasal Extranodal Rosai-Dorfman Disease.

Rosai-Dorfman disease is a very rare disease characterized by histiocytic accumulation in the head and neck region and lymph node enlargement. We report a rare pseudo-malignant paranasal extranodal Rosai-Dorfman disease. A 69-year-old-man presented nasal bleeding and nasal obstruction. Paranasal mass was detected in the left nasal cavity and computed tomography (CT) findings are the sphenoid sinus, maxillary sinus, and ethmoid sinus were involved with inconstant bone thickening, however, no bone destruction was detected. Magnetic resonance imaging scans show iso-intensity signal in T1-weighed image and T2-weighed image. Positron emission tomography/CT fluorodeoxyglucose (FDG) uptake in posterior ethmoid sinus and sphenoid sinus, bilateral cervical lymph node, clavicle, and sternum. Based on the above results, we considered malignant lymphoma and performed a biopsy. After pathological examination, a diagnosis of Rosai-Dorfman disease was established.

Tumor cell plasticity in endometrioid carcinoma is regulated by neuronal membrane glycoprotein M6-b.

Tumor cell plasticity and tumor heterogeneity are involved in therapy resistance. Cancer stem cells (CSCs) refer to tumor cells that have the ability to self-renew, and generate the diverse cells that comprise the tumor and complicate tumor heterogeneity. In recent years, CSCs have been reported to emerge from non-CSCs, which is known as tumor cell plasticity; however, the mechanism has not been fully elucidated. The present study investigated tumor cell plasticity from the viewpoint of aldehyde dehydrogenase 1 family member A1 (ALDH1A1) activity, which is one of the markers of CSCs. In the endometrioid carcinoma cell line HEC-1B, the ALDH1A1-low population spontaneously yielded an ALDH1A1-high population, mimicking tumor cell plasticity, and it was revealed that the mixture of the ALDH1A1-high population with the ALDH1A1-low population sometimes accelerated the transition from an ALDH1A1-low to ALDH1A1-high population. Two distinct HEC-1B sublines were established. One of the two sublines accelerated such a transition and the other did not show such acceleration. In the former subline, the effect of the ALDH1A1-high population was abolished when the direct cell-cell contact between ALDH1A1-high and ALDH1A1-low populations was inhibited. By comparing the two sublines, the neuronal membrane glycoprotein M6-b (GPM6B) was identified as the candidate mediating tumor cell plasticity. GPM6B was expressed in the border of ALDH1A1-expressing tumor cells and non-expressing tumor cells in clinical samples of EC. Notably, knockout of GPM6B decreased ALDH1A1 expression, whereas its overexpression increased the expression of ALDH1A1, suggesting that GPM6B mediated the induction of ALDH1A1 and the plasticity of CSCs.

Mutually exclusive expression of EZH2 and H3K27me3 in non-small cell lung carcinoma.

Enhancer of zeste homolog 2 (EZH2) epigenetically represses gene expression via trimethylation of lysine 27 on histone 3 (H3K27me3). Non-small cell carcinoma (NSCLC) has been reported to show high EZH2 and low H3K27me3 expression compared to normal lung tissues, but there are no studies examining the expression of EZH2 and H3K27me3 simultaneously with immunohistochemistry. In the present study, the expression of EZH2 and H3K27me3 was examined in surgically resected NSCLC. We enrolled 27 cases of squamous cell carcinoma (SCC), 73 cases of Lepidic, 77 of Papillary/Acinar, 51 of Solid, 31 of Micropapillary, and 12 of Mucinous subtypes of adenocarcinoma. First, we examined the expression of EZH2 and H3K27me3 in normal and metaplastic bronchial epithelium adjacent to NSCLC. Normal bronchial epithelium showed EZH2 expression in a limited number of basal cells and H3K27me3 expression in surface differentiated cells with cilia or mucus. In metaplastic bronchial epithelium, the number of EZH2-positive cells increased in multilayered basal cells, and H3K27me3-positive cells were observed in the superficial layer. Then, EZH2 and H3K27me3 expression was analyzed in NSCLC. Abundant EZH2 and rare H3K27me3 expression was detected in SCC, Papillary/Acinar, Solid and Micropapillary subtypes. In Mucinous subtype, EZH2 expression was hardly detected, and H3K27me3 expression was detected in almost all tumor cells. EZH2-expressing and H3K27me3-expressing tumor cells were similarly observed in Lepidic subtype, but double immunofluorescence revealed that EZH2 and H3K27me3 expression pattern was mutually exclusive. No co-expression of EZH2 and H3K27me3 was detected in all examined subtypes. To our knowledge, there have been no reports describing mutually exclusive expression pattern of EZH2 and H3K27me3.

Nivolumab-induced systemic lymphadenopathy occurring during treatment of malignant melanoma: a case report.

Nivolumab is an anti-programmed cell death protein 1 monoclonal antibody that exhibits significant efficacy in treating melanoma and other malignancies. However, various nivolumab-induced immune-related adverse events (irAEs) have been reported, and differentiating irAEs from tumor progression is sometimes difficult. Here, we report a case of reactive lymphadenopathy occurring after treatment with nivolumab. A 56-year-old man with stage IIIC melanoma received adjuvant therapy with nivolumab after wide local excision. He developed systemic lymphadenopathy and autoimmune hemolytic anemia 1 month after receiving seven cycles of nivolumab. Pathological analysis of a cervical lymph node biopsy specimen revealed no metastatic lesion or any other malignancy, including lymphoma. Thus, the patient was diagnosed with nivolumab-induced reactive lymphadenopathy. Systemic corticosteroids were administered to reduce hemolysis, which led to the resolution of lymphadenopathy. When progressive lymphadenopathy is observed in a patient who received immune checkpoint inhibitor therapy, reactive lymphadenopathy should be carefully distinguished from progression to lymphoid metastasis, and biopsy should be performed if needed.

Nicotinamide N-methyltransferase is related to MELF pattern invasion in endometrioid carcinoma.

Grade 1 (G1) endometrioid carcinoma (EC) is relatively a good prognosis. However, in a minority of cases, G1 shows an aggressive histological pattern known as the microcystic, elongated, and fragmented (MELF) pattern. We previously reported that EC with high expression levels of S100A4 and serum deprivation-response protein (SDPR) was related to MELF pattern invasion. However, the molecular features of the invasive front area of the MELF pattern have not been investigated. In this study, we searched for genes preferentially expressed in the invasive front area of EC with the MELF pattern using laser microdissection and RNA sequencing, and showed that nicotinamide N-methyltransferase (NNMT) is related to MELF pattern invasiveness. Immunohistochemical analyses confirmed high NNMT expression in the invasive front area of the MELF pattern. Moreover, NNMT promoted migration, invasion, colony formation, epithelial-mesenchymal transition (EMT), and chemoresistance using EC cell lines. We speculate that depletion of NNMT promotes histone methylation and leads to tumor suppression because NNMT consumes S-adenosyl methionine (SAM), which is an essential methylation cofactor. NNMT knockout cells showed enhanced expression of H3K9me2. RNA sequencing using NNMT knockout cell lines suggested that methylation of H3K9 leads to repression of the transcription of various oncogenic genes. Our findings demonstrate the possibility that NNMT inhibitors, which are expected to be used for the treatment of metabolic disorders, would be effective for the treatment of aggressive EC. This is the first report of gene analyses focusing on the morphological changes associated with MELF pattern invasion of EC.

An immature inhibin-α-expressing subpopulation of ovarian clear cell carcinoma cells is related to an unfavorable prognosis.

Inhibin-α, a member of transforming growth factor-ß, is elevated in multiple tumors, but its specific roles are poorly understood. Here, we examined the feature of inhibin-α-expressing cells in ovarian tumors. Immunohistochemically, inhibin-α-expressing tumor cells were detected only in ovarian clear cell carcinoma (OCCC) among various types of ovarian tumors. By comparing the expression of inhibin-α and Ki-67, inhibin-α-expressing tumor cells were revealed to be less proliferative. When spheroids and chemoresistant cells were derived from OCCC cell lines, the expression level of inhibin-α was elevated, and that of an immature marker, aldehyde dehydrogenase, was also elevated. In consistent with this, inhibin-α expression was correlated with other immature markers, such as OCT3/4 and SOX2, and inversely correlated with proliferative marker MKI67 in public database on OCCC. Knockdown of inhibin-α in OCCC cell decreased chemoresistance. Moreover, prognostic analysis with 69 surgically resected OCCC cases revealed that the increased inhibin-α expression was an independent unfavorable prognostic factor. These findings suggested that inhibin-α-expressing subpopulation of OCCC tumor cells appeared to be less proliferative, immature, and angiogenic and to be related to acceleration of malignant progression.

Intraocular Endoscopy Resolved Tube Occlusion of an Ahmed Glaucoma Valve.

We report a case in which intraocular endoscopy clarified the cause of Ahmed glaucoma valve (AGV) failure with a cloudy cornea. A 42-year-old patient with glaucoma underwent AGV implant surgery to treat secondary glaucoma due to chronic iridocyclitis in his left eye. After AGV, he developed bullous keratopathy (BK) in that eye. After Descemet stripping automated endothelial keratoplasty (DSAEK) was performed to treat BK, the intraocular pressure (IOP) increased and early failure of the DSAEK resulted again in a cloudy cornea. We could not precisely detect any cause of AGV failure with ordinary imaging instrumentation. An intraocular endoscope was used to determine that cause, and we found that the fibrous tissue occluded the tube of the AGV. The IOP decreased soon after the tissue was removed. We conclude that intraocular endoscopy was useful for diagnosing AGV failure with BK.

Ectonucleotidase CD39 is highly expressed on ATLL cells and is responsible for their immunosuppressive function.

Adult T-cell leukemia/lymphoma (ATLL) patients have an extremely poor prognosis, partly due to their immunosuppressive state. The majority of ATLL patients have leukemic cells with phenotype similar to Tregs, prompting suggestions that ATLL cells themselves have immunosuppressive functions. In this study, we detected CD39 expression on ATLL cells, particularly frequent on aggressive subtypes. CD39 and CD73 convert extracellular adenosine triphosphate (ATP) into adenosine, a key player in Tregs' immunosuppression. In vitro culture, both CD39+ ATLL cells and normal Tregs converted rapidly extracellular ATP to AMP, which was disturbed by CD39 inhibitors, and was negated in the CD39 knockout MJ cell line. The proliferation of cocultured CD4+/CD8+ normal T cells was suppressed by CD39+ MJ cells, but not by CD39 knockout MJ cells. Supplemented ATP was exhausted by an EG7-OVA T-cell line with stable CD39 induction, but not by mock. When these cell lines were subcutaneously transplanted into murine flanks, Poly(I:C) peritoneal administration reduced tumor size to 1/3 in mock-transplanted tumors, but not in CD39 induced tumors. Overall, we found that ATLL cells express CD39 at a high rate, and our results suggest that this helps ATLL cells escape antitumor immunity through the extracellular ATPDase-Adenosine cascade. These findings will guide future clinical strategies for ATLL treatment.