Keratin 6A Is Expressed at the Invasive Front and Enhances the Progression of Colorectal Cancer.

Keratins (KRTs) are intermediate filament proteins in epithelial cells, and they are important for cytoskeletal organization. KRT6A, classified as a type II KRT, is normally expressed in stratified squamous epithelium and squamous cell carcinomas. Little is known about the expression and role of KRT6A in adenocarcinomas. We investigated the clinicopathologic and molecular biological significance of KRT6A in colorectal adenocarcinoma. Immunostaining of colorectal adenocarcinoma cases treated at our institution demonstrated that KRT6A showed significantly stronger expression at the invasive front than that at the tumor center (P < .0001). The high KRT6A-expression cases (n = 47) tended to have a high budding grade associated with significantly worse prognoses. A multivariate analysis revealed that the KRT6A expression status was an independent prognostic factor for overall survival (P = .0004), disease-specific survival (P = .0097), and progression-free survival (P = .0033). The correlation between KRT6A and patient prognoses was also validated in an external cohort from a published data set. To determine the function of KRT6A in vitro, KRT6A was overexpressed in 3 colon cancer cell lines: DLD-1, SW620, and HCT 116. KRT6A overexpression increased migration and invasion in DLD-1 but did not in SW620 and HCT116. In 3-dimensional sphere-forming culture, KRT6A expression enhanced the irregular protrusion around the spheroid in DLD-1. Our findings in this study indicated that KRT6A expression is a valuable prognostic marker of colorectal cancer and KRT6A may be involved the molecular mechanism in the progression of invasive areas of colorectal cancer.

Genomic Analysis of Undifferentiated Carcinoma of the Pancreas with Squamous Differentiation: A Case Report.

Pancreatic cancer is an intractable malignancy associated with a dismal prognosis. Undifferentiated carcinoma, a rare subtype, poses a clinical challenge owing to a limited understanding of its molecular characteristics. In this study, we conducted genomic analysis specifically on a case of undifferentiated carcinoma of the pancreas exhibiting squamous differentiation. An 80-year-old male, previously treated for colorectal cancer, presented with a mass with central cystic degeneration in the pancreatic tail. The mass was diagnosed pathologically as undifferentiated carcinoma of the pancreas with squamous differentiation. Despite surgical resection and chemotherapy, the patient faced early postoperative recurrence, emphasizing the aggressive nature of this malignancy. Genomic analysis of distinct histologic components revealed some common mutations between undifferentiated and squamous components, including Kirsten rat sarcoma virus (KRAS) and TP53. Notably, the squamous component harbored some specific mutations in SMARCA4 and SMARCB1 genes that code for members of the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complex. The common mutations in the undifferentiated and squamous cell carcinoma components from this analysis suggest that they originate from a common origin. The discussion also underscores the scarcity of genomic analyses on undifferentiated carcinoma of the pancreas, with existing literature pointing to SWI/SNF complex-related gene mutations. However, our case introduces chromatin remodeling factor mutations as relevant in squamous differentiation. In conclusion, this study provides valuable insights into the genomic landscape of undifferentiated pancreatic carcinoma with squamous differentiation. These findings suggest the importance of further research and targeted therapies to improve the management of undifferentiated carcinoma of the pancreas and enhance patient outcomes.

ECM1 and KRT6A are involved in tumor progression and chemoresistance in the effect of dexamethasone on pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) has a very poor prognosis. Neoadjuvant chemotherapy is an effective PDAC treatment option, but chemotherapy causes unfavorable side effects. Glucocorticoids (e.g., dexamethasone [DEX]) are administered to reduce side effects of chemotherapy for solid tumors, including pancreatic cancer. Glucocorticoids have both beneficial and detrimental effects, however. We investigated the functional changes and gene-expression profile alterations induced by DEX in PDAC cells. PDAC cells were treated with DEX, and the cell proliferation, migration, invasion, and chemosensitivity to gemcitabine (GEM) were evaluated. The results demonstrated decreased cell proliferative capacity, increased cell migration and invasion, and decreased sensitivity to GEM. A comprehensive genetic analysis revealed marked increases in ECM1 and KRT6A in DEX-treated PDAC cells. We evaluated the effects of ECM1 and KRT6A expression by using PDAC cells transfected with those genes. Neither ECM1 nor KRT6A changed the cells' proliferation, but each enhanced cell migration and invasion. ECM1 decreased sensitivity to GEM. We also assessed the clinicopathological significance of the expressions of ECM1 and KRT6A in 130 cases of PDAC. An immunohistochemical analysis showed that KRT6A expression dominated the poorly differentiated areas. High expressions of these two proteins in PDAC were associated with a poorer prognosis. Our results thus demonstrated that DEX treatment changed PDAC cells' functions, resulting in decreased cell proliferation, increased cell migration and invasion, and decreased sensitivity to GEM. The molecular mechanisms of these changes involve ECM1 and KRT6A, whose expressions are induced by DEX.

The Effect of Steatosis on Shear-Wave Velocity and Viscoelastic Properties Related to Liver Fibrosis Progression in Rat Models.

OBJECTIVE: Hepatic fibrosis has recently been evaluated using ultrasonography or magnetic resonance elastography. Although the shear wave velocity (SWV) obtained using point shear wave elastography (pSWE) provides a valuable measure of fibrosis, underlying steatosis may affect its measurement. METHODS: Using hepatic fibrosis samples, this study evaluated the effect of steatosis on the shear wave velocity of pSWE (Vs) and viscoelastic properties (assessed by dynamic mechanical analysis) of rat liver. Fifty rats with various grades of steatosis and fibrosis underwent open abdominal in vivo Vs measurements using a commercial ultrasound scanner. The mechanical properties of hepatic tissue were also characterized under ex vivo conditions using dynamic mechanical analysis and the Zener model of viscoelasticity. RESULTS: Fibrosis and steatosis progression influenced Vs and elasticity. The SWV computed using the Zener model and Vs showed a substantial correlation (r > 0.8). Fibrosis progression increased SWV. Steatosis was also related to SWV. Steatosis progression obscured the SWV change associated with fibrosis progression. CONCLUSION: We conclude that steatosis progression affects the evaluation of fibrosis progression. This finding could aid discrimination of non-alcoholic steatohepatitis from non-alcoholic fatty liver disease using SWV.

Imprint Cytology of Tall Cell Carcinoma with Reversed Polarity of the Breast: A Case Report.

INTRODUCTION: Tall cell carcinoma with reversed polarity (TCCRP) is a rare histologic subtype of breast cancer that was newly categorized in 2020. TCCRP is a relatively novel tumor, and there are no detailed reports about its cellular morphology. We were able to obtain imprint cytological specimens from fresh TCCRP tissue, and we provide our detailed observations. CASE PRESENTATION: The patient was a 73-year-old Japanese female with a 15-mm mass in her right breast. After invasive breast carcinoma was diagnosed based on a core needle biopsy, a lumpectomy was performed. The pathological examination revealed TCCRP, and Sanger sequencing detected IDH2 p.R172M hotspot mutation, which is characteristic of TCCRP. Soon after the surgery, the lumpectomy specimen was sliced before fixation for use in a clinical trial, and imprint cytological materials were obtained from the tumor's cut surface. Cytologically, the tumor showed papillary-like cell clusters and isolated cells with moderate cellularity. Neoplastic cell aggregates and clusters with thick vascular cores as the axis or with delicate fibrovascular stroma were observed. Most of the neoplastic cells were cuboidal-to-columnar in shape, with mildly to moderately irregularly shaped blunt nuclei. Some intranuclear cytoplasmic inclusions and nuclear grooves were present, resembling the nuclear findings of papillary thyroid carcinoma. The most characteristic finding was the columnar cell clusters with apically located nuclei, giving the impression of reversed polarity. CONCLUSION: We described cytological findings in TCCRP, a newly classified rare mammary tumor. Most of the characteristic histologic findings were also observed in imprint cytological specimens. Further studies on practical specimens such as fine-needle aspiration are needed for clinical application.

Serum elastase-1 predicts malignancy in intraductal papillary mucinous neoplasm of the pancreas.

BACKGROUND: The indication for surgical resection of intraductal papillary mucinous neoplasms (IPMNs) is defined by imaging features, such as mural nodules. Although carbohydrate antigen (CA) 19-9 was selected as a parameter for worrisome features, no serum biomarkers were considered when deciding on surgical indications in the latest international consensus guideline. In this study, we assessed whether clinical factors, imaging findings, and serum biomarkers are useful in predicting malignant IPMNs. METHODS: A total of 234 resected IPMN cases in Chiba University Hospital from July 2005 to December 2021 were retrospectively analyzed. RESULTS: Among the 234 patients with resected IPMNs diagnosed by preoperative imaging, 117 were diagnosed with malignant pathologies (high-grade dysplasia and invasive IPMNs) according to the histological classification. In the multivariate analysis, cyst diameter ≥30 mm; p = 0.035), enhancing mural nodules on multidetector computed tomography (≥5 mm; p = 0.018), and high serum elastase-1 (≥230 ng/dl; p = 0.0007) were identified as independent malignant predictors, while CA19-9 was not. Furthermore, based on the receiver operator characteristic curve analyses, elastase-1 was superior to CA19-9 for predicting malignant IPMNs. Additionally, high serum elastase-1 levels (≥230 ng/dl; p = 0.0093) were identified as independent predictors of malignant IPMNs in patients without mural nodules on multidetector computed tomography (MDCT) in multivariate analysis. CONCLUSION: The serum elastase-1 level was found to be a potentially useful biomarker for predicting malignant IPMNs.

Readministration of high-dose adeno-associated virus gene therapy vectors enabled by ImmTOR nanoparticles combined with B cell-targeted agents.

Tolerogenic ImmTOR nanoparticles encapsulating rapamycin have been demonstrated to mitigate immunogenicity of adeno-associated virus (AAV) gene therapy vectors, enhance levels of transgene expression, and enable redosing of AAV at moderate vector doses of 2 to 5E12 vg/kg. However, recent clinical trials have often pushed AAV vector doses 10-fold to 50-fold higher, with serious adverse events observed at the upper range. Here, we assessed combination therapy of ImmTOR with B cell-targeting drugs for the ability to increase the efficiency of redosing at high vector doses. The combination of ImmTOR with a monoclonal antibody against B cell activation factor (aBAFF) exhibited strong synergy leading to more than a 5-fold to 10-fold reduction of splenic mature B cells and plasmablasts while increasing the fraction of pre-/pro-B cells. In addition, this combination dramatically reduced anti-AAV IgM and IgG antibodies, thus enabling four successive AAV administrations at doses up to 5E12 vg/kg and at least two AAV doses at 5E13 vg/kg, with the transgene expression level in the latter case being equal to that observed in control animals receiving a single vector dose of 1E14 vg/kg. Similar synergistic effects were seen with a combination of ImmTOR and a Bruton's tyrosine kinase inhibitor, ibrutinib. These results suggest that ImmTOR could be combined with B cell-targeting agents to enable repeated vector administrations as a potential strategy to avoid toxicities associated with vector doses above 1E14 vg/kg.

Neuropathological features of levodopa-responsive parkinsonism in multiple system atrophy: an autopsy case report and comparative neuropathological study.

Background: In typical patients with multiple system atrophy with predominant parkinsonism (MSA-P) levodopa is ineffective. However, there are some of these patients who respond well to levodopa treatment. Levodopa efficacy in MSA-P patients is thought to be related to the degree of putaminal damage, but the pathological causation between the putaminal involvement and levodopa efficacy has not been established in detail. Objective: This study aimed to evaluate the neuropathological features of the nigrostriatal dopaminergic system in a "levodopa-responsive" MSA-P patient in comparison with "levodopa-unresponsive" conventional MSA-P patients. Materials and methods: Clinicopathological findings were assessed in a 53-year-old Japanese man with MSA who presented with asymmetric parkinsonism, levodopa response, and later wearing-off phenomenon. During autopsy, the nigrostriatal pathology of presynaptic and postsynaptic dopaminergic receptor density and α-synuclein status were investigated. The other two patients with MSA-P were examined using the same pathological protocol. Results: Four years after the onset, the patient died of sudden cardiopulmonary arrest. On autopsy, numerous α-synuclein-positive glial cytoplasmic inclusions in the basal ganglia, pons, and cerebellum were identified. The number of neurons in the putamen and immunoreactivity for dopamine receptors were well-preserved. In contrast, significant neuronal loss and decreased dopamine receptor immunoreactivity in the putamen were observed in the "levodopa-unresponsive" MSA-P control patients. These putaminal pathology results were consistent with the findings of premortem magnetic resonance imaging (MRI). All three patients similarly exhibited severe neuronal loss in the substantia nigra and decreased immunoreactivity for dopamine transporter. Conclusion: Levodopa responsiveness in patients with MSA-P may be corroborated by the normal putamen on MRI and the preserved postsynaptic nigrostriatal dopaminergic system on pathological examination. The results presented in this study may provide a rationale for continuation of levodopa treatment in patients diagnosed with MSA-P.

Rapamycin nanoparticles increase the therapeutic window of engineered interleukin-2 and drive expansion of antigen-specific regulatory T cells for protection against autoimmune disease.

Interleukin-2 (IL-2) therapies targeting the high affinity IL-2 receptor expressed on regulatory T cells (Tregs) have shown promising therapeutic benefit in autoimmune diseases through nonselective expansion of pre-existing Treg populations, but are potentially limited by the inability to induce antigen-specific Tregs, as well as by dose-limiting activation of effector immune cells in settings of inflammation. We recently developed biodegradable nanoparticles encapsulating rapamycin, called ImmTOR, which induce selective immune tolerance to co-administered antigens but do not increase total Treg numbers. Here we demonstrate that the combination of ImmTOR and an engineered Treg-selective IL-2 variant (termed IL-2 mutein) increases the number and durability of total Tregs, as well as inducing a profound synergistic increase in antigen-specific Tregs when combined with a target antigen. We demonstrate that the combination of ImmTOR and an IL-2 mutein leads to durable inhibition of antibody responses to co-administered AAV gene therapy capsid, even at sub-optimal doses of ImmTOR, and provides protection in autoimmune models of type 1 diabetes and primary biliary cholangitis. Importantly, ImmTOR also increases the therapeutic window of engineered IL-2 molecules by mitigating effector immune cell expansion and preventing exacerbation of disease in a model of graft-versus-host-disease. At the same time, IL-2 mutein shows potential for dose-sparing of ImmTOR. Overall, these results establish that the combination of ImmTOR and an IL-2 mutein show synergistic benefit on both safety and efficacy to provide durable antigen-specific immune tolerance to mitigate drug immunogenicity and to treat autoimmune diseases.

Gastric tumor mimicking bronchial tissue associated with a laryngotracheoesophageal cleft: a case report.

BACKGROUND: Laryngotracheoesophageal cleft (LTEC) is a rare disease in which the larynx and trachea communicate posteriorly to the esophagus. It is often associated with other congenital malformations, particularly gastrointestinal anomalies. Herein, we report a case of LTEC associated with a gastric polypoid lesion in bronchial tissue. CASE PRESENTATION: A gastric mass was detected in a male fetus since week 21 of gestation using fetal ultrasonography. Esophagogastroduodenoscopy performed after birth revealed a pedunculated polypoid lesion of the gastric fornix. The patient experienced frequent vomiting and aspiration pneumonia, which persisted after nasoduodenal tube feeding. Communication between the airway and esophagus was suspected. Laryngoscopy performed 30 days later revealed an LTEC (type III). Partial gastrectomy was performed when the patient was 93 days of age. Histopathological examination revealed tumor consisting of cartilage tissue covered with a layer of respiratory epithelium. CONCLUSION: The gastric tumor associated with LTEC exhibited structures mimicking bronchial tissue. LTEC occurs because of foregut maldevelopment, and the tumorous respiratory tissue in the stomach may have been formed from the same abnormal foregut development event as LTEC.

Phase 2 Dose-Finding Study in Patients with Gout Using SEL-212, a Novel PEGylated Uricase (SEL-037) Combined with Tolerogenic Nanoparticles (SEL-110).

INTRODUCTION: SEL-212 is a developmental treatment for uncontrolled gout characterized by serum uric acid (sUA) levels ≥ 6 mg/dl despite treatment. It comprises a novel PEGylated uricase (SEL-037; also called pegadricase) co-administered with tolerogenic nanoparticles containing sirolimus (rapamycin) (SEL-110; also called ImmTOR®), which mitigates the formation of anti-drug antibodies (ADAs) against uricase and SEL-037 (PEGylated uricase), thereby enabling sustained sUA control (sUA < 6 mg/dl). The aim of this study was to identify appropriate dosing for SEL-037 and SEL-110 for use in phase 3 clinical trials. METHODS: This open-label phase 2 study was conducted in adults with symptomatic gout and sUA ≥ 6 mg/dl. Participants received five monthly infusions of SEL-037 (0.2 or 0.4 mg/kg) alone or in combination with three or five monthly infusions of SEL-110 (0.05-0.15 mg/kg). Safety, tolerability, sUA, ADAs, and tophi were monitored for 6 months. RESULTS: A total of 152 adults completed the study. SEL-037 alone resulted in rapid sUA reductions that were not sustained beyond 30 days in most participants due to ADA formation and loss of uricase activity. Levels of ADAs decreased with increasing doses of SEL-110 up to 0.1 mg/kg, with anti-uricase titers < 1080 correlating with sustained sUA control and reductions in tophi. Overall, 66% of evaluable participants achieved sUA control at week 20 following five monthly doses of SEL-037 0.2 mg/kg + SEL-110 0.1-0.15 mg/kg, whereas only 26% achieved sUA control at week 20 when SEL-110 was withdrawn after week 12. Compared to other dose combinations, SEL-037 0.2 mg/kg + SEL-110 0.15 mg/kg achieved the greatest sUA control at week 12 and was well-tolerated with no safety concerns. CONCLUSION: Results provide continued support for the use of multiple monthly administrations of SEL-037 0.2 mg/kg + SEL-110 0.1-0.15 mg/kg in clinical trials for SEL-212. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT02959918.

Rescue of infant progressive familial intrahepatic cholestasis type 3 mice by repeated dosing of AAV gene therapy.

Background & Aims: Gene therapy using recombinant adeno-associated virus (rAAV) vector carrying multidrug resistance protein 3 (MDR3) coding sequence (AAV8-MDR3) represents a potential curative treatment for progressive familial intrahepatic cholestasis type 3 (PFIC3), which presents in early childhood. However, patients with the severest form of PFIC3 should receive treatment early after detection to prevent irreversible hepatic fibrosis leading ultimately to liver transplantation or death. This represents a challenge for rAAV-based gene therapy because therapeutic efficacy is expected to wane as rAAV genomes are lost owing to hepatocyte division, and the formation of AAV-specific neutralising antibodies precludes re-administration. Here, we tested a strategy of vector re-administration in infant PFIC3 mice with careful evaluation of its oncogenicity - a particular concern surrounding rAAV treatment. Methods: AAV8-MDR3 was re-administered to infant Abcb4 -/- mice 2 weeks after a first dose co-administered with tolerogenic nanoparticles carrying rapamycin (ImmTOR) given at 2 weeks of age. Eight months later, long-term therapeutic efficacy and safety were assessed with special attention paid to the potential oncogenicity of rAAV treatment. Results: Co-administration with ImmTOR mitigated the formation of rAAV-specific neutralising antibodies and enabled an efficacious second administration of AAV8-MDR3, resulting in stable correction of the disease phenotype, including a restoration of bile phospholipid content and healthy liver function, as well as the prevention of liver fibrosis, hepatosplenomegaly, and gallstones. Furthermore, efficacious repeat rAAV administration prevented the appearance of liver malignancies in an animal model highly prone to developing hepatocellular carcinoma. Conclusions: These outcomes provide strong evidence for rAAV redosing through co-administration with ImmTOR, as it resulted in a long-term therapeutic effect in a paediatric liver metabolic disorder, including the prevention of oncogenesis. Impact and implications: Redosing of gene therapy for inborn hepatobiliary disorders may be essential as effect wanes during hepatocyte division and renewal, particularly in paediatric patients, but the approach may carry long-term risks of liver cancer. Viral vectors carrying a therapeutic gene exerted a durable cure of progressive familial intrahepatic cholestasis type 3 in infant mice and reduced the risk of liver cancer only following a second administration.

Complex glandular pattern is an aggressive morphology that predicts poor prognosis of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignant neoplasm with various morphologies. Recognition of histological patterns that can predict prognosis is important in pathological examination. Recently, the complex glandular pattern was defined as a morphology associating the poor prognosis in lung adenocarcinoma. We investigated the significance of the complex glandular pattern in PDAC by performing a retrospective analysis. Among 240 consecutive cases of conventional PDACs, 21 cases in which complex glandular pattern constituted >50 % of the total tumor volume (CG-PDACs) were identified. The prevalence of CG-PDAC was 8.8 % among all preoperative therapy-naïve and surgically resected conventional PDACs. Compared to the control PDACs (n = 95), the CG-PDACs were characterized by significantly higher prevalence of small- to medium-sized artery invasion (71.4 % vs. 14.7 %, p < 0.0001), intratumoral necrosis (59.1 % vs. 16.8 %, p < 0.0001), tumor budding (mean: 15.5 vs. 12.5 per 0.785 mm2, p = 0.04), significantly higher Ki67 proliferative index (mean: 75.0 % vs. 54.7 %, p < 0.0001), and the HNF1α-/KRT81+ (quasi-mesenchymal) immunophenotype (42.9 % vs. 19.0 %, p = 0.004). In Kaplan-Meier analyses, the CG-PDAC patients achieved significantly worse disease-free survival (DFS) and overall survival (OS) compared to the control PDAC patients; the respective median DFS and OS were 6.3 and 17.7 months for CG-PDACs, and 22.6 and 52.8 months for control PDACs. A multivariate Cox regression analysis showed that predominance of complex glandular pattern was an independent prognostic factor (hazard ratio: 2.95; 95 % confidence interval: 1.46-5.98; p = 0.003). Our results provide new insights into the complex glandular pattern in conventional PDACs as a novel and potentially useful prognostic factor.

Bile proteome analysis by high-precision mass spectrometry to examine novel biomarkers of primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease of unknown etiology that affects the intra- and extrahepatic bile ducts. The present study examined the utility of a bile proteome analysis using a high-sensitivity mass spectrometer to comprehensively screen for novel PSC biomarkers. METHODS: Bile endoscopically collected from patients with PSC, common bile duct stones, and biliary tract cancer were subjected to high-precision liquid chromatography/mass spectrometry. Some of the proteins specifically up-regulated in the bile of the PSC group were re-examined by an enzyme-linked immunosorbent assay. RESULTS: A total of 8094 proteins were successfully identified and 332 were specifically up-regulated in the PSC group. The bioinformatics analysis showed that proteins involved in the proliferation and activation of diverse inflammatory cells were up-regulated in the PSC group. A receiver operating characteristic curve analysis showed good area under the curve values for interleukin-8 and annexin A1 (ANXA1) (0.836 and 0.914, respectively). Immunostaining for ANXA1 revealed its strong expression in inflammatory cells infiltrating the peripheral biliary tract in PSC livers. CONCLUSION: A bile proteome analysis is a useful tool for elucidating the pathogenesis of PSC and developing new diagnostic approaches. Therefore, ANXA1 has potential as a bile biomarker for PSC.

Ovarian Malignant Mixed Germ Cell Tumor Composed Mainly of a Polyembryoma Pattern With Vasculogenic Mesenchymal Tumor Components.

Ovarian germ cell tumors composed of numerous well-formed embryonal bodies have been described as exhibiting a "polyembryoma pattern." In addition, some germ cell tumors are occasionally concomitant with neoplastic vascular proliferation. These include angiosarcomas and the recently reported mediastinal vasculogenic mesenchymal tumors. A 9-yr-old Japanese girl underwent surgery for a right ovarian tumor. Histologically, the polyembryoma pattern, nongestational choriocarcinoma, and vasculogenic lesions characterized by a neoplastic repetition of embryonic vasculogenesis have been intermingled. The polyembryoma pattern consisted of numerous complete and incomplete embryonal bodies and glandular structures resembling adult-type and fetal-type intestines. Vasculogenic lesions were composed of variously developed neoplastic vessels within the myxomatous stroma, which extended well beyond one low-power (40×) microscopic field. We concluded that the vasculogenic lesion in our case was the ovarian counterpart of the mediastinal vasculogenic mesenchymal tumor. After the surgery, the patient was administered adjuvant chemotherapy and was alive with no evidence of recurrence or other malignancy at 28 mo postsurgery.

A case report of neuromyelitis optica spectrum disorder induced by pembrolizumab treatment for lung adenocarcinoma: a clinical and immunohistochemical study.

BACKGROUND: We report a case of neuromyelitis optica spectrum disorders (NMOSD), who developed after the pembrolizumab treatment, an immune checkpoint inhibitor, against lung adenocarcinoma. The present case is discussed with the lung adenocarcinoma specimen which was stained by aquaporin-4 (AQP4) and with literature review of NMOSD linked to immune checkpoint inhibitors. CASE PRESENTATION: A 62-year-old Japanese man presented with acute diencephalic syndrome, left optic neuritis, and myelitis 5 months after initiation of pembrolizumab treatment for lung adenocarcinoma. He was diagnosed with NMOSD based on serum anti-aquaporin-4 (AQP4) antibody positivity. Immunohistochemistry of lung biopsy samples showed AQP4 expression on CD68+ cells. This is the fifth reported case of AQP4+ NMOSD triggered by an immune checkpoint inhibitor and the first with a brain lesion. Four out of five NMOSD cases, including the present case and one case with lung metastasis, had lung cancer. CONCLUSIONS: Immune checkpoint inhibitors may trigger AQP4+ NMOSD owing to their molecular similarity to AQP4 expressed in lung and glial tissues. Prompt brain/spinal cord imaging and anti-AQP4 antibody testing may facilitate early diagnosis of immune-mediated adverse event in central nervous system associated with immune checkpoint inhibitors.

Clinicopathological and Genomic Features of Pediatric Intracranial Myxoid Mesenchymal Tumor with both of EWSR1-CREM Gene Fusion and MAP3K13 Mutation: A Case Report and Comparison with Adult Cases in the Literature.

Intracranial myxoid mesenchymal tumors (IMMTs) with EWSR1-CREB1 family gene fusion are rare brain neoplasms characterized by gene fusion between the EWSR1 gene and one of the cyclic AMP response element-binding (CREB) family transcription factor (CREB1, ATF1, or CREM) genes. Although half of reported cases are pediatric, the clinical, histologic, and genomic features of IMMTs with EWSR1 rearrangement in pediatric populations are not yet well clarified. Here we describe the case of a 7-year-old girl who presented with seizures due to an extra-axial tumor in the left parietal convexity. Gross total resection was achieved, and the tumor displayed a multilobular structure with solid hypercellular and myxoid hypocellular areas, separated by a variable amount of stroma. The hypercellular areas consisted of round to polygonal cells, whereas the myxoid areas were ovoid to spindled cells. Immunophenotypically, the tumor cells were positive for vimentin, desmin, and EMA. Next-generation sequencing of tumoral DNA revealed EWSR1-CREM gene fusion and a pathogenic mutation of MAP3K13. No recurrence was detected 9 months after resection, without chemotherapy or radiotherapy. In comparison to other pediatric and adult patients with EWSR1 rearrangement, many clinical, radiological, and immunohistochemical features were shared. However, signs of elevated intracranial pressure were more frequently observed, and postoperative radiation was less frequently administered for pediatric patients. Gross total resection (GTR) was the key prognostic factor for better disease control especially among pediatric patients. Further reports of cases with EWSR1 rearrangement with detailed genetic profiles are essential for clarifying the oncogenic pathway and establishing a standard treatment strategy.

A diet-induced murine model for non-alcoholic fatty liver disease with obesity and insulin resistance that rapidly develops steatohepatitis and fibrosis.

Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver disease worldwide. Patients with NAFLD often suffer steatohepatitis, which can progress to cirrhosis and hepatocellular carcinoma. The presence of visceral obesity or type 2 diabetes mellitus (T2DM) is a major risk factor and potential therapeutic target for NAFLD. The establishment of animal models with these metabolic comorbidities and with the rapid progression of the disease is needed for developing treatments for NAFLD but remains to be archived. In the present study, KK-Ay mice, widely used as T2DM models, or C57BL6 mice were fed a high-fat, high-fructose, and high-cholesterol diet supplemented with cholic acid (NAFLD diet). The KK-Ay mice fed a NAFLD diet exhibited remarkable obesity and insulin resistance. A prominent accumulation of triglycerides and cholesterol in the liver was observed at 4 weeks. These mice developed steatohepatitis at 4 weeks and fibrosis at 12 weeks. In contrast, C57BL6 mice fed a NAFLD diet remained lean, although they still developed steatohepatitis and fibrosis. In summary, we established a diet-induced murine NAFLD model with the rapid development of steatohepatitis and fibrosis, bearing obesity and insulin resistance. This model could be useful as preclinical models for drug development of NAFLD.