Galantamine ameliorates experimental pancreatitis.

BACKGROUND: Acute pancreatitis is a common and serious inflammatory condition currently lacking disease modifying therapy. The cholinergic anti-inflammatory pathway (CAP) is a potent protective anti-inflammatory response activated by vagus nerve-dependent α7 nicotinic acetylcholine receptor (α7nAChR) signaling using splenic CD4+ T cells as an intermediate. Activating the CAP ameliorates experimental acute pancreatitis. Galantamine is an acetylcholinesterase inhibitor (AChEI) which amplifies the CAP via modulation of central muscarinic ACh receptors (mAChRs). However, as mAChRs also activate pancreatitis, it is currently unknown whether galantamine would be beneficial in acute pancreatitis. METHODS: The effect of galantamine (1-6 mg/kg-body weight) on caerulein-induced acute pancreatitis was evaluated in mice. Two hours following 6 hourly doses of caerulein (50 µg/kg-body weight), organ and serum analyses were performed with accompanying pancreatic histology. Experiments utilizing vagotomy, gene knock out (KO) technology and the use of nAChR antagonists were also performed. RESULTS: Galantamine attenuated pancreatic histologic injury which was mirrored by a reduction in serum amylase and pancreatic inflammatory cytokines and an increase the anti-inflammatory cytokine IL-10 in the serum. These beneficial effects were not altered by bilateral subdiaphragmatic vagotomy, KO of either choline acetyltransferase+ T cells or α7nAChR, or administration of the nAChR ganglionic blocker mecamylamine or the more selective α7nAChR antagonist methyllycaconitine. CONCLUSION: Galantamine improves acute pancreatitis via a mechanism which does not involve previously established physiological and molecular components of the CAP. As galantamine is an approved drug in widespread clinical use with an excellent safety record, our findings are of interest for further evaluating the potential benefits of this drug in patients with acute pancreatitis.

Pancreatic Cancer Patient-derived Organoids Can Predict Response to Neoadjuvant Chemotherapy.

OBJECTIVE: To evaluate if patient-derived organoids (PDOs) may predict response to neoadjuvant (NAT) chemotherapy in patients with pancreatic adenocarcinoma. BACKGROUND: PDOs have been explored as a biomarker of therapy response and for personalized therapeutics in patients with pancreatic cancer. METHODS: During 2017-2021, patients were enrolled into an IRB-approved protocol and PDO cultures were established. PDOs of interest were analyzed through a translational pipeline incorporating molecular profiling and drug sensitivity testing. RESULTS: One hundred thirty-six samples, including both surgical resections and fine needle aspiration/biopsy from 117 patients with pancreatic cancer were collected. This biobank included diversity in stage, sex, age, and race, with minority populations representing 1/3 of collected cases (16% Black, 9% Asian, 7% Hispanic/Latino). Among surgical specimens, PDO generation was successful in 71% (15 of 21) of patients who had received NAT prior to sample collection and in 76% (39 of 51) of patients who were untreated with chemotherapy or radiation at the time of collection. Pathological response to NAT correlated with PDO chemotherapy response, particularly oxaliplatin. We demonstrated the feasibility of a rapid PDO drug screen and generated data within 7 days of tissue resection. CONCLUSION: Herein we report a large single-institution organoid biobank, including ethnic minority samples. The ability to establish PDOs from chemotherapy-naive and post-NAT tissue enables longitudinal PDO generation to assess dynamic chemotherapy sensitivity profiling. PDOs can be rapidly screened and further development of rapid screening may aid in the initial stratification of patients to the most active NAT regimen.

Malignant transformation of liver fatty acid binding protein-deficient hepatocellular adenomas: histopathologic spectrum of a rare phenomenon.

The molecular classification of hepatocellular adenomas highlights a distinctive genotype-phenotype correlation. Malignant transformation is an exceptionally rare complication of hepatocyte nuclear factor 1α (HNF1A)-inactivated hepatocellular adenomas. This subtype is characterized by loss of liver fatty acid binding protein immunoexpression. In this study, we characterized the histopathologic spectrum of 13 liver fatty acid binding protein-deficient hepatocellular adenoma cases showing malignant transformation from multiple centers. Clinicopathologic characteristics of these patients were evaluated. Stains for reticulin, liver fatty acid binding protein, beta-catenin and glutamine synthetase were applied to these lesions. Moreover, the findings were compared to patients with ß-catenin mutated hepatocellular adenoma. Liver fatty acid binding protein-deficient hepatocellular adenomas with borderline features/carcinoma were seen predominantly in females (77%) with an average age of 46 ± 18 years and multiple lesions (77%; five patients with adenomatosis). Meanwhile, ß-catenin mutated hepatocellular adenoma patients with malignant transformation were predominantly male (67%, p = 0.018) with single lesion (86%, p = 0.0009). The largest liver fatty acid binding protein-deficient hepatocellular adenoma nodule in each patient ranged from 4 to 15.5 cm. Loss of liver fatty acid binding protein by immunohistochemistry was noted in all adenoma and borderline/carcinoma components. Features of malignant transformation were pseudoglandular architecture (85%), cytologic atypia (85%), architectural atypia (100%) and lack of steatosis (100%). Other findings included myxoid change (39%), peliosis (46%) and sinusoidal dilatation (46%). Molecular studies confirmed somatic inactivation of HNF1A in 3 cases and absence of TERT promotor and exon 3 CTNNB1 mutations in five cases. To summarize, liver fatty acid binding protein-deficient hepatocellular adenoma with malignant transformation is most frequently seen in female patients with multiple lesions. Most of these lesions demonstrate pseudoglandular architecture, cytologic and architectural atypia, with lack of steatosis. The natural history of these lesions is relatively benign with the exception of disease recurrence in 1 patient.

Identification of volumetric laser endomicroscopy features of colon polyps with histologic correlation.

BACKGROUND AND AIMS: There are limited data on the use of volumetric laser endomicroscopy (VLE) for imaging colon polyps. Our aim was to identify VLE features of colon polyps. METHODS: A total of 45 patients were included; 43 underwent endoscopic mucosal resection of colorectal polyps 2 cm or greater. These polyps were then scanned with VLE immediately after resection. Two patients who underwent partial colonic resection served as controls. RESULTS: Forty-three polyps were included with review of matching histology: 3 intramucosal cancer (IMCA), 5 tubular adenoma (TAs)/tubulovillous adenoma (TVA) with high-grade dysplasia (HGD), 9 TVA with only low-grade dysplasia (LGD), 5 serrated adenoma, and 21 TA with LGD. All TAs and TVAs were hyper-reflective compared with normal tissue. Effacement occurred in 82.4% (14/17) of the colonic polyps with advanced pathology (TVA with HGD/IMCA) compared with 11.6% (3/26) with non-advanced pathology (TA with LGD and serrated adenoma) (P < .0001). Forty-seven percent (8/17) of polyps with advanced pathology had greater than 5 glands on VLE compared with none in the non-advanced pathology group (P = .0001). An irregular surface mainly occurred in polyps with high-grade pathology (HGD/IMCA) versus TAs. Eighty-eight percent of polyps with HGD/IMC had an irregular surface (7/8) versus 6% (2/35) of TAs (P < .0001). CONCLUSIONS: In this ex vivo clinicopathologic study, we show that there are distinct VLE features of colon polyps that may help identify polyps or features of a higher-grade lesion. This may have implications for possible in vivo application to aid in dysplasia or polyp detection.

Optogenetic stimulation of the brainstem dorsal motor nucleus ameliorates acute pancreatitis.

Introduction: Inflammation is an inherently self-amplifying process, resulting in progressive tissue damage when unresolved. A brake on this positive feedback system is provided by the nervous system which has evolved to detect inflammatory signals and respond by activating anti-inflammatory processes, including the cholinergic anti-inflammatory pathway mediated by the vagus nerve. Acute pancreatitis, a common and serious condition without effective therapy, develops when acinar cell injury activates intrapancreatic inflammation. Prior study has shown that electrical stimulation of the carotid sheath, which contains the vagus nerve, boosts the endogenous anti-inflammatory response and ameliorates acute pancreatitis, but it remains unknown whether these anti-inflammatory signals originate in the brain. Methods: Here, we used optogenetics to selectively activate efferent vagus nerve fibers originating in the brainstem dorsal motor nucleus of the vagus (DMN) and evaluated the effects on caerulein-induced pancreatitis. Results: Stimulation of the cholinergic neurons in the DMN significantly attenuates the severity of pancreatitis as indicated by reduced serum amylase, pancreatic cytokines, tissue damage, and edema. Either vagotomy or silencing cholinergic nicotinic receptor signaling by pre-administration of the antagonist mecamylamine abolishes the beneficial effects. Discussion: These results provide the first evidence that efferent vagus cholinergic neurons residing in the brainstem DMN can inhibit pancreatic inflammation and implicate the cholinergic anti-inflammatory pathway as a potential therapeutic target for acute pancreatitis.

Plasma cells in human pancreatic ductal adenocarcinoma secrete antibodies against self-antigens.

Intratumoral B cell responses are associated with more favorable clinical outcomes in human pancreatic ductal adenocarcinoma (PDAC). However, the antigens driving these B cell responses are largely unknown. We sought to discover these antigens by using single-cell RNA sequencing (scRNA-Seq) and immunoglobulin (Ig) sequencing of tumor-infiltrating immune cells from 7 primary PDAC samples. We identified activated T and B cell responses and evidence of germinal center reactions. Ig sequencing identified plasma cell (PC) clones expressing isotype-switched and hypermutated Igs, suggesting the occurrence of T cell-dependent B cell responses. We assessed the reactivity of 41 recombinant antibodies that represented the products of 235 PCs and 12 B cells toward multiple cell lines and PDAC tissues and observed frequent staining of intracellular self-antigens. Three of these antigens were identified: the filamentous actin (F-actin), the nucleic protein RuvB like AAA ATPase 2 (RUVBL2), and the mitochondrial protein heat shock protein family D (Hsp60) member 1 (HSPD1). Antibody titers against F-actin and HSPD1 were substantially elevated in the plasma of patients with PDAC compared with healthy donors. Thus, PCs in PDAC produce autoantibodies reacting with intracellular self-antigens, which may result from promotion of preexisting, autoreactive B cell responses. These observations indicate the chronic inflammatory microenvironment of PDAC can support the adaptive immune response.

Olaparib-Induced Immune-Mediated Liver Injury.

Immune-mediated drug-induced liver injury can be triggered by multiple classes of medications including immunotherapies. Olaparib is a first-in-class oral inhibitor of poly (adenosine diphosphate-ribose) polymerase (an enzyme involved in DNA replication and repair) that is approved as maintenance treatment in platinum-sensitive, epithelial ovarian, tubal, or primary peritoneal cancers with breast cancer 1/2 mutation. We report the first case in the United States of an acute and severe liver injury with associated jaundice and liver synthetic dysfunction secondary to olaparib. The liver injury was resolved with drug cessation and treatment with prednisone taper.

Patient-Derived Triple-Negative Breast Cancer Organoids Provide Robust Model Systems That Recapitulate Tumor Intrinsic Characteristics.

Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer with poor patient outcomes, highlighting the unmet clinical need for targeted therapies and better model systems. Here, we developed and comprehensively characterized a diverse biobank of normal and breast cancer patient-derived organoids (PDO) with a focus on TNBCs. PDOs recapitulated patient tumor intrinsic properties and a subset of PDOs can be propagated for long-term culture (LT-TNBC). Single cell profiling of PDOs identified cell types and gene candidates affiliated with different aspects of cancer progression. The LT-TNBC organoids exhibit signatures of aggressive MYC-driven, basal-like breast cancers and are largely comprised of luminal progenitor (LP)-like cells. The TNBC LP-like cells are distinct from normal LPs and exhibit hyperactivation of NOTCH and MYC signaling. Overall, this study validates TNBC PDOs as robust models for understanding breast cancer biology and progression, paving the way for personalized medicine and tailored treatment options. SIGNIFICANCE: A comprehensive analysis of patient-derived organoids of TNBC provides insights into cellular heterogeneity and mechanisms of tumorigenesis at the single-cell level.

Mesenteric Arteriovenous Dysplasia/Vasculopathy Mimicking Crohn's Disease: A Case Report.

Mesenteric arteriovenous vasculopathy (MAVD/V) is an extremely rare and poorly understood disease and its incidence is probably underestimated. It is an uncommon, non-inflammatory and non-atherosclerotic form of mesenteric vascular injury, first reported in 2016, with characteristic histopathologic evidence of fibromuscular dysplasia-like vascular changes. We present the case of a chronically ill 84-year-old female with a 5 year history of recurrent small bowel obstruction, who underwent segmental resection of the small bowel. Intraoperative examination showed bowel stricture with fibrosis, intraluminal pill fragments and creeping mesenteric adipose tissue clinically compatible with Crohn's disease. Histological examination showed acute and chronic mucosal injury characterized by crypt distortion, ulcerations with granulation tissue, pseudo-pyloric metaplasia, areas of fibrosis and serosal adhesions. Multiple blood vessels (including both veins and arteries) demonstrated wall hyalinization, elastic degeneration and non-atherosclerotic luminal occlusion. The pattern of the mucosal injury is, in this case, potentially a consequence of acute and chronic ischemic processes secondary to mesenteric arteriovenous vasculopathy.

A rare case of Polyarteritis Nodosa associated with autoimmune hepatitis: a case report.

BACKGROUND: Polyarteritis nodosa is a type of vasculitis affecting medium- and small-sized arteries that has been associated with hepatitis B but does not have an established relationship with autoimmune hepatitis. Here we report the case of an adult patient with autoimmune hepatitis who, shortly after diagnosis, developed life-threatening polyarteritis nodosa. CASE PRESENTATION: A 45-year-old woman was diagnosed with autoimmune hepatitis after initially presenting with a two-month history of fatigue, nausea, and anorexia and a three-week history of scleral icterus. Her liver biopsy showed mild portal fibrosis and her liver chemistries improved with prednisone and azathioprine. Three months later, she presented to the emergency department with fever, bilateral ankle pain, rash, oral ulcers, and poor vision. Physical examination was notable for erythema nodosum, anterior uveitis, retinal vasculitis, and frosted branch angiitis (frosted branch angiitis (a widespread florid translucent perivascular exudate). She subsequently developed repeated episodes of ischemic acute bowel necrosis that required multiple surgeries and extensive small bowel resections. Surgical pathology of the small bowel resection revealed ischemic necrosis, medium and small vessel vasculitis with microvascular thrombi consistent with polyarteritis nodosa. Azathioprine was discontinued and she was treated with pulse steroids followed by a prednisone taper, cyclophosphamide, and intravenous immune globulin with overall improvement in her symptomatology. Since her hospitalization, she has been maintained on low-dose prednisone and mycophenolate mofetil. CONCLUSIONS: In patients with recent diagnosis of autoimmune hepatitis, there should be a modest suspicion for concomitant polyarteritis nodosa if symptoms and signs of multisystem vasculitis develop.

Targeted peripheral focused ultrasound stimulation attenuates obesity-induced metabolic and inflammatory dysfunctions.

Obesity, a growing health concern, is associated with an increased risk of morbidity and mortality. Chronic low-grade inflammation is implicated in obesity-driven metabolic complications. Peripheral focused ultrasound stimulation (pFUS) is an emerging non-invasive technology that modulates inflammation. Here, we reasoned that focused ultrasound stimulation of the liver may alleviate obesity-related inflammation and other comorbidities. After 8 weeks on a high-fat high-carbohydrate "Western" diet, C57BL/6J mice were subjected to either sham stimulation or focused ultrasound stimulation at the porta hepatis. Daily liver-focused ultrasound stimulation for 8 weeks significantly decreased body weight, circulating lipids and mitigated dysregulation of adipokines. In addition, liver-focused ultrasound stimulation significantly reduced hepatic cytokine levels and leukocyte infiltration. Our findings demonstrate the efficacy of hepatic focused ultrasound for alleviating obesity and obesity-associated complications in mice. These findings suggest a previously unrecognized potential of hepatic focused ultrasound as a possible novel noninvasive approach in the context of obesity.

A clinicopathological and immunohistochemical study of clinically non-functioning pituitary adenomas: a single institutional experience.

BACKGROUND: Non-functioning pituitary adenomas (NFPA) are characterized by the lack of clinical syndrome as compared to functioning adenomas (FA) but not all functioning adenomas have clinical effects. Their exact incidence varies in different series. MATERIALS AND METHODS: This study was undertaken to analyze the hormonal profile of NFPA at the immunohistochemical level in the Indian population and to see if any differences exist from the earlier studies. Their biological aggressiveness was also studied by MIB-1 labeling index (MIB-! LI) and Epidermal Growth Factor Receptor (EGFR) expression. These parameters along with their clinical behavior were correlated with radiological features of invasiveness and size. RESULTS: Of the 151 pituitary adenomas diagnosed during a period of one and half years, 77 (51%) were NFPA with a male predominance. There was increase in the incidence of NFPA with increase in age. Immunopositivity for various hormones was observed in 64 (83%) cases, either singly or in various combinations. On the basis of immunohistochemistry, NFPA were classified into three subtypes; gonadotroph adenomas, silent adenomas, and null cell adenomas. Gonadotroph adenomas were the commonest subtype. In general, NFPA showed low MIB-1LI but invasive NFPA had LI on the higher side, however, this difference was not significant. We observed EGFR positivity in two cases only; therefore the tumorigenesis mechanism may be different in NFPA. CONCLUSION: Although non-functional at the clinical level immunohistochemistry showed reactivity for various hormones. If a battery of immunostains including seven hormones is studied, a significant number of cases are shifted to the functional group.

Brown Bowel Syndrome: A Multi-institutional Case Series.

Brown bowel syndrome (BBS) is a rare condition associated with vitamin E deficiency and defined by prominent lipofuscin deposition in the muscularis propria. Eight unique cases of BBS were identified: 5 men and 3 women (mean age=58.6 y). Pertinent comorbidities included bariatric surgery=2, malnourishment=2, Crohn=2, cystic fibrosis=1, alcohol and cocaine abuse=1, and prior small bowel resections=1. Presenting symptoms included abdominal pain=3, bleeding=1, nausea and vomiting=1, and nonresponsiveness=1. Imaging studies were often abnormal: thickened bowel wall=3 (1 with a mass), small bowel obstruction=2, and edematous and dilated bowel wall=2. Most specimens were surgical resections (n=7, autopsy=1): extended right colectomy=2, small bowel only=5 (terminal ileum=3, jejunum=2). Two specimens were grossly described as mahogany, and 1 case contained a perforation. Histologic sections of all cases showed finely granular, brown cytoplasmic pigment in smooth muscle cells on hematoxylin and eosin. This pigment was most conspicuous in the muscularis propria (small bowel>colon), and it was not identified in the mucosa. The pigment was reactive with Fontana-Masson, carbol lipofuscin, Periodic acid-Schiff, and Periodic acid-Schiff with diastase, and electron microscopy was compatible with lipofuscin. The mean clinical follow-up was 208 weeks: 1 patient died of complications of encephalitis, the others were alive and well. BBS is important to recognize because it is linked with malnutrition, specifically vitamin E deficiency, and it can (rarely) clinically simulate malignancy. The diagnosis is based on the identification of the lipofuscin pigment in the cytoplasm of smooth muscle cells, which is most easily seen in the muscularis propria of the small bowel.

Glioneuronal tumor with neuropil-like islands: a new entity.

Glioneuronal tumor with neuropil-like islands (GTNI) is a distinctive and rare tumor characterized by both glial and neuronal differentiation. However, unlike other mixed glioneuronal tumors, which are characterized by a favorable prognosis, this neoplasm has been found to be potentially aggressive. We report here a case arising in a 60-year old male patient who presented with seizures, forgetfulness and right-sided hemiparesis, due to a left frontal lobe tumor. Unlike most cases described in the literature, the present tumor was unique in its radiological appearance, which was cystic. On microscopic evaluation, the glial component was chiefly gemistocytic punctuated by neuropil-like islands. Strong nuclear immunolabeling of p53 and absence of 1p/19q deletion by fluorescence in situ hybridization assay were consistent with those in previous reports.

Lumbosacral Wilms' tumor as a component of immature teratoma associated with spinal dysraphism--a rare case and short literature review.

Occurrence of extrarenal Wilms' tumor, in the lumbosacral region, as such or as a component of immature teratoma is an extremely uncommon condition and this diagnosis is almost always postsurgical. We report a case of immature teratoma in the lumbosacral region which was composed of mature teratomatous components and Wilms' tumor as an immature component. This 20-day-old male child presented with a swelling over the lower back at birth. Imaging of the spine revealed spina bifida and tethered cord. Excision of soft tissue swelling and detethering of the cord was performed. This case represents the fourth reported case of lumbosacral Wilms' tumor as a component of immature teratoma associated with spinal dysraphism. We discuss possible mechanisms and clinical characteristics of extrarenal Wilms' tumor and present a short review of the literature.