Notch Signaling Pathway Expression in the Skin of Leprosy Patients: Association With Skin and Neural Damage.

Introduction: Leprosy is an infectious disease caused by Mycobacterium leprae, a debilitating disease that affects the skin and peripheral nerves. It is possible that tissue changes during infection with leprosy are related to alterations in the activity of the Notch signaling pathway, an innate signaling pathway in the physiology of the skin and peripheral nerves. Methods: This is a descriptive observational study. Thirty skin biopsies from leprosy patients and 15 from individuals with no history of this disease were evaluated. In these samples, gene expressions of cellular components associated with the Notch signaling pathway, Hes-1, Hey-1, Runx-1 Jagged-1, Notch-1, and Numb, were evaluated using q-PCR, and protein expression was evaluated using immunohistochemistry of Runx-1 and Hes-1. Results: Changes were observed in the transcription of Notch signaling pathway components; Hes-1 was downregulated and Runx-1 upregulated in the skin of infected patients. These results were confirmed by immunohistochemistry, where reduction of Hes-1 expression was found in the epidermis, eccrine glands, and hair follicles. Increased expression of Runx-1 was found in inflammatory cells in the dermis of infected patients; however, it is not related to tissue changes. With these results, a multivariate analysis was performed to determine the causes of transcription factor Hes-1 reduction. It was concluded that tissue inflammation was the main cause. Conclusions: The tissue changes found in the skin of infected patients could be associated with a reduction in the expression of Hes-1, a situation that would promote the survival and proliferation of M. leprae in this tissue.

Modelling human hepato-biliary-pancreatic organogenesis from the foregut-midgut boundary.

Organogenesis is a complex and interconnected process that is orchestrated by multiple boundary tissue interactions1-7. However, it remains unclear how individual, neighbouring components coordinate to establish an integral multi-organ structure. Here we report the continuous patterning and dynamic morphogenesis of hepatic, biliary and pancreatic structures, invaginating from a three-dimensional culture of human pluripotent stem cells. The boundary interactions between anterior and posterior gut spheroids differentiated from human pluripotent stem cells enables retinoic acid-dependent emergence of hepato-biliary-pancreatic organ domains specified at the foregut-midgut boundary organoids in the absence of extrinsic factors. Whereas transplant-derived tissues are dominated by midgut derivatives, long-term-cultured microdissected hepato-biliary-pancreatic organoids develop into segregated multi-organ anlages, which then recapitulate early morphogenetic events including the invagination and branching of three different and interconnected organ structures, reminiscent of tissues derived from mouse explanted foregut-midgut culture. Mis-segregation of multi-organ domains caused by a genetic mutation in HES1 abolishes the biliary specification potential in culture, as seen in vivo8,9. In sum, we demonstrate that the experimental multi-organ integrated model can be established by the juxtapositioning of foregut and midgut tissues, and potentially serves as a tractable, manipulatable and easily accessible model for the study of complex human endoderm organogenesis.

LncRNA SNHG1 promotes cell proliferation in laryngeal cancer via Notch1 signaling pathway.

OBJECTIVE: We aimed at elucidating the potential function of long noncoding ribonucleic acids (lncRNAs) small nucleolar RNA host gene 1 (SNHG1) in the progression of laryngeal cancer (LC) and its underlying mechanism. PATIENTS AND METHODS: Relative level of SNHG1 in LC tissues and controls was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Its expression in LC patients with different tumor stages and statues of lymph node metastasis was examined as well. Correlation between SNHG1 expression and prognosis of LC patients was evaluated by the Kaplan-Meier method. SNHG1 siRNA (si-SNHG1) was constructed for downregulation of SNHG1 expression. Potential effects of downregulated SNHG1 on viability and proliferation of LC cells were detected by cell counting kit-8 (CCK-8) and colony formation assay, respectively. After knockdown of SNHG1, relative levels of Notch1 and hairy, and enhancer of split homolog-1 (Hes1) were determined by qRT-PCR and Western blot. Regulatory effects of SNHG1/Notch1 axis on biological behaviors of LC were finally evaluated. RESULTS: SNHG1 was upregulated in LC tissues than that of controls. Besides, its level was higher in LC with T3-T4 relative to those of T1-T2. Higher abundance of SNHG1 was identified in LC patients with lymph node metastasis compared with those non-metastatic patients. Survival analysis indicated that LC patients with high-level SNHG1 had worse overall survival. Knockdown of SNHG1 in Tu212 and Hep2 cells downregulated relative levels of Notch1 and Hes1. Moreover, SNHG1 knockdown resulted in decreased viability and proliferative ability of LC cells. Notch1 overexpression could reverse the regulatory effects of SNHG1 on viability and proliferation of LC cells. CONCLUSIONS: LncRNA SNHG1 is highly expressed in LC tissues. It promotes the proliferation of LC cells by inhibiting Notch1 pathway, thereby promoting the progression of LC.

Uniform and Robust Nuclear Expression of HES1 in Neuroendocrine Neoplasms.

Introduction. Neuroendocrine neoplasms (NENs) are neoplasms that most commonly arise from gastrointestinal tract, pancreas, and lung. HES1 is a downstream target of Notch signaling pathway. The current literature about HES1 expression in NENs is sparse and inconsistent. Methods. In this study, we evaluated HES1 expression by immunohistochemistry in a total of 32 cases of NENs, including 13 well-differentiated neuroendocrine tumors from gastrointestinal tract, 10 cases of well-differentiated neuroendocrine tumors of pancreas, 9 cases from lung, including 4 cases of typical carcinoid, 1 case of atypical carcinoid, and 4 cases of neuroendocrine carcinoma. The intensity of the stain was scored from - to +++, and the distribution of the staining of HES1 was evaluated. Results. HES1 demonstrates uniform robust (+++) nuclear staining pattern in the tumor cells of all the NENs (32/32), regardless of the origin of the system and the grade of the tumor. Conclusions. HES1 is uniformly expressed in NENs with robust nuclear expression pattern. Our finding suggests that NOTCH1 or HES1 inhibitor is a potential therapeutic choice for neuroendocrine neoplasms.

[Xinfeng Capsule improves lung function by regulating Notch/Jagged-HES axis of type II alveolar epithelial cells in adjuvant arthritis rats].

Objective To observe the effect of Xinfeng Capsule (XFC) on Notch/Jagged-HES of type II alveolar epithelial cells (AECII). Methods Rats were divided for four groups: normal control (NC) group, model control (MC) group, leflunomide (LEF) group, XFC group, with 10 rats in each group. Complete Freund's adjuvant (CFA) was injected in the right foot plantar skin of each rat except for the NC group. After adjuvant arthritis was successfully induced, LEF group was given LEF (0.5 mg/100 g), and XFC group was treated with XFC (0.034 g/100 g), once a day from the 13th day to the 42th day. The NC and MC groups were given normal saline instead. Swelling degree (SD), arthritis index (AI) and pulmonary function were observed. AECII was observed by transmission electron microscopy (TEM). The expressions of transforming growth factor ß1 (TGF-ß1), Notch1, Notch3, Jagged1 and HES1 proteins in AECII were detected by Western blotting. Results The pulmonary function parameters such as forced expiratory volume in 1 second (FEV1), maximum expiratory flow rate at 50% FVC (FEF50), instantaneous flow at 75% of expired volume (FEF75), peak expiratory flow (PEF) in the MC group were significantly lower than those in the NC group, and the expressions of TGF-ß1, Notch1, Notch3, Jagged1 and HES1 in AECII increased. The ultrastructure of AECII was damaged. Compared with the MC group, FEV1, FEF50, FEF75 and PEF increased, and TGF-ß1, Notch1, Notch3, Jagged1 and HES1 decreased in the XFC group. Compared with LEF group, the lung function was better in XFC group. Conclusion XFC can inhibit pulmonary fibrosis and improve pulmonary function by down-regulating TGF-ß1, Notch1, Notch3, Jagged1 and HES1 in rats with adjuvant arthritis.

Fucosylation Deficiency in Mice Leads to Colitis and Adenocarcinoma.

BACKGROUND & AIMS: De novo synthesis of guanosine diphosphate (GDP)-fucose, a substrate for fucosylglycans, requires sequential reactions mediated by GDP-mannose 4,6-dehydratase (GMDS) and GDP-4-keto-6-deoxymannose 3,5-epimerase-4-reductase (FX or tissue specific transplantation antigen P35B [TSTA3]). GMDS deletions and mutations are found in 6%-13% of colorectal cancers; these mostly affect the ascending and transverse colon. We investigated whether a lack of fucosylation consequent to loss of GDP-fucose synthesis contributes to colon carcinogenesis. METHODS: FX deficiency and GMDS deletion produce the same biochemical phenotype of GDP-fucose deficiency. We studied a mouse model of fucosylation deficiency (Fx-/- mice) and mice with the full-length Fx gene (controls). Mice were placed on standard chow or fucose-containing diet (equivalent to a control fucosylglycan phenotype). Colon tissues were collected and analyzed histologically or by enzyme-linked immunosorbent assays to measure cytokine levels; T cells also were collected and analyzed. Fecal samples were analyzed by 16s ribosomal RNA sequencing. Mucosal barrier function was measured by uptake of fluorescent dextran. We transplanted bone marrow cells from Fx-/- or control mice (Ly5.2) into irradiated 8-week-old Fx-/- or control mice (Ly5.1). We performed immunohistochemical analyses for expression of Notch and the hes family bHLH transcription factor (HES1) in colon tissues from mice and a panel of 60 human colorectal cancer specimens (27 left-sided, 33 right-sided). RESULTS: Fx-/- mice developed colitis and serrated-like lesions. The intestinal pathology of Fx-/- mice was reversed by addition of fucose to the diet, which restored fucosylation via a salvage pathway. In the absence of fucosylation, dysplasia appeared and progressed to adenocarcinoma in up to 40% of mice, affecting mainly the right colon and cecum. Notch was not activated in Fx-/- mice fed standard chow, leading to decreased expression of its target Hes1. Fucosylation deficiency altered the composition of the fecal microbiota, reduced mucosal barrier function, and altered epithelial proliferation marked by Ki67. Fx-/- mice receiving control bone marrow cells had intestinal inflammation and dysplasia, and reduced expression of cytokines produced by cytotoxic T cells. Human sessile serrated adenomas and right-sided colorectal tumors with epigenetic loss of MutL homolog 1 (MLH1) had lost or had lower levels of HES1 than other colorectal tumor types or nontumor tissues. CONCLUSIONS: In mice, fucosylation deficiency leads to colitis and adenocarcinoma, loss of Notch activation, and down-regulation of Hes1. HES1 loss correlates with the development of human right-sided colorectal tumors with epigenetic loss of MLH1. These findings indicate that carcinogenesis in a subset of colon cancer is consequent to a molecular mechanism driven by fucosylation deficiency and/or HES1-loss.

Loss of Hes1 expression is associated with poor prognosis in colorectal adenocarcinoma.

Alterations in the Notch signaling pathway play a role in colorectal cancer (CRC). Hes1, a Notch-induced transcription factor, has recently been reported to show decreased expression by immunohistochemistry in sessile serrated adenomas. Variable staining patterns have been reported in tubular adenomas, and existing data on Hes1 expression in CRC are limited and inconsistent. We therefore sought to investigate the expression of Hes1 by immunohistochemistry in a large and well-characterized cohort of CRC patients to determine clinicopathological associations and prognostic significance. Immunohistochemistry for Hes1 was performed on 2775 consecutive CRCs in tissue microarray format. Hes1 expression was classified into 3 categories: absent, 1302 cases (46.9%); cytoplasmic staining only with loss of nuclear staining, 1002 cases (36.1%); and nuclear with or without cytoplasmic staining, 471 cases (17%). In univariate analysis, loss of nuclear expression of HES1 was significantly associated with older age, female sex, right-sided location, mucinous or medullary histology, higher histological grade, microsatellite instability, BRAFV600E mutation, and larger tumor size. Strong and statistically significant associations with female sex, right-sided location, BRAFV600E mutation, microsatellite instability, and larger size remained in multivariate analysis. Patients with loss of nuclear expression of Hes1 had a significantly worse all-cause 5-year survival in both univariate (P = .002) and multivariate (P = .009) analysis. We conclude that loss of nuclear expression of Hes1 occurs in 83% of CRCs when studied in tissue microarray format and is associated with female sex, right-sided location, BRAFV600E mutation, microsatellite instability, larger tumor size, and significantly worse survival.