Notch1-Hes1 signalling axis in the tumourigenesis of biliary neuroendocrine tumours

Protective Effects of Gastrodin Against Gentamicin-Induced Vestibular Damage by the Notch Signaling Pathway

PURPOSE

Gentamicin is a broad-spectrum antibiotic commonly used in clinical practice. However, the drug causes side effects of ototoxicity, leading to disruption in balance functionality. This study investigated the effect of gastrodin, a prominent compound present in Gastrodia, and the underlying mechanism on the development of gentamicin-induced vestibular dysfunction.

METHODS

Wild-type C57BL/6 mice were randomly assigned to three groups: control, gentamicin, and gentamicin + gastrodin groups. The extent of gentamicin-induced vestibular impairment was assessed through a series of tests including the swimming test, contact righting reflex test, and air-righting reflex. Alterations in vestibular hair cells were monitored through immunofluorescence assay, and cellular apoptosis was observed using TUNEL staining. The mRNA and protein expression of Notch1, Jagged1, and Hes1 was quantified through qRT-PCR, immunofluorescence, and western blot analyses.

RESULTS

Gentamicin treatment led to pronounced deficits in vestibular function and otolith organ hair cells in mice. Nevertheless, pretreatment with gastrodin significantly alleviated these impairments. Additionally, the Notch signaling pathway was activated by gentamicin in the utricle, contributing to a notable increase in the expression levels of apoptosis-associated proteins. By contrast, gastrodin treatment effectively suppressed the Notch signaling pathway, thereby mitigating the occurrence of apoptosis.

CONCLUSION

Collectively, these findings underscore the crucial role of gastrodin in safeguarding against gentamicin-induced vestibular dysfunction through the modulation of the Notch signaling pathway. This study suggests the potential of gastrodin as a promising therapeutic agent for preventing vestibular injuries.

Panic at the Bile Duct: How Intrahepatic Cholangiocytes Respond to Stress and Injury

In the liver, biliary epithelial cells (BECs) line intrahepatic bile ducts (IHBDs) and are primarily responsible for modifying and transporting hepatocyte-produced bile to the digestive tract. BECs comprise only 3% to 5% of the liver by cell number but are critical for maintaining choleresis through homeostasis and disease. To this end, BECs drive an extensive morphologic remodeling of the IHBD network termed ductular reaction (DR) in response to direct injury or injury to the hepatic parenchyma. BECs are also the target of a broad and heterogenous class of diseases termed cholangiopathies, which can present with phenotypes ranging from defective IHBD development in pediatric patients to progressive periductal fibrosis and cancer. DR is observed in many cholangiopathies, highlighting overlapping similarities between cell- and tissue-level responses by BECs across a spectrum of injury and disease. The following core set of cell biological BEC responses to stress and injury may moderate, initiate, or exacerbate liver pathophysiology in a context-dependent manner: cell death, proliferation, transdifferentiation, senescence, and acquisition of neuroendocrine phenotype. By reviewing how IHBDs respond to stress, this review seeks to highlight fundamental processes with potentially adaptive or maladaptive consequences. A deeper understanding of how these common responses contribute to DR and cholangiopathies may identify novel therapeutic targets in liver disease.

Gallbladder neuroendocrine carcinoma diagnosis, treatment and prognosis based on the SEER database: A literature review

BACKGROUND

Gallbladder neuroendocrine carcinoma (GB-NEC) has a low incidence rate; therefore, its clinical characteristics, diagnosis, treatment and prognosis are not well explored.

AIM

To review recent research and analyze corresponding data in the Surveillance Epidemiology and End Results (SEER) database.

METHODS

Data of GB-NEC (n = 287) and gallbladder adenocarcinoma (GB-ADC) (n = 19 484) patients from 1975 to 2016 were extracted from the SEER database. Survival analysis was performed using Kaplan–Meier and Cox proportional hazards regression. P < 0.05 was considered statistically significant. We also reviewed 108 studies retrieved from PubMed and Reference Citation Analysis (https://www.referencecitationanalysis.com/). The keywords used for the search were: "(Carcinoma, Neuroendocrine) AND (Gallbladder Neoplasms)".

RESULTS

The GB-NEC incidence rate was 1.6% (of all gallbladder carcinomas), male to female ratio was 1:2 and the median survival time was 7 mo. The 1-, 2-, 3- and 5-year overall survival (OS) was 36.6%, 17.8%, 13.2% and 7.3% respectively. Serum chromogranin A levels may be a specific tumor marker for the diagnosis of GB-NEC. Elevated carcinoembryonic antigen, carbohydrate antigen (CA)-19-9 and CA-125 levels were associated with poor prognosis. Age [hazard ratio (HR) = 1.027, 95% confidence interval (CI): 1.006–1.047, P = 0.01] and liver metastasis (HR = 3.055, 95% CI: 1.839–5.075, P < 0.001) are independent prognostic risk factors for OS. Patients with advanced GB-NEC treated with surgical resection combined with radiotherapy and/or chemotherapy may have a better prognosis than those treated with surgical resection alone. There was no significant difference in OS between GB-NEC and GB-ADC.

CONCLUSION

The clinical manifestations and prognosis of GB-NEC are similar to GB-ADC, but the treatment is completely different. Early diagnosis and treatment are the top priorities.

Neuroendocrine Neoplasms of the Female Genitourinary Tract: A Comprehensive Overview

Simple Summary

Primary neuroendocrine neoplasms (NENs) are a rare, heterogeneous group of tumors that include well-differentiated neuroendocrine tumors, poorly differentiated neuroendocrine carcinoma, and paraganglioma. NENs in the urinary tract are observed in <0.05% of individuals, in whom the bladder is the most common site. In this review, we described the epidemiology, pathogenesis, imaging, staging, and management of the genitourinary NENs.

Abstract

Primary neuroendocrine neoplasms are a rare heterogeneous group of tumors that include well-differentiated neuroendocrine tumors, poorly differentiated neuroendocrine carcinoma, and paraganglioma. An extensive literature search was used to compile the data regarding epidemiology, pathogenesis, imaging features, and management of the urinary system NENs. We also included the updated staging of the NENs at various locations of the urinary system.

A fat containing combined neuroendocrine carcinoma and hepatocellular carcinoma in the liver: A case report

A 79-year-old man was admitted to our hospital because of increased hepatobiliary enzyme levels. Dynamic computed tomography and magnetic resonance imaging showed a liver tumor measuring 60mm containing fat foci at the cranial aspect of the tumor. We diagnosed the patient with hypovascular hepatocellular carcinoma (HCC) and fat deposition, and performed a caudate lobe resection. Pathology examination revealed two intermingled components: moderately differentiated HCC with fat deposition and neuroendocrine carcinoma (NEC). Primary combined NEC and HCC is extremely rare. To our knowledge, this is the first report of combined NEC and HCC including a fat component. HCC is the most common primary hepatic malignancy with fat. HCC might include fat, even if HCC coexists with another type of cancer. The imaging characteristics of and HCC with another type of cancer vary depending on the amount of each component. We should not simply diagnose such tumors as HCC, but think about the possibilities of HCC with another type of cancer, because there is a fat component.

Propranolol Inhibits the Proliferation of Human Glioblastoma Cell Lines through Notch1 and Hes1 Signaling System

Objective

The anti-tumor effect of the beta-adrenergic receptor antagonist propranolol in breast cancer is well known; however, its activity in glioblastoma is not well-evaluated. The Notch-Hes pathway is known to regulate cell differentiation, proliferation, and apoptosis. We investigated the effect of propranolol to human glioblastoma cell lines, and the role of Notch and Hes signaling in this process.

Methods

We performed immunohistochemical staining on 31 surgically resected primary human glioblastoma tissues. We also used glioblastoma cell lines of U87-MG, LN229, and neuroblastoma cell line of SH-SY5Y in this study. The effect of propranolol and isoproterenol on cell proliferation was evaluated using the MTT assay (absorbance 570 nm). The impact of propranolol on gene expression (Notch and Hes) was evaluated using real-time polymerase chain reaction (RT-PCR, whereas protein levels of Notch1 and Hes1 were measured using Western blotting (WB), simultaneously. Small interfering RNA (siRNA) was used to suppress the Notch gene to investigate its role in the proliferation of glioblastoma.

Results

Propranolol and isoproterenol caused a dose-dependent decrease in cell proliferation (MTT assay). RT-PCR showed an increase in Notch1 and Hes1 expression by propranolol, whereas WB demonstrated increase in Notch1 protein, but a decrease in Hes1 by propranolol. The proliferation of U87-MG and LN229 was not significantly suppressed after transfection with Notch siRNA.

Conclusion

These results demonstrated that propranolol suppressed the proliferation of glioblastoma cell lines and neuroblastoma cell line, and Hes1 was more closely involved than Notch1 was in glioblastoma proliferation.

Clinicopathologic and Molecular Features of Mixed Neuroendocrine Non-Neuroendocrine Neoplasms of the Gallbladder

Neuroendocrine neoplasms of the gallbladder are rare, comprising 0.5% of all neuroendocrine cancers and about 2% of gallbladder cancers. These neoplasms can also be found along with other malignant neoplasms of epithelial origin, mostly adenocarcinomas. Herein, we describe an unusual finding of a three-component mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) of the gallbladder. We also review the literature on 29 similar cases and summarize key features. We report on a 62-year-old woman who presented with right upper quadrant pain with a positive Murphy’s sign. A clinical diagnosis of neoplasia was entertained and she underwent cholecystectomy. Gross examination of the specimen revealed a 5-cm exophytic mass at the gallbladder fundus. Histopathologic examination of the mass showed an infiltrating squamous cell carcinoma, an adjacent neuroendocrine carcinoma (each of these two components composed more than 30% of the neoplasm), and a superficial adenocarcinoma (composing 10% of the neoplasm). Gallbladder MiNENs present with similar symptoms and in the same age group as do carcinomas; however, their prognosis is often poor. Specific management and treatment guidelines have not been established since MiNENs are very rare.

Mixed adenoneuroendocrine carcinoma of the hepatic bile duct: a case report and review of the literature

Background

The World Health Organization's updated classification of digestive system neuroendocrine tumors in 2010 first proposed the classification of mixed adenoneuroendocrine carcinoma (MANEC). The incidence of biliary malignant tumors with neuroendocrine tumors accounts for less than 1% of all neuroendocrine tumors. Moreover, the incidence of hilar bile duct with MANEC is very rare.

Case presentation

A 65-year-old female patient came to our hospital for repeated abdominal pain for more than 4 months and skin sclera yellow staining for 1 week. Contrast-enhanced computed tomography imaging and magnetic resonance results suggested a hilar tumor for Bismuth-Corlette Type II. The patient underwent radical surgery for hilar cholangiocarcinoma. Finally, the patient was diagnosed with hilar bile duct MANEC, staged 1 (pT1N0M0) based on the eighth edition of the AJCC. Histopathology showed that the tumor was a biliary tumor with both adenocarcinoma and neuroendocrine carcinoma. No evidence of recurrence and metastasis after 20 months of follow-up.

Conclusions

We first reported a MANEC that originated in the hilar bile duct. As far as we known, there were few reports of biliary MANEC, and the overall prognosis was poor. We also found that the higher the Ki-67 index, the worse the prognosis of this type of patient. Radical surgery is the most effective treatment.

Expression of fatty-acid-binding protein 5 in intrahepatic and extrahepatic cholangiocarcinoma: the possibility of different energy metabolisms in anatomical location

The biliary tract cancer (BTC) covers a range of carcinomas, including intrahepatic cholangiocarcinoma (ICC), cholangiolocellular carcinoma (CoCC), perihilar cholangiocarcinoma (perihilar CC), extrahepatic cholangiocarcinoma (ECC), and gallbladder cancer (GBC), defined according to the anatomical location. These adenocarcinomas mostly comprise biliary epithelial cell-derived malignant cells. In addition to anatomical differences, there are morphological and biological differences in BTC starting from embryonic development of the tissues extending to physiological differences. Fatty acid-binding proteins (FABPs) are closely associated with the energy metabolism. Using surgical specimens from 74 BTCs, we performed immunohistochemistry for FABP5 and its associated molecules, including peroxisome proliferator-activated receptor γ (PPARγ), PPARγ coactivator 1 (PGC-1), and estrogen-related receptor α (ERRα). We found that the expression patterns of small BTCs (ICC and CoCC) considerably differed from those of large BTCs (perihilar CC, ECC, and GBC). Expression of FABP5 and PGC-1 in large BTCs was high compared with those of small BTCs, but no difference in the expression of PPARγ and ERRα was observed. FABP5 appears to play a role in malignant progression in large BTCs. Small and large BTCs possess different energy metabolism systems owing to their different anatomical locations and course of carcinogenesis, although all BTCs originate from biliary epithelial cells.

Updates on the Role of Molecular Alterations and NOTCH Signalling in the Development of Neuroendocrine Neoplasms

Neuroendocrine neoplasms (NENs) comprise a heterogeneous group of rare malignancies, mainly originating from hormone-secreting cells, which are widespread in human tissues. The identification of mutations in ATRX/DAXX genes in sporadic NENs, as well as the high burden of mutations scattered throughout the multiple endocrine neoplasia type 1 (MEN-1) gene in both sporadic and inherited syndromes, provided new insights into the molecular biology of tumour development. Other molecular mechanisms, such as the NOTCH signalling pathway, have shown to play an important role in the pathogenesis of NENs. NOTCH receptors are expressed on neuroendocrine cells and generally act as tumour suppressor proteins, but in some contexts can function as oncogenes. The biological heterogeneity of NENs suggests that to fully understand the role and the potential therapeutic implications of gene mutations and NOTCH signalling in NENs, a comprehensive analysis of genetic alterations, NOTCH expression patterns and their potential role across all NEN subtypes is required.

Mixed adenoendocrine carcinoma in the extrahepatic biliary tract: A case report and literature review

Neuroendocrine neoplasm (NEN) comprises a group of tumors that exhibit neuroendocrine phenotypes. NEN is subclassified into neuroendocrine tumor (NET), neuroendocrine carcinoma (NEC) and mixed adenoendocrine carcinoma (MANEC), based on histopathological parameters. NEN in the extrahepatic biliary tract (EHBT) is uncommon. Little is known about its clinicopathological features and prognostic indicators. The present study presented a case of MANEC in the distal common bile duct (CBD) and reviewed previous cases of NENs in the EHBT to characterize the clinical settings of this disease entity and to identify influencing factors of survival outcomes. A 64-year-old Chinese woman presented with abdominal pain and jaundice. Imaging studies demonstrated malignant stenosis in the distal CBD. Bile duct brush cytology revealed small clusters of atypical cells. Following an initial diagnosis of distal cholangiocarcinoma (CCA), the patient underwent pancreaticoduodenectomy. Histological analysis combined with immunohistochemical investigation of the resected specimen revealed a collision tumor that was composed of poorly differentiated adenocarcinoma and NEC. Each histological component accounted for >30% of the tumor. The definitive diagnosis was a MANEC in the distal CBD. Multiple intrahepatic and pulmonary metastases were observed postoperatively over 8 months. The patient succumbed to the disease 12 months after surgery. In conclusion, NEN occurs infrequently in the EHBT, with NET being the predominant type. NEN in the EHBT is extremely challenging to diagnose preoperatively due to its tendency to mimic CCA. Patients with NEN in the EHBT exhibited extremely distinct oncology outcomes according to pathological types. Additionally, old age (>60 years) and the presence of tumor recurrence were associated with decreased survival of patients with NEN.

Primary large-cell neuroendocrine carcinoma of the upper ureter: A case report

RATIONALE

The incidence of primary large-cell neuroendocrine carcinoma (LCNEC) is extremely rare in the urinary tract. In the present study, we investigated a case of primary LCNEC associated with the upper ureter.

PATIENT CONCERN

A 58-year-old Korean female patient with right ureter mass, which was accidentally detected. An enhancing mass measuring 3.3 cm in size was found in the computed tomography (CT) scan. No definitive evidence of lymph node and distant metastasis was observed.

DIAGNOSIS

Histopathological analysis revealed large atypical epithelial cells in upper ureter mass, based on neuroendocrine morphology. Immunohistochemistry was positive for synaptophysin, CD 56, and cytokeratin. Accordingly, the upper ureter mass was finally diagnosed as LCNEC stage III, pT3 cN0 cM0.

INTERVENTION

Right nephroureterectomy was conducted.

OUTCOMES

Multiple metastatic lesions were detected in the right adrenal, paracaval, and right pararenal space of the patient in a CT scan 3 months post-surgery. The patient chemotherapy and radiation therapy were proceeded for metastatic and recurred mass. But patient died by multiorgan failure LESSONS:: In summary, this case study demonstrated that LCNEC can develop even in the upper ureter for the first time, despite the absence of neuroendocrine cells in the normal urothelium. The occurrence of LCNEC in the ureter is still very rare but is possible. Therefore, further studies are needed to establish appropriate treatment strategies.

Triptolide impairs thioredoxin system by suppressing Notch1-mediated PTEN/Akt/Txnip signaling in hepatocytes

Triptolide (TP) is the main ingredient of Chinese herb Tripterygium wilfordii Hook f. (TWHF). Despite of its multifunction in pharmaceutics, accumulating evidences showed that TP caused obvious hepatotoxicity in clinic. The current study investigated the role of Notch1 signaling in TP-induced hepatotoxicity. Our data indicated that TP inhibited the protein expression of Notch1 and its active form Notch intracellular domain (NICD) leading to increased PTEN (phosphatase and tensin homolog deleted on chromosome ten) expression. Moreover, PTEN triggered Txnip (thioredoxin-interacting protein) activation by inhibiting Akt phosphorylation, which resulted in reduction of Trx (thioredoxin). In conclusion, TP caused liver injury through initiating oxidative stress in hepatocyte. This study indicated the potency of Notch1 to protect against TP-induced hepatotoxicity.

Doxorubicin combined with Notch1-targeting siRNA for the treatment of gastric cancer

Notch1, a transmembrane receptor that has a notable role in gastric cancer (GC) as an oncogene, has been reported to be involved in doxorubicin resistance. Thus, Notch1 is a potential therapeutic target for GC. In the present study, the protein levels of Notch1 intracellular domain (NICD; a marker of Notch1 activation) in human GC cell lines and tumor tissues was measured by western blotting. Next, the effects of Notch1 depletion in SGC7901 cells were evaluated. Finally, the efficacy of Notch1 small interfering RNA (siRNA) combined with doxorubicin therapy for GC was examined in vitro and in vivo. The results revealed that NICD levels were high in GC cells, and that the inhibition of NICD by transfection with Notch1 siRNA induced apoptosis and inhibited proliferation. Ectopic downregulation of Notch1 expression enhanced the sensitivity of GC tumors to doxorubicin, which suppressed the development of GC. These data demonstrated that Notch1 was a significant regulator of cell proliferation and apoptosis in GC. Thus, the combination of doxorubicin with Notch1 siRNA is a potential strategy for the treatment of GC.

Unraveling molecular pathways of poorly differentiated neuroendocrine carcinomas of the gastroenteropancreatic system: A systematic review

BACKGROUND

Poorly differentiated neuroendocrine carcinomas (NECs) are rare and aggressive tumors. Their molecular pathogenesis is still largely unknown, and consequently, the best therapeutic management also remains to be determined. We conducted a systematic review on molecular alterations found in gastroenteropancreatic NECs (GEP-NECs) and discuss potential applications of targeted therapies in setting.

MATERIALS AND METHODS

Systematic review of studies about molecular features in tumor tissues of patients with GEP-NECs. The Medline, Lilacs, Embase, Cochrane, Scopus and Opengrey databases were sought, without time, study design or language restrictions.

RESULTS

Of the 1.564 studies retrieved, 41 were eligible: 33 were retrospective studies and eight were case reports. The studies spanned the years 1997-2017 and involved mostly colorectal, stomach and pancreas primary tumors. Molecular alterations in the TP53 gene and the p53 protein expression were the most commonly observed, regardless of the primary site. Other consistently found molecular alterations were microsatellite instability (MSI) in approximately 10% of gastric and colorectal NEC, and altered signaling cascades of p16/Rb/cyclin D1, Hedgehog and Notch pathways, and somatic mutations in KRAS, BRAF, RB1 and Bcl2. In studies of mixed adeno-neuroendocrine carcinomas (MANECs) the molecular features of GEP-NEC largely resemble their carcinoma/adenocarcinomas tumor counterparts.

CONCLUSIONS

Despite the paucity of data about the molecular drivers associated with GEP-NEC, some alterations may be potentially targeted with new cancer-directed therapies. Collaborative clinical trials for patients with advanced GEP-NEC are urgently needed.

Primary Biliary Mixed Adenoneuroendocrine Carcinoma (MANEC): A Short Review

Mixed adenoneuroendocrine carcinomas (MANECs) are composite neoplasms with areas of adenocarcinoma or squamous cell carcinoma intermingled with neuroendocrine carcinoma or neuroendocrine tumor, each composing at least 30% of the neoplasm. MANECs are very infrequent overall, and they are more commonly diagnosed in the appendix, colon, and stomach. Biliary MANECs are particularly rare, and their histogenesis is debated because neuroendocrine cells are seldom identified in the normal biliary tract. They can show one of the 3 different architectural patterns described in Lewin's original classification: collision tumors, combined lesions, or amphicrine neoplasms. The neuroendocrine component is usually of a high grade, with small or large cell cytomorphology, whereas the adenocarcinoma component is either an intestinal or biliary type. Clinical presentation is characterized by locally advanced disease at the time of initial diagnosis. Recent studies suggest that treatment should be guided by the most aggressive histologic component.

Primary Neuroendocrine Tumors of the Ureter: A Short Review

Neuroendocrine tumors represent 0.05% of urinary tract malignancies, and most originate in the bladder. Their pathogenesis is debated, since ureters are thought to lack neuroendocrine cells. Morphologically, most ureteral neuroendocrine tumors demonstrate the typical small cell neuroendocrine appearance, are immunohistochemically positive for synaptophysin/chromogranin A/CD56, and show electron-dense granules by electron microscopy. Clinical presentation is similar to that of other more common ureteral neoplasms. Prognosis is usually dismal, but a multimodal treatment approach including platinum-based adjuvant or neoadjuvant chemotherapy seems to be beneficial.

Clinicopathological features of neoplasms with neuroendocrine differentiation occurring in the liver

BACKGROUND/AIMS

We investigated the clinicopathological features of hepatic neuroendocrine tumours (NET) and neuroendocrine carcinoma (NEC), which remain largely unknown.

MATERIAL AND METHODS

We examined 1235 tumours from 1048 patients who had undergone curative hepatectomy for liver neoplasms at Kurume University Hospital. Pathological diagnoses were based on the 2010 WHO Classification of Tumours of the Digestive System. We performed immunostaining for hepatocyte markers (eg, hepatocyte paraffin (HepPar)-1), neuroendocrine markers (eg, chromogranin A (CGA)) and the proliferation marker (Ki-67).

RESULTS

There were four cases of NET G2 (0.38%) and five of hepatic malignant tumours with an NEC component (HNEC) (0.48%). HNEC cases were classified into three types, that is, transitional, intermediate and separate types, according to their histological and immunohistochemical features. In the former two types, the NEC component intermingled with the moderately to poorly differentiated hepatocellular carcinoma (HCC) component or intermediate component consisting of tumour cells showing the colocalisation of CGA and HepPar-1. In the separate type, the NEC and poorly differentiated HCC components were present separately, whereas the sarcomatous HCC component was detected in the vicinity of the NEC component. Ki-67 labelling indices of the NET G2, HCC and NEC components of HNEC were 6.8%, 14.9% and 58.9%, respectively.

CONCLUSIONS

Primary hepatic NET and NEC are very rare tumours. The NEC component in HNEC showed high proliferative activity and influenced patient prognoses.

Neuroendocrine Tumor of the Ureter: A Zebra Among Horses

Primary neuroendocrine tumors of the upper urinary tract are extremely rare. We report a case of de novo small cell carcinoma of the ureter that presented masquerading as a distal ureteral stone. A 55-year-old lady presented to our clinic with 1 month history of right lower back pain and hematuria. Her history was notable for stage 1B mixed clear cell-endometroid cancer of the uterus status post radical abdominal hysterectomy with adjuvant radiotherapy, 7 years before the current episode. The patient had no evidence of recurrence. Initial noncontrast imaging suggested a 2.5 mm calculus in the distal right ureter and hydronephrosis; however, ureteroscopy revealed a large fleshy mass at the location. Histopathologic evaluation demonstrated the lesion to be primary small cell carcinoma of the ureter, without evidence of it being a derivative of the prior gynecologic malignancy. Metastatic work-up revealed high burden retroperitoneal adenopathy. The patient was started on Cisplatin-based neoadjuvant chemotherapy with plan for nephroureterectomy in the future. At 3 months follow-up, the patient was doing well with significant shrinkage of retroperitoneal adenopathy and no evidence of disease progression.

Hes1 promotes cell proliferation and migration by activating Bmi-1 and PTEN/Akt/GSK3β pathway in human colon cancer

Hes1 is a transcription factor that influences cell proliferation and differentiation. However, the effect of Hes1 on invasiveness and the underlying mechanism remain unknown. In the current study, we found that Hes1 suppressed cell apoptosis, promoted cell growth, induced EMT phenotype and cytoskeleton reconstruction, and enhanced the metastatic potential of colon cancer cells in vitro and in vivo. Furthermore, we indicated that Bmi-1 mediated Hes1-induced cell proliferation and migration, downregulated PTEN and activated the Akt/GSK3β pathway, consequently induced EMT and cytoskeleton reconstruction, ultimately leading to enhanced invasiveness of cancer cells. In addition, we also found that both Hes1 and Bmi-1 could directly regulate PTEN by associating at the PTEN locus, and played important roles in regulating PTEN/Akt/GSK3β pathway. Our results provide functional and mechanistic links between Hes1 and Bmi-1/PTEN/Akt/GSK3β signaling in the development and progression of colon cancer.

Primary Ureteral Thyroid Transcription Factor 1-Positive Small Cell Neuroendocrine Carcinoma: Case Report and Review of the Literature

Upper urinary tract neoplasms comprise only 5% of urinary malignancies overall, the overwhelming majority showing an urothelial histology. Nonurothelial lesions represent 1.9% of upper tract neoplasms, and small cell carcinomas (SmCCs) only account for a minute fraction of them, with few cases reported in the literature to date. In the genitourinary tract, these lesions are most frequently found in the urinary bladder, where they tend to show a mixed histology with a characteristic small cell neuroendocrine component that is positive for chromogranin A, synaptophysin, and CD56 immunostains. Urinary SmCCs are almost invariably aggressive, with a propensity to infiltrate surrounding tissues and vascular structures. Unfortunately, clinical stage at presentation is often advanced, with early dissemination to lymph nodes or distant organs in a significant proportion of patients. For the most part, prognosis is dismal and can be predicted by the pathologic stage at diagnosis. Recently, new chemotherapeutic regimens have shown some potential benefit for the treatment of urinary SmCC, albeit not achieving curative results. Here we present the case of a 71-year-old male patient with a history of treated bladder urothelial carcinoma that presented with subacute flank pain and was diagnosed with a primary pure SmCC of the ureter. Besides the usual neuroendocrine immunomarkers, this tumor showed intense positivity for TTF-1 (thyroid transcription factor-1), a phenomenon that has been described for extrapulmonary SmCC of other locations.

Primary Mixed Adenoneuroendocrine Carcinoma of the Gallbladder in a 55-Year-Old Female Patient: A Case Report and Review of the Literature

Mixed adenoneuroendocrine carcinomas (MANECs) of the biliary tract are rare tumors, and to date only a few cases arising in the gallbladder have been reported. Their histogenesis is a matter of debate, since the biliary tract normally lacks neuroendocrine cells. However, the immunohistochemical identification of nonneoplastic neuroendocrine cells in both biliary adenocarcinomas and intestinal metaplasia has been documented. Here we report a case of a 55-year-old female patient presenting with right upper quadrant pain, cholelithiasis, and a gallbladder mass identified after cholecystectomy. The histopathologic examination showed a MANEC, composed of an intestinal-type adenocarcinoma and a large cell neuroendocrine carcinoma, arising in a background of enteric metaplasia with extensive high-grade dysplasia. Moreover, we report the presence of focal pancreatic intraepithelial neoplasia-like epithelial lesions, which has not been described for these tumors yet. The histopathologic features of this case provide further support for the theory that MANECs arise following a metaplasia-dysplasia-carcinoma pathway.

Hes1, a Notch signaling downstream target, regulates adult hippocampal neurogenesis following traumatic brain injury

Hairy and enhancer of split 1 (Hes1), a downstream target of Notch signaling, has long been recognized as crucial in inhibiting neuronal differentiation. However, the role of Hes1 following traumatic brain injury (TBI) in adult neurogenesis in the mouse dentate gyrus (DG) remains partially understood. Here, we investigate the role of Hes1 in regulating neurogenesis in the DG of the adult hippocampus after TBI by up- or downregulating Hes1 expression. First, adenovirus-mediated gene transfection was employed to upregulate Hes1 in vivo. The mice were then subjected to TBI, and the hippocampal tissue was collected for Western blot analysis at designated times, pre- and post-injury. Moreover, the brain slices were stained for BrdU and doublecortin (DCX). We show that enhancing Hes1 inhibits the proliferation and differentiation of neural precursor cells (NPCs) in the DG of the hippocampus soon after TBI. Second, downregulation of Hes1 via RNA interference (RNAi) results in a significant increase in neuronal production and promotes the differentiation of NPCs into mature neurons in the DG, as assessed by BrdU and NeuN double staining. Furthermore, a Morris water maze (MWM) test clearly confirmed that the knockdown of Hes1 improves the spatial learning and memory capacity of adult mice following injury. Taken together, these observations suggest that Hes1 represents a negative regulator of adult neurogenesis post-TBI and that the precise space-time regulation of Hes1 expression in the DG may promote the recovery of neural function following TBI.

Hes1 is involved in the self-renewal and tumourigenicity of stem-like cancer cells in colon cancer

A small subpopulation of cancer cells with stem cell-like features might be responsible for tumour generation, progression, and chemoresistance. Hes1 influences the maintenance of certain stem cells and progenitor cells and the digestive systems. We found upregulated Hes1 in poorly differentiated cancer samples compared with well-differentiated tumour samples, and most of the adenocarcinomas exhibited significantly higher levels of Hes1 mRNA compared with that observed in matched normal colon samples. Moreover, Hes1 expression was found to be correlated with the expression of stem cell markers in colon cancer samples, and Hes1 upregulates the expression of stemness-related genes in colon cancer cells. In addition, Hes1 enhances the self-renewal properties of the stem-like cells by increasing the sizes of CD133+ cells and SP cells and the ability of tumour sphere formation. Additionally, the Hes1-overexpressing cells formed significantly larger and higher number of colonies, as determined through the colony and the soft agar assays. More importantly, Hes1 enhances the tumourigenicity of colon cancer cell lines in nude mice and exhibits a strong tumour-formation ability at a cell density of 1 × 10(3). Taken together, our data indicate that Hes1 induces stem-like cell self-renewal and increases the number of tumour-initiating cells in colon cancer.

Pancreatic metastasis from mixed adenoneuroendocrine carcinoma of the uterine cervix: a case report

Metastatic cancers of the pancreas are rare, accounting for approximately 2-4% of all pancreatic malignancies. Renal cell carcinoma is the most common solid tumor that metastasizes to the pancreas. Here, we present a case of uterine cervical carcinoma metastasizing to the pancreas and review the literature regarding this rare event. A 44-year-old woman with a uterine cervical tumor had undergone radical hysterectomy and had been diagnosed pathologically with stage Ib mixed adenoneuroendocrine carcinoma in 2004. She underwent concurrent radiotherapy and chemotherapy postoperatively. Pulmonary metastases subsequently appeared in 2008 and 2011, and she underwent complete resection of the lung tumors by video-assisted thoracic surgery. Although she was followed up without any treatment and with no other recurrences, positron emission tomography revealed an area of abnormal uptake within the pancreatic body in 2012. Enhanced computed tomography demonstrated a 20-mm lesion in the pancreatic body and upstream pancreatic duct dilatation. Endoscopic ultrasonography-guided fine needle aspiration was performed and pathological examination suggested neuroendocrine carcinoma (NEC). On the basis of these results and the patient's oncological background, lesions in the pancreatic body were diagnosed as secondary metastasis from the cervical carcinoma that had been treated 8 years earlier. No other distant metastases were visualized, and the patient subsequently underwent middle pancreatectomy. Pathological examination showed NEC consistent with pancreatic metastasis from the uterine cervical carcinoma. The patient has survived 7 months since the middle pancreatectomy without any signs of local recurrence or other metastatic lesions.