Chromogranin Research Articles

AMPK/SIRT1 signaling through p38MAPK mediates Interleukin-6 induced neuroendocrine differentiation of LNCaP prostate cancer cells

Neuroendocrine Prostate Cancer (NEPC) is an aggressive form of androgen independent prostate cancer (AIPC), correlated with therapeutic resistance. Interleukin (IL)-6 promotes proliferation and neuroendocrine differentiation (NED) of androgen dependent LNCaP cells. We treated LNCaP cells with IL-6 and observed for in vitro NED of cells and also expression of NE markers βIII tubulin, neuron-specific enolase (NSE) and chromogranin A (ChA). Here we investigated the proteins and/or pathways involved in NED of LNCaP cells induced by IL-6 and characterized their role in NED of PCa cells. We found that the altered proteins modulated AMPK signaling pathway in NE cells. Remarkably, IL-6 induces NED of LNCaP cells through activation of AMPK and SIRT1 and also both of these are co-regulated while playing a predominant role in NED of LNCaP cells. Of the few requirements of AMPK-SIRT1 activation, increased eNOS is essential for NED by elevating Nitric oxide (NO) levels. Pleiotropic effects of NO ultimately regulate p38MAPK in IL-6 induced NED. Hence, IL-6 induced AMPK-SIRT1 activation eventually transfers its activation signals through p38MAPK for advancing NED of LNCaP cells. Moreover, inactivation of p38MAPK with specific inhibitor (SB203580) attenuated IL-6 induced NED of LNCaP cells. Therefore, IL-6 promotes NED of PCa cells via AMPK/SIRT1/p38MAPK signaling. Finally, targeting AMPK-SIRT1 or p38MAPK in androgen independent PC3 cells with neuroendocrine features reversed their neuroendocrine characteristics. Taken together these novel findings reveal that targeting p38MAPK mitigated NED of PCa cells, and thus it can be a favorable target to overcome progression of NEPC.

The Emerging Roles of Chromogranins and Derived Polypeptides in Atherosclerosis, Diabetes, and Coronary Heart Disease.

Chromogranin A (CgA), B (CgB), and C (CgC), the family members of the granin glycoproteins, are associated with diabetes. These proteins are abundantly expressed in neurons, endocrine, and neuroendocrine cells. They are also present in other areas of the body. Patients with diabetic retinopathy have higher levels of CgA, CgB, and CgC in the vitreous humor. In addition, type 1 diabetic patients have high CgA and low CgB levels in the circulating blood. Plasma CgA levels are increased in patients with hypertension, coronary heart disease, and heart failure. CgA is the precursor to several functional peptides, including catestatin, vasostatin-1, vasostatin-2, pancreastatin, chromofungin, and many others. Catestatin, vasostain-1, and vasostatin-2 suppress the expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in human vascular endothelial cells. Catestatin and vasostatin-1 suppress oxidized low-density lipoprotein-induced foam cell formation in human macrophages. Catestatin and vasostatin-2, but not vasostatin-1, suppress the proliferation and these three peptides suppress the migration in human vascular smooth muscles. Chronic infusion of catestatin, vasostatin-1, or vasostatin-2 suppresses the development of atherosclerosis of the aorta in apolipoprotein E-deficient mice. Catestatin, vasostatin-1, vasostatin-2, and chromofungin protect ischemia/reperfusion-induced myocardial dysfunction in rats. Since pancreastatin inhibits insulin secretion from pancreatic β-cells, and regulates glucose metabolism in liver and adipose tissues, pancreastatin inhibitor peptide-8 (PSTi8) improves insulin resistance and glucose homeostasis. Catestatin stimulates therapeutic angiogenesis in the mouse hind limb ischemia model. Gene therapy with secretoneurin, a CgC-derived peptide, stimulates postischemic neovascularization in apolipoprotein E-deficient mice and streptozotocin-induced diabetic mice, and improves diabetic neuropathy in db/db mice. Therefore, CgA is a biomarker for atherosclerosis, diabetes, hypertension, and coronary heart disease. CgA- and CgC--derived polypeptides provide the therapeutic target for atherosclerosis and ischemia-induced tissue damages. PSTi8 is useful in the treatment of diabetes.

Risk factors for progression of appendiceal neuroendocrine tumours: low-stage tumours

Appendiceal well-differentiated neuroendocrine tumours (NETs) are usually incidental and clinically benign. Several studies have reported different risk factors for nodal metastasis. The aim of this study was to investigate our appendiceal NETs (App-NETs) to determine the factors associated with malignant behaviour. For 120 App-NETs, we reviewed the clinical presentation and follow-up, including serum chromogranin A (CgA) levels, and compiled several microscopic variables. Pathological factors were compared with nodal status and time to biochemical recurrence (elevated serum CgA level) by the use of Cox regression. We also reviewed similar App-NET data in the Surveillance, Epidemiology, and End Results (SEER) Programme. Among our 120 cases, seven patients had positive lymph nodes, and nine developed subsequent elevation of CgA levels; none developed distant metastases or died of disease. Only three patients had grade 2 NETs; none had nodal disease, and one developed an elevated CgA level. Increasing tumour size was associated with an increased risk of nodal disease [odds ratio (OR) 4.99, P=0.0055). All seven node-positive cases were ≥13mm. Factors associated with elevated CgA levels included age (OR 1.04, P=0.041), pT4 disease (OR 10.22, P=0.033), and nodal disease (OR 24.0, P=0.012), but not size (OR 2.13, P=0.072). Of the 1492 reported App-NETs in the SEER database with data on tumour size, 137 (9%) were pN1; only five of these (4%) were coded as being <5mm. Small (<5mm) App-NETs that do not invade the serosa or mesoappendix appear to be overwhelmingly benign and low-grade, requiring neither Ki67 staining nor synoptic reporting. Given their indolent behaviour, different nomenclature or staging may be more appropriate for these NETs.

Pancreastatin mediated regulation of UCP-1 and energy expenditure in high fructose fed perimenopausal rats

AimsPancreastatin (PST) is a crucial bioactive peptide derived from chromogranin A (CHGA) proprotein that exhibits an anti-insulin effect on adipocytes. Herein, we investigated the effects of PST on brown adipose tissues (BAT) and white adipose tissue (WAT) in connection with uncoupling protein-1 (UCP-1) regulated energy expenditure in high fructose diet (HFrD) fed and vinylcyclohexenediepoxide (VCD) induced perimenopausal rats. Material and methodsWe administered VCD in rats for 17 consecutive days and fed HFrd for 12 weeks. After 12 weeks estradiol and progesterone levels were detected. Furthermore, detection of glucose tolerance, insulin sensitivity, and body composition revealed impaired glucose homeostasis and enhanced PST levels. Effects of enhanced PST on UCP-1 level in BAT and WAT of perimenopausal rats were further investigated. Key findingsReduced serum estradiol, progesterone, and attenuated insulin response confirmed perimenopausal model development. Furthermore, enhanced PST serum level and its increased expression in BAT and WAT downregulated the UCP-1 expression. Subsequently, impaired ATP level, NADP/NADPH ratio, citrate synthase activity, enhanced mitochondrial reactive oxygen species (ROS) generation and perturbed mitochondrial membrane potential, further exacerbated mitochondrial dysfunction, cellular ROS production, and promoted apoptosis. Interestingly, PST inhibition by PST inhibitor peptide-8 (PSTi8) displayed a favorable impact on UCP-1 and energy expenditure. SignificanceThe aforementioned outcomes indicated the substantial role of PST in altering the UCP-1 expression and associated energy homeostasis. Hence our results corroborate novel avenues to unravel the quest deciphering PST's role in energy homeostasis and its association with perimenopause.

Internalization and membrane activity of the antimicrobial peptide CGA-N12.

Antimicrobial peptides (AMPs) are conventional antibiotic alternatives due to their broad-spectrum antimicrobial activities and special mechanisms of action against pathogens. The antifungal peptide CGA-N12 was originally derived from human chromogranin A (CGA) and consists of the 65th to 76th amino acids of the CGA N-terminal region. In the present study, we found that CGA-N12 had fungicidal activity and exhibited time-dependent inhibition activity against Candida tropicalis. CGA-N12 entered the cells to exert its antagonist activity. The internalization of CGA-N12 was energy-dependent and accompanied by actin cytoskeleton-, clathrin-, sulfate proteoglycan-, endosome-, and lipid-depleting agent-mediated endocytosis. Moreover, the CGA-N12 internalization pathway was related to the peptide concentration. The effects of CGA-N12 on the cell membrane were investigated. CGA-N12 at a low concentration less than 4 × MIC100 did not destroy the cell membrane. While with increasing concentration, the damage to the cell membrane caused by CGA-N12 became more serious. At concentrations greater than 4 × MIC100, CGA-N12 destroyed the cell membrane integrity. Therefore, the membrane activity of CGA-N12 is concentration dependant.

Laparoscopic Surgery for Gallbladder Neuroendocrine Carcinoma: a Case Series and Literature Review

Gallbladder neuroendocrine carcinomas (GB-NECs) are a group of rare and heterogeneous neoplasms. There are few reports regarding laparoscopic surgery for GB-NEC cases diagnosed at advanced stage. Three patients, two females and one male, were admitted to our hospital. Two patients had the chief complaint of upper quadrant pain and one patient was found to have gallbladder occupation during a routine health checkup. No patient complained of jaundice, weight loss, or carcinoid syndrome–related symptoms including diarrhea, edema, flushing, and wheezing. Contrast-enhanced computed tomography (CT) examination showed local wall thickening of the gallbladder. In addition, one patient showed focal liver parenchymal invasion, and none of the three patients’ preoperative imaging examination revealed lymph node (LN) metastases. All three patients underwent laparoscopic radical cholecystectomy according to intraoperative frozen pathological examination, and they were diagnosed as GB-NEC based on postoperative pathology and immunohistochemistry. TNM stages of these patients were IIIA (T3N0M0), IIIB (T3N1M0), and IVB (T3N2M0), respectively. Chromogranin A (CgA) and synaptophysin (Syn) were positive in all cases. No patient encountered postoperative bleeding, bile leakage, abdominal abscess, gastrointestinal fistulas, or pulmonary complication. Two patients underwent postoperative chemotherapy with two cycles and seven cycles of etoposide plus cisplatin, respectively. Another patient did not receive postoperative chemotherapy due to his poor general condition. The overall survival time of the three patients was 4.6 months, 16.8 months, and 8.5 months, respectively. All three patients presented with liver and/or bile duct recurrence after surgery with a tumor-free survival time of 2.3 months, 3.3 months, and 3.0 months, respectively. Laparoscopic surgery may be considered a potential treatment for advanced GB-NEC in selected patients. However, further studies are needed to investigate the tumor-free survival benefit of laparoscopic surgery, and whether expanding the resection scope could reduce postoperative recurrence.

Subgroup analysis by Ki-67 and baseline CgA of the randomized, placebo-controlled phase 3 study of surufatinib in advanced well-differentiated pancreatic neuroendocrine tumors (SANET-p).

4111 Background: In the phase 3 SANET-p trial (NCT02589821), surufatinib significantly increased progression-free survival (PFS) compared with placebo in patients with progressive, well-differentiated (grade 1 or 2), advanced pancreatic neuroendocrine tumors (NETs). Here we report the relationship of Ki-67 and baseline Chromogranin A (CgA) on efficacy outcomes. Methods: A total of 172 patients with advanced pancreatic NETs were randomized to surufatinib or placebo in a 2:1 ratio. Investigator-assessed PFS and objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 were used for the analysis. The post-hoc subgroup analyses were performed on Ki-67 subcategory: &lt; 5% (n = 40 vs 21), 5-10% (n = 57 vs 31), &gt; 10% (n = 16 vs 7), and baseline CgA subcategory: ≤ 2 times of upper limit of normal (ULN) (n = 59 vs 31), &gt; 2 × ULN (n = 44 vs 24). Results: In the intent-to-treat population, surufatinib was superior to placebo, median PFS (mPFS) of 10.9 vs 3.7 months (mo) ( p = 0.0011), with a stratified hazard ratio (HR) of 0.491 (95% confidence interval [CI]: 0.319, 0.755). mPFS was statistically significantly longer in the surufatinib arm versus that in the placebo arm in subgroups of Ki-67 5-10% (11.0 vs 3.7 mo, HR = 0.33, p= 0.0002), Ki-67 &gt; 10% (11.1 vs 2.8 mo, HR = 0.04, p = 0.0003) and CgA &gt; 2 × ULN (11.0 vs 3.7 mo, HR = 0.36, p = 0.0036). There was numerical PFS improvement with surufatinib compared to placebo in subgroup of Ki-67 &lt; 5% (9.3 vs 5.6 mo, HR = 0.91, p = 0.8015) and CgA ≤ 2 × ULN (9.4 vs 3.7 mo, HR = 0.61, p = 0.0809). ORRs in the subgroups of Ki-67 &lt; 5%, 5-10%, and &gt; 10% with surufatinib were 15.8%, 24.0% and 12.5% respectively. There was only one partial response in the placebo arm (with Ki-67 &lt; 5%). ORRs in the subgroups of CgA ≤ 2 × ULN and &gt; 2 × ULN with surufatinib were 18.9% and 21.4%, while also only one partial response in the placebo arm with CgA ≤ 2 × ULN. Conclusions: Surufatinib showed statistically significant and clinically meaningful improvement in PFS compared to placebo in patients with advanced, progressive, well-differentiated pancreatic NETs. From this exploratory analysis, surufatinib demonstrated benefit irrespective of Ki-67 expression levels or baseline CgA. Clinical trial information: NCT02589821.

INSM1 Expression in Breast Neoplasms with Neuroedocrine Features

According to the 2019 WHO classification of breast tumors, neuroendocrine neoplasms (NENs) are classified into well-differentiated NE tumors (NET) and poorly differentiated NE carcinomas (NEC), while other breast cancers (BCs) of special and no special type with neuroendocrine (NE) features are not incorporated in this scheme anymore. We aimed to assess whether INSM1, a novel NE marker, could have a role in breast NEN subtyping. We selected 63 BCs operated from 2003 to 2018, classified as BCs with NE features, with available clinico-pathological data. Following 2019 WHO criteria, this cohort was reclassified into 37 NETs/NECs, the remaining 26 tumors representing solid-papillary (7), mucinous (7), and mixed type (12) carcinomas with NE differentiation. Chromogranin A (CGA) and synaptophysin (SYN) immunostains were reviewed, and INSM1 was tested by immunohistochemistry. Thirty CGA- and SYN-negative no special type BCs served as negative control. INSM1 was expressed in 52/63 cases of the whole cohort (82.54%). INSM1 positive and negative cases had no significantly different clinico-pathological characteristics. INSM1 expression was not significantly different between the newly reclassified NET/NEC group and other BCs with NE features. No immunoexpression was observed in control BCs. The sensitivity and specificity of INSM1 for the NE phenotype was 82.5% and 100%, respectively, compared to 61.9% and 100% for CGA, and 95.2 and 100% for SYN. In conclusion, INSM1 is as accurate as traditional NE biomarkers to identify NE differentiation in BC. In analogy to standard NE markers, INSM1 could not distinguish NET and NEC from the other BC histotypes with NE differentiation.

Effect of abiraterone combined with prednisone on serum CgA and NSE in metastatic castration-resistant prostate cancer without previous chemotherapy

Purpose: To investigate the influence of a combination of abiraterone and prednisone on serum chromogranin A (CgA) and neuron-specific enolase (NSE) in patients with metastatic castrationresistant prostate cancer (mCRPC) without previous chemotherapy, so as to provide reference data for drug therapy of prostate cancer.&#x0D; Methods: A total of 103 mCRPC patients without chemotherapy from January 2013 to March 2017 were included in this retrospective study. Seventy-one (71) patients received prednisone combined with abiraterone (study group), while 32 patients accepted prednisone (control group). The CgA, NSE and prostate-specific antigen (PSA) in the two groups were monitored, while PSA progression-free survival (PSA-PFS), radiographic PFS (rPFS), and overall survival (OS) were determined during follow-up.&#x0D; Results: PSA-PFS, rPFS and OS in the study group were significantly higher than those in the control group (p &lt; 0.05). The increased proportion of CgA or NSE in the study group was significantly lower than that in the control group at 6 months of treatment (p &lt; 0.05). The occurrences of NED before treatment and 6 months after treatment were both independent predictors of PSA and radiographic progression in the study group (p &lt; 0.05).&#x0D; Conclusion: The combination of prednisone and abiraterone is helpful for prognosis in mCRPC patients that are not on chemotherapy. The occurrence of NED predicts mostly poor prognosis of mCRPC patients on a combination of abiraterone and prednisone

Proteoglycan profiling of human, rat and mouse insulin-secreting cells.

Proteoglycans (PGs) are proteins with glycosaminoglycan (GAG) chains, such as chondroitin sulfate (CS) or heparan sulfate (HS), attached to serine residues. We have earlier shown that prohormones can carry CS, constituting a novel class of PGs. The mapping of GAG modifications of proteins in endocrine cells may thus assist us in delineating possible roles of PGs in endocrine cellular physiology. With this aim, we applied a glycoproteomic approach to identify PGs, their GAG chains and their attachment sites in insulin-secreting cells. Glycopeptides carrying GAG chains were enriched from human pancreatic islets, rat (INS-1 832/13) and mouse (MIN6, NIT-1) insulinoma cell lines by exchange chromatography, depolymerized with GAG lyases, and analyzed by nanoflow liquid chromatography tandem mass spectrometry. We identified CS modifications of chromogranin-A (CgA), islet amyloid polypeptide, secretogranin-1 and secretogranin-2, immunoglobulin superfamily member 10, and protein AMBP. Additionally, we identified two HS-modified prohormones (CgA and secretogranin-1), which was surprising, as prohormones are not typically regarded as HSPGs. For CgA, the glycosylation site carried either CS or HS, making it a so-called hybrid site. Additional HS sites were found on syndecan-1, syndecan-4, nerurexin-2, protein NDNF and testican-1. These results demonstrate that several prohormones, and other constituents of the insulin-secreting cells are PGs. Cell-targeted mapping of the GAG glycoproteome forms an important basis for better understanding of endocrine cellular physiology, and the novel CS and HS sites presented here provide important knowledge for future studies.

Serum Markers of Refractoriness and Enteropathy-Associated T-Cell Lymphoma in Coeliac Disease.

Simple SummaryCoeliac disease is a common chronic enteropathy that may lead to severe complications, including refractoriness (i.e., nonresponsiveness to a gluten-free diet) and enteropathy-associated T-cell lymphoma. In this study, we found that two serum markers, namely chromogranin A and β2-microglobuline, can predict these complications in patients with coeliac disease.The persistence or recurrence of symptoms in patients with coeliac disease (CD), despite a gluten-free diet (GFD), must prompt further work-up for excluding refractory CD (RCD). The aim of this study was to assess the accuracy of serum markers in predicting refractoriness in CD patients. This study included 72 patients affected by CD followed-up at our center, namely 49 uncomplicated CD before and after GFD and 23 RCD. Serum levels of chromogranin A (CgA) and β2-microglobuline were measured at baseline and at follow-up (median time of 13 months) in each group of patients. Cut-off points for each marker were estimated to differentiate RCD from uncomplicated CD patients. Serum levels of CgA and β2-microglobuline were significantly higher in patients with RCD compared to uncomplicated CD (p < 0.001), both at baseline and at follow-up, with no significant difference between RCD type 1 and type 2. The estimated cut-off point for CgA was 90.2 ng/mL (sensitivity 83%, specificity 100%), while for β2-microglobuline it was 696 mcg/L (sensitivity 100%, specificity of 100%). To conclude, CgA and β2-microglobuline could be useful serological markers of refractoriness in CD, with the ability to discriminate those patients who should undergo upper gastrointestinal endoscopy for making a definite diagnosis.

Chromogranin A regulates gut permeability via the antagonistic actions of its proteolytic peptides.

A "leaky" gut barrier has been implicated in the initiation and progression of a multitude of diseases, for example, inflammatory bowel disease (IBD), irritable bowel syndrome and celiac disease. Here we show how pro-hormone Chromogranin A (CgA), produced by the enteroendocrine cells, and Catestatin (CST: hCgA352-372 ), the most abundant CgA-derived proteolytic peptide, affect the gut barrier. Colon tissues from region-specific CST-knockout (CST-KO) mice, CgA-knockout (CgA-KO) and WT mice were analysed by immunohistochemistry, western blot, ultrastructural and flowcytometry studies. FITC-dextran assays were used to measure intestinal barrier function. Mice were supplemented with CST or CgA fragment pancreastatin (PST: CgA250-301 ). The microbial composition of cecum was determined. CgA and CST levels were measured in blood of IBD patients. Plasma levels of CST were elevated in IBD patients. CST-KO mice displayed (a) elongated tight, adherens junctions and desmosomes similar to IBD patients, (b) elevated expression of Claudin 2, and (c) gut inflammation. Plasma FITC-dextran measurements showed increased intestinal paracellular permeability in the CST-KO mice. This correlated with a higher ratio of Firmicutes to Bacteroidetes, a dysbiotic pattern commonly encountered in various diseases. Supplementation of CST-KO mice with recombinant CST restored paracellular permeability and reversed inflammation, whereas CgA-KO mice supplementation with CST and/or PST in CgA-KO mice showed that intestinal paracellular permeability is regulated by the antagonistic roles of these two peptides: CST reduces and PST increases permeability. The pro-hormone CgA regulates the intestinal paracellular permeability. CST is both necessary and sufficient to reduce permeability and primarily acts by antagonizing PST.

Smoothened loss is a characteristic of neuroendocrine prostate cancer.

PurposeHedgehog (Hh) signaling promotes castration‐resistant prostate cancer by supporting androgen‐independent prostate cancer cell development and growth; however, its role in neuroendocrine prostate cancer (NEPC) has not yet been explored. In this study, we assessed the expression of key genes involved in Hh signaling in prostate cancer and investigated the potential role of smoothened (SMO) in the pathogenesis of NEPC.MethodsSix public datasets, each containing cases of prostate adenocarcinoma (AdPC) and NEPC, were analyzed to compare the differential messenger RNA (mRNA) expression of six classic Hh signaling genes. The SMO, synaptophysin, chromogranin A (CHGA) and androgen receptor (AR) proteins were evaluated in human tissues from 5 cases of NEPC, 2 cases of AdPC mixed with NEPC, 2 cases of AdPC with neuroendocrine differentiation and 22 cases of high‐grade AdPC as determined by an immunohistochemistry assay. Gene set enrichment analysis (GSEA) was performed to identify relevant genetic signatures associated with SMO expression based on the public datasets. Stable SMO‐knockdown LNCaP and C4‐2B cells were established with a lentiviral system, and the expression of SMO, Gli1, AR, prostate‐specific antigen (PSA), and REST was assessed by real‐time polymerase chain reaction and western blot. Secreted PSA in the conditioned medium was assessed by ELISA. Gli1 was ectopically expressed performed by the transfection of Gli1 complementary DNA into SMO‐knockdown LNCaP cells, and western blot was used to assess of AR and PSA expression.ResultsThe mRNA level of SMO was dramatically downregulated in NEPC samples compared with AdPC samples in all 6 public datasets. SMO protein loss was observed in 100% of NEPC samples but in only 9% (2 of 22) of high‐grade AdPC samples. GSEA results showed that SMO loss was closely correlated with AR signaling activity. Stable SMO knockdown significantly attenuated AR signaling activity and suppressed AR expression, while Gli1 overexpression partially reversed the inhibitory effects of SMO knockdown on AR signaling activity and AR expression in LNCaP and C4‐2B cells.ConclusionThese results demonstrate that SMO loss is a characteristic of NEPC and that detecting SMO by IHC could aid pathologists in NEPC diagnosis. SMO loss may promote NEPC pathogenesis by modulating AR signaling.

The Difficulty of Post-Operative Surveillance of Calcitonin Negative Medullary Thyroid Cancer

Background: As a differentiated thyroid tumor, medullary thyroid cancer (MTC) typically maintains the secretory function of the c-cells with resultant increase in serum calcitonin level along with frequent elevations in serum chromogranin A (CgA) and carcinoembryonic antigen (CEA). Clinical Presentation: A 71-year-old female with history of multinodular goiter underwent a thyroid nodule biopsy after routine ultrasound surveillance revealed enlargement of two right lower lobe nodules compared with prior imaging. Fine needle aspiration (FNA) of one 3.1 x 1.9 x 2.7 cm right thyroid nodule revealed cellular material composed of spindle-shaped neoplastic cells, some of them with marked cytologic atypia, suspicious for a neuroendocrine tumor, specifically medullary thyroid carcinoma. A PET/CT scan was performed after injection of Gallium-68 dotatate radiotracer and revealed intense focal radiotracer activity in the approximately 2.5 x 2.1 cm right thyroid mid lower pole heterogeneous hypodense mass with tiny calcification inferiorly, consistent with the patient’s known tumor. There was no evidence of cervical octreotate avid metastatic lymphadenopathy and a chest x-ray showed no evidence of active pulmonary disease. The patient subsequently underwent a right partial thyroidectomy with isthmusectomy. Histopathology revealed a 2.8 x 1.9 x 1.9 cm neoplasm composed of spindle and polygonal cells growing in solid nests with neuroendocrine-type nuclei. Immunostains showed the tumor to be positive for AE1-AE3 cytokeratins, chromogranin, synaptophysin and CEA. It was focally positive for TTF-1 and calcitonin. Thyroglobulin and PAX-8 were negative. Using the AJCC 8th edition staging system, the tumor was staged a pT2Nx with margins uninvolved by carcinoma and no extrathyroidal extension or lymphatic invasion. Angioinvasion was present. Additional serum studies included a normal calcitonin value of <2.0 pg/ml (reference range 0-5.1 pg/ml), CEA 2.6 ng/ml (reference range <6.0 ng/ml), and a mildly elevated chromagranin A at 133 ng/ml (reference range 0-95 ng/ml). Plasma metanephrines, normetanephrines, vasoactive peptide, and glucagon levels were all unremarkable. Our patient’s surgical recovery was normal and two months later she remained asymptomatic without evidence of recurrence or metastasis. Discussion: The diagnosis and post-operative surveillance of medullary thyroid cancer is challenging; even more complicated is the rare case of calcitonin-negative MTC. The cause of calcitonin-negative MTC remains unclear. Further studies are needed for the discovery and development of novel biomarkers for post-operative surveillance and evaluation of clinical relapse.

Cerebral Venous Sinus Thrombosis as a First Presentation of Glucagonoma

Background: Glucagonoma is a very rare type of pancreatic neuroendocrine tumor (pNET) which represent about 2% of all pNETs (Yao et al.). Although glucagonoma can occur in multiple endocrine tumor syndromes (e.g., MEN-1), most cases are non-hereditary (John & Schwartz). The typical 4Ds presentation are diabetes (DM), depression, dermatosis, & deep vein thrombosis (DVT) (Cunha-Silva et al.). About 50% of glucagonoma patients have DVT during their disease course (Feingold et al.). Most reported DVT cases in glucagonoma are either lower limb DVT or pulmonary embolism (Teixeira, Nico & Ghideti; Castro et al.). To our knowledge, there is no report of a cerebral venous sinus thrombosis (CVST) as the first presentation for glucagonoma. Clinical Case: A 67-year-old male with a history of psoriasis & benign prostatic hyperplasia presented to the emergency department with a diffuse headache. He was sent home with conservative management. Four days later, he developed acute left-sided weakness with numbness & facial droop. CT head with contrast revealed a superior sagittal sinus thrombosis extending into the right transverse & right sigmoid sinuses. Heparin infusion was initiated. Due to the extensive sinus vein thrombosis & lack predisposing conditions, a pan CT was done for possible malignancy. The scan showed a solid, well-defined, markedly enhancing lesion in the pancreatic tail, suggestive of a NET. At the same time, a new diagnosis of type 2 DM was made based on HbA1C of 11.8%. The patient denied any diarrhea, fever, abdominal pain or episodes suggestive of hypoglycemia. However, he endorsed night sweats with weight loss. His family history was significant for a brother who had a pNET that was resected. Endocrinology was consulted, & a workup for pNET was ordered. Chromogranin A (CgA) was elevated at 439.9 ng/ml (<=82), while on PPI. 24-hour urine cortisol was normal. PTH, serum calcium, & the pituitary hormonal panel were all normal. hCG & CEA were normal. Given the new onset DM & DVT plasma glucagon was requested & came back elevated at 202 pg/ml (reference range 80 pg/ml). MRI showed an hypervascular T2 isointense lesion at the pancreas’ tail measuring 10 x 11 x 10 mm. A Ga68-DOTATATE PET scan was ordered. With this constellation of findings, we initiated somatostatin analog therapy while surgical resection was planned. We referred the patient to medical genetics. Conclusion: DVT is a common presentation in glucagonoma & a major cause of mortality. The possible mechanism appears to be related to increased secretion of factor X by pancreatic alpha cells (Lobo et al.). Although DVT is not unusual, an extensive CVST as the first presentation in glucagonoma has not been reported. In this case, & in addition to unexplained DVT, the new diagnosis of DM in an elderly patient raised the suspicion of secondary causes. Such a presentation should encourage clinicians to broaden the differential diagnoses, including pNET.

Myocardial perfusion SPECT as a potential mediator on circulating chromogranin A in patients with old myocardial infarction.

Chromogranin A (CgA) is a soluble polypeptide stored within and released from secretory granules of endocrine and other cell types (including cardiomyocytes); CgA appears to be a marker of the overall neuroendocrine activity. Increased levels of serum CgA have been found not only in patients with neuroendocrine neoplasms but also with other malignancies, hypertension, myocardial infarction, heart, or renal failure. A population of 307 patients (202 males, 105 females) was enrolled. The study group consisted of 118 individuals (38.4%) with myocardial infarction more than one year old (MI group); the remaining 189 (61.6%) had no known heart disease (control group). All patients underwent myocardial perfusion scintigraphy (MPS) after blood withdrawal for serum CgA measurement. To test whether a possible effect of old infarction on serum CgA is mediated by MPS findings, we employed analysis of covariance for three distinct categories of left ventricular (LV) perfusion deficits as dichotomous predictors: (1) any-type deficits (abnormal MPS); (2) reversible deficits (ischemia); and (3) fixed deficits (scar). In all three MPS conditions, the effect of age, gender, and LV ejection fraction (EFLV) on serum CgA was statistically significant: women exhibited higher CgA levels than men (P=0.008-0.023), whereas increasing age and decreasing EFLV were associated with increasing CgA (all P<0.001). Conversely, no statistically significant differences in mean CgA levels were found between MI patients and normal controls with either abnormal MPS, scar, or ischemia, or their degree and extent. Although serum CgA is significantly associated with age, gender, and EFLV in patients with an old MI, no association was found between CgA levels and either old MI history or MPS findings. The verified involvement of circulating CgA in the acute/subacute phase of infarction appears to be blunted in infarctions older than a year.

Evaluation of SSTR2 Expression in SI-NETs and Relation to Overall Survival after PRRT

Simple SummarySmall intestinal neuroendocrine tumors (SI-NETs) are slow growing tumors expressing somatostatin receptors (SSTR), which are targeted in diagnostic and therapeutic methods. A fairly new treatment that targets SSTR2 is peptide receptor radionuclide therapy (PRRT), which prolongs survival for patients with metastasized NETs. However, the treatment is costly, and the effect is variable. Therefore, finding predictors for treatment response is warranted. The aim of this retrospective study was to immunohistochemically analyze the SSTR2 expression in SI-NETs, using a previously constructed tissue microarray, and to investigate if a high SSTR2 expression was correlated to overall survival (OS). Among 42 patients that had received PRRT, 10 had at least one tumor with low SSTR2 expression. The patients were grouped according to the SSTR2 expression (“High SSTR2” and “Low SSTR2”) in previously resected tumors. In contrast to the hypothesis of the study, patients with low SSTR2 expression had significantly longer OS after PRRT, compared with patients with high SSTR2 expression. Hence, the study suggests that low SSTR2 expression in resected tumors should not exclude SI-NET patients from receiving PRRT.(1) Purpose: Small intestinal neuroendocrine tumors (SI-NETs) often present with distant metastases at diagnosis. Peptide receptor radionuclide therapy (PRRT) with radiolabeled somatostatin analogues is a systemic treatment that increases overall survival (OS) in SI-NET patients with stage IV disease. However, the treatment response after PRRT, which targets somatostatin receptor 2 (SSTR2), is variable and predictive factors have not been established. This exploratory study aims to evaluate if SSTR2 expression in SI-NETs could be used to predict OS after PRRT treatment. (2) Methods: Using a previously constructed Tissue Micro Array (TMA) we identified tissue samples from 42 patients that had received PRRT treatment during 2006–2017 at Sahlgrenska University hospital. Immunohistochemical expression of SSTR2, Ki-67 and neuroendocrine markers synaptophysin and Chromogranin A (CgA) were assessed. A retrospective estimation of 177Lu-DOTATATE uptake in 33 patients was performed. Data regarding OS and non-surgical treatment after PRRT were collected. Another subgroup of 34 patients with paired samples from 3 tumor sites (primary tumor, lymph node and liver metastases) was identified in the TMA. The SSTR2 expression was assessed in corresponding tissue samples (n = 102). (3) Results: The patients were grouped into Low SSTR2 or High SSTR2 groups based upon on levels of SSTR2 expression. There was no significant difference in 177Lu-DOTATATE uptake between the groups. The patients in the Low SSTR2 group had significantly longer OS after PRRT than the patients in the High SSTR2 group (p = 0.049). PRRT treated patients with low SSTR2 expression received less additional treatment compared with patients with high SSTR2 expression. SSTR2 expression did not vary between tumor sites but correlated within patients. (4) Conclusion: The results from the present study suggest that retrospective evaluation of SSTR2 expression in resected tumors cannot be used to predict OS after PRRT.

Application of INSM1 in Diagnosis and Grading of Laryngeal Neuroendocrine Carcinoma.

Chromogranin (CHG), synaptophysin (Syn), and CD56 are generally used in a panel to support diagnoses of laryngeal neuroendocrine carcinomas (NECs). However, the absence of expression of these markers does not completely exclude the diagnosis. INSM1 is a novel marker that is considered sufficiently sensitive and specific for NE differentiation. The aim of this study is not only to detect its sensitivity and specificity, but also to evaluate its application in grading for laryngeal NECs. The clinicopathological characteristics of the 25 cases with laryngeal NECs were retrospectively analyzed. The expressions of INSM1, CHG, Syn, and CD56 were detected by immunohistochemistry. Of the 25 laryngeal NECs, INSM1 had higher sensitivity (92%) than Syn (84%), CHG (76%) and CD56 (76%). The average H scores of INSM1, CD56, Syn, and CHG were 160, 37.5, 300, 300 for well-differentiated neuroendocrine carcinoma (WD-NEC); 190, 149, 209, 215 for moderately differentiated neuroendocrine carcinoma (MD-NEC); 251, 208, 104, 25 for poorly differentiated neuroendocrine carcinoma with small cell (SCNEC); 109, 160, 98, 26 for large cell types (LCNEC), respectively. Of these 98 non-neuroendocrine tumors, INSM1 expression was seen in nine (9%) tumors, all were squamous cell carcinoma. And INSM1 staining was generally focal. INSM1 has high sensitivity and specificity in diagnosis of laryngeal NECs. For grading laryngeal NECs, Syn and CHG showed significant advantages in the diagnosis of WD-NEC and MD-NEC, whereas INSM1 and CD56 showed greater diagnostic value in the diagnosis of SCNEC and LCNEC, especially in SCNEC. 4 Laryngoscope, 131:E2662-E2668, 2021.

Diagnostic Immunostaining and Tumor Markers Predict the Prognosis of Esophageal Neuroendocrine Cell Carcinoma Patients.

Esophageal neuroendocrine carcinoma (ENEC) has a poor prognosis, and predicting the prognosis by examining various markers may contribute to the determination of treatment strategies. Therefore, a multiple-institution retrospective study was performed to identify biomarkers using diagnostic immunohistochemistry and serum tumor markers that predict the prognosis of patients with ENEC. The results of immunohistochemical examination and serum tumor markers were extracted from the data of 141 ENEC patients at 39 institutions certified by the Japan Esophageal Society. The study then examined correlations between these data and prognosis or treatment effects. The ENEC patients with positively for all expression of synaptophysin (Syn), chromogranin A (CgA), and CD56 had a significantly worse prognosis than the patients with other expression patterns. Additionally, surgery and chemoradiotherapy were significantly more effective treatments than chemotherapy for the patients who were not positive for all expressions of Syn, CgA, and CD56. In terms of serum tumor markers, the patients with a high neuron-specific enolase (NSE) value had a significantly worse prognosis than the patients with a normal NSE value, and complete response (CR) cases treated with chemotherapy were significantly fewer in the high-NSE group. The results of multivariate analysis demonstrated that high NSE levels were an independent poor prognostic factor for esophageal endocrine cell carcinoma. This study showed that positivity for all expressions of Syn, CgA, and CD56, and a high NSE value were significantly worse prognostic factors for ENEC patients than other expression patterns and may be important prognostic biomarkers of ENEC.

Immunosuppression of Macrophages Underlies the Cardioprotective Effects of CST (Catestatin).

[Figure: see text].