Association between preoperative Vasostatin-1 and pathological features of aggressiveness in localized nonfunctioning pancreatic neuroendocrine tumors (NF-PanNET)

Vasostatin-1 restores autistic disorders in an idiopathic autism model (BTBR T+ Itpr3tf/J mice) by decreasing hippocampal neuroinflammation

Chromogranin A (CgA), a ∼ 49 kDa acidic secretory protein, is ubiquitously distributed in endocrine and neuroendocrine cells and neurons. As a propeptide, CgA is proteolytically cleaved to generate several peptides of biological importance, including pancreastatin (PST: hCgA250-301), Vasostatin 1 (VS1: hCgA1-76), and catestatin (CST: CgA 352-372). VS1 represents the most conserved fragment of CgA. A 20 amino acid domain within VS1 (CgA 47-66) exhibits potent antimicrobial and anti-inflammatory activities. Autism is known to be associated with inflammation. Therefore, we seek to test the hypothesis that VS1 modulates autism behaviors by reducing inflammation in the hippocampus. Treatment of C57BL/6 (B6) and BTBR (a mouse model of idiopathic autism) mice with VS1 revealed the following: BTBR mice showed a significant decrease in chamber time in the presence of a stranger or a novel object. Treatment with VS1 significantly increased chamber time in both cases, underscoring a crucial role for VS1 in improving behavioral deficits in BTBR mice. In contrast to chamber time, sniffing time in BTBR mice in the presence of a stranger was less compared to B6 control mice. VS1 did not improve this latter parameter. Surprisingly, sniffing time in BTBR mice in the presence of a novel object was comparable with B6 mice. Proinflammatory cytokines such as IL-6 and IL-1b, as well as other inflammatory markers, were elevated in BTBR mice, which were dramatically reduced after supplementation with VS1. Interestingly, even Beclin-1/p62, pAKT/AKT, and p-p70-S6K/p70-S6K ratios were notably reduced by VS1. We conclude that VS1 plays a crucial role in restoring autistic spectrum disorders (ASD) plausibly by attenuating neuroinflammation.

Critical appraisal of the adequacy of surgical indications for non-functioning pancreatic neuroendocrine tumours

BACKGROUND

The lack of preoperative prognostic factors to accurately predict tumour aggressiveness in non-functioning pancreatic neuroendocrine tumours may result in inappropriate management decisions. This study aimed to critically evaluate the adequacy of surgical treatment in patients with resectable non-functioning pancreatic neuroendocrine tumours and investigate preoperative features of surgical appropriateness.

METHODS

A retrospective study was conducted on patients who underwent curative surgery for non-functioning pancreatic neuroendocrine tumours at San Raffaele Hospital (2002-2022). The appropriateness of surgical treatment was categorized as appropriate, potential overtreatment and potential undertreatment based on histologic features of aggressiveness and disease relapse within 1 year from surgery (early relapse).

RESULTS

A total of 384 patients were included. Among them, 230 (60%) received appropriate surgical treatment, whereas the remaining 154 (40%) underwent potentially inadequate treatment: 129 (34%) experienced potential overtreatment and 25 (6%) received potential undertreatment. The appropriateness of surgical treatment was significantly associated with radiological tumour size (P < 0.001), tumour site (P = 0.012), surgical technique (P < 0.001) and year of surgical resection (P < 0.001). Surgery performed before 2015 (OR 2.580, 95% c.i. 1.570 to 4.242; P < 0.001), radiological tumour diameter < 25.5 mm (OR 6.566, 95% c.i. 4.010 to 10.751; P < 0.001) and pancreatic body/tail localization (OR 1.908, 95% c.i. 1.119 to 3.253; P = 0.018) were identified as independent predictors of potential overtreatment. Radiological tumour size was the only independent determinant of potential undertreatment (OR 0.291, 95% c.i. 0.107 to 0.791; P = 0.016). Patients subjected to potential undertreatment exhibited significantly poorer disease-free survival (P < 0.001), overall survival (P < 0.001) and disease-specific survival (P < 0.001).

CONCLUSIONS

Potential overtreatment occurs in nearly one-third of patients undergoing surgery for non-functioning pancreatic neuroendocrine tumours. Tumour diameter emerges as the sole variable capable of predicting the risk of both potential surgical overtreatment and undertreatment.

Recent developments in the diagnosis of pancreatic neuroendocrine neoplasms

INTRODUCTION

Pancreatic Neuroendocrine Neoplasms (PanNENs) are characterized by a highly heterogeneous clinical and biological behavior, making their diagnosis challenging. PanNENs diagnostic work-up mainly relies on biochemical markers, pathological examination, and imaging evaluation. The latter includes radiological imaging (i.e. computed tomography [CT] and magnetic resonance imaging [MRI]), functional imaging (i.e. 68Gallium [68 Ga]Ga-DOTA-peptide PET/CT and Fluorine-18 fluorodeoxyglucose [18F]FDG PET/CT), and endoscopic ultrasound (EUS) with its associated procedures.

AREAS COVERED

This review provides a comprehensive assessment of the recent advancements in the PanNENs diagnostic field. PubMed and Embase databases were used for the research, performed from inception to October 2023.

EXPERT OPINION

A deeper understanding of PanNENs biology, recent technological improvements in imaging modalities, as well as progresses achieved in molecular and cytological assays, are fundamental players for the achievement of early diagnosis and enhanced preoperative characterization of PanNENs. A multimodal diagnostic approach is required for a thorough disease assessment.

Role of chromogranin A-derived fragments after resection of nonfunctioning pancreatic neuroendocrine tumors

PURPOSE

No single reliable biomarker is available for nonfunctioning pancreatic neuroendocrine tumors (NF-PanNETs). Vasostatin-1 (VS-1), the N-terminal fragment of chromogranin A (CgA), seems to be a more accurate biomarker compared to its precursor. Primary aim was to investigate the ability of VS-1, compared to total-CgA, to assess the effectiveness of surgical resection performed for NF-PanNETs. Secondary aim was to evaluate two additional CgA-derived fragments, pancreastatin (PST) and vasostatin-2 (VS-2), as possible biomarkers for NF-PanNETs.

METHODS

Consecutive patients who underwent surgery for NF-PanNETs at San Raffaele Scientific Institute were included (n = 35). Plasma levels of CgA and CgA-derived fragments were measured by Enzyme-Linked ImmunoSorbent Assay (ELISA), preoperatively and postoperatively.

RESULTS

Preoperative VS-1 was significantly higher compared to VS-1 measured on postoperative day 5 (POD5) (pre: 0.338 nM versus POD5: 0.147 nM, P < 0.001), whereas total-CgA significantly increased after surgery (pre: 1.123 nM versus POD5: 1.949 nM, P = 0.006). Overall, 24 patients showed ≥ 1 feature of tumor aggressiveness (T3-T4, nodal/distant metastases, Ki67 > 5%, microvascular/perineural invasion, necrosis). The median percentage decrease in VS-1 plasma levels was 63% (IQR 28-88%) among patients with aggressive tumors, compared to 13% (IQR 0-57%) in the remaining population (P = 0.033). No significant differences in terms of PST (P = 0.870) and VS-2 (P = 0.909) were observed between preoperative and postoperative time.

CONCLUSION

VS-1 provides an early assessment of surgical efficacy in patients who undergo resection for NF-PanNETs, especially in those with aggressive neoplasms. Total-CgA, PST and VS-2 have no clinical utility in this setting.

Protective effect of vasostatin-1 plasmid-like nanoparticles on aortic aneurysm and its mechanism

Vasostatin 1 (VS-1) plays an important role in the regulation of various tissue injury and repair processes, but its role in aortic aneurysm remains unclear. The plasmid-like nanoparticles containing the vasostatin-1 gene Pul-PGEA-pCas-sgVs-1 were constructed, and their guarantee, safety, hemolysis, and particle size were analyzed. Eighty-four eight-week-old male ApoE-mice were randomly divided into blank group (without any treatment), model group (Ang II aortic aneurysm model + tail injection of PBS), control group (modeling + tail injection of Pul-PGEA-pCas9), and experimental group (modeling + tail injection of Pul-PGEA-pCas-sgVs-1), with 21 rats in each group. The incidence, mortality, and maximum diameter of abdominal aortic aneurysm (AAA) and the contents of high sensitivity C-reactive protein (HS-CRP), soluble intercellular adhesion molecule-1 (ICAM-1), soluble vascular cell adhesion molecule-1 (VCAM-1), and TNF-a in serum were compared in different groups of mice. The results showed that Pul-PGEA-pCas-sgVs-1 had good biosafety and transfection ability. The maximum diameter of abdominal aorta, incidence of abdominal aortic aneurysm, mortality, and the expression levels of HS-CRP, ICAM-1, VCAM-1, and TNF-a in the experimental group were lower than those in the model group (P< 0.05). These results indicated that the plasmid-like nanoparticles Pul-PGEA-pCas-sgVs-1 can inhibit the development of aorta by down-regulating the expression of inflammatory factors, which played a good protective role on the aorta.

Prognostic Significance of Microvascular Invasion in Pancreatic Ductal Adenocarcinoma: A Systematic Review and Meta-Analysis

BACKGROUND The incidence, pathogenesis, and prognostic effect of microvascular invasion on pancreatic ductal adenocarcinoma (PDAC) remain controversial. This study aimed to summarize the incidence, pathogenesis, role in clinical management, recurrence, and prognostic significance of microvascular invasion in PDAC. MATERIAL AND METHODS A literature review and meta-analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Systematic literature searches were conducted using PubMed and Google Scholar up to February 2021. RESULTS Seventeen studies were included in the meta-analysis. The incidence of microvascular invasion was 49.0% (95% confidence interval [CI], 43.8-54.5%) among PDAC patients who underwent surgery. The weighted multivariate Cox proportional hazards model hazard ratio for disease-free survival of 8 studies was 1.78 (95% CI 1.53-2.08, P<0.001), and there was no statistically significant difference between the subgroups (P=0.477). The hazard ratio for overall survival of 14 studies was 1.49 (95% CI 1.27-1.74, P<0.001), and there was no statistically significant difference between the subgroups (P=0.676). CONCLUSIONS Microvascular invasion occurred in nearly half of PDAC patients after surgery and was closely related to disease-free and overall survival. Understanding the role of microvascular invasion in PDAC will help provide more personalized and effective preoperative or postoperative strategies to achieve better survival outcomes.

Update on gastroenteropancreatic neuroendocrine tumors

The incidence gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) has dramatically risen over the last three decades, probably due to the increased detection of asymptomatic lesions. The diagnostic work-up for patients with suspected GEP-NENs is based on conventional imaging, endoscopy, pathology, and functional imaging, including ⁶⁸Gallium-DOTATATE PET and ¹⁸F-FDG PET. The choice of the best treatment strategy should be based on the evaluation of tumor-related features and patient's characteristics. A conservative management, consisting of active surveillance or endoscopic resection, has been advocated for patients with small, incidentally discovered, nonfunctioning tumors without features of aggressiveness. On the other hand, surgery with lymphadenectomy, also with a minimally invasive approach, represents the gold standard for the curative treatment of localized disease. Moreover, surgical resection plays an important role also in the context of a multimodal treatment strategy for patients with advanced GEP-NENs. Finally, a wide range of medical therapies, comprising somatostatin analogues, peptide receptor radionuclide therapy, target therapies and several chemotherapy regimens, can be offered to patients with advanced GEP-NENs not amenable of surgical resection, according to the biological and molecular features of their disease.

A Preoperative Clinical Risk Score Including C-Reactive Protein Predicts Histological Tumor Characteristics and Patient Survival after Surgery for Sporadic Non-Functional Pancreatic Neuroendocrine Neoplasms: An International Multicenter Cohort Study

Background: Oncological survival after resection of pancreatic neuroendocrine neoplasms (panNEN) is highly variable depending on various factors. Risk stratification with preoperatively available parameters could guide decision-making in multidisciplinary treatment concepts. C-reactive Protein (CRP) is linked to inferior survival in several malignancies. This study assesses CRP within a novel risk score predicting histology and outcome after surgery for sporadic non-functional panNENs. Methods: A retrospective multicenter study with national exploration and international validation. CRP and other factors associated with overall survival (OS) were evaluated by multivariable cox-regression to create a clinical risk score (CRS). Predictive values regarding OS, disease-specific survival (DSS), and recurrence-free survival (RFS) were assessed by time-dependent receiver-operating characteristics. Results: Overall, 364 patients were included. Median CRP was significantly higher in patients >60 years, G3, and large tumors. In multivariable analysis, CRP was the strongest preoperative factor for OS in both cohorts. In the combined cohort, CRP (cut-off ≥0.2 mg/dL; hazard-ratio (HR):3.87), metastases (HR:2.80), and primary tumor size ≥3.0 cm (HR:1.83) showed a significant association with OS. A CRS incorporating these variables was associated with postoperative histological grading, T category, nodal positivity, and 90-day morbidity/mortality. Time-dependent area-under-the-curve at 60 months for OS, DSS, and RFS was 69%, 77%, and 67%, respectively (all p < 0.001), and the inclusion of grading further improved the predictive potential (75%, 84%, and 78%, respectively). Conclusions: CRP is a significant marker of unfavorable oncological characteristics in panNENs. The proposed internationally validated CRS predicts histological features and patient survival.