Genetic polymorphisms of inflammatory response gene TNF-α and its influence on sporadic pancreatic neuroendocrine tumors predisposition risk

Pancreatic Neuroendocrine Tumors-Diagnostic Pitfalls of Non-Diabetic Severe Hypoglycemia: Literature Review and Case Report

Background: Hypoglycemia in the case of persons without diabetes is a rare event, being usually, initially misinterpreted based on the symptoms that can mimic various diseases, especially of a neuro-psychiatric nature. In the case of the identification of insulin-mediated hypoglycemia, the evaluation of pancreatic neuroendocrine tumors, which represent the most common and worrisome causes of non-diabetic insulin-mediated hypoglycemia, must be considered. Case Report: We present the case of a 57-year-old patient, hospitalized for a history of approximately one month of recurrent episodes of symptoms suggestive for severe hypoglycemia. The biological evaluation performed during an episode of hypoglycemia showed a plasma glucose value of 44 mg/dL, insulinemia 16.3 µU/mL, C peptide 3.72 ng/mL, HbA1c 4.99%, absence of urinary ketone bodies and anti-insulin antibodies <0.03 U/mL. The CT and MRI examination showed a 15.3/15 mm rounded tumor in the pancreatic corporeo-caudal region. The pancreatic tumor formation was enucleated and the histopathological and immunohistochemical analysis confirmed the diagnosis of the pancreatic neuroendocrine tumor with a positive reaction for chromogranin A, synaptophysin and insulin, without malignancy features (Ki 67 positive in 1% of the tumor cells). The postoperative evolution was favorable, without episodes of hypoglycemia, the fasting insulinemia one day after surgery being 4.1 µU/mL and HbA1c at three weeks postoperatively being 5.51%. Conclusions: The management of patients with hyperinsulinemic hypoglycemia secondary to insulinoma involves multidisciplinary collaboration with an important role in recognizing symptoms suggestive of hypoglycemia in a person without diabetes, initiating biological and imaging evaluation, establishing the optimal therapeutic option and histopathological confirmation.

Circulating cytokines allow for identification of malignant intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are the precursor lesions of pancreatic cancers, requiring active surgical intervention during cancer development. However, the current criteria for predicting malignant IPMNs remain challenging and limited. Hence, this study aimed to assess the discriminatory performance of circulating cytokines, including TNF-α, IL-2R, IL-6, and IL-8, then build a novel predictive model to improve the diagnostic accuracy.

METHOD

A total of 131 retrospective (from March 2016 to December 2019) and 53 prospective (from March 2020 to January 2021) patients who were histologically confirmed as IPMNs were consecutively collected and analyzed.

RESULT

The circulating levels of TNF-α, IL-2R, IL-6, and IL-8 were significantly elevated in malignant IPMNs, and were verified as independent factors for malignant IPMNs (p < 0.05). Then, a novel score, the circulating cytokine score (CCS), was calculated and demonstrated as an independent predictive indicator with a higher area under the curve (AUC) than each cytokine alone (p < 0.001). Besides the CCS, two high-risk stigmata features, the presence of solid component (PSC), and main pancreatic duct (MPD) dilation ≥10 mm were also demonstrated as independent indicators for predicting malignant IPMNs. Finally, a novel nomogram incorporating the CCS and these two high-risk stigmata features presented a remarkable diagnostic performance, both in the training and validation cohorts with AUCs of 0.928 and 0.873, respectively.

CONCLUSION

The CCS can be considered a novel independent predictive indicator for malignant IPMNs. Additionally, the formulated nomogram model integrating the CCS, PSC, and MPD ≥10 mm can be a valuable and promising tool for predicting the malignant transformation of IPMNs during long-term follow-ups to assist in timely and accurate surgical decisions.

Genetic Variants of the MIF Gene and Susceptibility of Rectal Cancer

BACKGROUND

Rectal cancer (RC) has been documented to be a highly invasive malignant neoplasm worldwide. Macrophage migration inhibitory factor (MIF) is a multifunctional cytokine involved in cell-mediated immunity, immunoregulation, inflammation. In vitro and in vivo studies have identified that MIF was involved in the carcinogenesis and progression of RC.

PATIENTS AND METHODS

This case-control study evaluated associations of genetic variants of the MIF gene and serum level of MIF with susceptibility of RC.

RESULTS

We found MIF level was associated with an increased risk of RC (OR for per unit: 1.38, 95% CI:1.32-1.44; P < 0.001). Both MIF rs2012133 (OR = 1.30; 95% CIs = 1.08-1.58; P = 0.007) and rs755622 (OR = 1.45; 95% CIs = 1.15-1.82; P = 0.002) were significantly associated with increased risk of RC. Besides, we also found MIF rs5844572 was significantly associated with increased susceptibility of RC, with OR for per CATT repeat of 1.28 (95% CIs: 1.16-1.41; P < 0.001). Further, we found all three variants of the MIF gene, rs5844572, rs2012133 and rs755622, could increase serum level of MIF.

CONCLUSION

This study suggests that MIF plays an important role in the carcinogenesis of RC and could be used as a biomarker for early detection and prediction of RC.

A systematic review and network meta-analysis of single nucleotide polymorphisms associated with pancreatic cancer risk

In this meta-analysis, we systematically investigated the correlation between single nucleotide polymorphisms (SNPs) and pancreatic cancer (PC) risk. We searched PubMed, Network Science, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), China Science and Technology Periodical Database (VIP), and Wanfang databases up to January 2020 for studies on PC risk-associated SNPs. We identified 45 case-control studies (36,360 PC patients and 54,752 non-cancer individuals) relating to investigations of 27 genes and 54 SNPs for this meta-analysis. Direct meta-analysis followed by network meta-analysis and Thakkinstian algorithm analysis showed that homozygous genetic models for CTLA-4 rs231775 (OR =0.326; 95% CI: 0.218-0.488) and VDR rs2228570 (OR = 1.976; 95% CI: 1.496-2.611) and additive gene model for TP53 rs9895829 (OR = 1.231; 95% CI: 1.143-1.326) were significantly associated with PC risk. TP53 rs9895829 was the most optimal SNP for diagnosing PC susceptibility with a false positive report probability < 0.2 at a stringent prior probability value of 0.00001. This systematic review and meta-analysis suggest that TP53 rs9895829, VDR rs2228570, and CTLA-4 rs231775 are significantly associated with PC risk. We also demonstrate that TP53 rs9895829 is a potential diagnostic biomarker for estimating PC risk.

Neuroendocrine Neoplasms of the Small Bowel and Pancreas

The traditionally promulgated perspectives of neuroendocrine neoplasms (NEN) as rare, indolent tumours are blunt and have been outdated for the last 2 decades. Clear increments in their incidence over the past decades render them increasingly clinically relevant, and at initial diagnosis many present with nodal and/or distant metastases (notably hepatic). The molecular pathogenesis of these tumours is increasingly yet incompletely understood. Those arising from the small bowel (SB) or pancreas typically occur sporadically; the latter may occur within the context of hereditary tumour predisposition syndromes. NENs can also be associated with endocrinopathy of hormonal hypersecretion. Tangible advances in the development of novel biomarkers, functional imaging modalities and therapy are especially applicable to this sub-set of tumours. The management of SB and pancreatic neuroendocrine tumours (NET) may be challenging, and often comprises a multidisciplinary approach wherein surgical, medical, interventional radiological and radiotherapeutic modalities are implemented. This review provides a comprehensive overview of the epidemiology, pathophysiology, diagnosis and treatment of SB and pancreatic NETs. Moreover, we provide an outlook of the future in these tumour types which will include the development of precision oncology frameworks for individualised therapy, multi-analyte predictive biomarkers, artificial intelligence-derived clinical decision support tools and elucidation of the role of the microbiome in NEN development and clinical behaviour.

RSUME is implicated in tumorigenesis and metastasis of pancreatic neuroendocrine tumors

The factors triggering pancreatic neuroendocrine tumor (PanNET) progression are largely unknown. Here we investigated the role and mechanisms of the sumoylation enhancing protein RSUME in PanNET tumorigenesis. Immunohistochemical studies showed that RSUME is strongly expressed in normal human pancreas, in particular in β-cells. RSUME expression is reduced in insulinomas and is nearly absent in other types of PanNETs suggesting a role in PanNET tumorigenesis. In human pancreatic neuroendocrine BON1 cells, RSUME stimulates hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor-A (VEGF-A), which are key components of tumor neovascularisation. In contrast, RSUME suppresses nuclear factor-κB (NF-κB) and its target interleukin-8 (IL-8). Correspondingly, PanNET cells with RSUME knockdown showed decreased HIF-1α activity and increased NF-κB and IL-8 production leading to a moderate reduction of VEGF-A release as reduced HIF-1α/VEGF-A production is partly compensated by NF-κB/IL-8-induced VEGF-A. Notably, RSUME stabilizes the tumor suppressor PTEN, which is frequently lost in PanNETs and whose absence is associated with metastasis formation. In vivo orthotopic transplantation of PanNET cells with or without RSUME expression into nude mice showed that PanNETs without RSUME have reduced PTEN expression, grow faster and form multiple liver metastases. In sum, RSUME differentially regulates key components of PanNET formation suggesting that the observed loss of RSUME in advanced PanNETs is critically involved in PanNET tumorigenesis, particularly in metastasis formation.

The role of inflammatory cytokines and tumor associated macrophages (TAMs) in microenvironment of pancreatic cancer

Pancreatic cancer is considered as one of the most lethal types of cancer due to its poor prognosis and lack of effective therapeutic approaches. Although many studies have been done on pancreatic cancer, the current treatment methods did not exhibit successful results. Hence, novel strategies are needed for treatment of pancreatic cancer. The microenvironment of pancreatic cancer contains many factors such as inflammatory cytokines and tumor associated macrophages (TAMs), which influence the tumor's status. These factors can be upregulated and consequently lead to exacerbation of tumor progression. Understanding the role of pro- and anti-inflammatory cytokines and the function of TAMs in the pancreatic cancer microenvironment might lead to development and improvement of novel strategies in the diagnosis and treatment of pancreatic cancer and may result in promising treatments for this type of cancer.

Risk Factors for Sporadic Pancreatic Neuroendocrine Tumors: A Case-Control Study

The current study examined risk factors for sporadic pancreatic neuroendocrine tumors (PNETs), including smoking, alcohol use, first-degree family history of any cancer (FHC), and diabetes in the Han Chinese ethnic group. In this clinic-based case-control analysis on 385 patients with sporadic PNETs and 614 age- and sex-matched controls, we interviewed subjects using a specific questionnaire on demographics and potential risk factors. An unconditional multivariable logistic regression analysis was used to estimate adjusted odds ratios (AORs). No significant differences were found between patients and controls in terms of demographic variables. Most of the patients with PNETs had well-differentiated PNETs (G1, 62.9%) and non-advanced European Neuroendocrine Tumor Society (ENETS) stage (stage I or II, 83.9%). Ever/heavy smoking, a history of diabetes and a first-degree FHC were independent risk factors for non-functional PNETs. Only heavy drinking was found to be an independent risk factor for functional PNETs (AOR = 1.87; 95% confidence interval [CI], 1.01–3.51). Ever/heavy smoking was also associated with advanced ENETS staging (stage III or IV) at the time of diagnosis. This study identified first-degree FHC, ever/heavy smoking, and diabetes as risk factors for non-functional PNETs, while heavy drinking as a risk factor for functional PNETs.

Genetic polymorphisms of interleukin 1β gene and sporadic pancreatic neuroendocrine tumors susceptibility

AIM

To evaluate the association between the interleukin 1β (IL-1β) polymorphisms and the pancreatic neuroendocrine tumor (pNET) development.

METHODS

A case-control study was conducted analyzing IL-1β polymorphisms using germline DNA collected in a population-based case-control study of pancreatic cancer (51 pNET cases, 85 pancreatic ductal adenocarcinoma cases, 19 intraductal papillary mucinous neoplasm and 98 healthy controls).

RESULTS

The distribution of genotypes for the -511 C/T polymorphism in the pNET patient groups showed significant difference compared to the control group. It is known that the carriers of the IL-1β -511T allele have increased concentrations of IL-1β. The -511 CT and TT high-expression genotypes were over-represented in pNET patients.

CONCLUSION

The findings of this study suggested a possible role of IL-1β -511 C/T genotypes in the pathogenesis of pNETs since the presence of the IL-1β -511 CT and TT genotypes and the T allele was associated with an increased risk of pNET only.

Risk factors for neuroendocrine neoplasms: a systematic review and meta-analysis

BACKGROUND

Neuroendocrine neoplasms (NENs) are rare cancers mainly of lung and digestive tract. Little is known on risk factors. The aim of this work is to define the risk factors for NEN development by extensive review and meta-analysis of published data.

METHODS

The search was conducted on Medline, Scopus, and Web of Science following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The Newcastle-Ottawa scale was used for study quality. Meta-analyses were conducted by primary site. Odds ratio (OR), hazard ratio, risk ratio, standardized incidence ratio, and associated 95% confidence intervals (CIs) were abstracted. Data were combined and analyses carried out for risk factors considered by at least two studies. Random-effects model was adopted for study variation.

RESULTS

Of 1535 extracted articles, 24 were enrolled. Meta-analyses were possible for pancreas, small intestine, and rectum. Risk for NEN associated with: (i) family history of cancer at all investigated sites (lung, stomach, pancreas, small intestine, appendix, and colon; OR 2.12 [95% CI 1.40-3.22, I(2) = 0.0%, P = 0.681] at meta-analysis in pancreas); (ii) body mass index (BMI) or diabetes (stomach, pancreas, and small intestine; OR of 2.76 [95% CI 1.65-4.64, I(2) = 58.5%, P = 0.090] for diabetes at meta-analysis in pancreas); (iii) cigarette smoking (lung, stomach, pancreas, and small intestine; OR of 1.34 [95% CI 1.10-1.63, I(2) = 0.0%, P = 0.780] and of 1.59 [95% CI 1.07-2.37, I(2) = 32.9%, P = 0.225] for smokers versus never-smokers at meta-analysis for pancreas and small intestine); (iv) alcohol consumption (pancreas and rectum; OR of 2.44 [95% CI 1.07-5.59, I(2) = 65.8%, P = 0.054] and of 1.53 [95% CI 0.99-2.35, I(2) = 0.0%, P = 0.630] for heavy drinkers versus never-drinkers at meta-analysis for pancreas and rectum).

CONCLUSIONS

Family history of cancer is the most relevant risk factor for NEN development at all investigated sites, followed by BMI and diabetes. Cigarette smoking and alcohol consumption are potential risk factors for selected anatomical sites.