Technical options in surgery for artery-involving pancreatic cancer: Invasion depth matters.

Background: The artery involvement explains the majority of primary unresectability of non-metastatic pancreatic cancer patients and both arterial resection and artery-sparing dissection techniques are utilized in curative-intent pancreatectomies for artery-involving pancreatic cancer (ai-PC) patients. Methods: This narrative review summarized the history of resectability evaluation for ai-PC and attempted to interpret its current pitfalls that led to the divergence of resectability prediction and surgical exploration, with a focus on the rationale and the surgical outcomes of the sub-adventitial divestment technique. Results: The circumferential involvement of artery by tumor currently defined the resectability of ai-PC but insufficient to preclude laparotomy with curative intent. The reasons behind could be: 1. The radiographic involvement of tumor to arterial circumference was not necessarily resulted in histopathological artery wall invasion; 2. the developed surgical techniques facilitated radical resection, better perioperative safety as well as oncological benefit. The feasibility of periadventitial dissection, sub-adventitial divestment and other artery-sparing techniques for ai-PC depended on the tumor invasion depth to the artery, i.e., whether the external elastic lamina (EEL) was invaded demonstrating a hallmark plane for sub-adventitial dissections. These techniques were reported to be complicated with preferable surgical outcomes comparing to arterial resection combined pancreatectomies, while the arterial resection combined pancreatectomies were considered performed in patients with more advanced disease. Conclusions: Adequate preoperative imaging modalities with which to evaluate the tumor invasion depth to the artery are to be developed. Survival benefits after these techniques remain to be proven, with more and higher-level clinical evidence needed. Key message: The current resectability evaluation criteria, which were based on radiographic circumferential involvement of the artery by tumor, was insufficient to preclude curative-intent pancreatectomies for artery-involving pancreatic cancer patients. With oncological benefit to be further proven, periarterial dissection and arterial resection have different but overlapping indications, and predicting the tumor invasion depth in major arteries was critical for surgical planning.

Cancer-testis gene STK31 is regulated by methylation and promotes the development of pancreatic cancer.

BACKGROUD: Pancreatic cancer (PC) is a highly invasive malignancy with extremely poor prognosis. STK31 has been identified as a cancer-testis (CT) gene, but its function in PC has not been elucidated well. METHODS: The effect of STK31 on cell proliferation, migration and invasion was investigated by in vitro and in vivo experiments and total RNA sequencing and targeted bisulfite sequencing was applied to explore the potential regulatory mechanisms of STK31 in PC. RESULTS: By analysis of tissue samples and the clinicopathologic features, we found that STK31 was reactivated in PC and associated with poor prognosis. In addition, the vitro and vivo studies indicated that STK31 could promote PC progression by facilitating cell proliferation, migration and invasion, and the indication. Targeted Bisulfite Sequencing showed that STK31 was regulated by methylation. Furthermore, the results of total RNA sequencing suggested that STK31 was closely related to signal transduction, metabolism, and the immune system. CONCLUSIONS: This study demonstrates that STK31, as a CT gene, can promote the development of PC and is regulated by methylation. STK31 could be considered as a potential therapeutic target for PC.

A histopathological study of artery wall involvement in pancreatic cancer surgery.

PURPOSE: This study aims to study the depth of artery wall tumour invasion in patients undergoing surgery for pancreatic ductal adenocarcinoma. METHODS: Specimens from 47 pancreatic cancer patients with major arterial (splenic, SA; celiac, CA; common hepatic, CHA) invasion were examined: 45 left (distal) pancreatectomies, including 11 celiac artery resections, and two total pancreatectomies. Dissection of tumour-invaded arteries in 25 fresh specimens was attempted ex vivo using the sub-adventitial dissection technique (SDT). Tumour invasion of 66 arteries was graded using the tumour-free distance (TFD) from the external elastic lamina (EEL): 0 = no arterial invasion; I = TFD ≥ 1 mm; II = TFD < 1 mm; and grade III = EEL invasion. RESULTS: AJCC TNM staging was IA = 1 (2%), IB = 4 (9%), IIA = 5 (11%), IIB = 17(36%) and III = 20 (43%). Grade III tumour invasion was found in 17/47(36%) SAs, in 5/11 (45%) CAs and in 1/8 (13%) CHAs (p = 0.318). Attempted ex vivo SDT undertaken in 33 arteries from 25 specimens was complete in 16 and incomplete in 17 arteries. The median (IQR) TFD was 0.97 (0.11-2.54) mm in dissected and 0.14 (0.10, 0.14) mm in non-dissected SAs (p = 0.034). EEL tumour invasion occurred in 0/12 (0%) dissected compared to 7/13 (54%) non-dissected SAs (p = 0.005). Grades 0, I, II and III invasion were found in four (33%), two (17%) and six (50%), respectively, of 12 dissected SAs and grades II and III in six 6 (46%) and seven (54%), respectively, of 13 non-dissected SAs (p = 0.002). CONCLUSIONS: The grading system described may form the basis for classification to further develop arterial dissection techniques for pancreatic cancer.

Single-layer continuous duct-to-mucosa pancreaticojejunostomy: "how we do it".

PURPOSE: Pancreatic anastomosis reconstruction is one of the most technically demanding and complicated procedures in general surgery. No single technique has been demonstrated to be superior to the others in the prevention of postoperative pancreatic fistula (POPF), and the accumulation of surgical experience is closely related to the quality of this anastomosis. The aim of the current study was to evaluate the feasibility of our simplified technique, single-layer continuous duct-to-mucosa pancreaticojejunostomy. METHODS: A single-center prospective single-arm trial was performed. The first 20 patients who underwent Whipple's procedure with the new technique performed by a single surgeon in our center were recruited. General information, preoperative treatments, risk factors for POPF, and postoperative morbidity of the patients were prospectively recorded and reported. RESULTS: From January to February 2020, 13 male and 7 female patients were included. Ten cases were classified as intermediate/high risk according to validated fistula prediction models. The median operation time was 260 min, including a median pancreaticojejunostomy time of 7.7 min. There were 2 cases (10%) of grade B POPF, and no grade C POPF occurred. The overall morbidity rate was 30%, including 2 cases with severe complications (Clavien-Dindo grade ≥ 3). No patients underwent reoperation, and no patient died within 90 days after surgery. The median length of hospitalization was 11 days. CONCLUSION: Single-layer continuous duct-to-mucosa pancreaticojejunostomy is a simplified and feasible method for pancreatic anastomosis. Further studies are warranted to evaluate the indications or contraindications and efficacy of preventing POPF with our new technique.

The short-term outcomes of distal pancreatectomy with portal vein/superior mesenteric vein resection.

BACKGROUND: Portal vein/superior mesenteric vein (PV/SMV) resection during distal pancreatectomy (DP) is often associated with technical difficulties due to the close anatomic relationship between pancreatic head and PV/SMV. In this paper, we present our operative technique and short-term outcomes of DP combined with venous resection (DP-VR) for left-sided pancreatic cancer (PC). METHODS: We reviewed 368 consecutive cases of DP for PC from January 2013 to December 2018 in our institution, and identified 41 patients (11.1%) who had undergone DP-VR. The remaining 327 DP patients (88.9%) were matched to DP-VR using propensity scores in the proportion of 1:2. Demographics, intraoperative details, postoperative complications and the pathological results were compared between the two groups. RESULTS: Out of the 41 DP-VR cases, in 14 (34.1%) venous resection with primary closure was performed, while the remaining 27 (65.9%) underwent end-to-end anastomosis without graft. A propensity-score-matched analysis revealed that DP-VR caused an increased risk of postoperative bleeding (17.1% vs. 3.7%, P = 0.016) and delayed gastric emptying (9.8% vs. 1.2%, P = 0.042) compared to standard DP. Overall morbidity (46.3% vs. 36.6%, P = 0.332), postoperative pancreatic fistula (31.7% vs. 26.8%, P = 0.672), R0 resection (58.5% vs. 67.1%, P = 0.223), 30-day reoperation (2.4% vs. 3.7%, P = 0.719), and 90-day mortality (0% vs. 2.5%, P = 0.550) were comparable between the two groups. In postoperative computed tomographic scans of 34 patients (82.9%) at a 90-day follow-up, PV/SMV stenosis was suggested in two patients (5.9%). CONCLUSION: Despite the higher rates of postoperative bleeding, DP-VR was found to be a feasible and safe surgery with acceptable postoperative morbidity and mortality compared to standard DP for left-sided pancreatic cancer.

Undifferentiated Carcinoma of Pancreas with Osteoclast-Like Giant Cells: One Center's Experience of 13 Cases and Characteristic Pre-Operative Images.

Background: Undifferentiated carcinoma of pancreas with osteoclast-like giant cells is an extremely rare tumor in pancreas. It is relatively difficult to have preoperative diagnosis due to the lack of specific tumor markers and pre-operative images. Methods: In the present study, database of the pancreas center in the First Affiliated Hospital of Nanjing Medical University was retrospectively screened. A total of thirteen cases diagnosed as undifferentiated carcinoma of pancreas with osteoclast-like giant cells were included. Their clinical data and treatments were collected. Results: Thirteen patients include eight males and five females, and the median age was 67 (60-72) years old. The lesions were found in more than half patients through health examination with no symptoms. NSE was elevated in eight cases (66%). CT scan revealed that cystic and solid lesions often had thick (4/5), contrast-enhanced (5/5) wall with smooth edges (5/5) and the boundary of lesions mainly with solid composition (4/10) is not well demarcated with normal pancreatic parenchyma. All patients received surgical resection. Eight patients had adjuvant chemotherapy and only one patient had adjuvant radiotherapy. The median survival time was 13 months. Five patients had postoperative metastasis or recurrence of tumor and four of them had died of this disease during follow-up. Conclusion: Our data showed that elevated level of NSE and characteristic pre-operative images might provide aid with the pre-operative diagnosis for undifferentiated carcinoma of pancreas with osteoclast-like giant cells. Patients with suspected diagnosis should receive surgical intervention as soon as possible, supplemented with postoperative chemotherapy, in order to prolong the survival of patients.

Selective use of pancreatic duct occlusion during pancreaticoduodenectomy in patients with a small-size duct and atrophic parenchyma in the distal pancreas: A retrospective study.

Background: Despite the advancements in surgical techniques, postoperative pancreatic fistula (POPF) remains a potentially life-threatening complication of pancreaticoduodenectomy (PD). Pancreatic duct occlusion (PDO) without anastomosis has also been proposed to alleviate the clinical consequences of POPF in selected patients after PD. Objectives: To assess the safety and effectiveness of PDO with mechanical closure after PD in patients with an atrophic pancreatic body-tail and a small pancreatic duct. Methods: We retrospectively identified two female and two male patients from April 2019 to October 2020 through preoperative computed tomography of the abdomen. Among them, three patients underwent PDO with mechanical closure after PD, and one underwent PDO after pylorus-preserving PD. In addition, patients' medical records and medium-and long-term follow-up data were analyzed. Results: Postoperative histological examination revealed a solid pseudopapillary tumor in two patients, pancreatic ductal adenocarcinoma in one patient, and chronic pancreatitis with pancreatic duct stones in one patient. However, none of the patients developed biochemical or clinically relevant POPF, with no postpancreatectomy hemorrhage, biliary leakage, delayed gastric emptying, intra-abdominal abscess, or chyle leakage. Among the four patients, three developed new-onset diabetes mellitus, and one had impaired glucose tolerance. Furthermore, three patients received pancreatic enzyme supplementation at a dose of 90,000 Ph. Eur. units/d, and one was prescribed a higher dose of 120,000 Ph. Eur. units/d. Conclusions: PDO with mechanical closure is an alternative approach for patients with an atrophic pancreatic body-tail and a small pancreatic duct after PD. Therefore, further evidence should evaluate the potential benefits of selective PDO in these patients.

Development of epithelial-mesenchymal transition-related lncRNA signature for predicting survival and immune microenvironment in pancreatic cancerwithexperiment validation.

Long non-coding RNAs (LncRNAs) have crucial function in epithelial-mesenchymal transition (EMT) in pancreatic cancer. It is necessary to comprehensively analyze the potential role of EMT-related lncRNA in pancreatic cancer. In the present study, genomic data of pancreatic cancer from the TCGA database were downloaded and we found 368 EMT-related lncRNAs. According to the expression characteristics of prognostic-related lncRNAs, all samples could be divided into two clusters with different clinical outcomes and different tumor microenvironments. Moreover, an eleven EMT-related lncRNAs signature was established and verified. Patients with pancreatic cancer in the high-risk group had a shorter overall survival than those in the low-risk group and the signature could act as an independent prognostic factor. Further analysis suggested that the EMT-related lncRNAs might affect the prognosis of patients through immune mechanisms. All findings indicated that the signature and eleven lncRNAs might serve as potential prognostic biomarkers and therapeutic targets in the treatment of pancreatic cancer.

Prognostic impact of the ratio of preoperative CA19-9 to liver enzyme levels in pancreatic cancer patients with jaundice (predictability of combined CA19-9/AST and CA19-9/γ-GGT for jaundiced PDAC patients).

BACKGROUND: Carbohydrate antigen 19-9 (CA19-9) has been reported as the most significant survival predictor of patients with pancreatic ductal adenocarcinoma (PDAC). However, the elevation of CA19-9 could interfere with obstructive jaundice and the predictive value of CA19-9 in PDAC patients with jaundice remains to be analyzed and elucidated to find possible adjustments. OBJECTIVE: To evaluate the predictability of preoperative CA19-9 and its adjustments for the overall survival (OS) of PDAC patients by analyzing the relationship between preoperative serum CA19-9 and total bilirubin (TBIL). METHODS: A total of 563 consecutive patients who underwent surgery for primary pancreatic adenocarcinoma in our center between January 2015 and September 2018 were retrospectively reviewed. Clinicopathologic information was collected and preoperative parameters such as CA19-9, CEA, TBIL, γ-GGT, AST, ALT, and ALP were recorded as well as overall survival rates, which began from the date of operation to that of death or the last follow-up. Kaplan-Meier survival curves with log-rank test and Cox regression models were applied using SPSS and the survival and survminer packages in R software. RESULTS: Using 39/390/1000 as the cut-off values for preoperative serum CA19-9, significant capability of OS stratification was found in the total cohort (p < 0.001, MST = 29.7/19.1/15.2/12.1 months) and patients with TBIL <102.6 µmol/L (p < 0.001, MST = 32.2/19.6/15.0/11.2 months). However, in the subgroup of TBIL≥102.6 µmol/L, this classification method was replaced by the combined scoring of CA19-9/AST and CA19-9/γ-GGT. CONCLUSIONS: As an independent predictor of overall survival of PDAC patients, preoperative serum CA19-9 is defective in survival stratification when TBIL≥102.6 µmol/L but a positive survival prognosis could be achieved with the application of combined preoperative CA19-9/AST and CA19-9/γ-GGT.

DUOX2 As a Potential Prognostic Marker which Promotes Cell Motility and Proliferation in Pancreatic Cancer.

DUOX2 has been reported to highly express in several types of cancers. However, the prognostic significance and the biological function of DUOX2 expression with pancreatic cancer (PC) still remain unclear. The present study is aimed at investigating whether DUOX2 could act as a novel biomarker of prognosis and evaluating its effect on PC cell progression. The mRNA and protein expression of DUOX2 in PC cells and tissues were assessed by quantitative real-time PCR (RT-qPCR) and immunohistochemistry. The effect of DUOX2 expression on PC cell motility and proliferation was evaluated in vitro. The correlation between DUOX2 mRNA expression and clinicopathological features and its prognostic significance were analyzed according to the Gene Expression Profiling Interactive Analysis (GEPIA) website based on The Cancer Genome Atlas (TCGA) and the GTEx databases combined with our clinical information. According to bioinformatics analysis, we forecasted the upstream transcription factors (TFs) and microRNA (miRNA) regulatory mechanism of DUOX2 in PC. The expression of DUOX2 at transcriptional and protein level was dramatically increased in PC specimens when compared to adjacent nontumor specimens. Functionally, DUOX2 knockdown inhibited cell motility and proliferation activities. Our clinical data revealed that the patients had better postoperative overall survival (OS) with lower expression of DUOX2, which is consistent with GEPIA data. Multivariate analysis revealed that high DUOX2 expression was considered as an independent prognostic indicator for OS (P = 0.031). Based on Cistrome database, the top 5 TFs of each positively and negatively association with DUOX2 were predicted. hsa-miR-5193 and hsa-miR-1343-3p targeting DUOX2 were forecasted from TargetScan, miRDB, and DIANA-TarBase databases, which were negatively correlated with OS (P = 0.043 and P = 0.0088, respectively) and DUOX2 expression (P = 0.0093 and P = 0.0032, respectively) in PC from TCGA data. These findings suggest that DUOX2 acts as a promising predictive biomarker and an oncogene in PC, which could be a therapeutic target for PC.

CircNEIL3 regulatory loop promotes pancreatic ductal adenocarcinoma progression via miRNA sponging and A-to-I RNA-editing.

BACKGROUND: A growing number of studies have focused on investigating circRNAs as crucial regulators in the progression of multiple cancer types. Nevertheless, the biological effects and underlying mechanisms of circRNAs in pancreatic ductal adenocarcinoma (PDAC) remain unclear. METHODS: Differentially expressed circRNAs between cancerous tissue and adjacent normal tissues were identified by RNA sequencing in PDAC. Subsequently, in vitro and in vivo functional experiments were performed to investigate the functional roles of circNEIL3 in PDAC tumour growth and metastasis. Furthermore, RNA pull-down, dual-luciferase reporter assays, RNA immunoprecipitation (RIP) assays, fluorescent in situ hybridization (FISH) and Sanger sequencing assays were performed to examine the circular interaction among circNEIL3, miR-432-5p and adenosine deaminases acting on RNA 1 (ADAR1). RESULTS: CircNEIL3 was upregulated in PDAC and promoted the progression of PDAC cells both in vitro and in vivo. Mechanistically, circNEIL3 was shown to regulate the expression of ADAR1 by sponging miR-432-5p to induce RNA editing of glioma-associated oncogene 1 (GLI1), ultimately influencing cell cycle progression and promoting epithelial-to-mesenchymal transition (EMT) in PDAC cells. Moreover, we discovered that the circNEIL3/miR-432-5p/ADAR1 axis was correlated with the PDAC clinical stage and overall survival of PDAC patients, while ADAR1 may reduce the biogenesis of circNEIL3. CONCLUSIONS: Our findings reveal that circNEIL3 facilitates the proliferation and metastasis of PDAC through the circNEIL3/miR-432-5p/ADAR1/GLI1/cell cycle and EMT axis and that its expression is regulated by ADAR1 through a negative feedback loop. Therefore, circNEIL3 may serve as a prognostic marker and a therapeutic target for PDAC.

Sub-adventitial divestment technique for resecting artery-involved pancreatic cancer: a retrospective cohort study.

PURPOSE: To introduce sub-adventitial divestment technique (SDT), a procedure to remove the tumor while preserving the artery during curative pancreatectomy. Peri-operative safety profile was also evaluated. METHODS: In a single center consecutive series of pancreatectomy for pancreatic cancer, the outcome of patients who had pancreatectomy with SDT was compared to standard pancreatic surgery. RESULTS: From June 2014 to June 2016, 72 patients had pancreatectomy with SDT and 235 had standard surgery. Tumor stage was T4 in all 72 (100%) tumors removed using SDT compared to four (2%) with standard pancreatectomy (p < 0.001). All 72 (100%) tumors in the SDT group were stage III compared to 24 (10%) in the standard surgery group (p < 0.001). Both groups had a high proportion of poorly differentiated tumors (52 (72%) and 163 (69%) respectively) and perineural tumor invasion (62 (86%) and 186 (79%) respectively). R1 (< 1 mm) was found in 24 (86%) of 28 tumors in the SDT group, and in 72 (60%) out of 120 standard pancreatectomy tumors (p = 0.01). Complications occurred in 29 (40%) of the SDT group and in 88 (37%) of the standard group. The in-hospital mortality was four (6%) in the SDT group and one (0.4%) in the standard group (p = 0.01), with a 90-day mortality of 5 (8%)/60 and 6 (3%)/209 (p = 0.07) respectively. CONCLUSIONS: The sub-adventitial divestment technique appeared to be an effective surgical technique to remove the tumor while preserving the artery. This approach warrants further validation in prospective studies.

A novel antisense lncRNA NT5E promotes progression by modulating the expression of SYNCRIP and predicts a poor prognosis in pancreatic cancer.

A novel antisense lncRNA NT5E was identified in a previous microarray that was clearly up-regulated in pancreatic cancer (PC) tissues. However, its biological function remains unclear. Thus, we aimed to explore its function and clinical significance in PC. The lncNT5E expression was determined in PC specimens and cell lines. In vitro and in vivo studies detected the impact of lncNT5E depletion on PC cell proliferation, migration and invasion. Western blotting investigated the epithelial-mesenchymal transition (EMT) markers. The interaction between lncNT5E and the promoter region of SYNCRIP was detected by dual-luciferase reporter assay. The role of lncNT5E in modulating SYNCRIP was investigated in vitro. Our results showed that lncNT5E was significantly up-regulated in PC tissues and cell lines and associated with poor prognosis. LncNT5E depletion inhibited PC cell proliferation, migration, invasion and EMT in vitro and caused tumorigenesis arrest in vivo. Furthermore, SYNCRIP knockdown had effects similar to those of lncNT5E depletion. A significant positive relationship was observed between lncNT5E and SYNCRIP. Moreover, the dual-luciferase reporter assays indicated that lncNT5E depletion significantly inhibited SYNCRIP promoter activity. Importantly, the malignant phenotypes of lncNT5E depletion were rescued by overexpressing SYNCRIP. In conclusion, lncNT5E predicts poor prognosis and promotes PC progression by modulating SYNCRIP expression.

Prognostic Nomogram for Resected Pancreatic Adenocarcinoma: A TRIPOD-Compliant Retrospective Long-Term Survival Analysis.

BACKGROUND: Prognostic prediction had been widely used in various cancer entities, from early screening to end-stage patient caring. Currently, there is hardly any well-validated nomogram which exists for long-term survival prediction in pancreatic adenocarcinoma (PC) patients in a post-surgery setting. Our objectives are to identify possible prognostic factors in PC patients following radical resection and to develop a prognostic nomogram based on independent survival predictors. METHODS: From 2009 to 2014, a total of 432 PC patients who underwent curative intended surgeries with complete follow-up data were included in this current retrospective long-term survival analysis. Clinicopathological data were extracted from medical records, and all missing values (percentage 0.9-8.3%) were imputed five times with the "PMM" method. Cox proportional hazards models were utilized. A nomogram was formulated based on results from the multivariate regression model so as to predict OS at 1-, 2- and 3-year as well as median OS. Validations, including discrimination and calibration, were carried out with 1000 bootstrap resamples. External validation was conducted in order to verify the accuracy of our nomogram at 1 and 2 years by utilizing the clinicopathological data of 122 PC patients who underwent curative intended surgeries in 2015 in our centre. RESULTS: Age, abdominal pain, back pain, tumour location, preoperative neutrophil-lymphocyte ratio, preoperative CA19-9, tumour differentiation, microscopic nerve invasion, microscopic vascular invasion, T stage, lymph node ratio, M stage and adjuvant chemotherapy were all assembled into nomogram. The concordance index (C-index) of internal and external validation was 0.702 and 0.688, respectively. The C-index of the TNM staging system was 0.572 (P < 0.001 vs. nomogram). CONCLUSION: Our prognostic nomogram based on clinicopathological parameters shows good performance in long-term survival prediction in PC patients following radical surgery and could play a role in further clinical utilization.

LncRNA BANCR Promotes Pancreatic Cancer Tumorigenesis via Modulating MiR-195-5p/Wnt/ß-Catenin Signaling Pathway.

Long noncoding BRAF-activated noncoding RNA has been reported to be tightly associated with tumorigenesis and development in various types of cancers. However, the expression, biological function, and modulatory mechanism of BRAF-activated noncoding RNA in pancreatic cancer remained unclear. In the present work, we explored the carcinogenic activity and underlying mechanism of BRAF-activated noncoding RNA on pancreatic cancer in vitro. We identified that BRAF-activated noncoding RNA was upregulated in pancreatic cancer tissues and cell lines, and BRAF-activated noncoding RNA was related to tumor metastasis and stage. BRAF-activated noncoding RNA reinforces proliferation, invasion, and migration in PANC-1 and SW1990 cells. Moreover, miR-195-5p was downregulated in both PC tissues and cell lines. Our results based on luciferase reporter, RIP-Ago2 and qRT-PCR assays, showed that miR-195-5p was a direct target of BRAF-activated noncoding RNA. Furthermore, miR-195-5p inhibitor abrogated the effects of short-interfering BRAF-activated noncoding RNA on PANC-1 and SW1990 cell growth and invasion in vitro. We further identified that BRAF-activated noncoding RNA played a vital role in activating the Wnt/ß-catenin pathway by sponging miR-195-5p. Collectively, our study showed that BRAF-activated noncoding RNA promotes pancreatic cancer tumorigenesis through miR-195-5p/Wnt/ß-catenin axis may serve as a potential target for diagnostics and therapeutics in pancreatic cancer.

The RNA m6A methyltransferase METTL3 promotes pancreatic cancer cell proliferation and invasion.

Epigenetic modifications are involved in carcinogenesis and METTL3 is involved in RNA methylation. This study aimed to explore the role of the RNA m6A methyltransferase METTL3 in pancreatic cancer cells. The m6A modification was analyzed in human pancreatic cancer and paracancerous specimens, as well as in the normal HPDE6-C7 pancreatic cell line and the MIA-PaCa-2 and BxPC-3 pancreatic cancer cell lines. Immunohistochemistry (IHC), western blotting, and RT-qPCR were used to detect the expression of METTL3. Cell lines were transfected with siRNAs against METLL3. Proliferation, invasion, and migration were examined. The functions of METTL3 were predicted by bioinformatics analysis. In the 40 patients included, high METTL3 expression was associated with high pathological stage (P = 0.02) and high N stage (P = 0.02). Survival was better in patients with low METTL3 expression compared with those with high MTTL3 expression (P < 0.01). METTL3 and CIITA expression levels were inversely correlated (r = -0.71, P < 0.01). RNA m6A content in tumor specimens was significantly higher than that in paracancerous specimens. METTL3 protein and mRNA levels were significantly higher in tumor specimens compared with paracancerous specimens, as well as in cancerous cell lines vs. normal cells. METTL3 knockdown in MIA PaCa-2 and BxPC-3 cells decreased RNA m6A modifications. Cell proliferation, invasion, and migration were decreased by METTL3 knockdown in cancerous cell lines. A total of 673 differentially expressed genes were identified by bioinformatics: 659 were upregulated and 14 were downregulated. In conclusion, METTL3 is probably involved in pancreatic carcinogenesis. It could eventually be a prognostic marker or a treatment target.

Parenchyma Preserving Surgery for Idiopathic Chronic Calcific Pancreatitis in Children: A Report of Three Cases.

Background: Idiopathic chronic calcific pancreatitis is a rare entity. Early surgical intervention and a parenchyma sparing procedure should be advocated to prevent further decay of the pancreas and the occurrence of cancer. Case Presentations: Case 1: A 14-year-old boy presented with a 3-year history of right upper abdominal pain that has been aggravated in the last 2 months. Imaging revealed a dilated pancreatic duct of 6 mm with pancreatic duct stones in the head of pancreas. He underwent a Frey's procedure. Unfortunately, he was discharged with grade B pancreatic fistula. Case 2: A 12-year-old boy presented with a 1-year history of dull and recurring epigastric pain. Imaging studies showed multiple stones in a 12 mm dilated pancreatic duct. The patient underwent a modified Puestow procedure. Up to the 42th month follow-up, the patient had no pain complaints. Case 3: A 12-year-old boy with a 1-week history of a dull epigastric pain presented with with multiple stones in a 10 mm duct. He underwent a modified Puestow procedure and was discharged with alleviated pain. Conclusions: "Conservative" surgery allows satisfactory pancreatic duct drainage, reduced rehospitalizations, and longer pain relief than alternative endoscopic procedures.