Step-up approach for the treatment of infected necrotising pancreatitis: real life data from a single-centre experience with long-term follow-up.

BACKGROUND: About 20% of patients with acute pancreatitis develop a necrotising form with a worse prognosis due to frequent appearance of organ failure(s) and/or infection of necrosis. Aims of the present study was to evaluate the "step up" approach treatment of infected necrosis in terms of: feasibility, success in resolving infection, morbidity of procedures, risk factors associated with death and long-term sequels. METHODS: In this observational retrospective monocentric study in the real life, necrotizing acute pancreatitis at the stage of infected walled-off necrosis were treated as follow: first step with drainage (radiologic and/or endoscopic-ultrasound-guided with lumen apposing metal stent); in case of failure, minimally invasive necrosectomy sessions(s) by endoscopy through the stent and/or via retroperitoneal surgery (step 2); If necessary open surgery as a third step. Efficacy was assessed upon to a composite clinical-biological criterion: resolution of organ failure(s), decrease of at least two of clinico-biological criteria among fever, CRP serum level, and leucocytes count). RESULTS: Forty-one consecutive patients were treated. The step-up strategy: (i) was feasible in 100% of cases; (ii) allowed the infection to be resolved in 33 patients (80.5%); (iii) Morbidity was mild and rapidly resolutive; (iv) the mortality rate at 6 months was of 19.5% (significant factors: SIRS and one or more organ failure(s) at admission, fungal infection, size of the largest collection ≥ 16 cm). During the follow-up (median 72 months): 27% of patients developed an exocrine pancreatic insufficiency, 45% developed or worsened a previous diabetes, 24% had pancreatic fistula and one parietal hernia. CONCLUSIONS: Beside a very good feasibility, the step-up approach for treatment of infected necrotizing pancreatitis in the real life displays a clinico-biological efficacy in 80% of cases with acceptable morbidity, mortality and long-term sequels regarding the severity of the disease.

Curative surgical treatment of common bile duct stones: Retrospective cohort study.

BACKGROUND: In the event of symptomatic common bile duct (CBD) stones with dilated CBD, one possible curative treatment option is stone extraction through choledocotomy associated with cholecystectomy. Endoscopic treatment is only reserved for residual stones at 6 weeks. The aim of this study was to evaluate the results from laparoscopic curative surgical treatment of CBD stones with dilated CBD. METHODS: This is a retrospective single-centered cohort study. All consecutive patients admitted for laparoscopic cholecystectomy with evidence of CBD stones with dilated CBD from January 2010 to December 2020 at our center were included. Success was defined by CBD clearance at 6 weeks. Need for additional procedures, such as endoscopic sphincterotomy, immediate, and end-of-procedure morbi-mortality as well as factors associated with procedure failure, were also studied. RESULTS: A total of 246 patients who received curative treatment were included in the study. The success rate for the curative treatment was 93.1% (229 patients). Immediate postoperative morbidity was 24.4% with a 5.3% reintervention rate. Immediate and 6-week postoperative mortality rates were zero and 0.4%, respectively. The mean length of stay was 11.3 days. Factors associated with procedure failure appeared to be the occurrence of an early postoperative complication and the need for readmission during the period between surgery and drain removal. CONCLUSION: This study indicates that laparoscopic curative surgical treatment for symptomatic CBD stones may be performed with acceptable results without routine need for additional procedures.

Minute virus of mice shows oncolytic activity against pancreatic cancer cells exhibiting a mesenchymal phenotype.

Pancreatic cancer will soon become the second cause of death by cancer in Western countries. The main barrier to increase the survival of patients with this disease requires the development of novel and efficient therapeutic strategies that better consider tumor biology. In this context, oncolytic viruses emerge as promising therapeutics. Among them, the fibrotropic minute virus of mice prototype (MVMp) preferentially infects migrating and undifferentiated cells that highly resemble poorly differentiated, basal-like pancreatic tumors showing the worst clinical outcome. We report here that MVMp specifically infects, replicates in, and kills pancreatic cancer cells from murine and human origin with a mesenchymal, basal-like profile, while sparing cancer cells with an epithelial phenotype. Remarkably, MVMp infection, at a dose that does not provoke tumor growth inhibition in athymic mice, shows significant antitumoral effect in immune-competent models; extended mouse survival; and promoted the massive infiltration of tumors by innate, myeloid, and cytotoxic T cells that exhibit a less terminally exhausted phenotype. Collectively, we demonstrate herein for the first time that MVMp is specific and oncolytic for pancreatic tumors with mesenchymal, basal-like profile, paving the way for precision-medicine opportunities for the management of the most aggressive and lethal form of this disease.

Chymotrypsin activity signals to intestinal epithelium by protease-activated receptor-dependent mechanisms.

BACKGROUND AND PURPOSE: Chymotrypsin is a pancreatic protease secreted into the lumen of the small intestine to digest food proteins. We hypothesized that chymotrypsin activity may be found close to epithelial cells and that chymotrypsin signals to them via protease-activated receptors (PARs). We deciphered molecular pharmacological mechanisms and gene expression regulation for chymotrypsin signalling in intestinal epithelial cells. EXPERIMENTAL APPROACH: The presence and activity of chymotrypsin were evaluated by Western blot and enzymatic activity tests in the luminal and mucosal compartments of murine and human gut samples. The ability of chymotrypsin to cleave the extracellular domain of PAR1 or PAR2 was assessed using cell lines expressing N-terminally tagged receptors. The cleavage site of chymotrypsin on PAR1 and PAR2 was determined by HPLC-MS analysis. The chymotrypsin signalling mechanism was investigated in CMT93 intestinal epithelial cells by calcium mobilization assays and Western blot analyses of (ERK1/2) phosphorylation. The transcriptional consequences of chymotrypsin signalling were analysed on colonic organoids. KEY RESULTS: We found that chymotrypsin was present and active in the vicinity of the colonic epithelium. Molecular pharmacological studies have shown that chymotrypsin cleaves both PAR1 and PAR2 receptors. Chymotrypsin activated calcium and ERK1/2 signalling pathways through PAR2, and this pathway promoted interleukin-10 (IL-10) up-regulation in colonic organoids. In contrast, chymotrypsin disarmed PAR1, preventing further activation by its canonical agonist, thrombin. CONCLUSION AND IMPLICATIONS: Our results highlight the ability of chymotrypsin to signal to intestinal epithelial cells via PARs, which may have important physiological consequences in gut homeostasis.

Cytidine Deaminase Resolves Replicative Stress and Protects Pancreatic Cancer from DNA-Targeting Drugs.

Cytidine deaminase (CDA) functions in the pyrimidine salvage pathway for DNA and RNA syntheses and has been shown to protect cancer cells from deoxycytidine-based chemotherapies. In this study, we observed that CDA was overexpressed in pancreatic adenocarcinoma from patients at baseline and was essential for experimental tumor growth. Mechanistic investigations revealed that CDA localized to replication forks where it increased replication speed, improved replication fork restart efficiency, reduced endogenous replication stress, minimized DNA breaks, and regulated genetic stability during DNA replication. In cellular pancreatic cancer models, high CDA expression correlated with resistance to DNA-damaging agents. Silencing CDA in patient-derived primary cultures in vitro and in orthotopic xenografts in vivo increased replication stress and sensitized pancreatic adenocarcinoma cells to oxaliplatin. This study sheds light on the role of CDA in pancreatic adenocarcinoma, offering insights into how this tumor type modulates replication stress. These findings suggest that CDA expression could potentially predict therapeutic efficacy and that targeting CDA induces intolerable levels of replication stress in cancer cells, particularly when combined with DNA-targeted therapies. SIGNIFICANCE: Cytidine deaminase reduces replication stress and regulates DNA replication to confer resistance to DNA-damaging drugs in pancreatic cancer, unveiling a molecular vulnerability that could enhance treatment response.