Rintatolimod: a potential treatment in patients with pancreatic cancer expressing Toll-like receptor 3.

Pancreatic cancer has a dismal prognosis, and treatment options for patients with locally advanced or metastatic disease are limited. Early tumor progression after standard chemo- and or radiotherapy remains a major concern in managing these patients. Treating pancreatic cancer patients with the Toll-like receptor 3 (TLR-3) agonist rintatolimod (Ampligen®) was effective in boosting the immune response. Rintatolimod acts via the TLR-3 receptor on several immune cells. However, the TLR-3 expression pattern in pancreatic cancer cells and how rintatolimod affects pancreatic cancer cells have not yet been investigated. The TLR-3 protein and mRNA expression were evaluated in thirteen PDAC tissue samples as well as in the human PDAC (hPDAC) cell lines CFPAC-1, MIAPaCa-2, and PANC-1 using immunohistochemistry and multiplexed gene expression analysis, respectively. The direct anti-tumor effects of rintatolimod were investigated using a proliferation and migration assay after different incubation time points with increasing concentrations of rintatolimod (ranging from 0.05 to 0.4 mg/ml). The TLR-3 protein and mRNA expression were heterogeneous between the PDAC tissue samples and the three hPDAC cell lines. TLR-3 protein and mRNA expression were high in CFPAC-1, moderate in MIAPaCa-2, and undetectable in PANC-1. Rintatolimod three-day treatment resulted in significantly reduced proliferation of CFPAC-1 cells compared to vehicle-treated control cells. In addition, after 24 hours, rintatolimod-treated CFPAC-1 cells showed less cell migration compared to vehicle-treated control cells, although this difference was not statistically significant. Lastly, we identified fifteen genes, altered with a Log2 FOC > |1.0| in rintatolimod-treated CFPAC-1 cells, which were significantly related to three transcription factors (NFKB1, RELA, and SP1) regulating the TLR-3 signaling pathway. In conclusion, we propose that rintatolimod treatment might have a direct TLR-3-dependent anti-tumoral effect on pancreatic cancer cells expressing TLR-3.

Comparison of lumen-apposing metal stents versus double-pigtail plastic stents for infected necrotising pancreatitis.

OBJECTIVE: Lumen-apposing metal stents (LAMS) are believed to clinically improve endoscopic transluminal drainage of infected necrosis when compared with double-pigtail plastic stents. However, comparative data from prospective studies are very limited. DESIGN: Patients with infected necrotising pancreatitis, who underwent an endoscopic step-up approach with LAMS within a multicentre prospective cohort study were compared with the data of 51 patients in the randomised TENSION trial who had been assigned to the endoscopic step-up approach with double-pigtail plastic stents. The clinical study protocol was otherwise identical for both groups. Primary end point was the need for endoscopic transluminal necrosectomy. Secondary end points included mortality, major complications, hospital stay and healthcare costs. RESULTS: A total of 53 patients were treated with LAMS in 16 hospitals during 27 months. The need for endoscopic transluminal necrosectomy was 64% (n=34) and was not different from the previous trial using plastic stents (53%, n=27)), also after correction for baseline characteristics (OR 1.21 (95% CI 0.45 to 3.23)). Secondary end points did not differ between groups either, which also included bleeding requiring intervention-5 patients (9%) after LAMS placement vs 11 patients (22%) after placement of plastic stents (relative risk 0.44; 95% CI 0.16 to 1.17). Total healthcare costs were also comparable (mean difference -€6348, bias-corrected and accelerated 95% CI -€26 386 to €10 121). CONCLUSION: Our comparison of two patient groups from two multicentre prospective studies with a similar design suggests that LAMS do not reduce the need for endoscopic transluminal necrosectomy when compared with double-pigtail plastic stents in patients with infected necrotising pancreatitis. Also, the rate of bleeding complications was comparable.

Patients with chronic mesenteric ischemia have an altered sublingual microcirculation.

BACKGROUND: Little is known about the microcirculatory alterations in patients with chronic mesenteric ischemia (CMI). We hypothesized that patients with CMI have an impaired microcirculatory function and show an oral microcirculatory response after caloric challenge compared to healthy controls. METHODS: All patients and controls received the standard workup for CMI. Sublingual micro-circulation was evaluated before (T0) and 20 minutes after (T1) feeding. The total vessel density (TVD; mm/mm2), perfused vessel density (PVD; mm/mm2), proportion of perfused vessels (PPV; %) and microvascular flow index (MFI; AU) were assessed. RESULTS: We included 12 patients (63.2 years [IQR 48.8-70.4 years], 67% males) and 12 controls (32.7 years [IQR 27.7-38.1 years], 42% males). At baseline, patients with CMI had a decreased PPV of the sublingual small vessels (median 84.8% vs 95.7%, P=0.006), PPV of all vessels (PPV median 85.4% vs 95.3%, P=0.007) and microvascular flow index of all vessels (MFIa; median 3.00 vs 2.80, P=0.039) compared to healthy controls. After caloric challenge, PVD increased significantly in both small vessels (perfused vessel density of the small vessels [PVDs]) and all vessels (perfused vessel density of all vessels [PVDa]; PVDs [T0]) median 16.3 [IQR 13.3-22.1] vs [T1] median 19.9 [IQR 14.2-26.2], P=0.008; PVDa [T0] median 19.1 [IQR 16.2-23.6] vs [T1] median 22.2 [IQR 16.5-28.9], P=0.02; proportion of perfused vessels of the small vessels (PPVs; [T0] median 84.8% [IQR 75.3-90.4] vs [T1] median 91.0% [IQR 80.1-93.8], P=0.010). In contrast, no significant changes in microcirculatory parameters were observed after caloric challenge in healthy controls. CONCLUSION: Patients with CMI have an impaired sublingual microcirculation at baseline and show a significant response in the sublingual microcirculation after caloric challenge, whereas healthy controls have a normal microcirculation at baseline and show no reactive response upon a caloric challenge as seen in CMI patients. Sublingual microcirculation visualization may offer a rapid noninvasive method to identify patients at risk for having CMI.

IFN-ß is a potent inhibitor of insulin and insulin like growth factor stimulated proliferation and migration in human pancreatic cancer cells.

INTRODUCTION: Pancreatic cancer is a highly aggressive malignancy with few treatment options. The overexpression of several growth factors, including insulin and insulin-like growth factors (IGFs), can underlie the aggressive nature of this disease. Previous research has demonstrated potent effects of interferon (IFN)-ß on pancreatic cancer cell growth, however up till now it is unknown whether IFN-ß is able to counteract IGF1, IGF2 and insulin-induced pancreatic cancer cell proliferation and migration. METHODS: Expression of IGF- and insulin receptors was determined and the stimulatory effects of IGF1, IGF2 and insulin on cell proliferation and migration, as well as the inhibitory effects of IFN-ß were evaluated in 3 human pancreatic adenocarcinoma cell lines. RESULTS: Both the insulin- and the IGF1 receptor were variably expressed in the cell lines. IGF1, IGF2 and insulin were capable of stimulating cell proliferation in all three cell lines, however cell migration was significantly enhanced only in the BxPC-3 cell line. IFN-ß significantly inhibited IGF1-, IGF2- and insulin-stimulated proliferation in all three cell lines in a dose and time dependent manner. Furthermore, in the BxPC-3 cell line IFN-ß significantly inhibited both basal and IGF1-, IGF2- and insulin-stimulated cell migration. CONCLUSION: Both IGF1, -2 and insulin were capable of stimulating proliferation and migration in human pancreatic cancer cells irrespective of the type of receptor expressed. This study demonstrates that insulin, in addition to IGF1 and IGF2, may play an important role in the progression of pancreatic cancer. Moreover, IFN-ß strongly inhibits growth factor stimulated cell proliferation and migration. Our study supports previous findings which have suggested that IFN-ß can be a potential promising anti-cancer agent in pancreatic cancer.

Circulating DNA and Micro-RNA in Patients with Pancreatic Cancer.

Collecting repeat samples of blood ("liquid biopsies") is a broadly used clinical approach for serial monitoring of disease or response to treatments. In patients with cancer the most distinct molecular feature are somatic mutations acquired by cancer cells present in the diseased tissue. Indeed, mutant DNA derived from dying or lysed cancer cells can be isolated from patient serum samples, subjected to DNA sequencing and to analysis of abundance as a measure of tumor burden. Also, changes in the DNA mutation patterns in serum samples collected over time can indicate altered pathways or clonal evolution of the disease and altered abundance of mutant DNA suggests an altered disease burden. In addition, during the course of treatment, changes in circulating DNA mutation patterns can indicate the emergence of resistant clones and prompt changes in treatment. In contrast to mutant DNA, microRNAs (miR) are transcribed, processed, packaged and released from cells in normal and in diseased tissues as part of the extracellular crosstalk between cells. Interestingly, released miR can function in cell-to-cell communication and as hormone-like signals that operate at a distance through their release into the circulation and subsequent uptake into cells in distant tissues. Circulating miR expression patterns can be established from serial serum samples and monitored for alterations over time. Circulating miR provide a readout of the organism's steady state and serial analyses will indicate changes in the response to therapy or an altered physiologic or disease state. Furthermore, changes in circulating miR patterns can indicate treatment efficacy or resistance as well as adverse effects associated with the respective intervention. Thus, the combined serial analysis of mutant DNA and miR in the circulation has the potential to provide a molecular footprint of pancreatic cancer and can be used to monitor treatment responses or resistance to treatment in real time with a minimally invasive procedure.

Probiotic prophylaxis in predicted severe acute pancreatitis: a randomised, double-blind, placebo-controlled trial.

BACKGROUND: Infectious complications and associated mortality are a major concern in acute pancreatitis. Enteral administration of probiotics could prevent infectious complications, but convincing evidence is scarce. Our aim was to assess the effects of probiotic prophylaxis in patients with predicted severe acute pancreatitis. METHODS: In this multicentre randomised, double-blind, placebo-controlled trial, 298 patients with predicted severe acute pancreatitis (Acute Physiology and Chronic Health Evaluation [APACHE II] score > or =8, Imrie score > or =3, or C-reactive protein >150 mg/L) were randomly assigned within 72 h of onset of symptoms to receive a multispecies probiotic preparation (n=153) or placebo (n=145), administered enterally twice daily for 28 days. The primary endpoint was the composite of infectious complications--ie, infected pancreatic necrosis, bacteraemia, pneumonia, urosepsis, or infected ascites--during admission and 90-day follow-up. Analyses were by intention to treat. This study is registered, number ISRCTN38327949. FINDINGS: One person in each group was excluded from analyses because of incorrect diagnoses of pancreatitis; thus, 152 individuals in the probiotics group and 144 in the placebo group were analysed. Groups were much the same at baseline in terms of patients' characteristics and disease severity. Infectious complications occurred in 46 (30%) patients in the probiotics group and 41 (28%) of those in the placebo group (relative risk 1.06, 95% CI 0.75-1.51). 24 (16%) patients in the probiotics group died, compared with nine (6%) in the placebo group (relative risk 2.53, 95% CI 1.22-5.25). Nine patients in the probiotics group developed bowel ischaemia (eight with fatal outcome), compared with none in the placebo group (p=0.004). INTERPRETATION: In patients with predicted severe acute pancreatitis, probiotic prophylaxis with this combination of probiotic strains did not reduce the risk of infectious complications and was associated with an increased risk of mortality. Probiotic prophylaxis should therefore not be administered in this category of patients.