Modulation of Human Peripheral Blood Mononuclear Cell Signaling by Medicinal Cannabinoids.

Medical marijuana is increasingly prescribed as an analgesic for a growing number of indications, amongst which terminal cancer and multiple sclerosis. However, the mechanistic aspects and properties of cannabis remain remarkably poorly characterized. In this study we aimed to investigate the immune-cell modulatory properties of medical cannabis. Healthy volunteers were asked to ingest medical cannabis, and kinome profiling was used to generate comprehensive descriptions of the cannabis challenge on inflammatory signal transduction in the peripheral blood of these volunteers. Results were related to both short term and long term effects in patients experimentally treated with a medical marijuana preparation for suffering from abdominal pain as a result of chronic pancreatitis or other causes. The results reveal an immunosuppressive effect of cannabinoid preparations via deactivation of signaling through the pro-inflammatory p38 MAP kinase and mTOR pathways and a concomitant deactivation of the pro-mitogenic ERK pathway. However, long term cannabis exposure in two patients resulted in reversal of this effect. While these data provide a powerful mechanistic rationale for the clinical use of medical marijuana in inflammatory and oncological disease, caution may be advised with sustained use of such preparations.

DNA integrity as biomarker in pancreatic cyst fluid.

Identification of pancreatic cysts with malignant potential is important to prevent pancreatic cancer development. Integrity of cell free DNA (cfDNA) has been described as tumor biomarker, but its potential for pancreatic cancer is unclear. While normal apoptotic cells release uniformly truncated DNA, malignant tissues release long fragments of cell free DNA (cfDNA). We measured 247 base pair (bp) and 115 bp DNA fragments of ALU repeats by qPCR in serum from healthy controls and pancreatic cancer patients, and in cyst fluid from pancreatic cyst patients. No differences in total cfDNA (ALU115) and cfDNA integrity (ALU247/115) were observed between sera from healthy controls (n=19) and pancreatic cancer patients (n=19). Although elevated as compared to serum, but no differences in cfDNA were found in cyst fluid from high risk (n=10) and low risk (n=20) cyst patients. We conclude that cfDNA integrity is not a useful marker to identify (pre)malignant pancreatic lesions.

Cytopathological Analysis of Cyst Fluid Enhances Diagnostic Accuracy of Mucinous Pancreatic Cystic Neoplasms.

Widespread use of cross-sectional imaging and increasing age of the general population has increased the number of detected pancreatic cystic lesions. However, several pathological entities with a variety in malignant potential have to be discriminated to allow clinical decision making. Discrimination between mucinous pancreatic cystic neoplasms (PCNs) and nonmucinous pancreatic lesions is the primary step in the clinical work-up, as malignant transformation is mostly associated with mucinous PCN. We performed a retrospective analysis of all resected PCN in our tertiary center from 2000 to 2014, to evaluate preoperative diagnostic performance and the results of implementation of the consensus guidelines over time. This was followed by a prospective cohort study of patients with an undefined pancreatic cyst, where the added value of cytopathological mucin evaluation to carcinoembryonic antigen (CEA) in cyst fluid for the discrimination of mucinous PCN and nonmucinous cysts was investigated. Retrospective analysis showed 115 patients operated for a PCN, with a correct preoperative classification in 96.2% of the patients. High-grade dysplasia or invasive carcinoma was observed in only 32.3% of mucinous PCN. In our prospective cohort (n = 71), 57.7% of patients were classified as having a mucinous PCN. CEA ≥ 192 ng/mL had an accuracy of 63.4%, and cytopathological mucin evaluation an accuracy of 73.0%. Combining these 2 tests further improved diagnostic accuracy of a mucinous PCN to 76.8%. CEA level and mucin evaluation were not predictive of the degree of dysplasia. These findings show that adding cytopathology to cyst fluid biochemistry improves discrimination between mucinous PCN and nonmucinous cysts.

Dichotomal effect of space flight-associated microgravity on stress-activated protein kinases in innate immunity.

Space flight strongly moderates human immunity but is in general well tolerated. Elucidation of the mechanisms by which zero gravity interacts with human immunity may provide clues for developing rational avenues to deal with exaggerated immune responses, e.g. as in autoimmune disease. Using two sounding rockets and one manned Soyuz launch, the influence of space flight on immunological signal transduction provoked by lipopolysaccharide (LPS) stimulation was investigated in freshly isolated peripheral blood monocytes and was compared to samples obtained from on-board centrifuge-loaded 1 g controls. The effect of microgravity on immunological signal transduction is highly specific, since LPS dependent Jun-N-terminal kinase activation is impaired in the 0 g condition, while the corresponding LPS dependent activation of p38 MAP kinase remains unaffected. Thus our results identify Jun-N-terminal kinase as a relevant target in immunity for microgravity and support using Jun-N-terminal kinase specific inhibitors for combating autoimmune disease.

mTOR is a promising therapeutical target in a subpopulation of pancreatic adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal disease, unusually resistant against therapy. It is generally felt that stratification of patients for personalized medicine is the way forward. Here, we report that a subpopulation of PDACs shows strong activation of the mTOR signaling cassette. Moreover, we show that inhibition of mTOR in pancreatic cancer cell lines showing high levels of mTOR signaling is associated with cancer cell death. Finally, we show using fine needle biopsies the existence of a subpopulation of PDAC patients with high activation of the mTOR signaling cassette and provide evidence that inhibition of mTOR might be clinically useful for this group. Thus, our results define an unrecognized subpopulation of PDACs, characterized by high activation of mTOR and show that identification of this specific patient group in the early phase of diagnosis is feasible.

Predictors of in-hospital mortality and 6-month functional outcomes in older adults after moderate to severe traumatic brain injury.

INTRODUCTION: Traumatic brain injury (TBI) is the single largest cause of death and disability following injury worldwide. While TBI in older adults is less common, it still contributes to significant morbidity and mortality in this group. Understanding the patient characteristics that result in good and poor outcome after TBI is important in the clinical management and prognosis of older adult TBI patients. This population-based study investigated predictors of mortality and longer term functional outcomes following serious TBI in older adults. METHODS: All older adults (aged>64 years), isolated moderate to severe TBI cases from the population-based Victorian State Trauma Registry for the period July 2005 to June 2007 (inclusive) were extracted for analysis. Demographic, injury event, injury diagnosis, management and comorbid status information were obtained and the outcomes of interest were in-hospital mortality, and the Glasgow Outcome Scale-Extended (GOS-E) score at 6 months post-injury. Multivariate logistic regression analyses were used to identify independent predictors of in-hospital mortality and independent living (GOS-E>4) status at 6 months. RESULTS: Of the 428 isolated, older adult TBI cases, the majority were the result of a fall (88%), male (55%), and aged>74 years (76%). The in-hospital death rate was 28% and increasing age (p=0.009), decreasing GCS (p<0.001) and injury type (p=0.002) were significant independent predictors of in-hospital mortality. Of the 310 patients who survived to discharge, 65% were successfully followed-up 6 months following injury. There was no difference between patients lost to follow-up and those successfully followed-up with respect to the key population indicators of age, gender, or head injury severity. Younger (<75 years) patients, and those with an SBP on arrival at hospital of 131-150mmHg, were at increased odds of living independently at follow-up. No patients with a GCS<9 had a good 6-month outcome, and most of them died. The survival rate for brainstem injury was also low (21%). CONCLUSION: In this population-based study, we found that age, GCS, brainstem injury, and systolic blood pressure were the most important factors in predicting outcome in older adults with an isolated moderate to severe TBI.