Relevance of biopsy-derived pancreatic organoids in the development of efficient transcriptomic signatures to predict adjuvant chemosensitivity in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) patients are frequently treated by chemotherapy. Even if personalized therapy based on molecular analysis can be performed for some tumors, PDAC regimens selection is still mainly based on patients' performance status and expected efficacy. Therefore, the establishment of molecular predictors of chemotherapeutic efficacy could potentially improve prognosis by tailoring treatments. We have recently developed an RNA-based signature that predicts the efficacy of adjuvant gemcitabine using 38 PDAC primary cell cultures. While demonstrated its efficiency, a significant association with the classical/basal-like PDAC spectrum was observed. We hypothesized that this flaw was due to the basal-like biased phenotype of cellular models used in our strategy. To overcome this limitation, we generated a prospective cohort of 27 consecutive biopsied derived pancreatic organoids (BDPO) and include them in the signature identification strategy. As BDPO's do not have the same biased phenotype as primary cell cultures we expect they can compensate one with each other and cover a broader range of molecular phenotypes. We then obtained an improved signature predicting gemcitabine sensibility that was validated in a cohort of 300 resected PDAC patients that have or have not received adjuvant gemcitabine. We demonstrated a significant association between the improved signature and the overall and disease-free survival in patients predicted as sensitive and treated with adjuvant gemcitabine. We propose then that including BDPO along primary cell cultures represent a powerful strategy that helps to overcome primary cell cultures limitations producing unbiased RNA-based signatures predictive of adjuvant treatments in PDAC.

A transcriptomic signature to predict adjuvant gemcitabine sensitivity in pancreatic adenocarcinoma.

BACKGROUND: Chemotherapy is the only systemic treatment approved for pancreatic ductal adenocarcinoma (PDAC), with a selection of regimens based on patients' performance status and expected efficacy. The establishment of a potent stratification associated with chemotherapeutic efficacy could potentially improve prognosis by tailoring treatments. PATIENTS AND METHODS: Concomitant chemosensitivity and genome-wide RNA profiles were carried out on preclinical models (primary cell cultures and patient-derived xenografts) derived from patients with PDAC included in the PaCaOmics program (NCT01692873). The RNA-based stratification was tested in a monocentric cohort and validated in a multicentric cohort, both retrospectively collected from resected PDAC samples (67 and 368 patients, respectively). Forty-three (65%) and 203 (55%) patients received adjuvant gemcitabine in the monocentric and the multicentric cohorts, respectively. The relationships between predicted gemcitabine sensitivity and patients' overall survival (OS) and disease-free survival were investigated. RESULTS: The GemPred RNA signature was derived from preclinical models, defining gemcitabine sensitive PDAC as GemPred+. Among the patients who received gemcitabine in the test and validation cohorts, the GemPred+ patients had a higher OS than GemPred- (P = 0.046 and P = 0.00216). In both cohorts, the GemPred stratification was not associated with OS among patients who did not receive gemcitabine. Among gemcitabine-treated patients, GemPred+ patients had significantly higher OS than the GemPred-: 91.3 months [95% confidence interval (CI): 61.2-not reached] versus 33 months (95% CI: 24-35.2); hazard ratio 0.403 (95% CI: 0.221-0.735, P = 0.00216). The interaction test for gemcitabine and GemPred+ stratification was significant (P = 0.0245). Multivariate analysis in the gemcitabine-treated population retained an independent predictive value. CONCLUSION: The RNA-based GemPred stratification predicts the benefit of adjuvant gemcitabine in PDAC patients.

Different shades of pancreatic ductal adenocarcinoma, different paths towards precision therapeutic applications.

BACKGROUND: Different histological and molecular subtypes of pancreatic ductal adenocarcinoma (PDAC), with different molecular composition and survival statistics, have recently been recognised. MATERIALS AND METHODS: This review describes the currently available studies regarding molecular and histological subtypes in PDAC. Studies from major cohorts such as International Cancer Genome Consortium as well as smaller cohorts are reviewed. We discuss where the described subtypes overlap, where the discrepancies are and which paths forward could be taken regarding diagnosis, ontogeny and therapy. RESULTS: Four molecular subtypes with strong overlap among the different studies can be found, next to a list of mixed findings. Two of the four subtypes (epithelial classical and mesenchymal basal-like) were represented in every study and were often discriminated in other solid tumours as well. These two subtypes differ substantially in prognosis. One biomarker has been discovered, only discriminating these two subtypes, and insights into subtype-specific therapeutic vulnerabilities are scarce. CONCLUSION: Subtypes can be reproducibly detected in cohorts of PDAC patients and two of them directly relate with prognosis. A consensus on the subtypes is warranted. Further discovery and validation studies are needed to identify strong biomarkers, to comprehend subtype ontogeny and to define strategies for precision medicine.

WITHDRAWN: A single center experience in resectable pancreatic ductal adenocarcinoma : the limitations of the surgery-first approach. Critical review of the literature and proposals for practice update.

The article has been withdrawn at the request of the authors and editor because of incorrect authorship, which is considered a form of unethical publication. The Publisher apologizes for any inconvenience this may cause.

A single center experience in resectable pancreatic ductal adenocarcinoma : the limitations of the surgery-first approach. Critical review of the literature and proposals for practice update.

BACKGROUND AND STUDY AIMS: The current standard of care for resectable pancreatic ductal adenocarcinoma (PDAC) is surgery-first followed by adjuvant chemotherapy. We review our single center experience in a PDAC cohort managed by the surgery-first strategy. We then compare our data to those of Belgian and international literature. PATIENTS METHODS: We reviewed a series of 83 consecutive resectable patients with PDAC, treated by the surgery-first approach in a Belgian Academic Hospital between 2007 and 2013. The outcomes were assessed with univariate and multivariate Cox regression analysis. Kaplan-Meier curves were drawn according to patient groups. RESULTS: For the entire population, the median survival (MS) was 18.4 months; the 1-year relapse-free survival was 56%, and the 5-year overall survival (OS) was 13%. The size of the primary tumor larger than 3 cm (OS, HR = 1.76, p = 0.033) and vascular resection (DFS, HR = 2.1, p = 0.024) were the single independent prognostic factors in the multivariate analysis of this cohort. Only 69% of the patients received adjuvant chemotherapy, and more than 75% of them demonstrated no chance of survival beyond 3 years because they harbored poor prognostic factors, recognized only postoperatively. CONCLUSIONS: Our results and those published in the literature brought to light the limited perspectives of the surgery-first strategy in a population of apparently resectable pancreatic cancers. In comparison, data from reported neo-adjuvant series deserve our interest to bring this strategy upfront in selected patients in the context of close observational monitoring and randomized trials. The actual standard of care for resectable PDAC is surgery-first followed by adjuvant chemotherapy. The performance of this strategy relies on the dedicated imaging that does not accurately recognize the limits of the tumor and the high prevalence of adverse prognostic factors. Moreover, pancreatectomy remains associated with high postoperative complication rates and the poor completion of adjuvant therapy. This translates into poor long-term survival figures. In our series the MS was 18.4 months and 5-year OS was 13%. The disease-free survival (DFS) was 15.6 months, 1 and 3-year DFS were 56 and 26%, respectively. The variables that significantly correlated with OS in univariate analysis are tumor size and lymph node involvement. Regarding DFS, vascular resection was the only significant factor. In the multivariate analysis, the only significant factor related to OS remained the tumor size >3 cm in greatest diameter. Vascular resection remained significant for DFS. 31% of the patients did not receive any chemotherapy at all before the 6-month period following resection. The rates of complete resections compared favorably with those of a surgery-first strategy with no excess of operative mortality, complications and early relapse rates. The advantages of a chemotherapy-first approach, eventually combined with chemo-radiotherapy, are to offer higher combined therapy completion rates and improve the level of free resection margins, lymph node involvement and patient selection. The advent of safe, more potent chemotherapy combinations has the potential to further improve survival when administered upfront.

DLL4 expression is a prognostic marker and may predict gemcitabine benefit in resected pancreatic cancer.

BACKGROUND: There is an increasing interest for Notch signalling pathway and particularly Delta-like ligand 4 (DLL4) as potential therapeutic target to improve outcome for patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: Using immunohistochemistry (IHC) and tissue microarray (TMA), we assessed the expression patterns of DLL4, Notch1 and Notch3 in 151 patients from two independent cohorts of resected PDAC. We investigated the prognostic and the predictive significance of these proteins. RESULTS: High IHC DLL4 expression in cancer cells was associated with worse overall survival (OS) and disease-free survival (DFS) than low DLL4 expression (median OS: 12.9 vs 30.4 months, P=0.004 and median DFS: 8.8 vs 17.4 months, P=0.02). High DLL4 expression remained a significant negative prognostic factor in multivariate analysis (HR for OS: 2.1, P=0.02 and HR for DFS: 2.0, P=0.02). Low DLL4 abundance was associated with a longer OS-only for patients who received an adjuvant gemcitabine-based chemotherapy (P<0.001) but not for patients who did not receive gemcitabine (P=0.72). Furthermore, the interaction test for adjuvant gemcitabine therapy was statistically significant (P<0.001). The validating cohort recapitulated the findings of the training cohort. CONCLUSIONS: Low DLL4 abundance in tumour cells may predict the benefit from adjuvant gemcitabine therapy after PDAC resection.

[Evolution in the therapeutic strategy of localized resectable pancreatic ductal adenocarcinoma]. / Evolution dans la prise en charge de l'adénocarcinome du pancréas localisé estimé résécable.

Pancreatic ductal adenocarcinoma is characterized by a high rate of early metastatic relapse. Surgical resection is still recognized as the cornerstone upfront therapy. However, reported 5 years survival rates are inferior to 20-25% even when surgery is followed by chemotherapy. Margins involvement on the surgical specimen (50 to 85%) and lymph node involvement (around 70%) both strongly impact survival. Median survivals are close to those of locally advanced diseases treated by chemotherapy or chemoradiotherapy, 15 to 16 months. This review focuses on adverse prognostic factors, post-operative outcomes and their impact on multimodality therapy completion rates and survivals in patients undergoing upfront surgery. Current data and emerging results from neoadjuvant series could lead to a change in the therapeutic strategy.

Effect of alpha-1-blockade by prazosin on blood sugar, insulin and glucagon levels in normals and non-insulin dependent diabetics.

The AA. studied the glycometabolic activity of prazosin, a hypotensive drug with an adrenergic blocking activity of alpha-1-selective type. Twenty-two moderately hypertensive subjects were studied. Their ages ranged from 37 to 57 years; 10 of the patients had non-insulin dependent diabetes mellitus. After overnight fasting every patient underwent an oral glucose test (g 100) at 09:00. Blood samples were withdrawn at 0, 30, 60, 90 and 120 minutes. Each patient was then given in randomized and double-blind fashion placebo or prazosin (4 mg, 2 pills of Minipress Pfizer per day) for the following 7 days; then another glucose load was administered. Glucose (enzymatic method), insulin and glucagon (RIA method) were measured in each blood sample. In non diabetic subjects glucose levels (60, 90, 120 min and total area) after oral glucose and prazosin were statistically higher (p less than 0.05, p less than 0.01, p less than 0.05) than after glucose only. No significant difference between the two curves was observed in the diabetic group. IRI levels in normal subjects were statistically higher after 120 min and in the total area, while no evident changes were noted in the diabetic group. The glucagon curve seen after oral glucose was not modified by prazosin in either group.

[Rapid effect of glucuronyl glucosamine glycan sulfate on the blood levels of HDL-cholesterol in vascular diseases]. / Effetto rapido del glucuronilglucosamin-glicano solfato sui livelli ematici di HDL-colesterolo in vasculopatici.

The Authors investigated on the main lipidemic parameters in vascular diseases after acute administration of glucuronyl-glucosamine-glycan sulfate (3GS). The study was carried out in 48 subjects, aged 33 to 78, of whom 38 males and 10 females so divided: 6 metabolically healthy controls (N), 10 with vascular cerebral disease (VCD), 15 with coronary heart disease, 17 with peripheral vascular disease (PVD). Each subject, fasting and without drug treatment at least since 14 hours, after venous blood withdrawal, was given endovenous rapid bolus of 570 lipasemic units of glucuronyl-glucosamine-glycan sulfate (3GS); after 10', 20' and 30' other blood samples were taken; plasma NEFA (colorimetric method) triglycerides (TG), total cholesterol (TC) and HDL-cholesterol (C-HDL) (enzyme method) were assayed; C-HDL/TC ratio was calculated and LDL-cholesterol value (C-LDL) according to the Friedwald-Fredrickson's formula was obtained. In controls NEFA increase after 20' (+ 57%) and triglycerides drop (-49%) were detected; TC significant fall (-13%, P less than 0,05) after 20' was found, preceded by both C-HDL marked increase and C-HDL/TC ratio, and followed (30') by C-LDL slight rise. In the 3 groups of vascular patients a striking NEFA increase (respectively + 50%, + 43%, + 26%) was found; in subjects with PVD/TG blunted drop was observed, whereas in VCD and in CHD TG percentage fall -41 and -44%) did not differ from that one of controls. Evident remarked in control, drop of total cholesterolemia, lacked in the 3 groups of vascular diseases; in patients with VCD and PVD C-HDL and C-HDL/TC ratio increasing profile was like normal, while in CHD both progressive reduction of C-HDL (-19% after 30') and C-HDL/TC ratio with C-LDL increase were appreciated. On the basis of their results the Authors believed that in PVD a striking deficit of total plasma lipoprotein lipase (LPL), already in vitro documented, may occur, whereas LPL resulted normal in VCD and in CHD; on the contrary, in CHD an abnormally cholesterol-apo-VLDL affinity, like metabolic atherogenic derangement, was found; in the 3 groups of vascular diseases slow peripheral cholesterol removal was detectable.