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.

Prognostic impact of tumour-infiltrating lymphocytes and cancer-associated fibroblasts in patients with pancreatic adenocarcinoma of the body and tail undergoing resection.

BACKGROUND: The prognosis of patients with pancreatic cancer remains poor and novel therapeutic targets are required urgently. Treatment resistance could be due to the tumour microenvironment, a desmoplastic stroma consisting of cancer-associated fibroblasts and tumour-infiltrating lymphocytes (TILs). The aim of the study was to evaluate the prognostic value of TILs and cancer-associated fibroblasts (CAFs) in pancreatic cancer of the body and tail. METHODS: Using tissue microarray from resected left-sided pancreatic cancer specimens, the immunohistochemistry of TILs (cluster of differentiation (CD) 45, CD3, CD4, FoxP3 and CD8), CAFs (vimentin and α-smooth muscle actin (αSMA)) and functional markers (PD-L1 and Ki-67) was examined, and the association with disease-free (DFS) and overall (OS) survival investigated using a computer-assisted quantitative analysis. Patients were classified into two groups, with low or high levels or ratios, using the 75th percentile value as the cut-off. RESULTS: Forty-three patients were included in the study. Their median DFS and OS were 9 and 27 months respectively. A high CD4/CD3 lymphocyte ratio was associated with poorer DFS (8 months versus 11 months for a low ratio) (hazard ratio (HR) 2·23, 95 per cent c.i. 1·04 to 4·61; P = 0·041) and OS (13 versus 27 months respectively) (HR 2·62, 1·11 to 5·88; P = 0·028). A low αSMA/vimentin ratio together with a high CD4/CD3 ratio was correlated with poorer outcomes. No significant association was found between Ki-67, PD-L1 and survival. CONCLUSION: In patients with resected left-sided pancreatic cancer, a tumour microenvironment characterized by a high CD4/CD3 lymphocyte ratio along with a low αSMA/vimentin ratio is correlated with poorer survival.

ANTECEDENTES: El pronóstico del cáncer de páncreas sigue siendo malo y se requieren nuevas dianas terapéuticas de forma urgente. La resistencia al tratamiento podría ser atribuida al microambiente tumoral, un estroma desmoplásico compuesto por fibroblastos asociados al cáncer y linfocitos infiltrantes de tumor. El objetivo del estudio fue evaluar el valor pronóstico de los linfocitos infiltrantes de tumor y de los fibroblastos asociados al cáncer en el cáncer de cuerpo y cola de páncreas. MÉTODOS: Utilizando microarray para el análisis de muestras de tejido obtenidas tras la resección de cáncer de páncreas del lado izquierdo, se realizó inmunohistoquímica de linfocitos infiltrantes de tumor (CD45, CD3, CD4, FoxP3 y CD8), fibroblastos asociados al cáncer (vimentina y actina del músculo liso alfa (αSMA)) y marcadores funcionales (PD-L1 y Ki67), y se investigó la asociación con la supervivencia libre de enfermedad y la supervivencia global. Los resultados se obtuvieron tras un análisis cuantitativo asistido por ordenador. Los pacientes se clasificaron en dos grupos, de bajo y alto riesgo, utilizando el valor del percentil 75 como punto de corte. RESULTADOS: Se incluyeron 43 pacientes en el estudio. En esta población, la mediana de supervivencia libre de enfermedad y de supervivencia global fueron 9 meses y 27 meses, respectivamente. Una alta proporción de linfocitos CD4/CD3 se asoció a peor supervivencia libre de enfermedad (8 meses versus 11 meses; cociente de riesgos instantáneos, hazard ratio, HR 2,2; i.c. del 95% 1,0-4,6; P = 0,041) y supervivencia global (13 meses versus 27 meses; HR 2,6; i.c. del 95% 1,1-5,9; P = 0.028). Una baja proporción αSMA/vimentina junto con una alta proporción CD4/CD3 se correlacionó con peores resultados. No se encontró asociación significativa entre Ki67, PD-L1 y la supervivencia. CONCLUSIÓN: En pacientes con cáncer de páncreas izquierdo resecado, un microambiente tumoral caracterizado por una alta proporción de linfocitos CD4/CD3 junto con una baja proporción de αSMA/vimentina se correlaciona con una peor supervivencia.

'Peripheric' pancreatic cysts: performance of CT scan, MRI and endoscopy according to final pathological examination.

OBJECTIVE: To assess the accuracy of pre-operative staging in patients with peripheral pancreatic cystic neoplasms (pPCNs). METHODS: From 2005 to 2011, 148 patients underwent a pancreatectomy for pPCNs. The pre-operative examination methods of computed tomography (CT), magnetic resonance imaging (MRI), endoscopic ultrasonography (EUS) were compared for their ability to predict the suggested diagnosis accurately, and the definitive diagnosis was affirmed by pathological examination. RESULTS: A mural nodule was detected in 34 patients (23%): only 1 patient (3%) had an invasive pPCN at the final histological examination. A biopsy was performed in 79 patients (53%) during EUS: in 55 patients (70%), the biopsy could not conclude a diagnosis; the biopsy provided the correct and wrong diagnosis in 19 patients (24%) and 5 patients (6%), respectively. A correct diagnosis was affirmed by CT, EUS and pancreatic MRI in 60 (41%), 103 (74%) and 80 (86%) patients (when comparing EUS and MRI; P = 0.03), respectively. The positive predictive values (PPVs) of CT, EUS and MRI were 70%, 75% and 87%, respectively. CONCLUSIONS: Pancreatic MRI appears to be the most appropriate examination to diagnose pPCNs accurately. EUS alone had a poor PPV. Mural nodules in a PCN should not be considered an indisputable sign of pPCN invasiveness.

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.

Ruptured liver cell adenoma in man: great fortune in misfortune.

Liver cell adenoma is mostly known as a tumour affecting women with long-term use of contraceptive hormones. Its incidence in men is very low, and particularly few cases of acute complications are related in the literature. We report the case of a 44-year-old man presenting with a life-threatening rupture of a hepatic tumour, successfully treated in emergency with primary endovascular embolization, followed by hepatectomy, once stabilized. The pathological findings were fortunately consistent with the diagnosis of liver-cell adenoma. To our knowledge, it is the first case reported in a man treated by a combined interventional radiological and surgical approach.

The value of 18F-FDG positron emission tomography to differentiate benign from malignant intraductal papillary mucinous neoplasms: A prospective multicenter study.

OBJECTIVE: To assess the value of 18F-FDG PET/CT in differentiating between benign and malignant intraductal papillary mucinous neoplasms (IPMN) of the pancreas. SUMMARY BACKGROUND DATA: Malignant or high-risk IPMN require surgical resection but surgery should be avoided in patients with IPMN carrying a low risk of malignancy. 18F-FDG PET has been studied mostly in small, single center, retrospective series. METHODS: Prospective, non-comparative, multicenter French study. The primary endpoint was the specificity of PET/CT for identifying malignant IPMN (in situ or invasive carcinoma). Final diagnosis was obtained from pathological examination of the resected specimen. RESULTS: Among 120 patients analyzed, 99 had confirmed IPMN, including 24 with malignant lesions, namely 9 with carcinoma in situ and 15 with invasive carcinoma. The 18F-FDG PET/CT was positive in 44 and 31 patients in the overall and IPMN populations respectively. In the 99 IPMN patients, PET/CT showed 13 true positive, 18 false positive, 57 true negative and 11 false negative results. The sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) for the diagnosis of malignancy were 54.2%, 76.0%, 83.8% and 41.9% respectively, versus 64.9%, 75.9%, 82.9% and 54.5% in the overall population. We could not identify a cut-off value for SUVmax to distinguish benign from malignant lesions. Conventional imaging included computed tomography, magnetic resonance cholangiopancreatography and endoscopic ultrasound. In IPMN patients who underwent the 3 techniques, sensitivity, specificity, NPV and PPV were 66.7%, 84.4%, 84.4% and 66.7% respectively. CONCLUSIONS: In this study, 18F-FDG PET/CT did not perform better than conventional imaging to differentiate malignant from benign IPMN.

Aggressive multimodal therapy of sporadic malignant insulinoma can improve survival: a retrospective 35-year study of 12 patients.

AIM: Sporadic malignant insulinoma (SMI) is a rare disease, and the consequent paucity of data in the literature and the development of aggressive treatments for liver metastases have led us to retrospectively analyze a series of 12 cases of SMI. METHODS: Every patient presenting with SMI, according to the WHO 2004 histopathology criteria, between 1970 and June 2005 in Marseille was included in the study. Patients with multiple endocrine neoplasia type 1 (MEN-1) and tumours of uncertain malignant potential were excluded. RESULTS: The ratio of male/female was 4/8, and mean age at diagnosis was 52.5 years. A 48-h fasting test in 10 patients was conclusive in nine, after a mean duration of 12 h 45 min. SMI size ranged from 7-120 mm (mean 30.3mm). Six patients had liver metastases and one had isolated lymph-node invasion. Surgery was performed in 12 patients. Five persisting diseases (mean follow-up of 1.8 years) required other treatments (chemoembolization, radiofrequency thermoablation [RFTA], liver transplantation); one patient relapsed 8.5 years after surgery; six were still in complete remission (mean follow-up of 5.8 years), and one patient had died by the time of the 24-month follow-up. CONCLUSION: Aggressive sequential multimodal therapy can prolong the survival of patients with SMI even in the presence of liver metastases.

[Endoscopic management of postoperative pancreatic collections]. / Prise en charge endoscopique des collections pancréatiques postopératoires.

INTRODUCTION: Treatment of pancreatic postoperative collections are usually managed with a multidisciplinary team. Different managements are possible: abstention, external drainage, endoscopic treatment or surgery. METHODS: We report on a case series of five patients with a postoperative pancreatic collection, endoscopically managed. Patients underwent all a CT scan associated or not with endoscopic ultrasonography. RESULTS: An endoscopic cystenterosotomy was performed in all the cases, with two double pig tail stents sometimes associated with nasocystic drainage for clearing the cyst lumen and with transpapillary drainage in one case. All the procedures were successful and patients healed in all the cases with the disappearance of the radiological image within a 33 days to three months range with one complication due to superinfection of the drained cyst, endoscopically managed with a nasocystic catheter. CONCLUSION: Therapeutic endoscopy, with a multidisciplinary approach, is a promising way to manage postoperative pancreatic collections.

Risk factors of exocrine and endocrine pancreatic insufficiency after pancreatic resection: A multi-center prospective study.

Management of functional consequences after pancreatic resection has become a new therapeutic challenge. The goal of our study is to evaluate the risk factors for exocrine (ExoPI) and endocrine (EndoPI) pancreatic insufficiency after pancreatic surgery and to establish a predictive model for their onset. PATIENTS AND METHODS: Between January 1, 2014 and June 19, 2015, 91 consecutive patients undergoing pancreatoduodenectomy (PD) or left pancreatectomy (LP) (72% and 28%, respectively) were followed prospectively. ExoPI was defined as fecal elastase content<200µg per gram of feces while EndoPI was defined as fasting glucose>126mg/dL or aggravation of preexisting diabetes. The volume of residual pancreas was measured according to the same principles as liver volumetry. RESULTS: The ExoPI and EndoPI rates at 6 months were 75.9% and 30.8%, respectively. The rate of ExoPI after PD was statistically significantly higher than after LP (98% vs. 21%; P<0.001), while the rate of EndoPI was lower after PD vs. LP, but this difference did not reach statistical significance (28% vs. 38.5%; P=0.412). There was no statistically significant difference in ExoPI found between pancreatico-gastrostomy (PG) and pancreatico-jejunostomy (PJ) (100% vs. 98%; P=1.000). Remnant pancreatic volume less than 39.5% was predictive of ExoPI. CONCLUSION: ExoPI occurs quasi-systematically after PD irrespective of the reconstruction scheme. The rate of EndoPI did not differ between PD and LP.

Resectable pancreatic head adenocarcinoma: Is R0 resection an illusion? Genetic evaluation of venous resection margin affirmed unrecognized disease.

PURPOSE: To assess the K-ras gene mutation in the histologically negative venous margin of a pancreaticoduodenectomy (PD) specimen and its impact on survival. METHOD: From 2007 to 2010, 22 patients underwent R0 PD for resecable pancreatic adenocarcinoma. All specimens were stained and the portal vein (PV) bed was identified by blue ink; a 2mm3 sample (including the blue ink) was cut from a microscopic free-tumor block. DNA was extracted and assessed by quantitative real time polymerase chain reaction to detect the K-ras gene mutation. Twelve specimens (55%) (kras+ group) were identified with a K-ras mutation in the venous margin resection, and 10 specimens (kras- group) did not have K-ras mutation detected in the venous margin resection. RESULTS: The two groups were comparable. Overall 3years survival of patients of kras+ group versus patients of kras- group was 0 and 17% (P=0.03), respectively. Median survival time of patients of kras+ group versus patients of kras- group was 16months vs 25months (P=0.04; 95% confidence interval [1,11-1,88]), respectively. CONCLUSION: Genetic evaluation of venous resection margin affirmed unrecognized disease with strong impact on survival in more than 50% of patients with histologically R0 resection.

Long term morbidity of neoadjuvant chemoradiation for pancreatic head adenocarcinoma.

PURPOSE: To report the long term risks of neoadjuvant chemoradiation (NCRT) after duodenopancreatectomy (DP) for adenocarcinoma of the head of pancreas. METHODS: Between January 1996 and December 2002, 26 patients with biopsy-proven adenocarcinoma of the head of pancreas were treated by this combination of therapies. RESULTS: Two patients had delayed NCRT-related small bowel infarction: one died from superior mesenteric artery stenosis 36 months after DP without recurrence at laparotomy; there was one limited infarction 16 months after DP. CONCLUSIONS: Long term vascular morbidity after NCRT is significant.

Late postpancreatectomy hemorrhage: Predictive factors of morbidity and mortality after percutaneous endovascular treatment.

PURPOSE: The objective of this study was to evaluate the effectiveness of endovascular treatment in patients presenting with late hemorrhage after pancreatectomy (LPPH). MATERIAL AND METHOD: Between 2008 and 2012, 53 percutaneous arterial procedures were performed in 42 patients with LPPH. There were 27 men and 15 women (mean age, 61.8 years±14.5 [SD]; range: 19-81 years). Clinical and technical success along with frequency of complications associated with the use of different endovascular techniques in patients with and without arterial anatomical variation were assessed. RESULTS: Clinical success was observed in 35/42 patients (85%). The technical success was 37.5% in patients with anatomical variation versus 82.8% for those with modal anatomy (P=0.003). Repeat bleeding (P=0.029), complications (P=0.013) and mortality (P=0.045) were more frequent in patients with variation of celiac artery than in those with modal anatomy. For hepatic and gastroduodenal artery stump bleeding, the rate of complications was higher (60%) in the group treated by hepatic artery embolization (P=0.028) by comparison with gastroduodenal artery stump selective embolisations or treatments by covered stent. A significant difference in mortality rate was found between patients with anatomical variations of celiac artery (36.4%) and those with normal anatomy (6.5%) (P=0.032). CONCLUSION: Percutaneous endovascular treatment is effective in patients presenting with LPPH. The presence of an anatomical variation of the celiac artery increases the rate of complications and mortality in patients with LPPH.

Tributyltin triggers apoptosis in trout hepatocytes: the role of Ca2+, protein kinase C and proteases.

The purpose of the present study was to study the mechanisms involved in the induction of apoptosis and by tributyltin (TBT) in rainbow trout hepatocytes, and to examine the role of intracellular Ca2+, protein kinase C (PKC) and proteases in the apoptotic process. The intracellular Ca2+ chelator BAPTA-AM has a suppressive effect on TBT-mediated apoptosis. However, exposure to the ionophore A23187 is not sufficient to induce apoptosis in trout hepatocytes. The results obtained also show that TBT stimulates PKC gamma and delta translocation from cytosol to the plasma membrane in trout hepatocytes after 30 min of exposure. However, PKC gamma translocation is down-regulated after 90 min of treatment. The addition of protein kinase inhibitors (staurosporine and H-7) not only fails to inhibit apoptosis induced by TBT, but also leads to enhancement of DNA fragmentation. These inhibitors also afford a remarkable protection against the loss of plasma membrane integrity caused by TBT exposure. PMA, a direct activator of PKC, fails to stimulate DNA fragmentation. In addition, Z-VAD.FMK is an extremely potent inhibitor of TBT-induced apoptosis in trout hepatocytes, indicating that the activation of ICE-like proteases is a key event in this process. The cysteine protease inhibitor N-ethylmaleimide also prevented TBT-induced DNA fragmentation. Taken together, these data allow for the first time to suggest a mechanistic model of TBT-induced apoptosis. We propose that TBT could trigger apoptosis through a step involving Ca2+ efflux from the endoplasmic reticulum or other intracellular pools and by mechanisms involving cysteine proteases, such as calpains, as well as the phosphorylation status of apoptotic proteins such as Bcl-2 homologues.

Rectus abdominis myocutaneous flap in radical oncopelvic surgery: a safe and useful procedure.

AIMS: The aim of this retrospective study was to evaluate the usefulness of rectus abdominis myocutaneous (RAM) flaps to treat locally advanced pelvic gynaecological or digestive tumours. METHODS: We reviewed 46 patients, who received RAM flaps after radical oncopelvic surgery, including: (a) total vaginal reconstruction (TVR); (b) partial vaginal reconstruction (PVR); (c) perineal reconstruction (PR). RESULTS: Between 1989 and 1998, 46 patients underwent pelvi-perineal reconstruction with RAM flaps after radical pelvic surgery for carcinoma of the cervix (n=22), anal carcinoma (n=11), rectal carcinoma (n=7), or other pelvic tumours types (n=6). There were two post-operative deaths. Overall surgical morbidity was 45, 6% (n=21). Specific morbidity of the RAM flap was 21, 7% (n=10). Global re-intervention rate was 13% (n=6). CONCLUSION: Rectus abdominis myocutaneous flap in radical oncopelvic surgery is useful for vaginal or perineal reconstruction and prevention of pelvic collections after extended resections with a low rate of associated morbidity.

The oncological safety of laparoscopic total mesorectal excision with sphincter preservation for rectal carcinoma.

BACKGROUND: Although experience of laparoscopic treatment of rectal carcinoma has been reported, there is no evidence of its oncological safety because most procedures included partial mesorectal excision or abdominoperineal excision and quality of surgery is lacking. The aim of this study was to assess the oncological results of laparoscopic total mesorectal excision with sphincter preservation for rectal carcinoma. METHODS: From 2000 to 2003, 144 patients underwent laparoscopic total mesorectal excision with low colorectal or coloanal anastomosis for mid and low rectal adenocarcinoma. There were 88 men and 56 women, with a median age of 65 years. The tumor was located at 5.5 cm (range 1-12) from the anal verge and was classified uT1T2 in 25 cases and uT3 in 119 cases. One hundred twenty patients received preoperative radiotherapy. RESULTS: Postoperative mortality and morbidity were 1% and 34% respectively. Conversion was 14% (n = 20). Macroscopic assessment of the specimen (n = 92) showed an intact mesorectum in 88% of the cases. The distal margin and the circumferential margin were safe in 98% and 94% of the cases, respectively. A complete microscopic excision, i.e., R0 resection, was achieved in 134 cases (93%). Pathological data were similar to those of an open match group. With a median follow-up of 18 months, there was no port-site recurrence and two patients had local recurrence (1.4%). The 3-year overall and disease- free survival rates were 89% and 77%, respectively. CONCLUSIONS: A high quality of surgical excision can be achieved by the laparoscopic dissection, suggesting that this approach in treatment of rectal carcinoma is oncologically safe.

[Major hepatectomy for metastasis of colorectal cancer improves survival in the elderly]. / Hépatectomie majeure pour métastases de cancers colorectaux chez le sujet âgé.

OBJECTIVE: Assessing impact of major liver resection (LR) for hepatic metastasis of colorectal cancer (HMCC) on post operative courses and long term survival in the elderly. PATIENTS AND METHOD: Thirty-three consecutive patients aged over 70 years-old were treated in our institution for up to 3 resectable metachronous HMCC. Fifteen patients had major LR (9 right hepatectomy, 3 extended right hepatectomy, 3 left hepatectomy) without pre or postoperative chemotherapy (group 1) and 18 patients were exclusively treated by chemotherapy (group 2) because of high ASA score (ASA 3) or patients refusal. RESULTS: No patients died of another cause that colorectal cancer disease during observation time. All patients of group 2 died during observation time. Post operative mortality and morbidity of group 1 were respectively 0% and 33%. Survival at 1 and 2 years of group 1-2 were respectively 73-50% (P=0,04) and 47-15% (P=0,05). Median survival of group 1 and 2 were respectively 22 and 12 months (P=0,03). CONCLUSIONS: Major LR for HMCC could be proposed regardless the age. High ASA score, multiple (more than 4) metastasis location, evolutive disease could justify an exclusive medical approach.

Stromal SLIT2 impacts on pancreatic cancer-associated neural remodeling.

Pancreatic ductal adenocarcinoma (PDA) is a critical health issue in the field of cancer, with few therapeutic options. Evidence supports an implication of the intratumoral microenvironment (stroma) on PDA progression. However, its contribution to the role of neuroplastic changes within the pathophysiology and clinical course of PDA, through tumor recurrence and neuropathic pain, remains unknown, neglecting a putative, therapeutic window. Here, we report that the intratumoral microenvironment is a mediator of PDA-associated neural remodeling (PANR), and we highlight factors such as 'SLIT2' (an axon guidance molecule), which is expressed by cancer-associated fibroblasts (CAFs), that impact on neuroplastic changes in human PDA. We showed that 'CAF-secreted SLIT2' increases neurite outgrowth from dorsal root ganglia neurons as well as from Schwann cell migration/proliferation by modulating N-cadherin/ß-catenin signaling. Importantly, SLIT2/ROBO signaling inhibition disrupts this stromal/neural connection. Finally, we revealed that SLIT2 expression and CAFs are correlated with neural remodeling within human and mouse PDA. All together, our data demonstrate the implication of CAFs, through the secretion of axon guidance molecule, in PANR. Furthermore, it provides rationale to investigate the disruption of the stromal/neural compartment connection with SLIT2/ROBO inhibitors for the treatment of pancreatic cancer recurrence and pain.

Differences in hypolipidaemic effects of two statins on Hep G2 cells or human hepatocytes in primary culture.

1. The objective of this study was to compare in cultured human hepatocytes or Hep G2 cells, changes in the fate of unesterified low density lipoprotein (LDL)-cholesterol induced by crilvastatin, a new cholesterol lowering drug and a reference statin, simvastatin. 2. The experiments were carried out for 20 h, each well contained 4.2 x 10(5)/cm2 Hep G2 cells or 0.5 x 10(5)/Cm2 human hepatocytes, 130 microM ursodeoxycholate, 0.68 microCi or 1.59 microCi unesterified human [14C]-LDL-cholesterol, crilvastatin or simvastatin at 0 or 50 microM (both cell types) or 300 microM (Hep-G2 cells). Incubation with the two drugs resulted in increased amounts of unesterified [14C]-LDL-cholesterol taken by the two cell types, compared to control. 3. Crilvastatin 50 microM led to significantly higher quantities of [14C]-glyco-tauro-conjugated bile salts, compared to simvastatin. Statins reduced the apo B100 level secreted by the two cell types (simvastatin) or human hepatocytes (crilvastatin). Crilvastatin enhanced both the level of apo A1 secreted by the Hep G2 cells and the level of APF, a high density lipoprotein (HDL) and biliary apoprotein. 4. Crilvastatin not only acts by stimulating LDL-cholesterol uptake by hepatocytes, but also by enhancing the catabolism of LDL-cholesterol in bile salts and probably by stimulating HDL and/or bile component secretion. Such a mechanism was not previously described for HMG CoA reductase inhibitors. Our results on APF show that this apoprotein could be considered also as an indicator of changes in bile and/or HDL compartments. 5. The human hepatocyte model appeared to be a suitable and relevant model in the pharmacological-metabolic experiments carried out in this study. It led to more consistent data than those obtained with Hep G2 cells.