Activation of PGC-1α via isoliquiritigenin-induced downregulation of miR-138-5p alleviates nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD), a metabolic disease, has received wide attention worldwide. However, there is no approved effective drug for NAFLD treatment. In the study, H&E and Oil Red O staining were employed to detect liver histopathological changes and the accumulation of lipid droplets. Quantitative real-time PCR, Western blot, bioinformatics, luciferase assay, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to further elucidate the mechanism of isoliquiritigenin (ISL) against NAFLD. The results showed that ISL significantly reduced the liver-to-body weight ratios and biochemical index. And the staining results showed that ISL remarkedly ameliorated liver histopathological changes of NAFLD. Furthermore, ISL significantly increased the levels of PPARα, CPT1α, and ACADS, which were involved in lipid metabolism, and inhibited the ROS, TNF-α, IL-1ß, and IL-6 expression by activating PGC-1α. Bioinformatics and luciferase assay analysis confirmed that miR-138-5p might bind to PGC-1α mRNA in NAFLD. Importantly, the expression of miR-138-5p was increased in the NAFLD, which was significantly decreased by ISL. In addition, the miR-138-5p inhibitor also promoted lipid metabolism and inhibited inflammatory response in NAFLD via PGC-1α activation. The above results demonstrate that ISL alleviates NAFLD through modulating miR-138-5p/PGC-1α-mediated lipid metabolism and inflammatory reaction in vivo and in vitro.

Perineural invasion is related to p38 mitogen-activated protein kinase pathway activation and promotes tumor growth and chemoresistance in pancreatic cancer.

Metastasis is a key component of cancer progression and is strongly associated with poor prognosis. Perineural invasion is thought to be related to pain, tumor recurrence, and other conditions. However, the exact molecular mechanism is unclear. This study was conducted to identify the key components and signaling pathways involved in the perineural invasion of pancreatic cancer and alterations in the phenotype after the interaction between the dorsal root ganglion (DRG) and pancreatic cancer cells. The results indicated that the p38 mitogen-activated protein kinase signaling pathway was activated after coculture of the DRG and pancreatic cancer cells and lead to the promotion of cell growth and chemoresistance.

Resection of pancreatic metastatic renal cell carcinoma: experience and long-term survival outcome from a large center in China.

PURPOSE: This study aimed to determine the outcome of pancreatic metastatic renal cell carcinoma (PmRCC) after treatment and share the relevent results. METHODS: In total, 13 patients with PmRCC were diagnosed and treated in our institution from December 2013 to October 2017. We retrospectively reviewed the records and analyzed the patient demographics, perioperative outcomes, and overall survival. Simultaneously, our experience including treatment and misdiagnosis was shared. RESULTS: The median time between nephrectomy and reoperation for pancreatic recurrence was 11 years (range 1-20 years). Four patients had multiple tumors and nine patients had solitary tumor. Five patients accepted distal pancreatectomy, and five patients underwent pancreaticoduodenectomy. One patient underwent total pancreatectomy, one patient underwent duodenum-preserving pancreatic head resection plus distal pancreatectomy, and one patient underwent exploratory laparotomy and gastrointestinal bypass due to widespread metastasis with clear obstructive symptoms. The misdiagnosis rate of preoperative diagnosis at our center was 69.2% (9/13). The median follow-up duration was 26 months (range 7-53 months, until June 2018). By the end of follow-up, 12 patients were alive and one patient died of gastrointestinal bleeding within 1 month after surgery. CONCLUSIONS: PmRCCs are uncommon, but pancreatic metastasectomy has a relatively good prognosis and may, therefore, be a good therapeutic choice for patients with PmRCCs. Because PmRCC occurs long after the primary tumor resection, long-term follow-up is necessary. Besides, detailed medical history and specific manifestation in imaging features could contribute to avoiding misdiagnosis.

MicroRNA-300 promotes apoptosis and inhibits proliferation, migration, invasion and epithelial-mesenchymal transition via the Wnt/ß-catenin signaling pathway by targeting CUL4B in pancreatic cancer cells.

The study aims to verify the hypothesis that up-regulation of microRNA-300 (miR-300) targeting CUL4B promotes apoptosis and suppresses proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of pancreatic cancer cells by regulating the Wnt/ß-catenin signaling pathway. Pancreatic cancer tissues and adjacent tissues were collected from 110 pancreatic cancer patients. Expression of miR-300, CUL4B, Wnt, ß-catenin, E-cadherin, N-cadherin, Snail, GSK-3ß, and CyclinD1 were detected using qRT-PCR and Western blot. CFPAC-1, Capan-1, and PANC-1 were classified into blank, negative control (NC), miR-300 mimics, miR-300 inhibitors, siRNA-CUL4B, and miR-300 inhibitors + siRNA-CUL4B groups. The proliferation, migration, invasion abilities, the cell cycle distribution, and apoptosis rates were measured in CCK-8 and Transwell assays. Pancreatic cancer tissues showed increased CUL4B expression but decreased miR-300 expression. When miR-300 was lowly expressed, CUL4B was upregulated which in-turn activated the Wnt/ß-catenin pathway to protect the ß-catenin expression and thus induce EMT. When miR-300 was highly expressed, CUL4B was downregulated which in-turn inhibited the Wnt/ß-catenin pathway to prevent EMT. Weakened cell migration and invasion abilities and enhanced apoptosis were observed in the CUL4B group. The miR-300 inhibitors group exhibited an evident increase in growth rate accompanied the largest tumor volume. Smaller tumor volume and slower growth rate were observed in the miR-300 mimics and siRNA-CUL4B group. Our study concludes that lowly expressed miR-300 may contribute to highly expressed CUL4B activating the Wnt/ß-catenin signaling pathway and further stimulating EMT, thus promoting proliferation and migration but suppressing apoptosis of pancreatic cancer cells.

Farnesoid X receptor overexpression prevents hepatic steatosis through inhibiting AIM2 inflammasome activation in nonalcoholic fatty liver disease.

Oxidative stress-mediated activation of inflammasome has a significant effect on the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Farnesoid X receptor (NR1H4, FXR) has been implicated in biological function and many diseases, including NAFLD. The regulatory effect of FXR on oxidative stress and whether this process is related with the activation of absent melanoma 2 (AIM2) inflammasome in NAFLD remain unclear. In the present research, we confirmed that FXR in the livers of steatosis patients is significantly reduced compared with normal liver tissue by using the Gene Expression Omnibus (GEO) database and a palmitic acid (PA) - mediated steatosis model in AML-12 cells. Under the premise of ensuring the same food intake as the control group, overexpression of FXR in mice attenuated HFD-mediated weight gain and liver steatosis, facilitated lipid metabolism, improved fatty acid ß-oxidation, lipolysis, and reduced fatty acid synthesis and intake, which also inhibited the activation of AIM2 inflammasome. Overexpression of FXR alleviated PA-induced triglyceride (TG) accumulation, imbalance of lipid homeostasis, and the activation of AIM2 inflammasome in hepatic steatosis cells, while FXR knockdown appeared the opposite effects. FXR overexpression suppressed PA- and HFD-induced oxidative stress, but FXR siRNA demonstrated the opposite influence. The decreased ROS generation may be the reason why FXR weakens AIM2 activation when a fatty acid overload occurs. In conclusion, our results confirm that other than regulating lipid homeostasis and blocking NLRP3 inflammasome activation, FXR improves hepatic steatosis by a novel mechanism that inhibits oxidative stress and AIM2 inflammasome activation.

FXR overexpression prevents hepatic steatosis through inhibiting AIM2 inflammasome activation in alcoholic liver disease.

BACKGROUND AND PURPOSE: Alcoholic liver disease (ALD), a metabolic liver disease caused by excessive alcohol consumption, has attracted increasing attention due to its high prevalence and mortality. Up to date, there is no effective and feasible treatment method for ALD. This study was to investigate whether Farnesoid X receptor (FXR, NR1H4) can alleviate ALD and whether this effect is mediated by inhibiting absent in melanoma 2 (AIM2) inflammasome activation. METHODS: The difference in FXR expression between normal subjects and ALD patients was analyzed using the Gene Expression Omnibus (GEO) database. Lieber-DeCarli liquid diet with 5% ethanol (v/v) (EtOH) was adopted to establish the mouse ALD model. Liver histopathological changes and the accumulation of lipid droplets were assessed by H&E and Oil Red O staining. Quantitative real-time PCR, Western blotting analysis and immunofluorescence staining were utilized to evaluate the expression levels of related genes and proteins. DCFH-DA staining was adopted to visualize reactive oxidative species (ROS). RESULTS: FXR was distinctly downregulated in liver tissues of patients with steatosis compared to normal livers using the GEO database, and in ethanol-induced AML-12 cellular steatosis model. FXR overexpression ameliorated hepatic lipid metabolism disorder and steatosis induced by ethanol by inhibiting the expression of genes involved in lipid synthesis and inducing the expression of genes responsible for lipid metabolism. Besides, FXR overexpression inhibited ethanol-induced AIM2 inflammasome activation and alleviated oxidative stress and ROS production during ethanol-induced hepatic steatosis. However, when FXR was knocked down, the results were completely opposite. CONCLUSIONS: FXR attenuated lipid metabolism disorders and lipid degeneration in alcohol-caused liver injury and alleviated oxidative stress and inflammation by inhibiting AIM2 inflammasome activation.

Bruceine A alleviates alcoholic liver disease by inhibiting AIM2 inflammasome activation via activating FXR.

BACKGROUND: Alcoholic liver disease (ALD), a public health challenge worldwide caused by long-term persistent drinking, is life-threatening with minimal approved therapies. Hepatic steatosis accompanied by inflammation is an initial and inevitable stage in the complex progression of simple alcoholic liver injury to more severe liver diseases such as hepatitis, liver fibrosis, cirrhosis and liver cancer. PURPOSE: We aimed to identify the therapeutic role of Bruceine A (BA) in ALD whilst attempting to explore whether its protective effects depend specifically on the farnesoid X receptor (FXR). METHODS: Autodock was applied to detect the affinity between BA and FXR. Lieber-DeCarli liquid diet with 5 % ethanol (v/v) was adopted to establish the mouse ALD model. The lentivirus mediating FXR (LV-FXR) was injected into mice via the tail vein to establish FXR-overexpressed mice. FXR silencing or overexpression plasmids were transfected into AML-12 cells prior to ethanol stimulation. Quantitative real-time PCR, Western blotting and immunofluorescence assays were employed to determine the expression of related genes. We subjected liver sections to H&E and Oil Red O staining to evaluate the liver histological injury and the deposition of lipid droplets. RESULTS: BA significantly reduced body weight and liver-to-body weight ratios as well as biochemical indexes in mice. Ethanol-induced liver damage and lipid accumulation could be alleviated by BA treatment. BA bound to FXR by two hydrogen bonds. There was a positive correlation between BA administration and FXR expression. BA inhibited the expression of lipid synthesis genes and enhanced the expression of lipid metabolism genes by activating FXR, thus alleviating steatosis in ALD. Moreover, BA exerted an ameliorative effect against inflammation by inhibiting the activation of absent in melanoma 2 (AIM2) inflammasome by activating FXR. FXR overexpression possessed the ability to counter the accumulation of lipid and the activation of AIM2 inflammasome caused by ethanol. FXR deficiency exacerbated ethanol-induced liver steatosis and inflammation. The hepatoprotective effect of BA could be disrupted by FXR antagonist guggulsterone (GS) in vivo and FXR siRNA in vitro. CONCLUSION: BA alleviated alcoholic liver disease by inhibiting AIM2 inflammasome activation through an FXR-dependent mechanism. This study may potentially represent a new therapeutic approach for ALD.

Efficacy and complications of inoperable malignant distal biliary obstruction treatment by metallic stents: fully covered or uncovered?

Obstructive jaundice caused by malignant distal biliary obstruction is a common clinical symptom in patients with inoperable biliary-pancreatic cancer. Endoscopic retrograde cholangiopancreatography (ERCP)-guided stent implantation is an effective treatment for obstructive jaundice. Internal stent drainage is more physiologic and associated with a better quality of life than external stent drainage methods such as percutaneous transhepatic gallbladder drainage or percutaneous transhepatic cholangiodrainage. Self-expanding metallic stents, which may be covered and uncovered, are commonly used. However, some uncertainties remain regarding the selection of metallic stents, including drainage patency time, clinical effect, stent migration, and post-operative complications such as pancreatitis, bleeding, and cholecystitis. This review aims to summarize the current progress and controversies surrounding the use of covered or uncovered metallic stents in inoperable common biliary obstruction via ERCP.

Correlation between Macrophage Polarization and PD-L1-Related Tumor Microenvironmental Alteration and Metastasis in Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with a poor prognosis; nearly 80% patients have regional or distant metastasis when diagnosed. Tumor microenvironment (TME) alteration and epithelial-to-mesenchymal transition (EMT) have been reported to play a key role in cancer metastasis. However, the correlation between TME and EMT was poorly studied in PDAC. This study aims to explore the correlation between EMT markers and TME alteration, mainly including macrophage polarization and PD-L1 expression change, in primary and metastatic PDAC tissues by immunohistochemistry. The results indicated that macrophage polarization was found in metastases with the number of M1 macrophages (CD86+) decreased and M2 (CD163+) increased, though PD-L1 expression did not have a significant alteration. Compared to primary tumors, E-cadherin was significantly lower, while snail was higher, while no difference was found with N-cadherin and ZEB1. Correlation analysis indicated that snail, but not ZEB1, E-cadherin, or N-cadherin, was highly correlated with macrophage polarization. To conclude, the number of CD86+ M1 macrophages was increased while CD163+ M2 macrophages decreased in metastases, with no significant alteration of PD-L1 expression compared to primary tumors. EMT markers-Snail and E-cadherin-but not ZEB1 or N-cadherin, were found to be higher/lower in metastases, which mean that EMT played an important role in PDAC metastasis. Further analysis indicated that snail was highly correlated with M1 to M2 macrophage polarization, which prompted that EMT may be one reason for macrophage polarization induced TME alteration in PDAC metastasis.

Neoadjuvant Therapy for Pancreatic Ductal Adenocarcinoma: Where Do We Go?

The incidence of pancreatic ductal adenocarcinoma (PDAC) has been on the rise in recent years; however, its clinical diagnosis and treatment remain challenging. Although surgical resection remains the only chance for long-term patient survival, the likelihood of initial resectability is no higher than 20%. Neoadjuvant therapy (NAT) in PDAC aims to transform the proportion of inoperable PDACs into operable cases and reduce the likelihood of recurrence to improve overall survival. Ongoing phase 3 clinical trial aims to validate the role of NAT in PDAC therapy, including prolongation of survival, increased R0 resection, and a higher proportion of negative lymph nodes. Controversies surrounding the role of NAT in PDAC treatment include applicability to different stages of PDAC, chemotherapy regimens, radiation, duration of treatment, and assessment of effect. This review aims to summarize the current progress and controversies of NAT in PDAC.

ORM 1 as a biomarker of increased vascular invasion and decreased sorafenib sensitivity in hepatocellular carcinoma.

This study aimed to clarify the role of Orosomucoid 1 (ORM1) in the development and therapy resistance in hepatocellular carcinoma (HCC). The mRNA expression level of ORM1 was analyzed via integrative analysis of Gene Express Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets. The protein expression level of ORM1 in our cohort was determined using immunohistochemistry. Correlation analysis was used to investigate the relationship between ORM1 expression and clinical parameters. The Cell Counting Kit-8 assay was used to clarify the role of ORM1 in HCC malignant behaviors, including cell growth and sorafenib sensitivity, in vitro. The results indicated that ORM1 was significantly downregulated in the hepatic cancer cells compared to that in the non-cancerous cells. However, it was upregulated in microvascular invasion samples, especially in the cancer embolus compared to that in the surrounding tumor cells. Though Kaplan-Meier analysis did not show an association of ORM1 expression with the overall survival rates of HCC patients, univariate analysis indicated that ORM1 expression was highly correlated with tumor grade and stage. An in vitro assay also revealed that downregulation of ORM1 led to the suppression of tumor growth and enhancement of sorafenib sensitivity without epithelial-to-mesenchymal transition (EMT) alteration, which was consistent with our bioinformatic analysis. Hence, ORM1 played a key role in HCC tumorigenesis and may serve as a potential target for the development of therapeutics against HCC in the future.

Luteolin ameliorates LPS-induced acute liver injury by inhibiting TXNIP-NLRP3 inflammasome in mice.

BACKGROUND: Chemical liver injury is one of the main causes of acute liver failure and death. To date, however, treatment strategies for acute liver injury have been limited. Therefore, there is an urgent need to find new therapeutic targets and effective drugs. NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome is a complex of multiple proteins that has been shown to induce cell death under inflammatory and stress pathologic conditions and is thought to provide new targets for the treatment of a variety of diseases. PURPOSE: The purpose of this study was to investigate whether luteolin has a protective effect on the liver and further elucidate whether it is realized through the thioredoxin interacting protein (TXNIP)-NLRP3 axis. STUDY DESIGN: Acute hepatic injury in mice caused by intraperitoneal injection of lipopolysaccharide (LPS) was treated with or without luteolin. METHODS: Male C57BL/6 mice and mouse primary hepatocytes were selected. TXNIP protein knockdown was achieved by siRNA, qPCR and Western blot were performed to explore the mechanism of luteolin in alleviating acute liver injury. RESULTS: The results indicated that luteolin had a markedly protective effect on acute liver injury induced by LPS in mice by inhibiting the TXNIP-NLRP3 axis. Luteolin inhibits NLRP3 inflammasome activation by suppressing TXNIP, apoptosis associated speck-like protein containing a CARD domain (ASC), caspase-1, interleukin-1ß (IL-1ß) and IL-18 to reduce liver injury. In addition, luteolin inhibits LPS-induced liver inflammation by inhibiting the production of inflammation-related gene tumor necrosis factor-α (TNF-α), IL-10, and IL-6. What's more, luteolin alleviated LPS-induced hepatocyte injury by inhibiting oxidative stress and regulating MDA, SOD, and GSH levels. However, the protective effect of luteolin on acute LPS-induced liver injury in mice was blocked by si-TXNIP in vitro. CONCLUSIONS: These combined data showed that luteolin may alleviate LPS-induced liver injury through the TXNIP-NLPR3 axis, providing new therapeutic targets and therapeutic drugs for subsequent studies.

Safety and efficacy of S1 monotherapy or combined with nab-paclitaxel in advanced elderly pancreatic cancer patients: A meta-analysis.

OBJECTIVE: To evaluate the therapeutic efficacy and safety of S1 monotherapy or combination with nab-paclitaxel for the treatment of elderly patients with metastatic or locally advanced pancreatic adenocarcinoma. METHOD: PubMed, Embase, Cochrane Central Library, China Biology Medicine, and China National Knowledge Infrastructure databases were searched without time limits according to the inclusion criteria. RevMan (Version 5.3) software was used for data extraction and meta-analysis. Objective response rate (ORR) and disease control rate (DCR) were used to evaluate therapeutic effects while side effects including leukopenia, thrombocytopenia, neurotoxicity, vomit, and alopecia were extracted for evaluation. There was no need for ethical review in this study because no ethical experiments were conducted and all data used were public data. All relevant data are within the paper and its Supporting Information files. RESULTS: Four retrospective studies comprising 308 elderly patients with metastatic or locally advanced pancreatic adenocarcinoma were included in the analysis. One hundred fifty-one patients underwent S1 monotherapy and 157 received S1 combined nab-paclitaxel. Meta-analysis indicated that compared with S1 monotherapy, S1 combined with nab-paclitaxel had higher ORR (OR 2.25, 95% CI: 1.42-3.55; P = .0005) and DCR (OR 2.94, 95% CI: 1.55-5.58; P = .0009). The adverse reaction of leukopenia was higher in the combined therapy group (OR 1.85, 95% CI: 1.09-3.13, P = .02), but no significant difference was found in thrombocytopenia, neurotoxicity, vomiting, and alopecia between the 2 groups (P > .05). CONCLUSION: Nab-paclitaxel plus S1 was more efficient in terms of ORR and DCR than S1 monotherapy in elderly pancreatic ductal adenocarcinoma patients while the side effect was controllable with a higher probability of leukopenia. Thus, combined nab-paclitaxel and S1 could be safely used in elderly patients.

Yangonin modulates lipid homeostasis, ameliorates cholestasis and cellular senescence in alcoholic liver disease via activating nuclear receptor FXR.

BACKGROUND: Alcoholic liver disease (ALD) is a progressive disease beginning with simple steatosis but can progress to alcoholic steatohepatitis, fibrosis, cirrhosis, and even hepatocellular carcinoma. The morbidity of ALD is on the rise and has been a large burden on global healthcare system. It is unfortunately that there are currently no approved therapeutic drugs against ALD. Hence, it is of utmost urgency to develop the efficacious therapies. The ability of many molecular targets against ALD is under investigation. Farnesoid X receptor (FXR), a member of the ligand-activated transcription factor superfamily, has been recently demonstrated to have a crucial role in the pathogenesis and progression of ALD. PURPOSE: The purpose of the study is to determine whether Yangonin (YAN), a FXR agonist previously demonstrated by us, exerts the hepatoprotective effects against ALD and further to clarify the mechanisms in vitro and in vivo. STUDY DESIGN: The alcoholic liver disease model induced by Lieber-Decarli liquid diet was established with or without Yan treatment. METHODS: We determined the liver to body weight ratios, the body weight, serum and hepatic biochemical indicators. The alleviation of the liver histopathological progression was evaluated by H&E and immunohistochemical staining. Western blot and quantitative real-time PCR were used to demonstrate YAN treatment-mediated alleviation mechanisms of ALD. RESULTS: The data indicated that YAN existed hepatoprotective activity against ALD via FXR activation. YAN improved the lipid homeostasis by decreasing hepatic lipogenesis and increasing fatty acid ß-oxidation and lipoprotein lipolysis through modulating the related protein. Also, YAN ameliorated ethanol-induced cholestasis via inhibiting bile acid uptake transporter Ntcp and inducing bile acid efflux transporter Bsep and Mrp2 expression. Besides, YAN improved bile acid homeostasis via inducing Sult2a1 expression and inhibiting Cyp7a1 and Cyp8b1 expression. Furthermore, YAN attenuated ethanol-triggered hepatocyte damage by inhibiting cellular senescence marker P16, P21 and Hmga1 expression. Also, YAN alleviated ethanol-induced inflammation by down-regulating the inflammation-related gene IL-6, IL-1ß and TNF-α expression. Notably, the protective effects of YAN were cancelled by FXR siRNA in vitro and FXR antagonist GS in vivo. CONCLUSIONS: YAN exerted significant hepatoprotective effects against liver injury triggered by ethanol via FXR-mediated target gene modulation.

Establishment and Investigation of a Multiple Gene Expression Signature to Predict Long-Term Survival in Pancreatic Cancer.

Pancreatic cancer remains a lethal type of cancer with poor prognosis. Molecular classification enables in-depth, precise prognostic assessment. This study is aimed at identifying a robust and simple mRNA signature to predict the overall survival (OS) of pancreatic cancer (PC) patients. Differentially expressed genes (DEGs) between 45 paired pancreatic tumor samples and adjacent healthy tissues were selected. For risk determination, a LASSO Cox regression model with DEGs was used to generate the OS-associated risk score formula for the training cohort containing 177 PC patients. Another five independent datasets were used as the testing cohort to determine the predictive efficiency for further validation. In total, 441 DEGs were selected after considering the enrichment of classical pathways, such as EMT, cell cycle, cell adhesion, and PI3K-AKT. A five-gene signature for risk discrimination was established with high efficacy using LASSO Cox regression in the training group. External validation showed that patients identified by the gene expression signature to be in the high-risk group had poorer prognosis compared with the low-risk patients. Further investigation identified the differential epigenetic modification patterns of the five genes, which indicated their roles in tumor progression and their effect on therapy. In conclusion, we constructed a robust five-gene expression signature that could predict the OS of PC patients, offering a new insight for risk discrimination in daily clinical practice.

Surgical resection of metastatic pancreatic cancer: is it worth it?-a 15-year experience at a single Chinese center.

BACKGROUND: The significance of surgical resection in the treatment of metastatic pancreatic ductal adenocarcinoma (PDAC) is currently unclear. This study aimed to summarize and clarify the experience of surgical treatment of M1 PDAC in our center and evaluate whether it may offer benefits to some metastatic PDAC patients. METHODS: We analyzed the data of the patients with M1 PDAC who underwent synchronous tumor resection between 2003 and 2014 at Ruijin Hospital. Simultaneously, clinical data for M1 PDAC patients who underwent palliative bypass or exploratory laparotomy only was also collected during the same period as control. Every patient was followed up at least 3 years after hospitalization. The follow-up endpoint was December 31, 2017. RESULTS: A total of 36 patients underwent synchronous tumor resection; of them, 7 received postoperative adjuvant chemotherapy. Their 1-, 2-, and 3-year survival rates were 27.3%, 21.2%, and 7.1%, respectively, and the overall survival was 7.9 months. The overall survival of the palliative bypass and exploratory laparotomy groups was only 4 and 3.7 months, respectively (P<0.05). CONCLUSIONS: It is unclear whether synchronous tumor resection can benefit M1 PDAC patients due to tumor heterogeneity and differences in tumor burden. However, our current experience indicated that synchronous tumor resection can be safely performed and might be appropriate for some highly selected patients due to the relatively longer survival time. Combined (neo)adjuvant chemotherapy would further prolong overall survival in these patients.

Tumor copy number instability is a significant predictor for late recurrence after radical surgery of pancreatic ductal adenocarcinoma.

OBJECTIVE: Our study examined the association between molecular features and clinical results of pancreatic ductal adenocarcinoma (PDAC) patients, aiming to explore the genomic determinants of the recurrence and prognosis of PDAC after surgical removal. METHODS: This retrospective study analyzed 181 PDAC patients who received pancreatectomy and adjuvant chemotherapy, with 67 patients in the training set. An internal validation set of 48 patients and an external validation set of 66 patients were used to validate the result. Comprehensive genomic profiling was performed on formalin-fixed paraffin-embedded (FFPE) tumor specimens to determine genomic features using the designed cancer-related gene panel based on next-generation sequencing (NGS). RESULTS: Significant differences were identified between the late recurrence (LR) group and early recurrence (ER) group in tumor copy number instability (CNI) levels. Next, the utility of low CNI (the middle and lowest tertile) with regard to predicting LR was confirmed in the training, internal, and external validation sets. Further univariate and multivariate analyses revealed that CNI was an independent predictive and prognostic biomarker, and had higher predictive accuracy for LR than CA19-9 level, pathological stage, tumor size, and age. In addition, CNI combined with lymph node (LN) metastasis status could provide a more accurate model for predicting LR of PDAC. CONCLUSION: We discovered and validated the association between CNI and clinical outcome in 181 patients with resectable PDAC, demonstrating the utility of lower tumor CNI levels as biomarkers of postoperative LR and favorable prognosis. Moreover, the combination of CNI and LN metastasis status elevated the predictive accuracy and illuminated strategies for patient stratification.

TFEB-mediated lysosomal biogenesis and lysosomal drug sequestration confer resistance to MEK inhibition in pancreatic cancer.

Oncogenic KRAS mutations are encountered in more than 90% of pancreatic ductal adenocarcinomas. MEK inhibition has failed to procure any clinical benefits in mutant RAS-driven cancers including pancreatic ductal adenocarcinoma (PDAC). To identify potential resistance mechanisms underlying MEK inhibitor (MEKi) resistance in PDAC, we investigated lysosomal drug accumulation in PDAC models both in vitro and in vivo. Mouse PDAC models and human PDAC cell lines as well as human PDAC xenografts treated with the MEK inhibitor trametinib or refametinib led to an enhanced expression of lysosomal markers and enrichment of lysosomal gene sets. A time-dependent, increase in lysosomal content was observed upon MEK inhibition. Strikingly, there was a strong activation of lysosomal biogenesis in cell lines of the classical compared to the basal-like molecular subtype. Increase in lysosomal content was associated with nuclear translocation of the Transcription Factor EB (TFEB) and upregulation of TFEB target genes. siRNA-mediated depletion of TFEB led to a decreased lysosomal biogenesis upon MEK inhibition and potentiated sensitivity. Using LC-MS, we show accumulation of MEKi in the lysosomes of treated cells. Therefore, MEK inhibition triggers lysosomal biogenesis and subsequent drug sequestration. Combined targeting of MEK and lysosomal function may improve sensitivity to MEK inhibition in PDAC.

MEK Inhibition Targets Cancer Stem Cells and Impedes Migration of Pancreatic Cancer Cells In Vitro and In Vivo.

Pancreatic ductal adenocarcinoma (PDAC) remains a devastating disease with a very poor prognosis. At the same time, its incidence is on the rise, and PDAC is expected to become the second leading cause of cancer-related death by 2030. Despite extensive work on new therapeutic approaches, the median overall survival is only 6-12 months after diagnosis and the 5-year survival is less than 7%. While pancreatic cancer is particularly difficult to treat, patients usually succumb not to the growth of the primary tumor, but to extensive metastasis; therefore, strategies to reduce the migratory and metastatic capacity of pancreatic cancer cells merit close attention. The vast majority of pancreatic cancers harbor RAS mutations. The outstanding relevance of the RAS/MEK/ERK pathway in pancreatic cancer biology has been extensively shown previously. Due to their high dependency on Ras mutations, pancreatic cancers might be particularly sensitive to inhibitors acting downstream of Ras. Herein, we use a genetically engineered mouse model of pancreatic cancer and primary pancreatic cancer cells were derived from this model to demonstrate that small-molecule MEK inhibitors functionally abrogate cancer stem cell populations as demonstrated by reduced sphere and organoid formation capacity. Furthermore, we demonstrate that MEK inhibition suppresses TGFß-induced epithelial-to-mesenchymal transition and migration in vitro and ultimately results in a highly significant reduction in circulating tumor cells in mice.

MiR-17-5p enhances pancreatic cancer proliferation by altering cell cycle profiles via disruption of RBL2/E2F4-repressing complexes.

The members of the miR-17-92 cluster are upregulated in various cancers and function as a cluster of oncogenic miRNA. Our study characterized a new function of miR-17-5p, a member of the miR-17-92 cluster, in regulating cell proliferation in pancreatic cancer. Our results indicate that miR-17-5p was up-regulated in pancreatic adenocarcinoma and directly targeted the retinoblastoma-like protein 2 (RBL2), a tumor suppressor belonging to the Rb family. High levels of miR-17-5p and low levels of RBL2 were associated with poor prognosis. RBL2 interacted with the transcription factor E2F4 and bound to the promoter regions of the E2F target genes. Disruption of the RBL2/E2F4 complex by miR-17-5p overexpression shifted the activity of E2F from gene repressing to gene activating, which induced cell cycle entry and proliferation. These results suggest that miR-17-5p promoted proliferation in pancreatic ductal adenocarcinoma cells (PDAC), and altered cell cycle profiles in vivo and in vitro, by disrupting the RBL2/E2F4-associated gene repressing complexes via direct targeting of RBL2. The new regulatory network, involving miR-17-5p and RBL2, emerges as a new target of PDAC treatment.