Pancreatic Cancer Invasion Research Articles

Role of Neuropeptide Y in neural invasion in pancreatic cancer

Role of Neuropeptide Y in neural invasion in pancreatic cancer

MDSCs and NK cells mediate a novel promoting role for neural invasion in pancreatic cancer

MDSCs and NK cells mediate a novel promoting role for neural invasion in pancreatic cancer

Venous resections and reconstructions in surgery of pancreatic cancer

Aim. To evaluate results of venous resections in tumor infiltration of venous wall in pancreatic cancer (PC).
 Materials and Methods. The study included 74 patients with PC and tumor invasion of the wall of the mesenteric-portal system (T3 N0-1 M0). The control group included patients (n=53), receiving palliative chemotherapy. The average age of patients in the group of surgical treatment was 61.89.8 years, in the control group 63.210.1 years (р0.05), the average diameter of the tumor was 39 mm and 43 mm, respectively (р0.05). In 62 cases of the group of surgical treatment the tumor was located in the head of pancreas (P), the patients were conducted pancreaticoduodenal resection with venous resection. In the rest of cases (n=12) the tumor was located in the body of P, corporocaudal resection of P was conducted with venous resection.
 Results. In the early postoperative period 2.7% of patients developed thrombosis of the reconstruction zone, 1.4% developed bleeding. 30-Day postoperative lethality was 4.1%. Median survival in surgical treatment of PC with venous resection was higher in comparison with palliative chemotherapy: 19 months vs 13 months, р0.05. In the group of venous resection the lowest annual survival (46.2%) was noted in patients with marginal resection of the vein. No significant differences were found in the parameters of survival with use of direct venous anastomose and venous prosthetics (66.7% vs 63.2%, p0.05).
 Conclusions. Angioplastic interventions permitting to achieve microscopically complete resection of the tumor in PC with tumor infiltration of mesenteric-portal system, permit to improve survival of patients in comparison with palliative chemotherapy.

TRIM37 Mediates Chemoresistance and Maintenance of Stemness in Pancreatic Cancer Cells via Ubiquitination of PTEN and Activation of the AKT-GSK-3β-β-Catenin Signaling Pathway.

PurposeThe tripartite motif-containing family member TRIM37 is involved in a number of important biological and pathological processes, and it has recently been shown to be an essential regulator of protein ubiquitination and a contributor to tumorigenesis. We previously showed that TRIM37 is overexpressed in and promotes the proliferation and invasion of pancreatic cancer (PC).MethodsSphere formation, flow cytometric, qRT-PCR, western blot, colony formation, EdU incorporation, mouse xenograft model, TUNEL and IHC assays were performed to detect the role of TRIM37 in stemness and chemoresistance of PC in vitro and in vivo. Bioinformatics analysis and dual-luciferase reporter assays were used to determine which intracellular pathways might mediate the effects of TRIM37 in PC cells. Immunofluorescent(IF) staining, co-immunoprecipitation(CO-IP), protein stability and ubiquitination assays were performed to investigate the relationship between TRIM37 and PTEN.ResultsTRIM37 modulates the ubiquitination and degradation of the tumor suppressor phosphatase and tensin homolog (PTEN), which negatively regulates the AKT–GSK-3β–β-catenin signaling pathway, thereby sustaining aberrant activation of PC cells. High expression of TRIM37 combined with low expression of PTEN correlates with poor survival of PC patients.ConclusionsCollectively, our results suggest that inhibition of the TRIM37–AKT–GSK-3β–β-catenin axis may be a promising strategy for treatment of PC.

MicroRNA-221-3p is related to survival and promotes tumour progression in pancreatic cancer: a comprehensive study on functions and clinicopathological value

BackgroundThe microRNA miR-221-3p has previously been found to be an underlying biomarker of pancreatic cancer. However, the mechanisms of miR-221-3p underlying its role in pancreatic cancer pathogenesis, proliferation capability, invasion ability, drug resistance and apoptosis and the clinicopathological value of miR-221-3p have not been thoroughly studied.MethodsBased on microarray and miRNA-sequencing data extracted from Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), relevant literature, and real-time quantitative PCR (RT-qPCR), we explored clinicopathological features and the expression of miR-221-3p to determine its clinical effect in pancreatic cancer. Proliferation, migration, invasion, apoptosis and in vitro cytotoxicity tests were selected to examine the roles of mir-221-3p. In addition, several miR-221-3p functional analyses were conducted, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Protein–protein interaction (PPI) network analyses, to examine gene interactions with miR-221-3p.ResultsThe findings of integrated multi-analysis revealed higher miR-221-3p expression in pancreatic cancer tissues and blood than that in para-carcinoma samples (SMD of miR-221-3p: 1.52; 95% CI 0.96, 2.08). MiR-221-3p is related to survival both in pancreatic cancer and pancreatic ductal adenocarcinoma patients. Cell experiments demonstrated that miR-221-3p promotes pancreatic cancer cell proliferation capability, migration ability, invasion ability, and drug resistance but inhibits apoptosis. Further pancreatic cancer bioinformatics analyses projected 30 genes as the underlying targets of miR-221-3p. The genes were significantly distributed in diverse critical pathways, including microRNAs in cancer, viral carcinogenesis, and the PI3K-Akt signalling pathway. Additionally, PPI indicated four hub genes with threshold values of 5: KIT, CDKN1B, RUNX2, and BCL2L11. Moreover, cell studies showed that miR-221-3p can inhibit these four hub genes expression in pancreatic cancer.ConclusionsOur research revealed that pancreatic cancer expresses a high-level of miR-221-3p, indicating a potential miR-221-3p role as a prognosis predictor in pancreatic cancer. Moreover, miR-221-3p promotes proliferation capacity, migration ability, invasion ability, and drug resistance but inhibits apoptosis in pancreatic cancer. The function of miR-221-3p in the development of pancreatic cancer may be mediated by the inhibition of hub genes expression. All these results might provide an opportunity to extend the understanding of pancreatic cancer pathogenesis.

Colonic varices: a rare complication of pancreatic cancer

A 55-year-old man was diagnosed with pancreatic cancer of the uncus and received chemotherapy (modified FOLFIRINOX). Ten months later, he was admitted to our hospital with massive lower gastrointestinal bleeding. Contrast-enhanced CT showed ascending colon varices caused by the occlusion of the superior mesenteric vein (SMV) due to pancreatic cancer invasion. Colonoscopy revealed tortuous varices with red spots in the ascending colon. The patient received blood transfusions and was discharged; however, he was hospitalized for recurrent massive lower gastrointestinal bleeding 3 months later. During this readmission, we performed the transileocolic vein obliteration method due to SMV stenosis and the absence of an obvious shunt. He experienced an uneventful post-operative recovery, and contrast-enhanced CT after 2months revealed no recurrence of colonic varices. Ectopic varices are portosystemic venous collaterals resulting from portal hypertension occurring in any locations other than the esophagogastric region. Colonic varices have rarely been reported before. Patients with pancreatic cancer may present with gastrointestinal bleeding caused by tumor bleeding or esophagogastric varices; however, ectopic varices such as colon varices, a rare complication of pancreatic cancer, should be considered in patients with obscure gastrointestinal bleeding.

MicroRNA-23b-3p promotes pancreatic cancer cell tumorigenesis and metastasis via the JAK/PI3K and Akt/NF-κB signaling pathways.

MicroRNA (miR)-23b-3p plays an important role in tumor growth, proliferation, invasion and migration in pancreatic cancer (PC). However, the function and mechanistic role of miR-23b-3p in the development of PC remains largely unknown. In the present study, the miR-23b-3p levels in the serum of patients with PC were found to be elevated, and the phosphorylation levels of Janus kinase (JAK)2, PI3K, Akt and NF-κВ were found to be upregulated. In addition, miR-23b-3p was induced in response to interleukin-6 (IL-6), which is known to be involved in the progression of PC. Overexpression of miR-23b-3p, on the other hand, activated the JAK/PI3K and Akt/NF-κB signaling pathways in PC cells, as evidenced by miR-23b-3p-induced upregulation of phosphorylated (p-)JAK2, p-PI3K, p-Akt and p-NF-κВ, as well as the downregulation of PTEN; and these effects were found to be reversible by miR-23b-3p inhibition. Furthermore, miR-23b-3p was found to downregulate PTEN by directly targeting the 3′-untranslated region of PTEN mRNA. Notably, in an in vivo xenograft mouse model, overexpression of miR-23b-3p accelerated PC cell-derived tumor growth, activated the JAK/Akt/NF-κВ signaling pathway and promoted liver metastasis. In contrast, knockdown of miR-23b-3p suppressed tumor growth and metastasis as well as JAK/Akt/NF-κВ signaling activity. In vivo imaging of the mice further confirmed the metastasis promoting role of miR-23b-3p in PC. These results suggested that miR-23b-3p enhances PC cell tumorigenesis and metastasis, at least, partially via the JAK/PI3K and Akt/NF-κB signaling pathways. Therefore, targeting miR-23b-3p or the JAK/PI3K and Akt/NF-κB signalings may be potential therapeutic strategy against PC.

Schwann Cell Stimulation of Pancreatic Cancer Cells: A Proteomic Analysis.

Schwann cells (SCs), the glial component of peripheral nerves, have been identified as promoters of pancreatic cancer (PC) progression, but the molecular mechanisms are unclear. In the present study, we aimed to identify proteins released by SCs that could stimulate PC growth and invasion. Proteomic analysis of human primary SC secretome was performed using liquid chromatography–tandem mass spectrometry, and a total of 13,796 unique peptides corresponding to 1,470 individual proteins were identified. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment were conducted using the Database for Annotation, Visualization, and Integrated Discovery. Metabolic and cell–cell adhesion pathways showed the highest levels of enrichment, a finding in line with the supportive role of SCs in peripheral nerves. We identified seven SC-secreted proteins that were validated by western blot. The involvement of these SC-secreted proteins was further demonstrated by using blocking antibodies. PC cell proliferation and invasion induced by SC-conditioned media were decreased using blocking antibodies against the matrix metalloproteinase-2, cathepsin D, plasminogen activator inhibitor-1, and galectin-1. Blocking antibodies against the proteoglycan biglycan, galectin-3 binding protein, and tissue inhibitor of metalloproteinases-2 decreased only the proliferation but not the invasion of PC cells. Together, this study delineates the secretome of human SCs and identifies proteins that can stimulate PC cell growth and invasion and therefore constitute potential therapeutic targets.

Abstract 4711: Novel mechanism involved in the regulation ofoncogenic Axl receptor tyrosine kinase in cancer

Abstract Background: Oncogenic receptor tyrosine kinase Axl is overexpressed and plays an important role in multiple human cancers. However the mechanisms of Axl overexpression in cancer remain unclear. This study is to investigate the mechanisms that regulate Axl expression in pancreatic cancer. Experimental procedures: The interactions between HPK1, Axl and c-Cbl were examined using co-immunoprecipitation and immunoblotting. Inhibitors of endocytic pathway and immunofluorescence were used to examine the underlying mechanisms of HPK1-mediated Axl degradation. The functional significance of HPK1-mediated Axl degradation in the invasive capability of pancreatic ductal adenocarcinoma (PDAC) cells and it downstream signaling pathways were examined using HPK1 stable PDAC cells. Immunohistochemistry was used to examine the in vivo correlation between HPK1 and Axl in human pancreatic intraepithelial neoplasia. The RNA sequencing data of HPK1 and Axl expression and survival data of 176 pancreatic cancer patients in the Cancer Genome Atlas (TCGA) database were downloaded from the Human Protein Atlas (https://www.proteinatlas.org). The expression of HPK1 and Axl was categorized as low or high using the cutoff values set by TCGA (3.42 for HPK1 and 14.09 for Axl). Survival analysis were performed using the Kaplan-Meier method and the log-rank test was used to evaluate the statistical significance of differences. Results: We identified Axl as a novel HPK1-interacting protein and demonstrated for the first time that HPK1 down-regulated Axl and decreased the half-life of Axl protein. HPK1-mediated Axl degradation was inhibited by leupeptin, baflomycin A1 and monensin which inhibit endocytic pathway. HPK1 accelerates the movement of Axl from the plasma membrane onto endosomes in pancreatic cancer cells after treated with Gas6. HPK1 increased the binding of Axl to c-Cbl, promoted Axl ubiquitination, decreased Axl signaling including phospho-Akt and phospho-Erk, and decreased the invasion capability of pancreatic cancer. More importantly, we showed that Axl expression inversely correlated with HPK1 expression in human pancreatic intraepithelial neoplasia (P=0.005). Low expression of HPK1 and high expression of Axl correlated significantly with poor survival in patients with PDAC (P<0.001). Conclusions: Our results suggest a novel tumor suppressor mechanism of HPK1 in which it targets Axl for degradation via the endocytic pathway. Loss of HPK1 may contribute to Axl overexpression and enhance its downstream signaling and tumor invasion in pancreatic cancer. Citation Format: Hua Wang, Xianzhou Song, Hironari Akasaka, Reza Abbasgholizadeh, Ji-Hyun Shin, Craig D. Logsdon, Anirban Maitra, Andrew J. Bean, Huamin Wang. Novel mechanism involved in the regulation ofoncogenic Axl receptor tyrosine kinase in cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4711.

Abstract 368: Defining the invasive gene signature using patient derived pancreatic cancer organoids

Abstract Pancreatic cancer mortality is rising due to late detection and established metastasis. Despite the recent advances in cancer research, metastasis research has been hampered by the lack of models that recapitulate this complex process. Traditional cell culture and animal models provided insights on cancer cell migration and dissemination. But local invasion, which precedes all the events in the metastatic cascade, remains poorly understood. Patient-derived organoids (PDO) present an innovative platform in which the earliest step of metastasis can be observed and manipulated ex vivo. We developed a pancreatic cancer organoid model using surgically resected tumors from The Johns Hopkins Hospital. We previously reported that there are two invasive patterns in pancreatic cancer PDOs - Mesenchymal and Collective invasion, with one dominating pattern in every PDO culture. Here, we describe the gene expression signature associated with local invasion in pancreatic cancer by comparing the whole transcriptome of matched invasive and non-invasive organoids from the same tumor. For this study, PDOs were cultured for 7 days ex vivo and we manually collected 50 invasive and non-invasive organoids from each culture for RNA-seq analysis. To date, the invasive and non-invasive organoids from 6 PDO lines have been analyzed. The list of differentially expressed genes between invasive and non-invasive organoids includes 1,106 genes with FDR 0.001, with DACT1, DKK3 and KIF26B being most differentially expressed. Pathway analysis identifies that the invasive phenotype is associated with extracellular matrix receptor interaction, focal adhesion and PI3K-Akt signaling pathways. In conclusion, our findings revealed a distinct gene expression signature between invasive and non-invasive cells in PDOs. Interestingly, we did not find significant up or down-regulation in the classical EMT markers in our results, which suggests possible pancreatic cancer-specific metastasis programs exist. We believe our results can inform new diagnostic and prognostic tools and help identify anti-metastasis targets in pancreatic cancer. Citation Format: Yea Ji Jeong, Michael G. Lerner, Yuchen Ge, Hildur Knutsdottir, Bernat Navarro-Serer, Peter E. Chianchiano, Andrew J. Ewald, Joel S. Bader, Laura D. Wood. Defining the invasive gene signature using patient derived pancreatic cancer organoids [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 368.

Methyl-CpG-binding protein 2 drives the Furin/TGF-\u03b21/Smad axis to promote epithelial\u2013mesenchymal transition in pancreatic cancer cells

Methyl-CpG-binding protein 2 (MeCP2) has been characterized as an oncogene in several types of cancer. However, its precise role in pancreatic ductal adenocarcinoma (PDAC) remains unclear. Hence, this study aimed to evaluate the potential role of MeCP2 in pancreatic cancer progression. We found that MeCP2 was upregulated in pancreatic cancer tissues, enhanced migration, invasion, and proliferation in pancreatic cancer cells, and promoted tumorigenesis. Further evidence revealed that MeCP2 remarkably increased the mesenchymal markers vimentin, N-cadherin, and Snail, and downregulated the expression of the epithelial markers E-cadherin and ZO-1, indicating that MeCP2 promotes epithelial–mesenchymal transition (EMT). In addition, we found that MeCP2 upregulated the expression of Furin, activated TGF-β1, and increased the levels of p-Smad2/3. Importantly, we demonstrated that MeCP2, as a coactivator, enhanced Smad3 binding to the furin promoter to improve its transcription. Therefore, MeCP2/Smads drive the expression of Furin to activate TGF-β1, and in turn, phosphorylate Smad2/3, which forms a positive-feedback axis to promote EMT in pancreatic cancer cells.

Salidroside inhibits proliferation, migration and invasion of human pancreatic cancer PANC1 and SW1990 cells through the AKT and ERK signaling pathway.

Salidroside is the main compounds extracted from the Chinese medicine Rhodiola rosea and has many pharmacological effects, including anti-tumor effects. However, the role of salidroside in human pancreatic cancer remains poorly known. Thus, the focus of this study was to evaluate the inhibitory effect of purified salidroside on human pancreatic cancer cells and its underlying molecular mechanisms. PANC1 and SW1990 cells were incubated with various concentrations of salidroside, and CCK-8 assay, colony formation, apoptosis, migration and invasion, western blot were conducted. As a result, it was found that salidroside significantly inhibited pancreatic cancer cells viability, proliferation, migration and invasion, and also induced cell apoptosis. Furthermore, we also detected that salidroside inhibited pancreatic cancer cells by downregulating the AKT and ERK signaling pathways. In conclusion, these findings suggest that salidroside may be a promising candidate for the development of a therapy of human pancreatic cancer.

NAF-1 Inhibition by Resveratrol Suppresses Cancer Stem Cell-Like Properties and the Invasion of Pancreatic Cancer.

Resveratrol is a natural polyphenolic compound with multiple biological effects, e.g., proliferation inhibition, anti-oxidation, and neuroprotection. Besides that, studies have shown that resveratrol inhibits tumor growth and migration, as well as epithelial–mesenchymal transition (EMT). However, its molecular mechanisms in tumor progression are not fully understood. Nutrient-deprivation autophagy factor-1 (NAF-1) is mainly found in the endoplasmic reticulum and mitochondrial outer membrane. It is an important genetic locus for regulating oxidative stress and autophagy. The molecular mechanism of NAF-1 in pancreatic cancer is currently unclear. The current study found that NAF-1 is expressed in pancreatic cancer tissue and correlated with the progression of pancreatic cancer. Furthermore, we found that NAF-1 inhibition significantly inhibits the stem cell characteristics and the invasion and migration abilities of pancreatic cancer cells. In a subcutaneous xenograft model of pancreatic cancer in nude mice, resveratrol inhibited the expression of NAF-1, thereby inhibiting tumor growth. Taken together, resveratrol could be an effective anti-tumor drug, and NAF-1 may be a rational therapeutic target.

Honokiol Suppressed Pancreatic Cancer Progression via miR-101/Mcl-1 Axis.

BackgroundPancreatic cancer is one of the most aggressive malignancies. The present study aimed to examine the anti-tumor effects of honokiol in pancreatic cancer and to explore the underlying molecular mechanisms.Materials and MethodsIn vitro functional assays determined pancreatic cancer cell proliferation, apoptosis and invasion. Xenograft nude mice model determined the in vivo anti-cancer effects of honokiol. Luciferase reporter assay determined the interaction between miR101 and myeloid cell leukemia-1 (Mcl-1).ResultsHonokiol concentration-dependently suppressed pancreatic cancer cell viability. In addition, honokiol increased the caspase-3 activity and cell apoptotic rates, induced cell cycle arrest at G0/G1 phase, and inhibited cell invasion in pancreatic cancer. Interestingly, honokiol treatment induced up-regulation of miR-101 in pancreatic cancer cells. Knockdown of miR-101 attenuated the honokiol-induced cell apoptosis and inhibition in cell invasion of pancreatic cancer cells. On the other hand, miR-101 overexpression induced cell apoptosis and inhibited cell viability and invasion in pancreatic cancer. Further mechanistic study verified that Mcl-1 was negatively regulated by miR-101, and Mcl-1 overexpression counteracted the tumor-suppressive effects of honokiol on the pancreatic cancer cells. In vivo studies showed that honokiol dose-dependently suppressed tumor growth of pancreatic cancer in the nude mice and up-regulated miR-101 expression but down-regulated Mcl-1 expression in tumor tissues.ConclusionOur data showed that honokiol suppressed pancreatic cancer progression via miR-101-Mcl-1 axis. Honokiol could be a promising candidate for cancer prevention and/or therapeutic treatment for pancreatic cancer.

Expression of miRNA let-7a and HMGA2 and Diagnostic Value of Serum miRNA let-7a Level in Pancreatic Cancer

To investigate the diagnostic value of miRNA let-7a, high mobility group A2 (HMGA2) expression and serum miRNA let-7a level in pancreatic cancer. From January 2014 to January 2019, 60 patients with pancreatic cancer were collected for fresh pancreatic ductal adenocarcinoma tissue and normal pancreatic tissue adjacent to the cancer after the operation. Serum samples before and after operation were also collected, while 60 healthy people were enrolled as the control group. The expression of miRNA let-7a (qRT-PCR) and HMGA2 (qRT-PCR and Western blot) in cancer and adjacent normal tissues were measured. The serum level of miRNA let-7a was detected by qRT-PCR. The relationship between miRNA let-7a and HMGA2 expression and the clinicopathological features of pancreatic cancer was analyzed. The diagnostic value of serum miRNA let-7a pre-operation in patients with pancreatic cancer was also analyzed with ROC curve. Compared with normal tissues adjacent to the cancer, the expression level of miRNA let-7a in pancreatic cancer tissues decreased ( t=20.291, P<0.01), and the expression of HMGA2 mRNA increased ( t=46.681, P<0.01). The expression of HMGA2 protein in cancer tissues was higher than that in normal tissues adjacent to the cancer ( t=22.973, P<0.01). The serum level of miRNA let-7a in pancreatic cancer patients was significantly lower than that in healthy controls ( t=24.854, P<0.01). The relative level of serum miRNA let-7a at 1 week after surgery was significantly lower than that before surgery in pancreatic cancer patients ( t=6.885, P<0.01). There was a positive correlation between cancer tissue and serum miRNA let-7a expression 1 week after surgery ( r=0.411, P=0.000). The relative expression levels of miRNA let-7a and HMGA2 in pancreatic cancer tissues were significantly different in different TNM stages and lymph node metastasis ( P<0.05). The area under curve of pre-operation serum miRNA let-7a for the diagnosis of pancreatic cancer was 0.823 ( 95% confidence interval: 0.665-0.917); when the optimal cut-off value of miRNA let-7a was 0.614, the sensitivity was 82.3%, the specificity was 74.1%. The expression of HMGA2 may be involved in the invasion and metastasis of pancreatic cancer. The level of serum miRNA let-7a may provide a reference for the diagnosis and postoperative monitoring of pancreatic cancer.

The Interaction Between Long Non-coding RNA HULC and MicroRNA-622 via Transfer by Extracellular Vesicles Regulates Cell Invasion and Migration in Human Pancreatic Cancer.

Although non-coding RNAs (ncRNAs) are involved in disease pathogenesis, their contributions to pancreatic ductal adenocarcinoma (PDAC) remain unclear. Recently, the interrelationship between two classes of ncRNA, long non-coding RNAs (lncRNAs), and microRNAs (miRNAs), has been reported to contribute to the epigenetic regulation of gene expression in several diseases including cancers. Moreover, some ncRNAs can be transferred by extracellular vesicles (EVs) from their donor cells to recipient cells. We previously verified that lncRNA HULC is up-regulated in PDAC cells and the intercellular transfer of HULC by EVs can promote PDAC cell invasion and migration through the induction of epithelial–mesenchymal transition (EMT). Therefore, we identified the miRNA that could target HULC and investigated the functional contributions of the miRNA–HULC interaction and EV transfer of miRNA to the EMT pathway in PDAC. Microarray analysis revealed 187 miRNAs that were decreased to <0.87-fold in Panc-1 cells treated with TGF-β compared with the control. Of these, miR-622 was predicted to target HULC directly by bioinformatics analysis. Expression of miR-622 was significantly down-regulated by TGF-β in a panel of PDAC cells. miR-622 overexpression by a miRNA mimic significantly decreased HULC expression, increased E-cadherin expression, and decreased expression of Snail, N-cadherin, and vimentin. Moreover, overexpression of miR-622 significantly reduced cell invasion and migration whereas inhibition of miR-622 increased HULC expression and promoted EMT signaling, invasion, and migration of PDAC cells. Furthermore, incubation with miR-622-overexpressing EVs could transfer miR-622, which significantly elevated miR-622 expression and decreased cell invasion and migration via inhibition of the EMT pathway in recipient PDAC cells. These results provide mechanistic insights into the development of PDAC by demonstrating that miR-622, as a miRNA downregulated by TGF-β, could target HULC and suppress invasion and migration by inhibiting EMT signaling via EV transfer. These observations may identify EV-encapsulated miRNA as a novel therapeutic target for human PDAC.

Chemokines: the (un)usual suspects in pancreatic cancer neural invasion

Pancreatic cancer is notorious for its affinity for invading nerves. A new study using a systematic unbiased RNA-interference screen of neuronal chemokines in cocultures of mouse sensory neurons and pancreatic cancer cells has now identified CCL21 and CXCL10 as key mediators of neural invasion, neural remodelling and pain in pancreatic cancer.

MiR‑142‑5p inhibits pancreatic cancer cell migration and invasion by targeting PIK3CA

Pancreatic cancer is a fatal disease with a high mortality rate and poor prognosis worldwide. The aberrant expression of microRNAs (miRs) is associated with cancer development and progression. The present study aimed to evaluate the functional role of miR‑142‑5p in migration and invasion, and investigated its underlying molecular mechanism in pancreatic cancer cells. First, it was identified that miR‑142‑5p expression was downregulated in pancreatic cancer tissues and cell lines by reverse transcription‑quantitative polymerase chain reaction. Furthermore, phosphoinositide‑3‑kinase catalytic subunitα (PIK3CA) was identified as a target of miR‑142‑5p. The expression of PIK3CA was upregulated in tumor tissues and its expression was negatively regulated by miR‑142‑5p expression. Notably, overexpression of miR‑142‑5p inhibited the proliferation, migration and invasion of PanC1 cells, while PIK3CA reversed this inhibition. In addition, miR‑142‑5p suppressed the expression of focal adhesion kinase (FAK) and matrix metalloproteinase (MMP)9, as well as phosphorylated protein kinase B (AKT) protein level, while PIK3CA reversed the suppression induced by miR‑142‑5p. In conclusion, miR‑142‑5p functions as a tumor suppressor, which inhibits the migration and invasion of pancreatic cancer by suppressing the expression of FAK and MMP9, as well as the phosphatidylinositol 3‑kinase/AKT signaling pathway by targeting PIK3CA. These findings suggest that miR‑142‑5p may be a novel therapeutic target for the treatment of pancreatic cancer.

Chemopreventive effect of Betulinic acid via mTOR -Caspases/Bcl2/Bax apoptotic signaling in pancreatic cancer

BackgroundPancreatic cancer is aggressive with no symptoms until the advanced stage reached. The increased resistance of pancreatic cancer to chemotherapy demonstrates a dilemma in the clinical field. Hence, it is a matter of great urgency to develop an effective drug to treat patients with pancreatic cancer. Betulinic acid is a major triterpene isolated from spina date seed. Several studies have suggested its low toxicity and side effects to patients with malaria and inflammation. However, relevant studies on betulinic acid in inhibiting cancer were insufficient and the molecular mechanism was unclear. This study aimed to systematically explore the potential anti-cancer functions of betulinic acid in pancreatic cancer, and investigate its underlying molecular mechanism.MethodsThe Counting Kit-8 assay, colony formation, transwell invasion assay, wound healing assay, flow cytometry and xenograft nude mice model were used to evaluate the effect of betulinic acid on the proliferation, invasion and migration ability of pancreatic cancer cells.ResultsOur results showed that betulinic acid obviously suppressed pancreatic cancer both in vitro and in vivo in a dose-dependent manner. We also determined that betulinic acid inhibited pancreatic cancer by specifically targeting mTOR signaling rather than Nrf2 or JAK2.ConclusionsThese findings clarify that betulinic acid is a potential and valuable anticancer agent for pancreatic cancer, and indicate the specific molecular target of betulinic acid.

The Membrane Protein Sortilin Can Be Targeted to Inhibit Pancreatic Cancer Cell Invasion

Pancreatic cancer has a dismal prognosis, and there is no targeted therapy against this malignancy. The neuronal membrane protein sortilin is emerging as a regulator of cancer cell development, but its expression and impact in pancreatic cancer are unknown. This study found that sortilin expression was higher in pancreatic cell lines versus normal pancreatic ductal epithelial cells, as shown by Western blot analysis and mass spectrometry. The increased sortilin level in pancreatic cancer cells was confirmed by immunohistochemistry in a series of 99 human pancreatic adenocarcinomas versus 48 normal pancreatic tissues (P=0.0014). Sortilin inhibition by siRNA and the pharmacologic inhibitor AF38469 strongly reduced the adhesion and invasion of pancreatic cancer cells without affecting cell survival and viability. Sortilin inhibition also decreased the phosphorylation of the focal adhesion kinase in Tyr925. Together, these data show that sortilin contributes to pancreatic cancer invasion and could eventually be targeted in therapy.