Objective: To explore the mechanism of Doublecortin-like kinase 1 (DCLK1) in promoting cell migration, invasion and proliferation in pancreatic cancer. Methods: The correlation between DCLK1 and Hippo pathway was analyzed using TCGA and GTEx databases and confirmed by fluorescence staining of pancreatic cancer tissue microarrays. At the cellular level, immunofluorescence staining of cell crawls and western blot assays were performed to clarify whether DCLK1 regulates yes associated protein1 (YAP1), a downstream effector of the Hippo pathway. Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) was used to analyze the expressions of YAP1 binding transcription factor TEA-DNA binding proteins (TEAD) and downstream malignant behavior-promoting molecules CYR61, EDN1, AREG, and CTGF. Transwell test of the DCLK1-overexpressing cells treated with the Hippo pathway inhibitor Verteporfin was used to examine whether the malignant behavior-promoting ability was blocked. Analysis of changes in the proliferation index of experimental cells used real-time label-free cells. Results: TCGA combined with GTEx data analysis showed that the expressions of DCLK1 and YAP1 molecules in pancreatic cancer tissues were significantly higher than those in adjacent tissues (P<0.05). Moreover, DCLK1was positively correlated with the expressions of many effectors in the Hippo pathway, including LATS1 (r=0.53, P<0.001), LATS2 (r=0.34, P<0.001), MOB1B (r=0.40, P<0.001). In addition, the tissue microarray of pancreatic cancer patients was stained with multicolor fluorescence, indicated that the high expression of DCLK1 in pancreatic cancer patients was accompanied by the up-regulated expression of YAP1. The expression of DCLK1 in pancreatic cancer cell lines was analyzed by the CCLE database. The results showed that the expression of DCLK1 in AsPC-1 and PANC-1 cells was low. Thus, we overexpressed DCLK1 in AsPC-1 and PANC-1 cell lines and found that DCLK1 overexpression in pancreatic cancer cell lines promoted YAP1 expression and accessible to the nucleus. In addition, DCLK1 up-regulated the expression of YAP1 binding transcription factor TEAD and increased the mRNA expression levels of downstream malignant behavior-promoting molecules. Finally, Verteporfin, an inhibitor of the Hippo pathway, could antagonize the cell's malignant behavior-promoting ability mediated by high expression of DCLK1. We found that the number of migrated cells with DCLK1 overexpressing AsPC-1 group was 68.33±7.09, which was significantly higher than 22.00±4.58 of DCLK1 overexpressing cells treated with Verteporfin (P<0.05). Similarly, the migration number of PANC-1 cells overexpressing DCLK1 was 65.66±8.73, which was significantly higher than 37.00±6.00 of the control group and 32.33±9.61 of Hippo pathway inhibitor-treated group (P<0.05). Meanwhile, the number of invasive cells in the DCLK1-overexpressed group was significantly higher than that in the DCLK1 wild-type group cells, while the Verteporfin-treated DCLK1-overexpressed cells showed a significant decrease. In addition, we monitored the cell proliferation index using the real-time cellular analysis (RTCA) assay, and the proliferation index of DCLK1-overexpressed AsPC-1 cells was 0.66±0.04, which was significantly higher than 0.38±0.01 of DCLK1 wild-type AsPC-1 cells (P<0.05) as well as 0.05±0.03 of DCLK1-overexpressed AsPC1 cells treated with Verteporfin (P<0.05). PANC-1 cells showed the same pattern, with a proliferation index of 0.77±0.04 for DCLK1-overexpressed PANC-1 cells, significantly higher than DCLK1-overexpressed PANC1 cells after Verteporfin treatment (0.14±0.05, P<0.05). Conclusion: The expression of DCLK1 is remarkably associated with the Hippo pathway, it promotes the migration, invasion, and proliferation of pancreatic cancer cells by activating the Hippo pathway.
Humans ; Doublecortin-Like Kinases ; Hippo Signaling Pathway ; Verteporfin/pharmacology* ; Cell Line, Tumor ; Protein Serine-Threonine Kinases/metabolism* ; Pancreatic Neoplasms/pathology* ; YAP-Signaling Proteins ; Transcription Factors/metabolism* ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic ; Tumor Suppressor Proteins/genetics*

Humans ; Neuroendocrine Tumors/genetics* ; Prognosis ; X-linked Nuclear Protein/genetics* ; Pancreatic Neoplasms/pathology* ; Telomere/pathology*

The characteristic genetic abnormality of neuroendocrine neoplasms (NENs), a heterogeneous group of tumors found in various organs, remains to be identified. Here, based on the analysis of the splicing variants of an oncogene Focal Adhesion Kinase (FAK) in The Cancer Genome Atlas datasets that contain 9193 patients of 33 cancer subtypes, we found that Box 6/Box 7-containing FAK variants (FAK^6/7) were observed in 7 (87.5%) of 8 pancreatic neuroendocrine carcinomas and 20 (11.76%) of 170 pancreatic ductal adenocarcinomas (PDACs). We tested FAK variants in 157 tumor samples collected from Chinese patients with pancreatic tumors, and found that FAK^6/7 was positive in 34 (75.6%) of 45 pancreatic NENs, 19 (47.5%) of 40 pancreatic solid pseudopapillary neoplasms, and 2 (2.9%) of 69 PDACs. We further tested FAK splicing variants in breast neuroendocrine carcinoma (BrNECs), and found that FAK^6/7 was positive in 14 (93.3%) of 15 BrNECs but 0 in 23 non-NEC breast cancers. We explored the underlying mechanisms and found that a splicing factor serine/arginine repetitive matrix protein 4 (SRRM4) was overexpressed in FAK^6/7-positive pancreatic tumors and breast tumors, which promoted the formation of FAK^6/7 in cells. These results suggested that FAK^6/7 could be a biomarker of NENs and represent a potential therapeutic target for these orphan diseases.
Female ; Humans ; Alternative Splicing ; Breast Neoplasms/metabolism* ; Carcinoma, Pancreatic Ductal/pathology* ; Focal Adhesion Protein-Tyrosine Kinases/therapeutic use* ; Nerve Tissue Proteins/genetics* ; Neuroendocrine Tumors/genetics* ; Oncogenes ; Pancreatic Neoplasms/metabolism*

BACKGROUND: Cell competition is an important feature in pancreatic cancer (PC) progression, but the underlying mechanism remains elusive. This study aims to explore the role of exosomes derived from normal pancreatic ductal epithelial cells involved in PC progression. METHODS: PC cells and pancreatic stellate cells (PSCs) were treated with exosomes isolated from pancreatic ductal epithelial cells. Cell proliferation was assessed by CCK8 assays. Cell migration and invasion were assessed by Transwell assays. PC and matched adjacent non-tumor tissue specimens were obtained from 46 patients pathologically diagnosed with PC at Peking University First Hospital from 2013 to 2017. Tissue miR-485-3p and p21-activated kinase-1 (PAK1) expression was examined by real-time polymerase chain reaction (RT-PCR), and the relationship of the two was analyzed using Pearman's product-moment correlation. The clinical significance of miR-485-3p was analyzed using the Chi-square test, Wilcoxon rank-sum test, and Fisher exact probability, respectively. The binding of miR-485-3p to PAK1 5'-untranslated region (5'-UTR) was examined by luciferase assay. PC cells were xenografted into nude mice as a PC metastasis model. RESULTS: Exosomes from pancreatic ductal epithelial cells suppressed PC cell migration and invasion as well as the secretion and migration of PSCs. MiR-485-3p was enriched in the exosomes of pancreatic ductal epithelial cells but deficient in those of PC cells and PSCs, in accordance with the lower level in PSCs and PC cells than that in pancreatic ductal cells. And the mature miR-485-3p could be delivered into these cells by the exosomes secreted by normal pancreatic duct cells, to inhibit PC cell migration and invasion. Clinical data analysis showed that miR-485-3p was significantly decreased in PC tissues (P < 0.05) and was negatively associated with lymphovascular invasion (P = 0.044). As a direct target of miR-485-3p, PAK1 was found to exert an inhibitory effect on PC cells, and there was a significantly negative correlation between the expression levels of miR-485-3p and PAK1 (r = -0.6525, P < 0.0001) in PC tissues. Moreover, miR-485-3p could suppress PC metastasis in vivo by targeting p21-activated kinase-1. CONCLUSIONS Exosomal miR-485-3p delivered by normal pancreatic ductal epithelial cells into PC cells inhibits PC metastasis by directly targeting PAK1. The restoration of miR-485-3p by exosomes or some other vehicle might be a novel approach for PC treatment.
Animals ; Mice ; MicroRNAs/metabolism* ; Mice, Nude ; p21-Activated Kinases/metabolism* ; Cell Line, Tumor ; Pancreatic Neoplasms/genetics* ; Epithelial Cells/metabolism* ; Pancreatic Ducts/pathology* ; Cell Proliferation ; Cell Movement ; Gene Expression Regulation, Neoplastic

Multiple endocrine neoplasia (MEN) mutation is an autosomal dominant disorder characterized by the occurrence of parathyroid, pancreatic islet, and anterior pituitary tumors. The incidence of insulinoma in MEN is relatively uncommon, and there have been a few cases of MEN manifested with insulinoma as the first symptom in children. We experienced a 9-year-old girl having a familial MEN1 mutation. She complained of dizziness, occasional palpitation, weakness, hunger, sweating, and generalized tonic-clonic seizure that lasted for 5 minutes early in the morning. At first, she was only diagnosed with insulinoma by abdominal magnetic resonance images of a 1.3 × 1.5 cm mass in the pancreas and high insulin levels in blood of the hepatic vein, but after her father was diagnosed with MEN1. We found she had familial MEN1 mutation, and she recovered hyperinsulinemic hypoglycemia after enucleation of the mass. Therefore, the early genetic identification of MEN1 mutation is considerable for children with at least one manifestation.
Alleles ; Base Sequence ; Child ; DNA Mutational Analysis ; Female ; Humans ; Hypoglycemia/diagnosis ; Insulin/blood ; Insulinoma/diagnostic imaging/*pathology ; Magnetic Resonance Imaging ; Multiple Endocrine Neoplasia Type 1/*diagnosis/pathology ; Pancreatic Neoplasms/diagnostic imaging/*pathology ; Pedigree ; Polymorphism, Single Nucleotide ; Proto-Oncogene Proteins/genetics ; Seizures/complications

Objective To investigate the effects of miR-125a-5p on cell proliferation,apoptosis and cell cycle of pancreatic cancer cells.Methods The expression level of miR-125a-5p in pancreatic cancer was determined using quantitative real-time polymerase chain reaction analysis in 4 pairs of pancreatic cancer tissues and matched adjacent normal tissues samples. The expression of miR-125a-5p was downregulated in pancreatic cancer cell lines by transfection with miR-125a-5p inhibitor. Cell counting kit-8 assays was conducted to detect the growth ability of pancreatic cancer cell lines. Flow cytometry was applied to detect the cell cycle and apopotosis. Soft agar colony formation test was employed to assess the role of miR-125a-5p in process of malignant transformation.Results MiR-125a-5p was significantly highly expressed in pancreatic ductal adenocarcinoma tissues than adjacent normal tissues(P<0.05). After the expression level of miR-125a-5p in Panc-1 and MIA PaCa-2 was downregulated,the growth ability was suppressed(P<0.05),early apopotosis rate was promoted by 13.6% and 11.0% respectively(P<0.05),the amount of colony formation was reduced by 27.3% and 27.8%,respectively(P<0.05),and the percentage of S stage of Panc-1 was reduced by 11.8% (P<0.05).Conclusions The expression of miR-125a-5p is high in pancreatic ductal adenocarcinoma tissues. After the expression level of miR-125a-5p is downregulated,the growth ability,colony formation,and cell cycle of Panc-1 and MIA PaCa-2 are suppressed,and the early apopotosis rate will be promoted. Therefore,miR-125a-5p may play an oncogenic role in pancreatic ductal adenocarcinoma.
Apoptosis ; Carcinoma, Pancreatic Ductal ; pathology ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Cell Transformation, Neoplastic ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; Humans ; MicroRNAs ; genetics ; metabolism ; Pancreatic Neoplasms ; pathology

Animals ; Carrier Proteins ; genetics ; metabolism ; Cell Line, Tumor ; Insulinoma ; genetics ; metabolism ; pathology ; Mice ; Neoplasm Proteins ; genetics ; metabolism ; Pancreatic Neoplasms ; genetics ; metabolism ; pathology ; Phosphoproteins ; genetics ; metabolism

The expression levels of hypoxia-inducible factor 1alpha (HIF-1α) and HIF-2α in pancreatic cancer (PC) and their association with clinicopathologic characteristics were investigated in order to elucidate their roles in the development of PC. HIF-1α and HIF-2α mRNA levels in 20 patients with PC were detected by quantitative real-time polymerase chain reaction. The expression of HIF-1α and HIF-2α protein in samples from other 90 patients with PC was measured by immunohistochemistry. Correlations between the expression of HIF-1α or HIF-2α and clinicopathologica features and prognosis were analyzed. The expression of both HIF-1α and HIF-2α mRNA was up-regulated in most cancer tissues (P<0.05). HIF-1α staining was weakly positive in most cancer tissues and strongly positive in adjacent pancreas tissues (P<0.05). Clinicopathologic analysis revealed that relatively strong HIF-1α expression in cancer tissues was related to greater invasion (P<0.05), higher tumor pathologic stage (P<0.05), higher American Joint Committee on Cancer (AJCC) stage (P<0.05) and shorter overall survival time (P<0.05). Conversely, HIF-2α staining was strongly positive in most cancer tissues and weakly positive in adjacent pancreas tissues. Clinicopathologic analysis revealed that relatively strong HIF-2α expression in cancer tissues was related to less invasion (P<0.05), lower tumor pathologic stage (P<0.05), lower AJCC stage (P<0.05) and longer overall survival time (P<0.05). Moreover, the HIF-1α(high)/HIF-2α(low) group showed a shorter survival time than the HIF-1α(low)/HIF-2α(high) group. In conclusion, although HIF-1α and HIF-2α mRNA expression patterns are the same, their protein expression patterns are significantly different and they play different roles in PC. Combined analysis of HIF-1α and HIF-2α expression might be useful to predict the prognosis of patients with PC.
Basic Helix-Loop-Helix Transcription Factors ; genetics ; metabolism ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; genetics ; metabolism ; Pancreatic Neoplasms ; metabolism ; pathology ; Prognosis ; RNA, Messenger ; genetics

BACKGROUND/AIMS: MicroRNA (miRNA) regulates messenger RNA stability and translation. In cancer biology, miRNA affects the growth and metastasis of cancer cells by controlling epithelial-mesenchymal transition (EMT). MiR-200 family (200a/200b/200c/141) and miR-205 are associated with the regulation of EMT. We investigated the prognostic role of EMT-related miRNAs in pancreatic cancer. METHODS: We analyzed miR-200 family and miR-205 expression in tissue samples of 84 patients who underwent radical resection for pancreatic cancer. RESULTS: Patients were followed from the date of diagnosis until death or censoring. The mean overall survival was 25.0+/-2.0 months (2-140 months). The R0 resection rate was obtained in 84.5% (n=71) of patients. The relative expressions of miR-200a/200b/200c/141 and miR-205 were 266.9+/-57.3/18.5+/-2.2/0.7+/-0.1/27.2+/-6.6 folds and 0.1+/-0.1 compared with human pancreatic ductal epithelial cells, respectively. Overall survival was longer in the low miR-200c expression group than in the high expression group (35 vs. 19 months, p=0.013). Multivariate analysis confirmed that patients with low miR-200c expression survived longer than the high expression group (hazard ratio, 1.771; 95% CI, 1.081-2.900; p=0.023). There was a trend toward longer disease-free survival in low miR-200c group without statistical significance (p=0.061). CONCLUSIONS: The expression of miR-200c may be an important prognosis factor in pancreatic cancer, and it could be a novel therapeutic target of pancreatic cancer.
Adult ; Aged ; Aged, 80 and over ; Biomarkers, Tumor/genetics/*metabolism ; Disease-Free Survival ; Female ; Humans ; Male ; MicroRNAs/*metabolism ; Middle Aged ; Multivariate Analysis ; Pancreatic Neoplasms/*diagnosis/mortality/pathology ; Prognosis ; Proportional Hazards Models ; Real-Time Polymerase Chain Reaction ; Survival Rate

OBJECTIVE: To explore the eff ect of grape seed proanthocyanidins extract (GSPE) on the growth of pancreatic cancer cells and the underlying mechanisms. METHODS: The pancreatic cancer AsPC-1 cells were cultured in vitro. The effects of GSPE on cell proliferation, apoptosis and migration were analyzed by MTT, Annexin V-FITC/PI and Transwell migration assay, respectively. The expression of miR-27a and FOXO1 in AsPC-1 cells was determined by real-time RT-PCR and Western blot, respectively. The miR-27a inhibitors were applied to verify the role of miR-27a in mediation of GSPE effects. RESULTS: GSPE inhibited cell growth in a dose-dependent manner. This inhibitory effect was significant when the dosage of GSPE was more than 50 μg/mL (P<0.05 vs control). GSPE also could induce apoptosis and inhibit cell migration. MiR-27a expression was notably down-regulated when the dosage of GSPE was 75 μg/mL (P<0.01 vs control). Compared with the control group, cell proliferation inhibition was significantly increased in the miR-27a inhibitor group, the GSPE group and the miR-27a inhibitor plus GSPE group (P<0.01), while cell migration was significantly decreased (P<0.01). Compared with the GSPE or the miR-27a inhibitor group, the growth and migration inhibitory effects in the miR-27a inhibitor plus GSPE group were more obviously (P<0.01). Both GSPE and miR-27a inhibitor alone could up-regulate FOXO1 expression. But these effects were more apparent when they are applied in combination. CONCLUSION GSPE inhibites AsPC-1 cells' growth and migration partly through down-regulation of miR-27a expression.
Apoptosis ; Cell Line, Tumor ; drug effects ; Cell Movement ; Cell Proliferation ; Down-Regulation ; Grape Seed Extract ; pharmacology ; Humans ; MicroRNAs ; genetics ; metabolism ; Pancreatic Neoplasms ; pathology ; Proanthocyanidins ; pharmacology ; Up-Regulation