In the present study, we aimed to identify specific lncRNAs and miRNAs, as well as mRNAs, involved in bile duct carcinoma (BDC) and to further explore the way in which lncRNA UCA1 regulates cell metastasis ability. Differentially expressed RNAs were screened out from the TCGA database. In in vitro experiments, qRT-PCR was used to measure lncRNA UCA1, miR-122 and CLIC1 expression. We performed a dual luciferase assay to validate the target relationships among UCA1, CLIC1 and miR-122. The cell migration ability was measured by a wound healing assay, and Transwell assays were applied to detect cell invasive ability. Western blot analysis was employed to detect the expression of related proteins in the MAPK signaling pathway. According to the bioinformatics analysis, lncRNA UCA1 and CLIC1 were both significantly upregulated in BDC, while the expression of miR-122 declined compared with the normal group. The target relationship among UCA1, CLIC1 and miR-122 was verified. UCA1 promoted BDC cell migration and invasiveness, while miR-122 inhibited their progression. CLIC1 served as the downstream target gene of miR-122 and had opposite effects. The ERK/MAPK signaling pathway was activated after upregulating UCA1. LncRNA-UCA1 promoted the metastasis of BDC cells by regulating the expression of miR-122 and its downstream gene mRNA CLIC1 and promoted the activation of the ERK/MAPK pathway, which expanded the horizons of targeted therapy of cholangiocarcinoma.

To investigate the apoptosis and inflammatory response of microRNA‐27a‐5p (miR‐27a‐5p) in pancreatic acinar cells of acute pancreatitis (AP) and its related mechanisms. Rat pancreatic acinar cell line AR42J was treated with caerulein (10nmol/L) to construct an acute pancreatitis cell model. Quantitative real‐time polymerase chain reaction was performed to measure the expression of miR‐27a‐5p; The miR‐27a‐5p mimic was transfected into cell, and the apoptosis rate of the cells was detected by flow cytometry; The levels of TNF‐α, IL‐1, and IL‐6 in the culture supernatant were determined by enzyme‐linked immunosorbent assay; TargetScans database predicted and dual luciferase reporter gene assay verified the relationship between miR‐27a‐5p and the phosphatase and tensin homolog deleted on chromosome 10 (PTEN); The recovery experiment explored the apoptosis and the effects of inflammatory responses. The expression of miR‐27a‐5p decreased gradually (P < 0.05) and the expression of PTEN increased gradually (P < 0.05) with the prolongation of acting time. Upregulation of miR‐27a‐5p significantly promoted cell apoptosis (P < 0.05) and inhibited inflammatory response (P < 0.05); The TargetScans database predicted that the 3'UTR of PTEN contains a base complementary to the miR‐27a‐5p seed region. Cotransfection of wild‐type vector (PTEN‐WT) with miR‐27a‐5p mimic or miR‐27a‐5p inhibitor significantly affected the relative activity of luciferase (P < 0.05), and no significant impact was observed in mutant PTEN‐MUT. Compared with miR‐27a‐5p + pcDNA group, transfection of miR‐27a‐5p mimic and pcDNA‐PTEN significantly increased the expression of PTEN (P < 0.05), decreased the apoptotic rate (P < 0.05), and increased the inflammatory response (P < 0.05). miR‐27a‐5p induced apoptosis and inhibited the inflammatory response of pancreatic acinar cells in AP by targeting PTEN.

The present study aimed to investigate the long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) involved in the progression of gallbladder cancer and explore the potential physiopathologic mechanisms of gallbladder cancer in terms of competing endogenous RNAs (ceRNAs). The original lncRNA and mRNA expression profile data (nine gallbladder cancer tissues samples and nine normal gallbladder samples) in GSE76633 was downloaded from the Gene Expression Omnibus database. Differentially expressed mRNAs and lncRNAs between gallbladder cancer tissue and normal control were selected and the pathways in which they are involved were analyzed using bioinformatics analyses. MicroRNAs (miRNAs) were also predicted based on the differentially expressed mRNAs. Finally, the co-expression relation between lncRNA and mRNA was analyzed and the ceRNA network was constructed by combining the lncRNA-miRNA, miRNA-mRNA, and lncRNA-mRNA pairs.Overall, 373 significantly differentially expressed mRNAs and 47 lncRNAs were identified between cancer and normal tissue samples. The upregulated genes were significantly enriched in the extracellular matrix (ECM)-receptor interaction pathway, while the downregulated genes were involved in the complement and coagulation cascades. Altogether, 128 co-expression relations between lncRNA and mRNA were obtained. In addition, 196 miRNA-mRNA regulatory relations and 145 miRNA-lncRNA relation pairs were predicted. Finally, the lncRNA-miRNA-gene ceRNA network was constructed by combining the three types of relation pairs, such as XLOC_011309-miR-548c-3p-SPOCK1 and XLOC_012588-miR-765-CEACAM6. mRNAs and lncRNAs may be involved in gallbladder cancer progression via ECM-receptor interaction pathways and the complement and coagulation cascades. Moreover, ceRNAs such as XLOC_011309-miR-548c-3p-SPOCK1 and XLOC_012588-miR-765-CEACAM6 can also be implicated in the pathogenesis of gallbladder cancer. K E Y W O R D Scompeting endogenous RNA, gallbladder cancer, long noncoding RNA, messenger RNA, pathway

In the present study, we focused on the expression and biological functions of TMEM45B in pancreatic cancer tissues and cell lines. Real-time PCR and Western blotting were used to examine the expression levels of TMEM45B in pancreatic cancer tissues and cell lines. The functions of TMEM45B were evaluated using CCK-8, flow cytometry and transwell analysis. Our results showed that TMEM45B exhibited high expression in pancreatic cancer tissues and cell lines compared with the normal pancreatic tissues and cells. Using gene set enrichment analysis (GSEA), we found that TMEM45B may regulate multiple genes involved in the cell cycle and metastasis pathways. Downregulation of TMEM45B by RNA interference significantly reduced proliferation, invasion and migration of SW1990 and PANC-1 cells, accompanied by the induction of cell cycle arrest and apoptosis, whereas overexpression of TMEM45B promoted proliferation, invasion and migration of CFPAC-1 cells as well as apoptosis inhibition. Taken together, our study provides evidence that TMEM45B is an oncogene involved in the tumorigenesis of pancreatic cancer and may represent a new molecular target for pancreatic cancer treatment.

BackgroundPancreatic ductal adenocarcinoma (PDAC) is a highly malignant disease with a poor prognosis. More effective biomarkers and treatment options remain to be discovered. Mitotic Spindle Positioning (MISP), also called C19orf21, has been reported to be upregulated in several malignancies. However, the effects of MISP on PDAC have yet to be investigated.Materials and MethodsThe differential expression of MISP at the mRNA and protein levels were evaluated using Gene Expression Profiling Interactive Analysis 2 (GEPIA 2), Gene Expression Omnibus (GEO), and the Human Protein Atlas (HPA) databases, and was further verified by quantitative real-time PCR and western blotting in PDAC cell lines. Correlations between MISP expression and clinical characteristics were explored using Kaplan-Meier Plotter Database and clinical data from The Cancer Genome Atlas (TCGA). CCK-8 assays, Transwell assays, and immunoblotting were used to determine the role of MISP in PDAC proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in vitro. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were executed by the R package ‘clusterProfiler’. Correlations between MISP expression and immune cell infiltration, immune checkpoints, immunophenoscore (IPS) and the tumor mutational burden (TMB) in PDAC were explored using the R package ‘CIBERSORT’, the Tumor Immune Estimation Resource 2.0 (TIMER2.0), and The Cancer Immunome Atlas (TCIA) database based on TCGA data.ResultMISP expression was significantly higher in pancreatic cancer tissues compared to normal pancreas tissues, which was associated with a poor prognosis. Increased expression of MISP was related to the proliferation, migration and invasion of PDAC cell lines. GO and KEGG pathway analyses determined that MISP is involved in the Ras signaling pathway and immune regulation. Higher expression of MISP was associated with decreased infiltration levels of activated CD4+ memory T cells, CD8+ T cells, M2 macrophages and neutrophils. Furthermore, increased MISP was associated with lower expression of immune checkpoint molecules, higher gene mutation burden and IPS.ConclusionsThis study reveals that MISP, which is associated with the progression and prognosis of PDAC, may exert a potential regulatory effect on immune infiltration and predict the response to immunotherapy in PDAC.