miR-216b Targets FGFR1 and Confers Sensitivity to Radiotherapy in Pancreatic Ductal Adenocarcinoma Patients Without EGFR or KRAS Mutation

MicroRNAs: emerging biomarkers and therapeutic targets in pancreatic cancer

Pancreatic cancer (PC) is a highly malignant disease with high aggressiveness and a dismal prognosis, which is challenging to diagnose clinically early and gains low benefit from standard therapies. MicroRNAs (miRNAs) have become a hot topic in oncology research. Current evidence indicates that miRNAs are regulators involved in the entire process of PC, providing new diagnostic and therapeutic strategies for this fatal disease. Related research has been rapidly updated, making it necessary to review it to propose new directions and ideas and provide guidance for the development of precision medicine for PC. We reviewed the relevant literature through Pubmed, Embase, Web of Science and Medline, showing that abnormally expressed miRNAs in PC patients have the potential to be used as biomarkers for diagnosis and prognosis, highlighting the excellent prospect of combining miRNAs with traditional therapies, and the effective application of these factors for PC, especially miRNA mimics and inhibitors. MiRNAs participate in the entire process of PC and play important roles in diagnosis, treatment and prognosis. They are potential factors in conquering PC in the future.

The Role of miR-217-5p in the Puromycin Aminonucleoside-Induced Morphological Change of Podocytes

Podocytes, alternatively called glomerular epithelial cells, are terminally differentiated cells that wrap around glomerular capillaries and function as a part of the glomerular filtration barrier in the kidney. Therefore, podocyte injury with morphological alteration and detachment from glomerular capillaries leads to severe proteinuria and subsequent renal failure through glomerulosclerosis. Previous RNA sequencing analysis of primary rat podocytes exposed to puromycin aminonucleoside (PAN), a well-known experimental model of injured podocytes, identified several transcripts as being aberrantly expressed. However, how the expression of these transcripts is regulated remains unclear. MicroRNAs (miRNAs) are small noncoding RNAs that posttranscriptionally inhibit the expression of their target transcripts. In this study, using small RNA sequencing analysis, miR-217-5p was identified as the most upregulated transcript in PAN-treated rat podocytes. MiR-217-5p overexpression in E11 podocyte cells led to shrunken cells with abnormal actin cytoskeletons. Consistent with these changes in cell morphology, gene ontology (GO) enrichment analysis showed that interactive GO terms related to cell morphogenesis were enriched with the predicted targets of miR-217-5p. Of the predicted targets highly downregulated by PAN, Myosin 1d (Myo1d) is a nonmuscle myosin predicted to be involved in actin filament organization and thought to play a role in podocyte morphogenesis and injury. We demonstrated that miR-217-5p targets Myo1d by luciferase assays, qRT–PCR, and Western blotting. Furthermore, we showed that miR-217-5p was present in urine from PAN- but not saline-administrated rats. Taken together, our data suggest that miR-217-5p may serve as a therapeutic target and a biomarker for podocyte injury.

Syntenin Regulated by miR-216b Promotes Cancer Progression in Pancreatic Cancer

Outcomes for patients with pancreatic cancer (PC) are poor; therefore, there is an urgent need to identify novel therapeutic targets involved in the progression of PC. We previously identified 161 differentially expressed proteins (DEPs) in PC. Syntenin (SDCBP) was identified as a survival-related protein through integrated, survival, and Cox analyses. High expression of SDCBP was associated with a poor prognosis in PC tissue and promoted the proliferation, migration, and invasion of PC cells, and induced epithelial–mesenchymal transition (EMT) via the PI3K/AKT pathway. Additionally, we elucidated the regulatory mechanism underlying these roles of SDCBP at the post-transcriptional level. microRNAs (miRNAs) of SDCBP were predicted using bioinformatics. Low levels of miR-216b expression were confirmed in PC tissues and were negatively correlated with SDCBP expression. miR-216b was found to directly regulate SDCBP expression through luciferase reporter assays. Furthermore, agomiR-216b restrained PC proliferation, migration, invasion, and EMT via the PI3K/AKT pathway, whereas antagomiR-216b facilitated this process. Notably, the knockout of SDCBP counteracted the effect of antagomiR-216b in PC, which suggested that miR-216b and SDCBP represent molecular targets underlying PC progression and EMT. Finally, the results were validated in in vivo studies. These findings indicated that low expression of miR-216b and the oncogene SDCBP contributes to PC migration, invasion, and EMT, and that they have potential as future therapeutic targets for patients with PC.

LncRNA LINC00857 strengthens the malignancy behaviors of pancreatic adenocarcinoma cells by serving as a competing endogenous RNA for miR-340-5p to upregulate TGFA expression

Background

Pancreatic adenocarcinoma (PAAD) is a pancreatic disease with a high mortality rate in the world. This present research intends to identify the function of lncRNA LINC00857/miR-340-5p/Transforming growth factor alpha (TGFA) in the progression of PAAD.

Methods

Bioinformatics analysis was used to explore the differentially expressed lncRNA/miRNA/mRNA and analyze the relationship between lncRNA/miRNA/mRNA expression and prognosis of PAAD by enquiring TCGA, GEO and GTE_X. KEGG pathway analysis and GO enrichment analysis were implemented to annotate the crucial genes regulated by LINC00857. The biological behaviors of PAAD cells were detected by CCK-8, colony formation and transwell assays. Interactive associations between LINC00857 and miR-340-5p, as well as miR-340-5p and TGFA were analyzed by dual luciferase assay.

Results

By enquiring TCGA database, we got that LINC00857 was highly expressed in patients with PAAD and positively associated with worse prognosis in PAAD patients. Moreover, LINC00857 upregulation promoted the proliferation and clone formation abilities of PAAD cells. Afterwards, the downstream miRNA and mRNA targets of LINC00857 were picked up to construct a ceRNA network. Further study revealed that TGFA expression was positively regulated by LINC00857 and negatively regulated by miR-340-5p. Besides that, the inhibitory effect of miR-340-5p on PAAD cells growth and movement can be blocked by LINC00857 upregulation. While, the malignant behavior of PAAD cells induced by TGFA overexpression can be eliminated by LINC00857 knockdown.

Conclusions

Upregulation of LINC00857 improved growth, invasion and migration abilities of PAAD cells by modulation of miR-340-5p/TGFA, affording potential targets and biomarkers for the clinical diagnosis and treatment.

Long noncoding RNA LINC00657 enhances the malignancy of pancreatic ductal adenocarcinoma by acting as a competing endogenous RNA on microRNA-433 to increase PAK4 expression

A long noncoding RNAs (lncRNA) called LINC00657 is dysregulated and contributes to tumor progression in a number of human cancer types. However, there is limited information on the expression profile and functions of LINC00657 in pancreatic ductal adenocarcinoma (PDAC). The expression profile of LINC00657 in PDAC was estimated by reverse-transcription quantitative polymerase chain reaction (RT-qPCR). The effects of LINC00657 upregulation on PDAC cell proliferation, apoptosis, migration, and invasion in vitro and tumor growth in vivo were explored using CCK-8, flow cytometry, Transwell migration and invasion assays, and a xenograft tumor formation experiment, respectively. The results revealed that LINC00657 was evidently upregulated in the PDAC tumors and cell lines. High LINC00657 expression significantly correlated with the pathological T stage, lymph node metastasis, and shorter overall survival. Functional analysis demonstrated that LINC00657 knockdown inhibited the proliferation, migration, and invasion while promoted the apoptosis of PDAC cells. In addition, LINC00657 knockdown markedly suppressed tumor growth of these cells in vivo. In terms of the mechanism, LINC00657 could directly interact with microRNA-433 (miR-433) and effectively worked as an miR-433 sponge, thus decreasing the competitive binding of miR-433 to PAK4 mRNA and ultimately increasing PAK4 expression. The actions of LINC00657 knockdown on malignant phenotype of PDAC cells were strongly attenuated by miR-433 inhibition and PAK4 restoration. These results indicate that LINC00657 promotes PDAC progression by increasing the output of the miR-433-PAK4 regulatory loop, thus highlighting the importance of the LINC00657-miR-433-PAK4 network in PDAC pathogenesis.

Upregulation of long noncoding TNFSF10 contributes to osteoarthritis progression through the miR-376-3p/FGFR1 axis

Osteoarthritis (OA) is a common joint disease with high morbidity, but there is still no definitive treatment for it. Long noncoding RNAs (lncRNAs) have been confirmed to play key roles in OA progression. This work was done to investigate the roles and action mechanism of lncRNA TNFSF10 in OA. The messenger RNA levels of TNFSF10 in articular cartilage samples from patients or chondrocytes were detected by Quantitative real-time PCR assay (qRT-PCR). The effects of TNFSF10 on chondrocytes were evaluated on the basis of cell growth, apoptosis, and inflammation. Then, the interaction between TNFSF10 and miR-376-3p was explored by dual-luciferase reporter test, RNA-binding protein immunoprecipitation, and RNA pull-down assay. Finally, various cell experiments, Western blot analysis, and qRT-PCR were performed to study the interaction among TNFSF10, miR-376-3p, and fibroblast growth factor receptor 1 (FGFR1). It was found that TNFSF10 was upregulated in OA cartilages and stimulated cell proliferation, antiapoptosis, and inflammation for chondrocytes. In addition, TNFSF10 acted as a competing endogenous RNA to downregulate miR-376-3p, and the influence of TNFSF10 on chondrocytes was partly reversed by miR-376-3p. Moreover, FGFR1, as a target of miR-376-3p, had reversal functions on the outcomes mediated by miR-376-3p. The further analysis displayed that there was a negative relationship between TNFSF10 and miR-376-3p as well as miR-376-3p and FGFR1, while FGFR1 was positively related with TNFSF10. Altogether, TNFSF10 overexpression probably stimulated proliferation and inflammation, and inhibited apoptosis by regulating the miR-376-3p/FGFR1 axis, implying that its increase contributed to OA progression. Our study provided a new potential biomarker or therapeutic target-TNFSF10, which was helpful to develop an efficient approach to cure OA.

Genomic profiling in pancreatic ductal adenocarcinoma and a pathway towards therapy individualization: A scoping review

CONTEXT

Pancreatic cancer (PDAC) is one of the most challenging cancers to treat with modest recent improvements in survival from new systemic therapies. There is growing interest in individualized therapy underpinned by somatic and germline genomic alterations.

OBJECTIVE

A systematic review of data on therapies targeting somatic and germline alterations, and their downstream pathways in PDAC.

METHOD

A systematic literature search was conducted using PRISMA guidelines to include relevant results published after January 1, 2008.

RESULTS

A total of 71 relevant studies were included. We identified 36 studies targeting the KRAS-pathway, the most common being with MEK-inhibitor therapy. Twenty-two studies were identified that evaluated platinum-based chemotherapy and PARP inhibitors in patients with deleterious mutations in DNA damage repair genes and have shown encouraging results. Immunotherapy has demonstrated activity in patients with mismatch repair deficiency/microsatellite instability.

CONCLUSION

Evidence from translational and clinical research presents an exciting platform for genomic targeted therapy in PDAC. Validity for targeting BRCA with platinum and PARP inhibitors and microsatellite instability with immune therapy has been established, nonetheless, evidence for targeting the common driver oncogenes is lacking and much work is needed. Of importance is identifying the subgroup of KRAS -wild type PDAC (approximately 5%) where there is enrichment for targetable opportunities.

Identification of Six Potentially Long Noncoding RNAs as Biomarkers Involved Competitive Endogenous RNA in Clear Cell Renal Cell Carcinoma

Background. Clear cell renal cell carcinoma (ccRCC), the most common subtype of renal cell carcinoma (RCC), usually is representative of metastatic heterogeneous neoplasm that links with poor prognosis, but the pathogenesis of ccRCC remains unclear. Currently, numerous evidences prove that long noncoding RNAs (lncRNAs) are considered as competing endogenous RNA (ceRNA) to participate in cellular processes of tumors. Therefore, to investigate the underlying mechanisms of ccRCC, the expression profiles of lncRNAs, miRNAs, and mRNAs were downloaded from the Cancer Genome Atlas (TCGA) database. A total of 1526 differentially expressed lncRNAs (DElncRNAs), 54 DEmiRNAs, and 2352 DEmRNAs were identified. To determine the connection of them, all DElncRNAs were input to the miRcode database. The results indicated that 85 DElncRNAs could connect with 9 DEmiRNAs in relation to our study. Then, databases of TargetScan and miRDB were used to search for targeted genes with reference to DEmiRNAs. The results showed that 203 out of 2352 targeted genes were identified in our TCGA set. Subsequently, ceRNA network was constructed according to Cytoscape and the targeted genes were functionally analyzed to elucidate the mechanisms of DEmRNAs. The results of survival analysis and regression analysis indicated that 6 DElncRNAs named COL18A1-AS1, WT1-AS, LINC00443, TCL6, AL356356.1, and SLC25A5-AS1 were significantly correlative with the clinical traits of ccRCC patients and could be served as predictors for ccRCC. Finally, these findings were validated by quantitative RT-PCR (qRT-PCR). Based on these discoveries, we believe that this identified ceRNA network will provide a novel perspective to elucidate ccRCC pathogenesis.

MiR-216b inhibits pancreatic cancer cell progression and promotes apoptosis by down-regulating KRAS

INTRODUCTION

Pancreatic cancer is a highly lethal malignancy with high invasion metastasis, which is difficult to diagnose and treat. MicroRNA-216b (miR-216b) plays an important role in many types of tumors. In this study, we explore how miR-216b affected human pancreatic cancer cell development by targeting KRAS.

MATERIAL AND METHODS

Expression level of miR-216b and KRAS in tissue samples and cells were detected by RT-PCR and western blot. Immunohistochemical assay analysed the expressions of KRAS protein in tumor and adjacent tissues. The target relationship between miR-216b and KRAS was validated by dual-luciferase reporter assay. Pancreatic cancer cell proliferation, migration, invasion and apoptosis abilities of cells transfected with miR-216b mimics and KRAS-siRNA, Panc-1 were detected by MTT assay, transwell assay and flow cytometry assay respectively. Prognosis of patients with different expression levels of miR-216b and KRAS were analyzed by Kaplan-Meier survival analysis and Cox proportional hazards regression model.

RESULTS

The expression of miR-216b in pancreatic cancer tissue and cell line was down-regulated (p < 0.01), while KRAS expression was up-regulated (p < 0.01) compared with adjacent normal tissues. Both the expressions of miR-216b and KRAS have a strong influence on prognosis of the pancreatic cancer patients (p = 0.024 and p = 0.017). The dual-luciferase reporter assay verified that miR-216b directly targeted KRAS in pancreatic cancer cells. Overexpression of miR-216b reduced the expression of mRNA and protein of KRAS (p = 0.013 and p = 0.003), but silencing KRAS had no effect on miR-216b expression (p = 0.706). By silencing KRAS or up-regulation of miR-216b could suppress cell proliferation, migration and invasion of pancreatic cancer cells and promote apoptosis.

CONCLUSIONS

MiR-216b might inhibit pancreatic cancer cell progression and stimulate apoptosis by silencing KRAS.

Overexpression of the Long Noncoding RNA HomeoboxA Transcript at the Distal Tip Predicts Poor Prognosis in a KRAS-Independent Manner in Periampullary Region Tumors

OBJECTIVES

Periampullary region tumors (PRTs) are the fifth highest cause of cancer-related deaths worldwide. Although recent studies have highlighted the prognostic value of the long noncoding RNA HomeoboxA transcript at the distal tip (HOTTIP) in patients with pancreatic ductal adenocarcinoma, the relationship between HOTTIP and clinical outcome of all PRTs remains obscure. The aim of this study was to clarify the prognostic significance of HOTTIP in patients with all PRTs related to KRAS mutational status.

METHODS

HomeoboxA transcript at the distal tip expression was detected in 100 PRT samples using quantitative real-time polymerase chain reaction. The associations between HOTTIP levels, clinicopathological factors, and patient prognosis were also analyzed.

RESULTS

The expression of HOTTIP was found to be significantly upregulated by 32-fold (P = 0.031) in tumor tissues compared with normal tissues. The over expression of HOTTIP was related with presence of invasion and metastasis (P = 0.0467, P = 0.0256). In addition, increased HOTTIP expression was associated with poor prognosis independent of KRAS mutation (P < 0.001; n = 72). Moreover, multivariate analysis showed that high HOTTIP expression was an unfavorable prognostic factor for overall survival.

CONCLUSIONS

Our findings indicate that high levels of HOTTIP expression have the potential to be an independent, unfavorable prognostic factor for patients with PRT.

miR-216b inhibits glioma cell migration and invasion through suppression of FoxM1

MicroRNAs (miRNAs) play a vital role in tumour biological and pathologic processes. In the present study, we aimed to detect the expression and biological role of miR-216b in glioma. Our data showed that miR-216b was significantly downregulated in human glioma tissues and cells. Ectopic expression of miR-216b inhibited the proliferation and invasion of U87 and U251 cells and suppressed the growth of xenograft tumours in vivo. Bioinformatic and luciferase reporter analyses identified Forkhead box protein M1 (FoxM1) as a direct target of miR-216b. Overexpression of miR-216b inhibited the expression of FoxM1 in glioma cells. Rescue experiments demonstrated that co-transfection of FoxM1 lacking the 3'-untranslated region partially prevented miR‑216b-induced inhibition of glioma cell growth and invasion. In vivo studies indicated that ectopic expression of miR-216b impeded the proliferation of glioma xenograft tumours in nude mice, coupled with a decreased in FoxM1 protein expression and the percentage of Ki-67-positive tumour cells. Taken together, our results provide evidence of the suppressive activity of miR‑216b in glioma, which is largely ascribed to downregulation of FoxM1. Restoration of miR-216b may provide a novel potential therapeutic agent for glioma.

MicroRNA-216b-5p Functions as a Tumor-suppressive RNA by Targeting TPT1 in Pancreatic Cancer Cells

MicroRNAs (miRNAs) are increasingly recognized as being involved in pancreatic cancer progression by directly regulating the expression of their targets. In this study, we showed that miR-216b-5p expression was significantly decreased in pancreatic cancer tissues and cell lines. In addition, low miR-216b-5p expression was significantly associated with large tumor size and advanced TNM stage. Meanwhile, both Kaplan-Meier and multivariate survival analysis showed that decreased miR-216b-5p expression was associated with overall survival. miR-216b-5p over-expression repressed pancreatic cancer cell proliferation and induced cell cycle arrest and cell apoptosis in vitro and inhibited tumorigenesis in vivo. The translationally controlled tumor protein (TPT1) was identified as a novel direct target of miR-216b-5p. miR-216b-5p up-regulation suppressed TPT1 expression. Moreover, TPT1 mRNA expression levels were increased in pancreatic cancer tissues, and were inversely correlated with miR-216b-5p expression. TPT1 down-regulation had similar effects as miR-216b-5p up-regulation on pancreatic cancer cell progression. The restoration of TPT1 reversed the effect of miR-216b-5p on pancreatic cancer cell progression. Furthermore, we found that miR-216b-5p up-regulation suppressed Pim-3, Cyclin B1, p-Bad and Bcl-xL protein expression. However, the effect of miR-216b-5p up-regulation was partly reversed by TPT1 up-regulation in vitro. Taken together, our findings suggested that miR-216b-5p functions as a potential tumor suppressor by regulating TPT1 in pancreatic cancer cells, and it may represent a potential therapeutic target for patients with pancreatic cancer.

Regulation of UGT2B Expression and Activity by miR-216b-5p in Liver Cancer Cell Lines

The UDP-glucuronosyltransferase (UGT) 2B enzymes are important in the detoxification of a variety of endogenous and exogenous compounds, including many hormones, drugs, and carcinogens. Identifying novel mechanisms governing their expression is important in understanding patient-specific response to drugs and cancer risk factors. In silico prediction algorithm programs were used to screen for microRNAs (miRNAs) as potential regulators of UGT2B enzymes, with miR-216b-5p identified as a potential candidate. Luciferase data suggested the presence of a functional miR-216b-5p binding motif within the 3' untranslated regions of UGTs 2B7, 2B4, and 2B10. Overexpression of miR-216b-5p mimics significantly repressed UGT2B7 (P < 0.001) and UGT2B10 (P = 0.0018) mRNA levels in HuH-7 cells and UGT2B4 (P < 0.001) and UGT2B10 (P = 0.018) mRNA in Hep3B cells. UGT2B7 protein levels were repressed in both HuH-7 and Hep3B cells in the presence of increasing miR-216b-5p concentrations, corresponding with significant (P < 0.001 and P = 0.011, respectively) decreases in glucuronidation activity against the UGT2B7-specific substrate epirubicin. Inhibition of endogenous miR-216b-5p levels significantly increased UGT2B7 mRNA levels in HuH-7 (P = 0.021) and Hep3B (P = 0.0068) cells, and increased epirubicin glucuronidation by 85% (P = 0.057) and 50% (P = 0.012) for HuH-7 and Hep3B cells, respectively. UGT2B4 activity against codeine and UGT2B10 activity against nicotine were significantly decreased in both HuH-7 and Hep3B cells (P < 0.001 and P = 0.0048, and P = 0.017 and P = 0.043, respectively) after overexpression of miR-216b-5p mimic. This is the first evidence that miRNAs regulate UGT 2B7, 2B4, and 2B10 expression, and that miR-216b-5p regulation of UGT2B proteins may be important in regulating the metabolism of UGT2B substrates.