Hypoxia mediates immune escape of pancreatic cancer cells by affecting miR-1275/AXIN2 in natural killer cells.

Given the increasing incidence of pancreatic cancer and the low survival rate, the exploration of the complex tumor microenvironment and the development of novel treatment options is urgent. NK cells, known for their cytotoxic abilities and modulation of other immune cells, are vital in recognizing and killing cancer cells. However, hypoxic conditions in the tumor microenvironment have been found to impair NK cell functionality and contribute to tumor immune escape. Therefore, we aimed to uncover the mechanism through which hypoxia mediates the immune escape of pancreatic cancer cells, focusing on the influence of miR-1275/AXIN2 on NK cells. Using a combination of GEO dataset screening, Tumor Immune Estimation Resource 2.0 immunoscore screening, and the Cancer Genome Atlas data, we identified a correlation between miR-1275 and NK cells. The down-regulation of miR-1275 was associated with decreased NK cell activity and survival in patients with pancreatic cancer. Pathway analysis further linked miR-1275 expression with the hypoxic HIF1A pathway. In vitro experiments were conducted using the NK-92 cell, revealing that hypoxia significantly reduced miR-1275 expression and correspondingly decreased the cell-killing ability of NK cells. Upregulation of miR-1275 increased perforin, IFN-γ and TNF-α expression levels and enhanced NK cell cytotoxicity. Additionally, miR-1275 was found to bind to and inhibit AXIN2 expression, which when overexpressed, partially alleviated the promotive effect of upregulated miR-1275 on NK-92 cell killing ability. In conclusion, this research underscores the critical role of the miR-1275/AXIN2 axis in hypoxia-mediated immune escape in pancreatic cancer, thus opening new potential avenues for treatment strategies.

Incidence trends and survival analysis of appendiceal tumors in the United States: Primarily changes in appendiceal neuroendocrine tumors.

BACKGROUND: Appendiceal tumors are considered to be a relatively rare tumor of the gastrointestinal tract and the prognosis is unclear. This study comprehensively investigated trends in the epidemiology and survival of appendiceal tumors in the United States over the past approximately 20 years. METHODS: Patients with pathologically confirmed appendiceal tumors from 2000 to 2017 were selected from the Surveillance, Epidemiology and End Results (SEER) database. Age-adjusted incidence rates were calculated by SEER*Stat 8.4.0. The Kaplan-Meier method was used to analyze survival and prognostic factors were investigated by a multivariate Cox proportional risk model. RESULTS: Ultimately, 13,546 patients with appendiceal tumors between 2000 and 2017 were included. The annual incidence of colonic adenocarcinoma and mucinous adenocarcinoma remained relatively stable. Interestingly, the annual incidence of appendiceal neuroendocrine tumors (aNETs) increased significantly, from 0.03 to 0.90 per 100,000 person-years, with the most dramatic increase in the number of patients with localized disease. Patients with aNETs showed a significant improvement in survival between 2009-2017, compared to the period 2000-2008. Moreover, this improvement in survival over time was seen at all stages (localized, regional, distant) of aNETs. However, this improved survival over time was not seen in colonic and mucinous adenocarcinoma. CONCLUSIONS: The incidence of appendiceal neoplasms has increased significantly over the past nearly two decades, which is mainly due to the increased incidence and significant migration to earlier stages in aNETs. We must note that despite the increased incidence of aNETs, survival rates have improved at different disease stages.

miR-146b-5p downregulates IRAK1 and ADAM19 to suppress trophoblast proliferation, invasion, and migration in miscarriage†.

A large proportion of miscarriages are classified as unexplained miscarriages since no cause is identified. No reliable biomarkers or treatments are available for these pregnancy losses. While our transcriptomic sequencing has revealed substantial upregulation of miR-146b-5p in unexplained miscarriage villous tissues, its role and associated molecular processes have yet to be fully characterized. Our work revealed that relative to samples from normal pregnancy, miR-146b-5p was significantly elevated in villous tissues from unexplained miscarriage patients and displayed promising diagnostic potential. Moreover, miR-146b-5p agomir contributed to higher rates of embryonic resorption in ICR mice. When overexpressed in HTR-8/SVneo cells, miR-146b-5p attenuated the proliferative, invasive, and migratory activity of these cells while suppressing the expression of MMP9 and immune inflammation-associated cytokines, including IL1B, IL11, CXCL1, CXCL8, and CXCL12. Conversely, inhibition of its expression enhanced proliferation, migration, and invasion abilities. Mechanistically, IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19 were identified as miR-146b-5p targets regulating trophoblast function, and silencing IL-1 receptor-associated kinase-1 had similar effects as miR-146b-5p overexpression, while IL-1 receptor-associated kinase-1 overexpression could partially reverse the inhibitory impact of this microRNA on trophoblasts. miR-146b-5p may inhibit trophoblast proliferation, migration, invasion, and implantation-associated inflammation by downregulating IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19, participating in the pathogenesis of miscarriage and providing a critical biomarker and a promising therapeutic target for unexplained miscarriage.

Hypoxia promotes immune escape of pancreatic cancer cells by lncRNA NNT-AS1/METTL3-HuR-mediated ITGB1 m6A modification.

Pancreatic cancer (PC) cell immune escape is a crucial element in PC malignant development. Some previous studies have reported that LncRNA NNT-AS1 played a carcinogenic role in various tumors. However, the effect of lncRNA NNT-AS1 in PC cell immune escape remains unclear. To evaluate PC cell immune escape, PC cells were co-cultured with CD8+ T cells under a hypoxic condition. PC cell proliferation and migration were evaluated using the colony formation assay and transwell assay. CD8+ T cell proliferation and aoptosis were measured using the carboxy fluorescein diacetate succinimidyl ester (CFSE) assay and flow cytometry. The secretion of antitumor cytokines was assessed using enzyme-linked immunosorbent assay (ELISA). The molecular interactions were analyzed using chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP), or dual-luciferase reporter gene assays. A tumor xenograft model was established to evaluate the effects of lncRNA NNT-AS1 on PC in vivo. It was found that lncRNA NNT-AS1 was highly expressed in PC, and its silencing inhibited hypoxia-induced PC cell growth and immune escape in vivo and in vitro. Mechanically, HIF-1α transcriptionally activated NNT-AS1 expression and NNT-AS1 increased ITGB1 stability and expression in a METTL3-HuR dependent manner. ITGB1 overexpression reversed the inhibitory effects of NNT-AS1 knockdown on hypoxia-induced PC cell immune escape. In conclusion, Hypoxia promoted PC cell immune escape through lncRNA NNT-AS1/METTL3-HuR-mediated m6A modification to increase ITGB1 expression, which provided a theoretical foundation and a potential therapeutic target for PC.

Identification of significant prognostic risk markers for pancreatic ductal adenocarcinoma: a bioinformatic analysis.

OBJECTIVE: This study aimed to identify novel prognostic biomarkers of pancreatic ductal adenocarcinoma (PDAC) using bioinformatics analyzes. METHODS: Clinical information, microRNAs (miRNAs), and genes expression profile data from PDAC cases were downloaded from the Cancer Genome Atlas (TCGA) database. The potential prognostic risk miRNAs and genes were screened using the Elastic Net Cox proportional risk regression hazards (EN-COX) model. The receiver operating characteristic (ROC) curve and the Kaplan-Meier (KM) curve were used to identify miRNAs and genes of significant prognostic risk. Furthermore, significant prognostic risk miRNAs were functional enrichment analyses based on their target genes. Furthermore, the survival analyzes of the hub genes were validated through OncoLnc. RESULTS: Complete clinical records and expression data of 797 miRNAs and 19969 genes from 137 PDAC cases were obtained, of which 59 potential prognostic risk factors, including 54 genes and 5 miRNAs, were selected by EN-COX analyzes. A total of 17 significant prognostic risk markers were identified (all P<0.05), including 16 genes and 1 miRNA (miRNA-125a). The miRNA-125a target genes were found in the MiRWalk database and the function enrichment analyzes were performed in the the DAVID website. Furthermore, according to data from the Oncomine and Human Protein Atlas (HPA) databases, the mRNA and protein level of frizzled class receptor 8 (FZD8) were overexpressed in pancreatic cancer tissues compared to the corresponding noncancer normal tissues (P<0.001). However, both glutathione S-transferase mu 4 (GSTM4) and inducible T cell costimulator ligand (ICOSLG) were negatively regulated in tissues of pancreatic cancer tissues (P<0.001). Finally, survival analysis was used to validate these factors by the OncoLnc database, and the results revealed that overexpression of ICOSLG was associated with a better prognosis (P=0.025). CONCLUSIONS: This study showed that the expression levels of FZD8, GSTM4 and ICOSLG were significantly different between PDAC and non-tumor tissues, especially ICOSLG, which could be a prognostic indicator and therapeutic target for PDAC.

MiR-135a-5p suppresses trophoblast proliferative, migratory, invasive, and angiogenic activity in the context of unexplained spontaneous abortion.

BACKGROUND: Spontaneous abortions (SA) is amongst the most common complications associated with pregnancy in humans, and the underlying causes cannot be identified in roughly half of SA cases. We found miR-135a-5p to be significantly upregulated in SA-associated villus tissues, yet the function it plays in this context has yet to be clarified. This study explored the function of miR-135a-5p and its potential as a biomarker for unexplained SA. METHOD: RT-qPCR was employed for appraising miR-135a-5p expression within villus tissues with its clinical diagnostic values being assessed using ROC curves. The effects of miR-135a-5p in HTR-8/SVneo cells were analyzed via wound healing, Transwell, flow cytometry, EdU, CCK-8, and tube formation assays. Moreover, protein expression was examined via Western blotting, and interactions between miR-135a-5p and PTPN1 were explored through RIP-PCR, bioinformatics analyses and luciferase reporter assays. RESULTS: Relative to normal pregnancy (NP), villus tissue samples from pregnancies that ended in unexplained sporadic miscarriage (USM) or unexplained recurrent SA (URSA) exhibited miR-135a-5p upregulation. When this miRNA was overexpressed in HTR-8/SVneo cells, their migration, proliferation, and cell cycle progression were suppressed, as were their tube forming and invasive activities. miR-135a-5p over-expression also downregulated the protein level of cyclins, PTPN1, MMP2 and MMP9. In RIP-PCR assays, the Ago2 protein exhibited significant miR-135a-5p and PTPN1 mRNA enrichment, and dual-luciferase reporter assays indicated PTPN1 to be a bona fide miR-135a-5p target gene within HTR-8/SVneo cells. CONCLUSION: miR-135a-5p may suppress trophoblast migratory, invasive, proliferative, and angiogenic activity via targeting PTPN1, and it may thus offer value as a biomarker for unexplained SA.

Placental transcriptome sequencing combined with bioinformatics predicts potential genes and circular RNAs associated with hemoglobin Bart's hydrops fetalis syndrome.

AIM: Hemoglobin Bart's hydrops fetalis syndrome (BHFS) is the most severe form of α-thalassemia. Histological alternations can be observed in placenta, but placental transcriptome profile and circular RNAs have not been studied in this disease. The aim of this study was to define the placental transcriptional changes and find relevant circular RNAs in BHFS. METHODS: We performed high-throughput RNA sequencing to detect placental samples from fetuses affected by BHFS (n = 5) and normal fetuses (NF, n = 5), quantitative reverse transcription polymerase chain reaction (RT-qPCR), and Sanger sequencing to validate the differentially expressed circRNAs and their potentially related miRNAs (BHFS, n = 22; NF, n = 11). Bioinformatics methods were performed for further analysis. RESULTS: Our results showed 152 differentially expressed genes (DEGs), 112 circRNAs, and 45 microRNAs that were differentially expressed. DEGs were found to be involved in Gene Ontology terms related to gas transport, cell adhesion, oxidative stress, organ development, hemopoiesis, and others. RT-qPCR results showed that hsa_circ_0003961 and hsa_circ_0006687 were upregulated (p < 0.05). The competing endogenous RNA and co-expression networks showed that hsa_circ_0003961 and hsa_circ_0006687 were connected with 3 miRNAs and some DEGs, including cell adhesion genes (e.g., CLDN19), hemoglobin related genes (e.g., SOX6 and HBZ) and angiogenesis related genes (e.g., EPHB2). Downregulations of hsa-miR-1299 and hsa-miR-625-5p in ceRNA network were also validated by RT-qPCR. Gene set enrichment analysis results for the two circRNAs showed that some gene sets associated with cell adhesion, hematopoietic system and apoptosis were significantly enriched. CONCLUSIONS: Our study characterized the placental transcriptome of BHFS. The circRNAs hsa_circ_0003961 and hsa_circ_0006687 in placenta may be relevant to BHFS.

Corrigendum to "Long Noncoding RNA TUG1/miR-29c Axis Affects Cell Proliferation, Invasion, and Migration in Human Pancreatic Cancer".

[This corrects the article DOI: 10.1155/2018/6857042.].

Long non-coding RNA HULC as a diagnostic and prognostic marker of pancreatic cancer.

BACKGROUND: Long non-coding RNA (lncRNA) is abnormally expressed in various malignant tumors. In recent years, it has been found that IncRNA HULC is increasingly expressed in pancreatic cancer tissues and is involved in the development and progression of pancreatic cancer. However, the clinical value of serum HULC in pancreatic cancer remains unclear, and there are few studies on how HULC regulates the biological function of pancreatic cancer cells. AIM: To determine the value of lncRNA HULC in the diagnosis and prognosis of pancreatic cancer, and its possible biological potential. METHODS: Sixty patients with pancreatic cancer and sixty patients with benign pancreatic diseases admitted to Xiangya Hospital, Central South University were assigned to the pancreatic cancer group and the benign disease group, respectively, and another 60 healthy subjects were enrolled as the normal group during the same period. HULC-siRNA and NC-siRNA were transfected into pancreatic cancer cells. Quantitative real-time polymerase chain reaction was performed to determine the expression of HULC in tissues, serum, and cells. Western Blot was carried out to determine the expression of ß-catenin, c-myc, and cyclin D1 in cells, and the cell counting kit-8, flow cytometry, and Transwell assay were conducted to determine the proliferation, apoptosis and invasion of cells. RESULTS: Highly expressed in the tissues and serum of pancreatic cancer patients, HULC showed good clinical value in distinguishing between patients with pancreatic cancer, patients with benign pancreatic diseases and healthy subjects. HULC was related to pathological parameters including tumor size, T staging, M staging and vascular invasion, and the area-under-the-curve for evaluating these four parameters was 0.844, 0.834, 0.928 and 0.818, respectively. Patients with low expression of HULC had a significantly higher 3-year overall survival (OS) and 5-year OS than those with high expression. T staging, M staging, vascular invasion, and HULC were independent prognostic factors affecting the 3-year OS of patients with pancreatic cancer. Inhibition of HULC expression prevented the proliferation and invasion of pancreatic cancer cells, promoted apoptosis, and inhibited the expression of Wnt/ß-catenin signaling pathway-related proteins, ß-catenin, c-myc, and cyclin D1. The Wnt/ß-catenin signaling pathway agonist (LiCl) restored proliferation, apoptosis, and invasion of pancreatic cancer cells with inhibited expression of HULC. CONCLUSION: HULC is an effective marker for the diagnosis and prognosis of pancreatic cancer, which may affect the biological function of pancreatic cancer cells through the Wnt/ß-catenin signaling pathway.

Hypoxia-induced shedding of MICA and HIF1A-mediated immune escape of pancreatic cancer cells from NK cells: role of circ_0000977/miR-153 axis.

One key to malignant progression of pancreatic cancer (PC) is the acquired ability of tumour cells to escape immune-mediated lysis. Hypoxic microenvironment plays a causal role in PC metastasis. According to previous studies, hypoxia could induce the upregulation of HIF1A, ADAM10 and sMICA, leading to decreased NKG2D in NK cells and tumour cells escape from immune surveillance and NK cell-mediated lysis. In the present study, in NK cells derived from high-HIF1A expression patients, the levels of internalization of MICA/B and NKG2D were obviously higher than those in low-HIF1A expression group; hypoxia dramatically upregulated the levels of sMICA culture supernatant of Panc-1 cells. Regarding the molecular mechanism, dysregulated circRNAs and miRNAs that might modulate HIF1A-mediated immune escape were selected and examined for detailed functions. The expression of circ_0000977 could be induced by hypoxia, and circ_0000977 knockdown enhanced the killing effect of NK cells on PC cells under hypoxia through HIF1A and ADAM10. HIF1 and ADAM10 were direct downstream targets of miR-153; circ_0000977 served as a sponge for miR-153 to counteract miR-153-mediated repression of HIF1 and ADAM10 mRNA through direct targeting in both 293T cells and Panc-1 cells. miR-153 inhibition exerted an opposing effect on HIF1A-mediated immune escape of PC cells to circ_0000977 knockdown; the effect of circ_0000977 knockdown were partially attenuated by miR-153 inhibition. In summary, circ_0000977/miR-153 axis modulates HIF1A-mediated immune escape of PC cells through miR-153 downstream targets HIF1A and ADAM10. We provided a novel mechanism of HIF1A-mediated immune escape of PC cells from the perspective of circRNAs-miRNA-mRNA axis. Abbreviations: Pancreatic cancer (PC); peripheral blood lymphocytes (PBLs); A Disintegrin and Metalloproteinase Domain 10 (ADAM10); MHC class I-related molecule A (MICA); soluble MICA (sMICA); membrane MICA (mMICA); Hypoxia-inducible factor 1-alpha (HI1FA); long non-coding RNAs (lncRNAs); non-coding RNAs (ncRNAs); natural killer (NK); Haematoxylin and eosin (H&E); Immunohistochemistry (IHC); natural killer group 2 member D (NKG2D).

Long noncoding RNA FEZF1-AS1 predicts poor prognosis and modulates pancreatic cancer cell proliferation and invasion through miR-142/HIF-1α and miR-133a/EGFR upon hypoxia/normoxia.

Nowadays, pancreatic cancer (PC) remains the most lethal tumor, partially due to the invasive and treatment-resistant phenotype induced by the extent of hypoxic stress within the tumor tissue. According to previous studies, miR-142/HIF-1α and miR-133a/EGFR could modulate PC cell proliferation under hypoxic and normoxic conditions, respectively. In the present study, FEZF1-AS1, a recently described oncogenic long noncoding RNA, was predicted to target both miR-142 and miR-133a; thus, we hypothesized that FEZF1-AS1 might affect PC cell proliferation through these two axes under hypoxic or normoxic conditions. In PC cell lines, FEZF1-AS1 acted as an oncogene via promoting PC cell proliferation and invasion through miR-142/HIF-1α axis under hypoxic condition; however, FEZF1-AS1 failed to affect the protein levels of HIF-1α and VEGF under the normoxic condition, suggesting the existence of another signaling pathway under normoxic condition. As predicted by an online tool, FEZF1-AS1 could target miR-133a to inhibit its expression; under the normoxic condition, FEZF1-AS1 exerted its effect on PC cell lines through miR-133a/EGFR axis. Taken together, FEZF1-AS1 might be a promising target in controlling the aberrant proliferation and invasion of PC cell lines.

[Operative strategy and short-term efficacy of recurrent groin hernia].

OBJECTIVE: To explore the appropriate operative strategy in recurrent groin hernia repair. METHODS: Clinical and follow-up data of 82 patients with recurrent groin hernia undergoing operation at Department of Pancreatobiliary Surgery, Xiangya Hospital of Central South University from April 2010 to April 2017 were analyzed retrospectively. The operative approaches included laparoscopic transabdominal preperitoneal (TAPP) hernia repair, Lichtenstein repair and hybrid repair. Surgical method selection was based on the basis of European Hernia Society guidelines, combined with hernia histories, preoperative examination results and intra-operative results: (1) When an anterior approach (Lichtenstein, Bassini or Shouldice surgery) was adopted in the previous operation, TAPP was preferred for the recurrent groin hernia. (2) When the previous operation was an posterior approach [TAPP or total extraperitoneal hernioplasty (TEP)], Lichtenstein method was preferred. Moreover, Lichtenstein surgery with local anesthesia or nerve block was also selected when the patient could not tolerate general anesthesia. (3) When extensive preperitoneal adhesions were found in patients with previous anterior approach repair during laparoscopic exploration, especially in patients who had relapsed after multiple operations or had previous biochemical glues injection, hybrid surgery was preferred. RESULTS: All 82 patients completed operations smoothly. TAPP, Lichtenstein and hybrid operation were applied in 74, 4 and 4 patients, respectively, with median operative time of 70 minutes (40-130 minutes) in TAPP, 60 minutes (40-90 minutes) in Lichtenstein and 120 minutes (70-150 minutes) in hybrid operation, respectively. The median numerical rating scales (NRS) score was 2 (0-6) on postoperative day 1. The incidences of postoperative seroma, pain and urinary retention were 4.9% (4/82), 2.4% (2/82) and 1.2% (1/82) respectively. The median postoperative hospital stay was 2 days (1-6 days). Seventy-two patients were followed-up from 11 to 87 months. The median follow-up period was 27 months. The median inguinal pain questionnaire (IPQ) score was 2 (0-8) month after operation. One recurrent case was reported 1 year after operation. No incision or mesh infection and long-term inguinal chronic pain were observed. CONCLUSIONS: For recurrent patients with previous open anterior approach, TEP and TAPP repair are equivalent surgical techniques, and the choice should be tailored to the surgeon's expertise. For those with previous TAPP or TEP repair, Lichtenstein technique is recommended. For those with adhesions both in anterior transverse fascia and pre-peritoneum, hybrid operation may be the preferable choice according to adhesion conditions.

LncRNA BC032020 suppresses the survival of human pancreatic ductal adenocarcinoma cells by targeting ZNF451.

This study examined the effects of long non­coding RNA (lncRNA) BC032020 on the development of human pancreatic ductal adenocarcinoma (PDAC), and the potential molecular mechanisms responsible for these effects. The expression of BC032020 was assessed in 20 pairs of PDAC tumor tissues and adjacent normal tissues. The overexpression of BC032020 was enforced in the AsPC­1 and PANC­1 cells, and the effects on cell proliferation, cell cycle distribution, cell migration and apoptosis were determined. We also analyzed the functions of zinc finger protein 451 (ZNF451), which shares a gene sequence with two exons of BC032020 and a non­coding region with another two exons, in PDAC cells. The AsPC­1 and PANC­1 cells that overexpressed BC032020 were used to establish a subcutaneous tumor xenograft model in order to examine the effects of BC032020 on tumor growth in vivo. The results revealed that the BC032020 levels in the PDAC tumor tissues were lower than those in the adjacent normal tissues, and ZNF451 expression inversely correlated with the BC032020 levels in the PDAC tumor tissues and cell lines. BC032020 overexpression led to a decrease in ZNF451 expression; it also suppressed the proliferation and migration of the AsPC­1 and PANC­1 cells, and induced G1 phase arrest and cell apoptosis. The results of in vivo experiments revealed that BC032020 suppressed tumor growth in a xenograft model by inhibiting ZNF451 expression. Taken together, the findings of this study indicate that BC032020 suppresses the survival of PDAC cells by inhibiting ZNF451 expression.

Long Noncoding RNA TUG1/miR-29c Axis Affects Cell Proliferation, Invasion, and Migration in Human Pancreatic Cancer.

Given the low resection rate and chemoresistance of patients with pancreatic cancer (PC), their survival rates are typically poor. Long noncoding RNAs (lncRNAs) have recently been shown to play an important role in tumourigenesis and human cancer progression, including in PC. In this study, we aimed to investigate the role of taurine-upregulated gene 1 (TUG1) in PC. A quantitative polymerase chain reaction was used to analyse TUG1 expression in PC tissues and peritumoural normal tissues. TUG1 was overexpressed in PC tissues compared with that in peritumoural normal tissues, and the high expression of TUG1 was associated with the poor prognosis of patients with PC. Furthermore, TUG1 knockdown significantly inhibited the proliferation and invasion of PC cells both in vitro and in vivo, while overexpression TUG1 promoted tumour cell proliferation, migration, and invasion. TUG1 directly targeted miR-29c, a tumour suppressor in several cancers. TUG1 knockdown significantly increased the expression of miR-29c and subsequently induced the downregulation of integrin subunit beta 1 (ITGB1), matrix metalloproteinase-2 (MMP2), and matrix metalloproteinase-9 (MMP9). The downregulation of miR-29c abolished the TUG1 knockdown-mediated inhibition of tumour growth in vitro and in vivo, whereas the upregulation of miR-29c enhanced the effects of TUG1 knockdown on PC cells. In conclusion, we demonstrate for the first time the oncogenic role of TUG1 in PC. The downregulation of TUG1 significantly inhibited the growth and migratory ability of PC cells in vitro and in vivo by targeting miR-29c. Our study provides a novel potential diagnostic biomarker and therapeutic target for PC.

MicroRNA-613 inhibits the progression of gastric cancer by targeting CDK9.

MicroRNAs (miRNAs) play an important role in the development and progression of human malignancy. miR-613, as a tumour suppressor, was reported to decrease in several tumours. However, the expression levels and role of miR-613 in gastric cancer remain unknown. In this study, we found that miR-613 was evidently downregulated in gastric cancer tissue and cell. The functional analysis showed that miR-613 suppressed cell proliferation and migration in gastric cancer. Next, the dual-luciferase reporter system supported CDK9 as a direct target gene of miR-613. miR-613 mimics evidently repressed CDK9 expression in gastric cancer cells. Furthermore, we found that CDK9 in upregulated in gastric cancer and the CDK9 expression levels were inversely correlated with that of miR-613 in gastric cancer tissues. Overall, the results revealed that miR-613, as a tumour suppressor, involves in gastric cancer progression and metastasis by targeting CDK9, implying a novel potential therapeutic target for the treatment of gastric cancer.

Long noncoding RNA NNT-AS1 promotes hepatocellular carcinoma progression and metastasis through miR-363/CDK6 axis.

Long non-coding RNAs (lncRNAs) have been tested to act as important regulator in liver cancer genesis and progression. LncRNA Nicotinamide Nucleotide Transhydrogenase-antisense RNA1 (NNT-AS1) has been reported to participate in the tumorigenesis. However, the exact molecular mechanism of NNT-AS1 in hepatocellular carcinoma (HCC) is still unknown. In present study, our team identified the up-regulated expression of NNT-AS1 in HCC tissue and cell lines compared with adjacent noncancerous tissue and normal cells. Moreover, HCC patients with high NNT-AS1 levels had poor prognosis than that with low NNT-AS1 level (p=0.0089). In vitro, gain- and loss-of-function experiments revealed that enhanced NNT-AS1 expression promoted the proliferation ability and alleviated the cycle arrest and apoptosis, while NNT-AS1 knockdown suppressed the proliferation and induced G0/G1 phase arrest and apoptosis. In vivo, NNT-AS1 knockdown inhibited the HCC neoplastic tumor volume and weight. Bioinformatics analysis and luciferase reporter assay validated that miR-363 targeted NNT-AS1 and CDK6 3'-UTR. MiR-363 was down-regulated in HCC tissue and cells. NNT-AS1 competed with CDK6 for miR-363 binding and could increase CDK6 expression. In summary, our results suggest the oncogenic role of NNT-AS1 in HCC tumorigenesis through miR-363/CDK6 axis, providing a novel therapeutic target for human HCC.

Downregulation of ULK1 by microRNA-372 inhibits the survival of human pancreatic adenocarcinoma cells.

Dysregulation of microRNA (miRNA) expression in various cancers and their role in cancer progression is well documented. The purpose of this study was to investigate the biological role of miR-372 in human pancreatic adenocarcinoma (HPAC). We collected 20 pairs of HPAC tissues and adjacent non-cancerous tissues to detect miR-372 expression levels. We transfected BXPC-3 and PANC-1 cells with miR-372 inhibitor/mimics to study their effect on cell proliferation, apoptosis, invasion, migration and autophagy. In addition, miR-372 mimics and a tumor protein UNC51-like kinase 1 (ULK1) siRNA were co-transfected into BXPC-3 and PANC-1 cells to explore the mechanism of miR-372 and ULK1 on HPAC tumorigenesis. We found that the expression of miR-372 was markedly downregulated in HPAC cells compared to adjacent normal tissues. Furthermore, functional assays showed that miR-372 inhibited cell proliferation, invasion, migration and autophagy in BXPC-3 and PANC-1 cells. An inverse correlation between miR-372 expression and ULK1 expression was observed in HPAC tissues. Downregulation of ULK1 inhibited the overexpression effects of miR-372, and upregulation of ULK1 reversed the effects of overexpressed miR-372. Finally, we found that silencing ULK1 or inhibiting autophagy partly rescued the effects of miR-372 knockdown in HPAC cells, which may explain the influence of miR-372/ULK1 in HPAC development. Taken together, these results revealed a significant role of the miR-372/ULK1 axis in suppressing HPAC cell proliferation, migration, invasion and autophagy.

LncRNA XIST Promotes Pancreatic Cancer Proliferation Through miR-133a/EGFR.

According to recent studies, long non-coding RNA X-inactive specific transcript (XIST) is involved in the development and progression of many malignant tumors including pancreatic cancer. We validated the detailed role of XIST in human pancreatic cancer (PC) cell lines and PC tissues so as to determine its exact function and the mechanism by which it affected PC proliferation. In our research, lncRNA-XIST was specifically upregulated in PC tissues and cell lines, and high XIST expression in PC was related to poorer prognosis (larger tumor size, perineural invasion, lymph node micrometastases, and shorter overall survival). XIST augmented PC cell proliferation. Recently, the interaction between lncRNA and miRNA has been frequently reported to play major role in several biological processes. In the present study, XIST and miR-133a reciprocally inhibited each other in PC cells. Exogenous miR-133a expression significantly inhibited PC cell proliferation. Moreover, as exhibited by luciferase reporter gene assays, miR-133a bound to XIST and the 3'UTR of EGFR by direct targeting. In PC tissues, miR-133a expression was down-regulated and EGFR expression was up-regulated; miR-133a was inversely correlated with EGFR and XIST, respectively; XIST was positively correlated with EGFR. Taken together, these findings will shed light on the role and mechanism of XIST/miR-133a/EGFR in regulating PC cells proliferation. XIST may serve as a potential therapeutic target in PC in the future. J. Cell. Biochem. 118: 3349-3358, 2017. © 2017 Wiley Periodicals, Inc.

MiR-142 modulates human pancreatic cancer proliferation and invasion by targeting hypoxia-inducible factor 1 (HIF-1α) in the tumor microenvironments.

MicroRNAs regulate most protein-coding genes, including genes important in cancer and other diseases. In this study, we demonstrated that the expression of miR-142 could be significantly suppressed in pancreatic cancer specimens and cell lines compared to their adjacent tissues and normal pancreatic cells. Growth and invasion of PANC-1 and SW1990 cells were attenuated by overexpression of miR-142 in vitro With the help of bioinformatics analysis, hypoxia-inducible factor 1 (HIF-1α) was identified to be a direct target of miR-142, and a luciferase reporter experiment confirmed this discovery. Overexpression of miR-142 decreases protein expression of HIF-1α. In the hypoxic microenvironment, HIF-1α was up-regulated while miR-142 was down-regulated. The invaded cells significantly increased in the hypoxic microenvironment compared to the normoxic microenvironment. The hypoxia treatment induced cells' proliferation, and invasion could be inhibited by miR-142 overexpression or HIF-1α inhibition. Moreover, expression of epithelial-mesenchymal transition (EMT) markers, Vimentin, VEGF-C and E-cad, was altered under hypoxia conditions and regulated by miR-142/HIF-1α. Above all, these findings provided insights on the functional mechanism of miR-142, suggesting that the miR-142/HIF-1α axis may interfere with the proliferative and invasive properties of pancreatic cancer cells, and indicated that miR-142 could be a potential therapeutic target for pancreatic cancer.