Minghua Hu

Increased level of H19 long noncoding RNA promotes invasion, angiogenesis, and stemness of glioblastoma cells

OBJECT Increased levels of H19 long noncoding RNA (lncRNA) have been observed in many cancers, suggesting that overexpression of H19 may be important in the development of carcinogenesis. However, the role of H19 in human glioblastoma is still unclear. The object of this study was to examine the level of H19 in glioblastoma samples and investigate the role of H19 in glioblastoma carcinogenesis. METHODS Glioblastoma and nontumor brain tissue specimens were obtained from tissue obtained during tumor resection in 30 patients with glioblastoma. The level of H19 lncRNA was detected by real-time quantitative reverse transcription polymerase chain reaction. The role of H19 in invasion, angiogenesis, and stemness of glioblastoma cells was then investigated using commercially produced cell lines (U87 and U373). The effects of H19 overexpression on glioblastoma cell invasion and angiogenesis were detected by in vitro Matrigel invasion and endothelial tube formation assay. The effects of H19 on glioblastoma cell stemness and tumorigenicity were investigated by neurosphere formation and an in vivo murine xenograft model. RESULTS The authors found that H19 is significantly overexpressed in glioblastoma tissues, and the level of expression was associated with patient survival. In the subsequent investigations, the authors found that overexpression of H19 promotes glioblastoma cell invasion and angiogenesis in vitro. Interestingly, H19 was also significantly overexpressed in CD133(+) glioblastoma cells, and overexpression of H19 was associated with increased neurosphere formation of glioblastoma cells. Finally, stable overexpression of H19 was associated with increased tumor growth in the murine xenograft model. CONCLUSIONS The results of this study suggest that increased expression of H19 lncRNA promotes invasion, angiogenesis, stemness, and tumorigenicity of glioblastoma cells. Taken together, these findings indicate that H19 plays an important role in tumorigenicity and stemness of glioblastoma and thus could be a therapeutic target for treatment of glioblastoma in the future.

MiR-218 sensitizes glioma cells to apoptosis and inhibits tumorigenicity by regulating ECOP-mediated suppression of NF-κB activity

INTRODUCTION Malignant gliomas are the most common and deadly primary brain tumors in adults. Increasing evidence has indicated that microRNAs (miRNAs) have an influence on the regulation of apoptotic cell signaling. Downregulation of miRNA 218 (miR-218) has been indicated in human glioma specimens. Here, we investigate the function of miR-218 in apoptosis and tumor growth of glioma cells. METHODS The expression of miR-218 was detected by real-time quantitative reverse transcriptase PCR. The effects of miR-218 on glioma cell proliferation and tumorigenicity were investigated by in vitro clonogenicity and in vivo xenograft assay. Apoptosis was evaluated by flow cytometric analysis and assay by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling. The downstream targets of miR-218 were identified by bioinformatics analysis and further validated by Western blot and luciferase reporter assay. RESULTS Overexpression of miR-218 induces glioma cell apoptosis and inhibits glioma cell viability, proliferation, and tumorigenicity. Epidermal growth factor receptor-coamplified and overexpressed protein (ECOP) was identified as a functional downstream target of miR-218, which can regulate transcriptional activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and associated with apoptotic response. Ectopic expression of ECOP rescued the glioma cells from miR-218-induced apoptosis and increased NF-κB activity. CONCLUSION These results suggest that miR-218 sensitizes glioma cells to apoptosis by regulating ECOP-mediated suppression of NF-κB activity, which may provide novel opportunities for glioma therapy.

Over-expression of regulator of G protein signaling 5 promotes tumor metastasis by inducing epithelial–mesenchymal transition in hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is the second leading cause of cancer‐related deaths worldwide. The regulator of G‐protein signaling 5 (RGS5) has been reported to be highly expressed in some malignant tumors. However, its expression and role in HCC has not been reported.

MicroRNA-126 inhibits tumor proliferation and angiogenesis of hepatocellular carcinoma by down-regulating EGFL7 expression

This study aims to explore the effects of microRNA-126 (miR-126) on tumor proliferation and angiogenesis of hepatocellular carcinoma (HCC) by targeting EGFL7. HCC tissues and adjacent normal tissues were obtained from 71 HCC patients. Immunohistochemistry (IHC) was conducted to detect expressions of EGFL7 and VEGF and the micro-vessel density (MVD). HCC cell lines were collected and assigned into the blank, miR-126 mimics, miR-126 inhibitors, miR-126 mimics negative control (NC), miR-126 inhibitors NC, si-EGFL7, and miR-126 inhibitors + si-EGFL7 groups. Expressions of miR-126 and EGFL7 mRNA were detected by qRT-PCR assay. The protein expressions of EGFL7 and VEGF were measured by Western blotting. MTT assay was used to measure the proliferation of HCC cells. Tumor xenograft model in nude mice was utilized to evaluate the influence of miR-126 on tumor growth. HCC tissues had higher miR-126 expression and lower EGFL7 mRNA expression than adjacent normal tissues. Compared with the blank, miR-126 mimic NC, miR-126 inhibitor NC and miR-126 inhibitors + si-EGFL7 groups, the protein expressions of EGFL7 and VEGF and cell proliferation were reduced in the miR-126 mimics and si-EGFL7 groups, while the opposite trend was found in the miR-126 inhibitors group. Compared with the blank and miR-126 inhibitors + siRNA-EGFL7 groups, tumor size, tumor weight, and MVD of transplanted tumors in nude mice were significantly reduced in the miR-126 mimics and siRNA-EGFL7 groups, while the opposite trend was found in the miR-126 inhibitors group. In conclusion, miR-126 could inhibit tumor proliferation and angiogenesis of HCC by down-regulating EGFL7 expression.

The Role of MicroRNA in Tumor Invasion and Metastasis

Invasion and metastasis are the hallmarks of malignant tumors differing from benign diseases. Most of cancer deaths are mainly due to the development of tumor metastasis rather than primary lesions. Therefore, understanding the molecular mechanisms of invasion and metastasis that take place in malignant cells will provide insight into the development of new therapeutic approaches. However, the complex processes of tumor invasion and metastasis pose a great difficulty in studying their molecular bases. Recent studies have shown that a class of endogenous small nonprotein coding RNAs, termed microRNAs (miRNAs), play an important role in invasion and metastasis of several malignancies, such as breast, liver, prostate and colorectal cancers. In this review, we will summarize the recent studies on the miRNAs in tumor invasion and metastasis, and accentuate the role of miRNAs in elucidating molecular mechanisms of these important processes.

MicroRNA-9 modified bone marrow-derived mesenchymal stem cells (BMSCs) repair severe acute pancreatitis (SAP) via inducing angiogenesis in rats

BackgroundSevere acute pancreatitis (SAP) is an acute abdominal disease characterized by pancreatic necrosis and systemic disease. In a previous study, we showed that bone marrow-derived mesenchymal stem cells (BMSCs) can reduce SAP by secreting microRNA (miR)-9; however, the underlying mechanism remains unclear. The present study investigated the mechanism underlying BMSC-induced pancreatic regeneration.MethodsBMSCs were isolated, and miR-9 modified/antagonized BMSCs (pri-miR-9-BMSCs/TuD-BMSCs) were generated and injected into SAP rats. The levels of inflammatory cytokines and histopathologic changes were examined using ELISA and H&E staining. Angiogenesis was analyzed by qRT-PCR, western blotting, and immunohistochemistry. Cell function tests, dual luciferase reporter assays, cell co-culture, western blotting, and cell tracing were used to explore the mechanisms underlying miR-9 induced angiogenesis.ResultsPri-miR-9-BMSCs induced angiogenesis in SAP rats (Ang-1↑, TIE-2↑, and CD31↑) and repaired damaged vascular endothelial cells (VECs) in vitro, promoting angiogenesis (Ang-1↑, TIE-2↑, PI3K↑, AKT↑, p-AKT↑, CD31↑, and CD34↑). Pri-miR-9-BMSCs released miR-9 into VECs or injured pancreatic tissue, targeting the VE-cadherin gene and promoting PI3K/AKT signaling to treat SAP (VE-cadherin↓, β-catenin↓, PI3K↑, p-AKT↑), whereas antagonizing miR-9 in BMSCs did not alleviate or aggravated SAP.ConclusionsPri-miR-9-BMSCs can repair injured pancreatic tissue by secreting miR-9 and promoting angiogenesis.

Inferoposterior duodenal approach for laparoscopic pancreaticoduodenectomy

AIM To investigate the advantages of inferoposterior duodenal approach (IPDA) for laparoscopic pancreaticoduodenectomy (LPD). METHODS A total of 36 patients subjected to LPD were admitted to the Affiliated Yijishan Hospital of Wannan Medical College from December 2009 to February 2015. These patients were diagnosed with an ampullary tumour or a pancreatic head tumour through computed tomography, magnetic resonance imaging or endoscopic retrograde cholangiopancreatography preoperatively. The cases were selected on the basis of the following criteria: tumour diameter < 4 cm; no signs of peripheral vascular invasion; evident lymph node swelling; and distant metastasis. Of the 36 cases, 20 were subjected to anterior approach (AA; AA group) and 16 were subjected to IPDA (IPDA group). Specimen removal time, intraoperative blood loss and postoperative complications in the two groups were observed, and their differences were compared. RESULTS During the operation, 2 cases in the AA group and 2 cases in the IPDA group were converted to laparotomy; these cases were excluded from statistical analysis. The remaining 32 cases successfully completed the surgery. The AA group and IPDA group exhibited the specimen removal time of 205 ± 52 and 160 ± 35 min, respectively, and the difference was significant (P < 0.01). The AA group and IPDA group revealed the intraoperative blood loss of 360 ± 210 mL and 310 ± 180 mL, respectively, but these values were not significantly different. Postoperative pathological results revealed 4 cases of inferior common bile duct cancer, 8 cases of duodenal papillary cancer, 6 cases of ampullary cancer, 13 cases of pancreatic cancer, 3 cases of chronic pancreatitis accompanied with cyst formation or duct expansion, and 2 cases of mucinous cystic tumour in the pancreatic head. The postoperative complications were pulmonary Staphylococcus aureus infection, incision faulty union, ascites induced poor drainage accompanied with infection, bile leakage, pancreatic leakage and delayed abdominal bleeding. CONCLUSION In IPDA, probing for important steps can be performed in early stages, surgical procedures can be optimised and operation time can be shortened.