LncRNA-ANRIL inhibits cell senescence of vascular smooth muscle cells by regulating miR-181a/Sirt1.

BACKGROUND: Cardiovascular disease is one of the major threats to human life and health, and vascular aging is an important cause of its occurrence. Antisense non-coding RNA in the INK4 locus (ANRIL) is a kind of long non-coding RNA (lncRNA) that plays important roles in cell senescence. However, the role and mechanism of ANRIL in senescence of vascular smooth muscle cells (VSMCs) are unclear. METHODS: Cell viability and cell cycle were evaluated using an MTT assay and flow cytometry analysis, respectively. Senescence-associated (SA)-ß-galactosidase (gal) staining was used to determine cell senescence. Dual luciferase reporter assays were conducted to confirm the binding of ANRIL and miR-181a, as well as miR-181a and Sirt1. The expression of ANRIL, miR-181a, and Sirt1 was determined using qRT-PCR and protein levels of SA-ß-gal and p53-p21 pathway-related proteins were evaluated by Western blotting. RESULTS: ANRIL and Sirt1 were down-regulated, whereas miR-181a was up-regulated in aging VSMCs. In young and aging VSMCs, over-expression of ANRIL could down-regulate miR-181a and up-regulate Sirt1. MTT and SA-ß-gal staining assays showed that over-expression of ANRIL and inhibition of miR-181a promoted cell viability and inhibited VSMC senescence. The dual-luciferase reporter assay determined that miR-181a directly targets ANRIL and the 3'-UTR of Sirt1. Furthermore, over-expression of ANRIL inhibited cell cycle arrest and the p53-p21 pathway. CONCLUSION: ANRIL promotes cell viability and inhibits senescence in VSMCs, possibly by regulating miR-181a/Sirt1, and alleviating cell cycle arrest by inhibiting the p53-p21 pathway. This study provides novel insights for the role of ANRIL in the development of cell senescence.

Construction of a novel vector expressing Survivin-shRNA and fusion suicide gene yCDglyTK and its application in inhibiting proliferation and migration of colon cancer cells.

Despite progress achieved in cancer chemotherapy in recent decades, adverse effects remain a limiting factor for a number of patients with colorectal cancer, suggesting the requirement for novel therapeutic strategies. Gene therapy appears to be a promising strategy for treating cancer. The present study aimed to investigate the anti-tumor effect of a combined gene therapy, using Survivin downregulation by RNAi and a fusion suicide gene yCDglyTK therapy system. A triple-gene vector expressing Survivin-targeted small hairpin RNA (Survivin-shRNA) and fusion suicide gene yCDglyTK was constructed, and administered to HCT116 cells. Survivin expression decreased significantly and yCDglyTK fusion gene expression was confirmed by both reverse transcription-quantitative polymerase chain reaction and western blot analysis. Introduction of Survivin-shRNA into yCDglyTK/prodrug system eradicated colon cancer cells and induced apoptosis more effectively. Furthermore, this therapeutic system is able to inhibit the migration of HCT116 cells. These results indicate that the recombinant plasmid may serve as a novel gene therapy approach to treat colorectal carcinoma.

The Clinical Significance of miR-34a in Pancreatic Ductal Carcinoma and Associated Molecular and Cellular Mechanisms.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) exhibits poor prognosis and resistance to chemotherapy. This study was to identify the biomarkers associated with the progression, poor prognosis and chemoresistance of PDAC. METHODS: miR-34a and miR-150 levels in the plasma and tissues from PDAC patients were measured by real-time PCR. Xenograft PDAC tumor models were established in mice by inoculation of CD133+ stem cells isolated from PDAC tumors. Protein expression was measured by Western blot. RESULTS: The plasma miR-34a and miR-150 levels were significantly lower in PDAC patients than in patients with benign pancreatic lesions and in healthy subjects. The miR-34a and miR-150 levels in the tumor tissues were significantly lower than in pancreatic tissues with benign lesions. The protein levels of CD133, Notch1, Notch2 and Notch4 receptors in PDAC tumor tissues were significantly higher than in pancreatic tissues with benign lesions. miR-34a injection significantly inhibited the tumor growth of PDAC tumors and sensitized the anticancer effects of 5-fluorouracil (5-FU). miR-34a significantly inhibited Notch1, Notch2 and Notch4 expression in xenograft tumor tissues in vivo and BxPC-3 cells in vitro. miR-34a and miR-150 significantly induced apoptosis and inhibited proliferation, invasion and migration in BxPC-3 cells. miR-34a, but not miR-150, significantly sensitized the anticancer effect of 5-FU in BxPC-3 cells in vitro. CONCLUSION: A loss of expression of miR-34a, but not of miR-150, is associated with disease progression and poor prognosis in PDAC patients, and may be involved in the chemoresistance of PDAC cells.

microRNA-214 functions as a tumor suppressor in human colon cancer via the suppression of ADP-ribosylation factor-like protein 2.

microRNAs (miRNAs/miRs) are a conserved class of endogenous, short non-coding RNAs that post-transcriptionally regulate the expression of genes involved in diverse cellular processes. miR-214 has been reported to be associated with several cancers, including human colon cancer. However, the function of miR-214 in colon cancer development is poorly understood. In the current study, miR-214 was demonstrated to be downregulated in colon cancer tissues compared with healthy colon tissues. Functional studies showed that miR-214 overexpression results in the inhibition of cell viability, colony formation and proliferation, and the induction of cell apoptosis. ADP-ribosylation factor-like protein 2 (ARL2) is predicted to be a target candidate of miR-214. A luciferase reporter assay, western blot analysis and quantitative polymerase chain reaction were performed, which revealed that miR-214 negatively regulates ARL2 expression by targeting its 3' untranslated region directly. In conclusion, the results of the present study revealed that miR-214 suppresses colon cancer cell growth via the suppression of ARL2, and indicated that miR-214 may present a significant potential therapeutic target for colon cancer.

[A comparison of efficacy and safety in the treatment of hyperglycemia with continuous subcutaneous insulin with insulin pump or multiple insulin injections daily in critical elderly patients].

OBJECTIVE: To compare efficacy and safety in the treatment of hyperglycemia with continuous subcutaneous insulin infusion (CSII) or multiple daily insulin injection (MDI) in critical elderly patients. METHODS: Ninety-four elderly patients in critical condition with fasting glucose (10.3+/-2.5) mmol/L were randomly divided into CSII group (46 cases) and MDI group (48 cases). Soluble human insulin was used in both groups, and the treatment lasted for 7 days, and blood glucose level, average insulin dosage, percentage of hypoglycemia during 7 days, blood C-reacting protein (CRP), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) level and acute physiology and chronic health evaluation II (APACHE II) scores on the 7th day, and mortality during 28 days were observed. RESULTS: Compared with MDI group, blood glucose was better controlled [76.1% (35/46) vs. 33.3% (16/48)], percentage of fair control of blood glucose level was higher [21.7% (10/46) vs. 14.6% (7/48)], percentage of poor control of blood glucose level was lower [2.2% (1/46) vs. 52.1% (25/48)], percentage of hypoglycemia was lower [10.9% (5/46) vs. 22.9% (11/48)], average insulin dosage during 7 days was less [(40.1+/-6.3) U/d vs. (46.2+/-7.1) U/d], serum TNF-alpha level [(11.5+/-2.7) microg/L vs. (19.8+/-4.2) microg/L], IL-6 level [(78.3+/-5.1)microg/L vs.(141.4+/-6.2) microg/L] and CRP level [(53.1+/-3.3) mg/L vs. (72.1+/-4.0) mg/L] on the 7th day was lower, APACHE II score was lower on the 7th day [(6.0+/-1.4) scores vs. (11.6+/-1.0) scores], and 28-day mortality was lower in CSII group [4.3% (2/46) vs. 16.7% (8/48)]. All the above values showed statistically significant difference between two groups (all P < 0.05). CONCLUSION: CSII can better control blood glucose and alleviate inflammatory response and improve prognosis in elderly critically ill patients.