Effects of laparoscopic sleeve gastrectomy on serum lncRNA levels in obese patients

Obesity is a disease associated with excessive fat accumulation in the body, which body mass index (BMI) is greater than 30 kg/m. Bariatric surgery technique is one of the most common treatment options for obesity with the advantage of faster weight loss in a short time. lncRNAs play a role in adipogenesis and metabolic diseases, including obesity, type 2 diabetes, cardiovascular disease (CVD), osteoarthritis, and hypertension, so they are significant targets for therapeutic options. In this study, we aimed to determine lncRNAs and specific parameters that show different expressions in the plasma of patients with obesity. We included fifteen patients with BMI greater than 30 kg/m2 before and less than 30 kg/m2 after laparoscopic sleeve gastrectomy (LSG) in the study. Total RNAs, including lncRNAs and other non-coding RNAs, were isolated from plasma samples of patients, and eight lncRNAs (H19, Neat1, HOTAIR, ANRIL,  MALAT1, ATB, SNGH5, UCA1) were quantified by real-time PCR. Gene Ontology, KEGG, and relation of obesity analysis were utilized. Unpaired Student's t-test Pearson correlation analysis was used for statistical analysis. We observed a statistically significant increase in the expression levels of all lncRNAs in the patients with the post-operative BMI change. We have added a new dimension to the biomarker studies related to obesity and the clinical follow-up of patients undergoing LSG surgery. Further studies are required for enlighting the molecular mechanisms

Tumour suppressor PTEN enhanced enzyme activity of GPx, SOD and catalase by suppression of PI3K/AKT pathway in non-small cell lung cancer cell lines

Phosphates and tensin homologue deleted on chromosome 10 (PTEN) is a tumour suppressor gene which dephosphorilates phosphoinositol 3,4,5 triphosphates. Therefore PTEN can regulate PI3K/AKT pathway in cells. Because of promoter methylation or gene deletion, PTEN expression is commonly decreased or lost in non-small cell lung cancer (NSCLC) cell lines. Therefore, we hypothesized that PTEN could regulate the activity of superoxide dismutase (CuZnSOD), glutathione peroxidase (GPx) and catalase. We first recreated PTENwt, G129R and G129E expressions in lung cell lines, in which endogenous PTEN expression was not detected. Then, we showed that PTEN could suppress AKT activity by its lipid phosphatase domain. We then examined the effect of recreated PTEN expressions in NSCLC cells. While PTENwt expression caused enhanced activity of SOD, GPx and catalase in transfected cells lines, neither G129R nor G129E expression effected enzyme activities. These results suggest that PTEN can up-regulate SOD, GPx and catalase activity by inhibition of PI3K/AKT pathway in NSCLC cell lines. © 2013 Informa UK, Ltd

Regulation

Background: Small Cell Lung Cancer (SCLC) is a highly aggressive malignancy. MYC family oncogenes are amplified and overexpressed in 20% of SCLCs, showing that MYC oncogenes and MYC regulated genes are strong candidates as therapeutic targets for SCLC. c-MYC plays a fundamental role in cancer stem cell properties and malignant transformation. Several targets have been identified by the activation/repression of MYC. Deregulated expression levels of lncRNAs have also been observed in many cancers.Objective: The aim of the present study is to investigate the lncRNA profiles which depend on MYC expression levels in SCLC.Methods: Firstly, we constructed lentiviral vectors for MYC overexpression/inhibition. MYC expression is suppressed by lentiviral shRNA vector in MYC amplified H82 and N417 cells, and overexpressed by lentiviral inducible overexpression vector in MYC non-amplified H345 cells. LncRNA cDNA is transcribed from total RNA samples, and 91 lncRNAs are evaluated by qRT-PCR.Results: We observed that N417, H82 and H345 cells require MYC for their growth. Besides, MYC is not only found to regulate the expressions of genes related to invasion, stem cell properties, apoptosis and cell cycle (p21, Bcl2, cyclinD1, Sox2, Aldh1a1, and N-Cadherin), but also found to regulate lncRNAs. With this respect, expressions of AK23948, ANRIL, E2F4AS, GAS5, MEG3, H19, L1PA16, SFMBT2, ZEB2NAT, HOTAIR, Sox2OT, PVT1, and BC200 were observed to be in parallel with MYC expression, whereas expressions of Malat1, PTENP1, Neat1, UCA1, SNHG3, and SNHG6 were inversely correlated.Conclusion: Targeting MYC-regulated genes as a therapeutic strategy can be important for SCLC therapy. This study indicated the importance of identifying MYC-regulated lncRNAs and that these can be utilized to develop a therapeutic strategy for SCLC.C1 [Tokgun, Onur; Tokgun, Pervin E.; Akca, Hakan] Pamukkale Univ, Fac Med, Dept Med Genet, POB 20070, Denizli, Turkey.[Tokgun, Onur; Inci, Kubilay; Akca, Hakan] Pamukkale Univ, Inst Med Sci, Dept Canc Mol Biol, Denizli, Turkey

Design of a Lentiviral Vector for the Inducible Expression of MYC: A New Strategy for Construction Approach.

Lentiviral vectors are powerful tools for gene expression studies. Here we report the construction of pTIJ, a vector for inducible gene expression. pTIJ was generated from pTRIPZ backbone, which is designed for the inducible expression of shRNA sequences, by the introducing of a multiple cloning site upstream of the Tet promoter and the removal of miR30 flanking sequences. To evaluate pTIJ as a tool for the inducible expression of genes of interest, we introduced MYC cDNA into pTIJ and infected two small cell lung cancer cell lines, H209 and H345. Induction of MYC expression by doxycycline was detectable in both cell lines by real-time PCR and western blot analysis. This study highlights the relevance of pTIJ vector to allow the inducible expression of any gene of interest. In our belief, pTIJ will be an extremely useful tool to simplify the generation of genetically engineered cell lines for the inducible expression of cDNA sequences in biological studies. Furthermore, we report the generation of a pTIJ-MYC vector for the inducible expression of the oncogene MYC

MYC-driven regulation of long non-coding RNA profiles in breast cancer cells.

AIM: MYC deregulation contributes to breast cancer development and progression. Deregulated expression levels of long non-coding RNAs (lncRNA) have been demonstrated to be critical players in development and/or maintenance of breast cancer. In this study we aimed to evaluate lncRNA expressions depending on MYC overexpression and knockdown in breast cancer cells. MATERIALS AND METHODS: Cells were infected with lentiviral vectors by either knockdown or overexpression of c-MYC. LncRNA cDNA was transcribed from total RNA samples and lncRNAs were evaluated by qRT-PCR. RESULTS: Our results indicated that some of the lncRNAs having tumor suppressor (GAS5, MEG3, lincRNA-p21) and oncogenic roles (HOTAIR) are regulated by c-MYC. CONCLUSION: We observed that c-MYC regulates lncRNAs that have important roles on proliferation, cell cycle and etc. Further studies will give us a light to identify molecular mechanisms related to MYC-lncRNA regulatory pathways in breast cancer