Altererythrobacter amylolyticus sp. nov., isolated from lake sediment.

An aerobic, motile, Gram-stain-negative bacterium, designated strain NS1T, was isolated from interfacial sediment from Taihu Lake, China. The strain formed yellow colonies on R2A medium. Cells were ovoid to rod-shaped and non-spore-forming. Growth occurred at 15-40 °C (optimum, 28 °C), at pH 5.0-10.5 (optimum, 6.5-7.5) and in the presence of 0-1 % (w/v) NaCl (optimum, 0 %). Phylogenetic trees based on 16S rRNA gene sequences showed that strain NS1T represented a member of the genus Altererythrobacter and had the highest sequence similarity to Altererythrobacter troitsensis CCTCC AB 2015180T (97.1 %). The average nucleotide identity value between strain NS1T and the closest related strain based on their genomes was 78.6 %. The predominant ubiquinone was Q-10. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, an unidentified phospholipid, an unidentified glycolipid and six unidentified lipids. The genomic DNA G+C content was 66.6 mol%. On the basis of phenotypic and genotypic characteristics, strain NS1T represents a novel species of the genus Altererythrobacter, for which the name Altererythrobacter amylolyticus sp. nov. is proposed. The type strain is NS1T (=CGMCC 1.13679T=NBRC 113553T).

Adenovirus-mediated siRNA targeting c-Met inhibits proliferation and invasion of small-cell lung cancer (SCLC) cells.

BACKGROUND: The hepatocyte growth factor receptor c-Met and its ligand hepatocyte growth factor (HGF) have been reported to be involved in cellular motility, growth, and invasion by activating mitogenic signaling pathways. The overexpression of c-Met gene has been found in many malignant cancers, but the roles of c-Met overexpression in SCLC tumors still remain unclear. The aim of the present study was to explore its roles and potential as a therapeutic target for SCLC. METHODS: Quantitative real-time RT-PCR and immunohistochemistry assays were performed to detect the expression of c-Met mRNA and protein in SCLC tissue or corresponding non-tumor lung tissue samples. Adenovirus-mediated small interfering RNA (siRNA) was employed to down-regulate the expression of c-Met gene in SCLC cell line (NCI-H446). MTT and colony formation assays were performed to detect in vitro proliferation of NCI-H446 cells. In vitro wound-healing and transwell invasion assays were performed to detect in vitro invasion and metastasis of NCI-H446 cells. Finally, in vivo tumorigenicity and metastasis assays were done to analyze in vivo proliferation and metastasis of NCI-H446 cells in a xenograft model. RESULTS: We showed that the levels of c-Met mRNA expression were significantly higher in SCLC tissue samples (0.97±0.08) than those in corresponding non-tumor lung tissue samples (0.21±0.02; P<0.05). Additionally, the immunostaining of c-Met protein in SCLC tissues was stronger than that in corresponding non-tumor tissues. Adenovirus-mediated siRNA targeting c-Met could significantly down-regulate c-Met expression, and the specific down-regulation of c-Met expression in SCLC cells could strongly inhibit proliferation of SCLC cells both in vitro and in vivo. Moreover, c-Met down-regulation could also reduce invasion capacity in vitro and metastasis capacity in vivo of SCLC cells. CONCLUSIONS: Taken together, our results indicated that the overexpression of c-Met gene played an important role in the progression and development of SCLC, and adenovirus-mediated siRNA targeting c-Met could potentially be an experimental approach for SCLC gene therapy.

The pseudogene DUXAP10 promotes an aggressive phenotype through binding with LSD1 and repressing LATS2 and RRAD in non small cell lung cancer.

Pseudogenes have been considered as non-functional transcriptional relics of human genomic for long time. However, recent studies revealed that they play a plethora of roles in diverse physiological and pathological processes, especially in cancer, and many pseudogenes are transcribed into long noncoding RNAs and emerging as a novel class of lncRNAs. However, the biological roles and underlying mechanism of pseudogenes in the pathogenesis of non small cell lung cancer are still incompletely elucidated. This study identifies a putative oncogenic pseudogene DUXAP10 in NSCLC, which is located in 14q11.2 and 2398 nt in length. Firstly, we found that DUXAP10 was significantly up-regulated in 93 human NSCLC tissues and cell lines, and increased DUXAP10 was associated with patients poorer prognosis and short survival time. Furthermore, the loss and gain of functional studies including growth curves, migration, invasion assays and in vivo studies verify the oncogenic roles of DUXAP10 in NSCLC. Finally, the mechanistic experiments indicate that DUXAP10 could interact with Histone demethylase Lysine specific demethylase1 (LSD1) and repress tumor suppressors Large tumor suppressor 2 (LATS2) and Ras-related associated with diabetes (RRAD) transcription in NSCLC cells. Taken together, these findings demonstrate DUXAP10 exerts the oncogenic roles through binding with LSD1 and epigenetic silencing LATS2 and RRAD expression. Our investigation reveals the novel roles of pseudogene in NSCLC, which may serve as new target for NSCLC diagnosis and therapy.

Gambogenic acid induction of apoptosis in a breast cancer cell line.

BACKGROUND: Gambogenic acid is a major active compound of gamboge which exudes from the Garcinia hanburyi tree. Gambogenic acid anti-cancer activity in vitro has been reported in several studies, including an A549 nude mouse model. However, the mechanisms of action remain unclear. METHODS: We used nude mouse models to detect the effect of gambogenic acid on breast tumors, analyzing expression of apoptosis-related proteins in vivo by Western blotting. Effects on cell proliferation, apoptosis and apoptosis-related proteins in MDA-MB-231 cells were detected by MTT, flow cytometry and Western blotting. Inhibitors of caspase-3,-8,-9 were also used to detect effects on caspase family members. RESULTS: We found that gambogenic acid suppressed breast tumor growth in vivo, in association with increased expression of Fas and cleaved caspase-3,-8,-9 and bax, as well as decrease in the anti-apoptotic protein bcl-2. Gambogenic acid inhibited cell proliferation and induced cell apoptosis in a concentration-dependent manner. CONCLUSION: Our observations suggested that Gambogenic acid suppressed breast cancer MDA-MB-231 cell growth by mediating apoptosis through death receptor and mitochondrial pathways in vivo and in vitro.

Overexpression of polo-like kinase 1 and its clinical significance in human non-small cell lung cancer.

Polo-like kinase 1 is a serine/threonine kinase which plays an essential role in mitosis and malignant transformation. The aim of this study was to investigate the prognostic significance of polo-like kinase 1 expression and determine its possibility as a therapeutic target in non-small cell lung cancer. Semi-quantitative RT-PCR assay was performed to detect polo-like kinase 1 mRNA expression in non-small cell lung cancer cells or tissues. Immunohistochemistry was performed to detect polo-like kinase 1 protein expression in 100 non-small cell lung cancer tissue samples, and the associations of polo-like kinase 1 expression with clinicopathological factors or prognosis of non-small cell lung cancer patients were evaluated. RNA interference was employed to inhibit endogenous polo-like kinase 1 expression and analyzed the effects of polo-like kinase 1 inhibition on the malignant phenotypes of non-small cell lung cancer cells including growth, apoptosis, radio- or chemoresistance. Also, the possible molecular mechanisms were also investigated. The levels of polo-like kinase 1 mRNA expression in non-small cell lung cancer cell lines or tissues were significantly higher than those in normal human bronchial epithelial cell line or corresponding non-tumor tissues. High polo-like kinase 1 expression was significantly correlated with advanced clinical stage, higher tumor classification and lymph node metastasis of non-small cell lung cancer patients (P=0.001, 0.004 and 0.001, respectively). Meanwhile, high polo-like kinase 1 protein expression was also an independent prognostic molecular marker for non-small cell lung cancer patients (hazard ratio: 2.113; 95% confidence interval: 1.326-3.557; P=0.017). Polo-like kinase 1 inhibition could significantly inhibit in vitro and in vivo proliferation, induce cell arrest of G(2)/M phase and apoptosis enhancement in non-small cell lung cancer cells, which might be activation of the p53 pathway and the Cdc25C/cdc2/cyclin B1 feedback loop. Further, inhibition of polo-like kinase 1 could enhance the sensitivity of non-small cell lung cancer cells to taxanes or irradiation. Thus, polo-like kinase 1 might be a prognostic marker and a chemo- or radiotherapeutic target for non-small cell lung cancer.

[Detection and clinical features of MLL gene rearrangement in adult patients with acute leukemia].

This study was purposed to investigate the incidence of mixed lineage leukemia (MLL) gene rearrangement and partner gene types as well as the clinical features and prognosis of acute leukemia (AL) with this rearrangement through detection in adult AL using combination of 3 techniques, and to evaluate the clinical value of this combination detection. The MLL gene rearrangement in 183 cases of adult AL was detected by combination of conventional cytogenetics, split signal FISH and multiplex nested PCR. The results showed that the incidence of MLL rearrangements in adult patients with AL was low (8.2%), and MLL-AF4 fusion gene was most common and predominant in acute lymphoblastic leukemia (ALL), while the MLL-AF6 and MLL-AF9 were most frequent in acute myeloid leukemia (AML). Extramedullary involvements were found in 40% of MLL-rearranged AL patients, and 33.3% of patients with MLL-rearranged AL reached to complete remission within 30 days during induction chemotherapy. In addition, in this cohort of MLL-rearranged adult AL patients, the 3-month relapse rate and 6-month overall survival rate were 50.0% and 50.0% respectively. It is concluded that the rate of missed diagnosis of CC technique for patients with MLL-rearranged AL reached to 60% in this study, while the combination of CC, FISH and multiplex nested PCR has been confirmed to have important significance for evaluating prognosis and conducting clinical therapy of patients with MLL-rearranged AL.

MicroRNA-21 modulates chemosensitivity of breast cancer cells to doxorubicin by targeting PTEN.

BACKGROUND AND AIMS: Ovexpression of microRNA-21 (miR-21) is found in various human cancers. Our aim is to investigate the association of miR-21 expression with the sensitivity of breast cancer cells to doxorubicin (ADR). METHODS: The half maximal inhibitory concentration (IC(50)) value of ADR in resistant MCF-7/ADR or parental MCF-7 cells was determined by MTT assay. TaqMan RT-PCR or Western blot assay was performed to detect the expression of mature miR-21 and tumor suppressor gene (PTEN) protein. MCF-7 or MCF-7/ADR cell line was transfected with miR-21mimic or inhibitor. The IC(50) value of ADR was determined. Flow cytometry and TUNEL assays were performed to analyze apoptosis. The activity of caspase-3 was analyzed. RESULTS: The IC(50) of ADR in MCF-7 and MCF-7/ADR cells was 0.21 ± 0.05 and 16.5 ± 0.08 µmol/L, respectively. We showed that upregulation of miR-21 in MCF-7/ADR cells was concurrent with downregulation of PTEN protein. MiR-21 mimic or inhibitor could obviously affect the sensitivity of breast cancer cells to ADR. Moreover, miR-21 inhibitor could enhance caspase-3-dependent apoptosis in MCF-7/ADR cells. Overexpression of PTEN could mimic the same effects of miR-21 inhibitor in MCF-7/ADR cells and PTEN-siRNA could increase the resistance of MCF-7 cells to ADR. MiR-21 inhibitor could increase PTEN protein expression and the luciferase activity of a PTEN 3' untranslated region-based reporter construct in MCF-7/ADR cells. PTEN-siRNA could partially reverse the increased chemosensitivity of MCF-7/ADR cells induced by miR-21 inhibitor. CONCLUSIONS: Dysregulation of miR-21 plays critical roles in the ADR resistance of breast cancer, at least in part via targeting PTEN.