CircTMEM87A promotes the tumorigenesis of gastric cancer by regulating the miR-1276/SLC7A11 axis.

BACKGROUND: Gastric cancer (GC) is a common malignancy with high incidence and mortality, and its pathogenesis involves the regulation of circular RNAs (circRNAs). However, the molecular mechanism of circTMEM87A in GC malignant progression is uncertain. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expressions of circTMEM87A, miR-1276, and solute carrier family 7 membrane 11 (SLC7A11). Western blot was applied to detect protein expression levels of EMT-related proteins (vimentin and E-cadherin) and SLC7A11. Cell counting kit-8 assay (CCK8) and thymidine analog 5-ethynyl-2'-deoxyuridine (EdU) were performed to assess cell proliferation. Apoptosis was investigated using flow cytometry. Transwell assay and wound healing assay were carried out to examine the migration of MKN-7 and AGS cells. The Cellular ROS Assay Kit, Iron Assay Kit, and GSH/GSSG Ratio Detection Assay Kit were utilized to monitor lipid ROS level, iron level, and GSH/GSSG ratio, respectively. The interaction between miR-1276 and circTMEM87A or SLC7A11 was investigated using dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. A xenograft mouse model was constructed to explore the function of circTMEM87A in tumor formation in vivo. RESULTS: CircTMEM87A and SLC7A11 were upregulated, while miR-1276 was downregulated in GC tissues and cells. Knockdown of circTMEM87A suppressed the proliferation and migration and promoted apoptosis and ferroptosis of GC cells. CircTMEM87A served as a sponge for miR-1276, and miR-1276 inhibitor relieved the circTMEM87A knockdown-induced effects on GC cell phenotypes. Similarly, SLC7A11, a downstream gene of miR-1276, rescued miR-1276 overexpression-induced effects on GC cell function. Furthermore, circTMEM87A knockdown inhibited GC cell tumor phenotypes in vivo. CONCLUSION: CircTMEM87A promoted the proliferation and migration and inhibited apoptosis and ferroptosis of GC cells by increasing SLC7A11 expression through binding to miR-1276.

[Effect of CDK Inhibitor LS-007 on Acute Lymphoblastic Leukemia and Its Mechanism].

OBJECTIVE: To study the effect of cyclin dependent kinase(CDK) inhibitor LS-007 on acute lymphoblastic leukemia and its mechanism. METHODS: The acute lymphocytic leukemia cell line was cultured and treated by LS-007, flavopiridol and ABT-199, then the changes of apoptosis-related factor mRNA and protein levels were detected by using mRNA quantitative PCR and Werstern blot. RESULTS: quantitative PCR and Western blot detection showed that the levels of antiapoptotic protein decreased significantly in acute lymphoblastic leukemia cells after LS-007 treatment, and the pro-apoptotic effect of LS-007 combined with ABT-199 was much better. CONCLUSION: LS-007 can affect the phosphorylation of RNA polymerase sites and promote cell apoptosis through changing the activities of CDK, thus having some positive significance for relieving acute lymphoblastic leukemia.

Targeting miR-155 suppresses proliferation and induces apoptosis of HL-60 cells by targeting Slug/PUMA signal.

Recent studies have shown that high miR-155 expression was associated with poor prognosis in patients with acute myelogeneous leukemia (AML). Furthermore, targeting miR-155 results in monocytic differentiation and apoptosis. However, the exact role and mechanisms of miR-155 in human AML remains speculative. HL-60 cells were treated with anti-miR-155 for 72 h. Cell growth and apoptosis in vitro were detected by MTT, BrdU proliferation, colony formation and flow cytometry assay. The effect of anti-miR-155 on growth of HL-60 cells was also evaluated in a leukemia mouse model. Slug cDNA and PUMA siRNA trannsfection was used to assess the signal pathway. Different protein expression was detected by western blot assay and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assay. The results shown that targeting miR-155 resulted in a 24-fold decrease of miR-155 expression compared to negative control in the HL-60 cells. Targeting miR-155 significantly downregulated Slug and upregulated PUMA expression, and decreased HL-60 cell growth by 70% , impaired colony formation by approximately 60%, and increased HL-60 cell apoptosis by 45%. Targeting PUMA reversed miR-155 sliencing-induced proliferation and apoptosis of HL-60 cells. Restoration of Slug decreased PUMA expression. In murine engraftment models of HL-60 cells, we showed that targeting miR-155 was able to reduce tumor growth. This was accompanied with decreased Slug expression and increased PUMA expression in these tumors. Collectively, our findings strongly suggest targeting miR-155 exhibited in vivo and in vitro antileukemic activities in AML through a novel mechanism resulting in inhibition of Slug expression and increase of PUMA expression.

Expression of TGF-ß1 and miRNA-145 in patients with diabetic foot ulcers.

The aim of the present study was to investigate the expression levels of transforming growth factor (TGF)-ß1 and microRNA (miRNA)-145 in patients with diabetic foot ulcers (DFUs). A total of 26 patients with DFUs requiring amputation were enrolled in the study between January 2013 and August 2014. In addition, 15 trauma patients undergoing amputation over the same time period were included as a control group. Samples were collected from the blood, the dorsalis pedis arteries and muscles of the amputated limbs. The expression levels of TGF-ß1 mRNA and miRNA-145 in these samples was detected using reverse transcription-quantitative polymerase chain reaction. The expression levels of TGF-ß1 protein were evaluated using western blot analysis. In comparison with the control, the protein and mRNA expression levels of TGF-ß1 in the DFU patients was significantly higher in the serum and the dorsalis pedis arteries, and significantly lower in the muscles with ulcers. In contrast, the expression levels of miRNA-145 was significantly lower in the blood and the dorsalis pedis arteries, and significantly higher in the muscles with ulcers in DFU patients compared with the control. The results of the present study suggested that there exists an inverse correlation between the expression levels of miRNA-145 and TGF-ß1 in patients with DFU; thus suggesting that miRNA-145 may regulate the expression of TGF-ß1 in patients with DFUs.

Low expression of microRNA-202 is associated with the metastasis of esophageal squamous cell carcinoma.

The present study aimed to determine the expression levels and biological functions of microRNA-202 (miR-202) in patients with esophageal squamous cell carcinoma (ESCC). A total of 60 patients with ESCC and 30 healthy individuals were enrolled and reverse transcription-quantitative polymerase chain reaction was performed to measure the expression levels of miR-202. In order to investigate the effects of miR-202 expression levels on the proliferative, migratory and invasive abilities of ESCC cells, methylthiazolyl-tetrazolium bromide proliferation, in vitro scratch and Transwell® chamber assays were performed. Expression levels of miR-202 were significantly decreased in the peripheral blood of patients with ESCC, which is associated with the degree of cell differentiation and lymph node metastasis (P<0.05). Following miR-202 transfection, cell proliferation was significantly inhibited (P<0.05). Cell migration and invasion was also significantly inhibited by miR-202 transfection (P<0.05). The results of the present study demonstrated that the expression of miR-202 inhibited the proliferation, migration and invasion of ESCC cells. Furthermore, low expression levels of miR-202 were detected in the peripheral blood of patients with ESCC, which is associated with the development, invasion and metastasis of ESCC.

Active screening of multi-drug resistant bacteria effectively prevent and control the potential infections.

Our objective is to determine if actively screen the multi-drug resistant bacteria (MDRB) infection in intensive care unit (ICU) to prevent, control, and decrease the infection rate and transmission of MDRB. The patients admitted in ICU of one hospital in 2013 were analyzed. The throat swab, blood, defecation, and urine of patients were actively collected for bacteria cultures to screen Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, and Acinetobacter baumannii in patients. All patients received screening of MDRB infection and colonization within 2 days and after 2 days of admission, the results showed that there were 418 infectious bacterial strains in total and P. aeruginosa was the main bacterium. The asymptomatic infection rates of P. aeruginosa, K. pneumonia, E. coli, S. aureus, and A. baumannii were 39.02, 24.74, 44.00, 29.17, and 33.33 %, respectively; the symptomatic infection rates were 60.98, 75.26, 56.00, 70.83, and 66.67 %. 59.70 % patients received antibiotics treatment, 27.45 % patients received trachea cannula, 32.95 % patients received mechanism ventilation, 2.27 % patients received arterial cannula or venous cannula and 4.00 % patients received indwelling urinary catheters. The main MDRB in ICU is P. aeruginosa. The active screening of MDRB infection and colonization can provide the opportunity to take the life-saving measure against MDRB and treat patients. This can decrease the infection risk and the nosocomial transmission of MDRB.

Protective effects of bilobalide on Aß(25-35) induced learning and memory impairments in male rats.

Alzheimer's disease (AD) is one of the major neurological diseases of the elderly. The deposition of Aß peptide, which can induce neuronal oxidative stress, inflammation and apoptosis, plays important roles in neuronal degeneration in AD. Currently, there are no effective drug treatment options for preventing or even slowing Alzheimer's disease. Bilobalide (BB) is one of the major active compounds extracted from Ginkgo biloba leaves. This study explored the neuroprotective effects of BB on Aß25-35 intrahippocampal injection induced AD model in rats. Our results showed that BB (4, 8 mg/kg) significantly protected against learning and memory impairments induced by Aß25-35 in Morris water maze. Besides, BB (4, 8 mg/kg) was able to attenuate the neuronal damage and apoptosis in frontal cortex and hippocampus CA1 in rats. In addition, the inhibition of TNF-α and Aß1-40 expression is also involved in the action mechanisms of BB in this experimental model. This study provided an experimental basis for the clinical application of BB in AD therapy.