ABSTRACT
Background Retinal ganglion cell (RGCs) death following ischaemic insult is the major cause of a number of vision-threatening diseases.Recent studies confirmed that micro RNA (miR-30b) can alleviate hypoxy-induced cardiac injury.However,whether miR-30b can protect RGCs against oxygen-glucose deprivation damage is still not ellucidated.Objective The aim of this study was to investigate the protective effect of miR-30b on RGCs damage caused by oxygen-glucose deprivation.Methods The retinas were isolated from the eyeballs of eight SD rats aged postnatal 24 hours and RGCs were primarily cultured.The cells were divided into the recombinant adeno-associated virus (rAVV) control group,rAAV-miR-30b mimic group and AAV-miR-30b inhibitor group.Then the cells were transfected using rAVV-miR plasmid,rAAV-miR-30b mimic plasmid and AAV-miR-30b inhibitor plasmid,respectively for 6 days with the RGCs ∶ AAV as 1 ∶ 10 000.The cells were cultured with low glucose medium in hypoxygen incubator (5％ CO2,17％ N2,3％ O2) or 5％ CO2 incubator respectively for 24 hours.Cell viability was detected by cell counting kit-8 assay.The expression of Tubulin Ⅲ,a neuron specific marker,was detected by immunofluorescence technology to evaluate the survival of RGCs.The apoptosis and necrosis of the cells were assessed by Hoechst/PI double staining.Results The RGCs grew well with round shape and 1 3 processes 7 days after cultured in the normal cells.However,the RGCs were diminished and the cell process disrupted in the oxygen-glucose deprivation group.The relative vability of the cells was 3.310-±0.162 in the rAAV-miR-30b mimic group,which was significantly higher than 0.949±0.141 in the rAAV-miR-30b inhibitor group and 0.900±0.181 in the rAAV-miR control group(t=10.508,10.296,both at P＜0.001).It was positively expressed in survival RGCs,with the red fluorescence.The number of Tubulin Ⅲ+ cells was (13.800± 1.924)/field in the rAAV-miR-30b mimic group,showing a significant increase in comparison with (0.600±0.548)/field in the rAAV-miR-30b inhibitor group and (0.800± 1.304)/field in the rAAV-miR control group (t =15.141,14.912,both at P ＜ 0.001).Significant differences were found in the apoptosis rate and necrosis rate among the rAAV-miR-30b mimic group,rAAV-miR control group and PBS group (F=10.851,P=0.002;F=6.378,P=0.013),and the apoptosis rate and necrosis rate in the rAAV-miR-30b mimic group were considerably lower than those in the rAAV-miR control group and PBS group (all at P＜0.05).Conclusions The oxygen-glucose deprivation models can be established in RGCs by hypooxygic and low-glucose cultivation.rAAV encoding miR-30b mimics transfection can protect RGCs against oxygen-glucose deprivation damage.
ABSTRACT
Objective To investigate expressions of microRNA-21 (miR-21),PTEN,NF-κB,and caspase-9 in colon carcinoma and their possible mechanisms in progression of tumor.Methods Expressions of above-mentioned indexes and percentage of apoptotic cells in colon carcinoma,colon adenoma,and normal tissue specimen were detected.Results Expressions of miR-21,PTEN,N F-κB,and caspase9 in normal tissue were 0.39 ±0.02,50％,25％,and 50％.Expressions of them in colon adenoma were 0.62 ±0.06,50％,35％,and 55％,and those in colon carcinoma were 0.88 ±0.04,30％,75％,and 20％.Percentage of apoptotic cells were (24.64 ± 7.66) ％,(15.86 ± 1.44) ％,and (6.20 ± 2.57) ％,respectively.The above P-values were all less than 0.05.Expression of miR-21 was positively correlated with TNM stage,depth of infiltration,differentiated level and expression of NF-κB while inversely correlated with PTEN and caspase-9 expressions and percentage of apoptotic cells.The r-values were 0.647,0.297,0.259,0.519,-0.299,-0.388,and-0.931,respectively.Conclusions Hyperexpression of miR-21 participated in progression of colon carcinoma probably through down-regulating expressions of PTEN and caspase-9 and up-regulating expression of NF-κB and then suppressing cell apoptosis.
ABSTRACT
Objective To study the expressions of miRNAlet7 and Ras in non-small cell lung cancer ( NSCLC),and their correlations with clinicopathological features and survival time.Methods In-situ hybridization was used to detect the expression of let7,and SP immunohistochemistry to measure HMGA2 in 68 NSCLC cases ( group A) and 20 cases with normal lungs ( group B).Results The positive rate of let7 in group A was lower than that in group B (39.7％ vs 63.2％ ) ( P ＜0.05).The positive rate of Ras in group A was higher than that in group B (66.2％ vs 25.0％ ) ( P ＜0.01 ).The positive rate of let7 was not related to the age,gender,histological type,cell differentiation,and clinical stages of cancer patients(P ＞0.05).The positive rate of Ras was related to smoking,sex,and histological type of cancer( P ＜0.01 ),and was not related to cell differentiation,lymphatic metastasis,and clinical stages of cancer ( P ＞0.05).There was an obvious negative correlation between let7 and Ras( r =-0.627,P ＜0.01 ).The 2-year survival rate of let7-positive group was higher than that of the let 7-negative group ( x2 =4.84,P ＜0.05).No statistically significant difference was found between Ras-positive and-negative groups ( P ＞0.05 ).Conclusions The lower level of let7 expression,and high level of Ras expression have much to do with the carcinogenesis of NSCLC.The level of let7-positive expression is closely related to prognosis; while Ras may act in cooperativity in the occurrence and development of NSCLC.