ABSTRACT
Sepsis remains the leading cause of late death in trauma patients. Many bottleneck problems in the field of post-traumatic sepsis research have not been solved, which are mainly reflected in the lag of early warning research, limited preventive interventions and unclear diagnostic criteria. The authors focus on the early warning of sepsis, preventive intervention measures and early diagnostic criteria to guide the clinical positive response so as to reduce the late mortality caused by post-traumatic sepsis and improve the overall level of trauma treatment.
ABSTRACT
<p><b>BACKGROUND</b>Apoptosis is closely related to development of lung cancer. It is a strategy of lung cancer therapy to induce apoptosis. The aim of this study is to explore the effects of growth arrest-specific homeobox (Gax) transfection on apoptosis and expression of Bcl-2 and Bax proteins of human lung adenocarcinoma A549 cells.</p><p><b>METHODS</b>A549 cells were transfected with Gax gene by a replication-deficient adenovirus expressing the hemagglutinin-tagged Gax cDNA (Ad-Gax). Apoptosis of A549 cells was observed by transmission electronic microscope and terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) positive staining. Apoptotic rate of A549 cells was evaluated by flow cytometry. Expressions of Bcl-2 and Bax proteins in A549 cells were detected by immunocytochemistry.</p><p><b>RESULTS</b>Before Ad-Gax transfection, none or few of TUNEL-positive A549 cells were detected. After Ad-Gax transfection, a marked increase in TUNEL-positive staining occurred, especially at 24 h later. The ratio of apoptosis of A549 cellsin non-transfection group and transfection groups at 12 h, 24 h, 48 h were 0.25%, 12.57%, 17.29%, 15.03%, respectively. Compared with non-transfection group, the apoptotic rates of transfection groups increased significantly (Chi-square value was 7.357, 11.126 and 9.943 respectively, P < 0.01). The average optical density (AOD) of Bcl-2 protein in A549 cells in non-transfection group and transfection groups at 12 h, 24 h, 48 h were 2.02±0.07, 1.79±0.02, 1.25±0.51 and 1.21±0.24 respectively. Compared with non-transfection group, AOD of Bcl-2 protein in A549 cells in transfection groups decreased significantly (t value was 6.651, 7.089 and 7.438 respectively, P < 0.01). On the other hand, Bax protein expression in transfection groups increased, the AODs of Bax were 4.49±0.61, 4.24±0.37 and 3.95±0.43, respectively. Compared with non-transfection group (3.12±0.42), AOD of Bax protein in A549 celle in transfection groups increased significantly (t value was 7.469, 7.287 and 6.473 respectively, P < 0.01). In the Ad-Gax transfection groups the lower Bcl-2/Bax ratio was, the higher the apoptotic rate of A549 cells was (r=-0.49, P < 0.01).</p><p><b>CONCLUSIONS</b>Ad-Gax transfection can induce A549 cells apoptosis. Possible mechanism is that Gax can downregulate Bcl-2 protein expression and upregulate Bax protein expression, and A549 cells apoptosis is related to the Bcl-2/Bax ratio.</p>
ABSTRACT
<p><b>BACKGROUND</b>Lung cancer is the leading cancer of malignant tumor in China.It is the direction that poeple make efforts to seek gene therapy of lung cancer. The aim of this study is to explore the effects of transfected growth arrest-specific homeobox gene (Gax gene) on the proliferation and expressions of c-fos and c-jun mRNA in A549 cells.</p><p><b>METHODS</b>A549 cells were transfected with Gax gene by adenovirus. Expressions of Gax mRNA and protein were detected by RT-PCR and immunocytochemistry. The expressions of c-fos and c-jun mRNA were evaluated by RT-PCR. The proliferation inhibition effect of Gax transfection on A549 cells was evaluated by MTT assay.</p><p><b>RESULTS</b>Only in the A549 cells transfected with Gax gene the Gax expression was confirmed by RT-PCR and immunocytochemistry. Compared with that in the control group, c-fos and c-jun mRNA level decreased significantly in Gax-transfected A549 cells (t=7.755, P < 0.01; t= 5.938 , P < 0.01). MTT assay showed that the proliferation inhibition rates of A549 cells transfected by Ad-Gax for 24h, 48h and 72h were (47.35±5.36)%, (54.96±1.78)%, and (65.39±5.11)% respectively. And these proliferation inhibition rates were significantly higher than those in the control group (Chi-Square=7.152, 9.431 and 12.847, P < 0.01).</p><p><b>CONCLUSIONS</b>Gax gene can inhibit the proliferation of A549 cells. Its molecular mechanism may be through down-regulating the expressions of c-fos and c-jun.</p>
ABSTRACT
AIM:To explore the effects of Gax gene transfection on expressions of c-fos and c-jun mRNA and proliferation of pulmonary arterial smooth muscle cells (PASMCs) in rat under hypoxia. METHODS: PASMCs were transfected with Gax gene by Ad-Gax. Under normal oxygentention (21% O2) or hypoxia (2.5% O2) for 12 h condition, expressions of Gax mRNA and protein in PASMCs were detected by RT-PCR and immunocytochemistry. The expressions of c-fos and c-jun mRNA were evaluated by RT-PCR. [3H]-TdR incorporation was used to measure the PASMCs proliferation. RESULTS: The Gax overexpression in transfection group was confirmed by RT-PCR and immunocytochemistry. Under normal oxygentention or hypoxia, the c-fos and c-jun mRNA levels in transfection group were lower than those in the non-transfection group, respectively (P