miR-34a-5p might have an important role for inducing apoptosis by down-regulation of SNAI1 in apigenin-treated lung cancer cells.

Apigenin is a flavonoid with antioxidant and anticancer effects. It has been reported that apigenin inhibits proliferation, migration, and invasion and induces apoptosis in cultured lung cancer cells. However, there is little information on the involvement of microRNAs (miRNAs) in its effects. miRNA microarray analysis and polymerase-chain-reaction analysis of miRNAs revealed that treatment of human lung cancer A549 cells with apigenin up-regulated the level of miR-34a-5p. Furthermore, mRNA microarray analysis and the results of three microRNA target prediction tools showed that Snail Family Transcriptional Repressor 1 (SNAI1), which inhibits the induction of apoptosis, had its mRNA expression down-regulated in A549 cells treated with apigenin. Our findings suggest that apigenin might induce apoptosis by down-regulation of SNAI1 through up-regulation of miR-34a-5p in A549 cells.

Caspase-4 Mediates Restriction of Burkholderia pseudomallei in Human Alveolar Epithelial Cells.

Melioidosis is an infectious disease with a high mortality rate responsible for community-acquired sepsis in Southeast Asia and Northern Australia. The causative agent of this disease is Burkholderia pseudomallei, a Gram-negative bacterium that resides in soil and contaminated natural water. After entering into host cells, the bacteria escape into the cytoplasm, which has numerous cytosolic sensors, including the noncanonical inflammatory caspases. Although the noncanonical inflammasome (caspase-11) has been investigated in a murine model of B. pseudomallei infection, its role in humans, particularly in lung epithelial cells, remains unknown. We, therefore, investigated the function of caspase-4 (ortholog of murine caspase-11) in intracellular killing of B. pseudomallei The results showed that B. pseudomallei induced caspase-4 activation at 12 h postinfection in human alveolar epithelial A549 cells. The number of intracellular B. pseudomallei bacteria was increased in the absence of caspase-4, suggesting its function in intracellular bacterial restriction. In contrast, a high level of caspase-4 processing was observed when cells were infected with lipopolysaccharide (LPS) mutant B. pseudomallei The enhanced bacterial clearance in LPS-mutant-infected cells is also correlated with a higher degree of caspase-4 activation. These results highlight the susceptibility of the LPS mutant to caspase-4-mediated intracellular bacterial killing.

[Role of signaling pathway of long non-coding RNA growth arrest-specific transcript 5/microRNA-200c-3p/angiotensin converting enzyme 2 in the apoptosis of human lung epithelial cell A549 in acute respiratory distress syndrome].

Objective: To investigate whether long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5)/microRNA-200c-3p/angiotensin converting enzyme 2(ACE2) involved in the regulation of the apoptosis of human lung epithelial cell A549 in acute respiratory distress syndrome (ARDS). Methods: ARDS rat models were established and were divided into control, ARDS, ARDS+ pcDNA and ARDS+ pcDNA-GAS5 groups. Six hours after the establishment of ARDS rat model, arterial blood and lung tissues of the rats from the four groups were collected. The changes of partial pressure of oxygen (PO(2)) and partial pressure of CO(2) (PCO(2)) were analyzed and the expression of GAS5 in lung tissue was observed in these groups. Then, A549 cells were divided into control, lipopolysaccharide (LPS), LPS+ pcDNA, LPS+ pcDNA-GAS5, LPS+ pcDNA-GAS5+ pre-NC, LPS+ pcDNA-GAS5+ miR-200c-3p mimic groups. Quantitative real-time PCR (qRT-PCR) was conducted to measure lncRNA GAS5, ACE2 and miR-200c-3p levels. RNA immunoprecipitation and RNA pull-down assay were used to detect the combination between GAS5 and miR-200c-3p. Western blotting was used to detect the protein level of ACE2. Flow cytometry was used to observe the apoptosis of A549 cells in those groups. The data between groups were compared by t test. Results: In ARDS rat model, PO(2) value was significantly increased in ARDS+ pcDNA-GAS5 group than that in ARDS+ pcDNA group[(81.5±3.3) vs (57.5±5.1) mmHg, t=4.850, P<0.05], and PCO(2) value was significantly decreased in ARDS+ pcDNA-GAS5 group than that in ARDS+ pcDNA group[(50.6±1.9) vs (64.0±1.9) mmHg, t=5.940, P<0.05]. LncRNA GAS5 level in A549 cells of LPS group decreased significantly than that in control group (0.43±0.01 vs 1.01±0.01, t=0.242, P<0.05). Compared with LPS+ pcDNA group, ACE2 expression increased significantly in LPS+ pcDNA-GAS5 group (0.85±0.04 vs 0.34±0.02, t=1.800, P<0.05). Compared with LPS+ pcDNA-GAS5+ pre-NC group, ACE2 expression decreased significantly in LPS+ pcDNA-GAS5+ miR-200c-3p mimic group (0.62±0.01 vs 0.84±0.02, t=9.440, P<0.05). Compared with control group, the percentage of A549 cell apoptosis promoted significantly in LPS group (25.90±0.61 vs 7.90±0.22, t=0.257, P<0.05). Compared with LPS+ pcDNA group, the percentage of A549 cell apoptosis suppressed significantly in LPS+ pcDNA-GAS5 group (10.50±0.37 vs 26.37±0.45, t=1.760, P<0.05). Compared with LPS+ pcDNA-GAS5+ pre-NC group, the percentage of A549 apoptosis promoted significantly in LPS+ pcDNA-GAS5+ miR-200c-3p mimic group (19.07±0.56 vs 10.87±0.26, t=0.643, P<0.05). Conclusion: In ARDS, down-regulation of lncRNA GAS5 decreases ACE2 expression through increasing miR-200c-3p to promote the apoptosis of A549 cells, thus to promote the progression of ARDS.

Study of mechanisms of hesperidin onanti-lung cancer effect based on microfluidic chip technology / 中国药理学通报

Aim To investigate the effect of hesperidin on human lung cancer cell A549 and the possible mechanism.Methods The cell apoptosis and necrosis of A549 treated with hesperidin were measured by the Hoechst 33342/PI fluorescent dye based on microfluidic chip technology.Cell cycle and apoptosis rate were evaluated by flow cytometry(FCM).The expressions of the related genes were detected through the real-time fluorescent quantitative PCR technology(RT-PCR) including VEGF, PI3K and PTEN.The protein expressions of Bcl-2, Cyclin B1, PI3K, Akt and PTEN were detected by Western blot after hesperidin intervention.Results The proliferation of A549 cells was significantly inhibited by hesperidin in a dose-dependent manner.FCM results showed that hesperidin could not only influence the G0/G1 phase and S phase, but also promote the apoptosis of lung cancer cells.Meanwhile, the apoptosis and necrosis rate was increased from(6.7±0.6)% to(27.9±1.1)% compared with that of control group(P<0.05).From the level of molecular, the gene expressions of VEGF and PI3K were decreased, while the PTEN was increased after hesperidin stimulation.Western blot results showed that the expression of protein Bcl-2, Cyclin B1 and Akt were decreased, which all showed close relationship with cell apoptosis, cell cycle and PI3K-Akt signaling pathway.The expression of PI3K was increased, but the change of PTEN was not statistically significant compared with that of control group.Conclusion Hesperidin induces lung cancer cell apoptosis through PI3K-Akt signaling pathway, which blocks cancer cell division and destroys the balance of related protein expression.

Effects of rhTIMP-3 combined with DDP on growth inhibition and apoptosis of lung cancer cell A549 / 西安交通大学学报(医学版)

Objective To study the effects of restructuring tissue inhibitor of matrix metatloproteinase-3 (rhTIMP-3) in combination with cisplatin (DDP) on the growth and apoptosis of A549 lung cancer cell line.Methods We made individual and combined use of different concentrations of rhTIMP-3 and DDP on A549 cells.Methyl thiazoyl terazolium (MTT) colorimetry was used to analyze cell growth inhibition,and flow cytometry technique was used to determine the cell cycle distribution and apoptosis rate.Results rhTIMP-3 and DDP both could inhibit the proliferation of A549 cells.rhTIMP-3 exerted its effect in the time-and concentration-dependent manners while DDP did so in the concentration-dependent manner;both induced the apoptosis of A549 cells.rhTIMP-3 could make the cells stay in S and G2/M phases,and DDP made the cells stay in S phase.The combination of them obviously strengthened the inhibition of A549 cell growth,and had obvious synergy in inducing apoptosis.Conclusion Both rhTIMP-3 and DDP can inhibit the proliferation of A549 cells and induce their apoptosis.The combined use of them not only can increase the inhibition of cell growth but also has synergy in inducing cell apoptosis.

Effects of PM2.5 exposure on autophagy and apoptosis in A549 cells / 实用医学杂志

Objective To investigate the effect of PM2.5 airborne particulate matter with a mean diameter of less than 2.5μm exposure on autophagy and explore the links between autophagy and apoptosis in human lung cancer cells(A549). Methods A549 cells were exposed to 100μg/mL PM2.5 with or without 3-MA(autophagy inhibitor)for various periods of 0、2、4、12 or 24 hrs. Autophagy in A549 cells was assessed by determining the lev-el of LC3(a known autophagy marker)using confocal microscopy. The level of microtubule-associated protein 1 light chain 3(LC3) Ⅱ conversion and Bax (a pro-apoptotic protein) was detected by western blotting. Results The expression of LC3 and the ratio of LC3-II/LC3-I in A549 cells was significantly increased and Bax was signifi-cantly decreased following exposure to PM2.5100 μg/mL for 24 h in a time-dependent manner(P < 0.05). After treated with 100 μg/mL PM2.5,the formation of LC3 in A549 cells as evidenced by the intensity of intracellular fluorescence was significantly increased ,and autophageosomes were observed around nucleus in A549 cells. Fur-thermore blockage of autophagy by 3-MA led to a significant increase in the pro-apoptotic protein Bax. Conclu-sion PM2.5 exposure induces autophagy which may protect against apoptosis induced by PM2.5 in A549 cells.

Petroleum ether extract of Chenopodium album L. prevents cell growth and induces apoptosis of human lung cancer cells.

Chenopodium album L. is a common edible herb distributed in China that has been used as a traditional Chinese medicine for antiviral, antifungal, anti-inflammatory and cancer treatment. However, to the best of our knowledge no previous reports have investigated its the function of its phytochemical extracts in lung cancer cells. The purpose of the present study was to assess the anticancer activities of the phytochemical extracts of C. album L. on human non-small cell lung cancer A549 cells. The present findings demonstrated that the petroleum ether (PE) extract of C. album L. exhibited significant growth inhibitory effects on A549 with an IC50 value of 33.31±2.79 µg/ml. As determined by MTT and colony formation assays, its growth inhibitory effects were dose- and time-dependent. Furthermore, PE extract-treated A549 cells exhibited dose-dependent cell growth arrest at the G1 phase of the cell cycle and cell apoptosis was induced. These results provide useful data on the anticancer activities of C. album L. in human lung cancer and demonstrated the novel possibilities of this plant in developing lung cancer therapies.

Characteristics of Carbon Material Formation on SBA-15 and Ni-SBA-15 Templates by Acetylene Decomposition and Their Bioactivity Effects.

Carbon spheres and tubes were formed from acetylene decomposition on SBA-15 and Ni-SBA-15 at 650-850 °C. At 650 °C, the decomposed carbons covered the surface of the support, and no carbon spheres and filament materials were formed. Carbon sphere formation occurred at 750 °C-850 °C; with diameters ranging from 0.8 µm-1.1 µm. For Ni-SBA-15, the diameters of the spheres and filaments were 0.8 µm and 62 nm, respectively, at 650 °C. At 750 °C, the diameter of the ball carbon materials ranged from 0.7 µm-0.8 µm, the diameter of the carbon tubes formed was 120-130 nm, and their pore diameter was 8.0 nm-11 nm. At 850 °C, the diameters of ball carbon materials and carbon tubes were similar to those of the materials at the formation temperature, 750 °C. Si, O and C were the main constituents of SBA-15; Ni-SBA-15 and carbon material formation supports. High-ring PAHs (such as BaP (five rings); IND (six rings); DBA (five rings) and B[ghi]P (six rings)) exist in carbon materials. SBA-15 revealed insignificant cytotoxicity, but Ni-SBA-15 inhibited the proliferation of human lung cancer cells (A549). Less inhibition on cell viability and reactive oxidative species (ROS) generation on A549 were determined for carbon material formation on the Ni-SBA-15 compared to the Ni-SBA-15.

Effect of baicalin on apoptosis induced by H1N1 virus in vitro and its mechanism / 中国药理学通报

Aim To investigate the regulatory effects of baicalin on apoptosis induced by virus H1 N1 in hu-man pulmonary carcinoma cell A549 . Methods The chips were used to screen the RNA samples in virus-in-fected A549 cells. Differentially expressed genes were selected in the pathway of apoptosis. The mRNA ex-pressions of caspase-3 and -8 were verified by Real-Time PCR. Results With the DNA microarray, the functions of differentially expressed genes involved in apoptosis biological pathways were analyzed by Kyoto Encyclopedia of Genes and Genomes ( KEGG ) Path-way databases. caspase-3, -7, -8, -10, TRAIL, MYD88 , IL1 A and IL1 B were up-regulated in virus-in-fected group. Oseltamivir could down-regulate gene ex-pressions of caspase-3 ,-4 and-8 . High-dose of baica-lin could down-regulate gene expressions of caspase-3 ,-4,-6 and -8. Except gene expressions of above, low-dose of baicalin could also down-regulate gene expres-sions of IL1RAP and Cn. Real-Time PCR experiments showed that baicalin could significantly decrease mR-NA expression of caspase-3 , -4 , -6 , -8 , IL1 RAP and Cn ( P < 0. 01 ) , compared with the virus-infected group. The results also figured that the interference ef-ficacy of low-dose baicalin was better than that of high-doses. As expected, real-time PCR data were in good agreement with the microarray assay. Conclusions Baicalin can be detected in their suppression effect of caspase-3,-4,-6, and -8 mRNA expression, so it re-sists against the apoptosis to fight against influenza vi-rus in vitro.

Effect of berbamine on apoptosis in human pulmonary carcinoma cell A549 and its mechanism / 中草药

Objective: To investigate the effect of berbamine (BBM) on the induction of apoptosis in human lung cancer cell A549 cells and the activity of TNF-α-JNK signaling pathway. Methods: After the A549 cells being treated with BBM at different concentration, the inhibitory effect of BBM on proliferation was detected by MTT assay. Cell morphological changes were detected by light microscope. Alteration of apoptosis rate of A549 cells was determined by Annexin V/PI double staining. Western blotting was used to detect the activity of apoptosis-related proteins, including Bcl-x, Caspase-3, and PAPR. The expressions of c-jun N-terminal kinase (JNK) and p-JNK were determined by Western blotting. Changes of tumor necrosis factor-alpha (TNF-α) were detected by fluorescent quantitative PCR and ELISA, respectively. Finally, the impacts of BBM on the proliferation and apoptosis of A549 cells were detected in the absence or presence of a JNK inhibitor. Results: BBM significantly inhibited the growth of A549 cells in a dose-dependent manner. The IC50 of 24 h was 9.01 μmol/L. Cells treated with BBM showed the typically morphological characteristics of apoptotic cells. Annexin V/PI double staining test indicated that BBM could induce the apoptosis of A549 cells in a dose-dependent manner. The early apoptotic population of cells treated with 10 μmol/L BBM was 13.8%, which was 5.6 times higher than that of the control. BBM decreased the expression of anti-apoptotic protein Bcl-x and increased the activity of proapoptotic proteins of caspase-3 and PARP. The mRNA and the protein expression levels of TNF-α were significantly increased by BBM treatment. The p-JNK expression was also dramatically up-regulated after BBM treatment. The effects of BBM on the proliferation and apoptosis in A549 cells were significantly reduced when JNK pathway was blocked. Conclusion: BBM could inhibit the growth and induce the apoptosis of A549 cells, and its mechanism may be related to the activated TNF-α-JNK signaling pathway.

Supernatant of Toxoplasma gondii culture inhibits the proliferation of human lung cancer cell line A549 / 基础医学与临床

Objective To investigate whether there is an inhibition of the human lung cancer cell line A549 induced by the culture supernatant of Toxoplasma gondii in vitro and the mechanism of the inhibition. Methods A549 cells 5 x 10~4mL~(-1) were cultured and harvested. The cells were treated for different hours with different concentrations of Toxoplasma gondii culture supernatant (the concentrations of tachyzoites were 4×10~7mL~(-1), 8 × 10~7mL~(-1), 16 ×10~7mL~(-1) respectively). Growth inhibition rate was measured with the MTT method; Cell cycle was checked with flow cytometer. Western blot was used to detect the level of cyclinBl and cdc2 of cells. Results The culture supernatants of Toxoplasma gondii inhibited proliferation of A549 cells in a time-dose dependent manner. Cell cycle was significantly stopped at G_2/M phase by the culture supernatants with FCM technology. The culture supernatant of Toxoplasma gondii reduced the expressions of gene cyclinBl and cdc2 of A549 cells. Conclusion The culture supernatant of Toxoplasma gondii may inhibit A549 cell and arrest the cell cycle of A549 cells mainly by regulating the expression of gene cyclinBl and cdc2.

Rapamycin induces apoptosis of lung adenocarcinoma cell A549 under hypoxia and its molecular mechanism / 肿瘤

Objective:To investigate the molecular mechanism underlying apoptosis of lung adenocarcinoma cell line A549 induced by rapamycin, a type of mammalian target of rapamycin (mTOR) signal pathway inhibitor, combined with hypoxia treatment. Methods:Rapamycin was applied to treat A549 cell line under hypoxia for 16 h. Then the discrepancy of cell apoptosis between treated and untreated control was compared by Hochest 33258 staining. After being treated with rapamycin combined with hypoxia, the mRNA and protein expressions of survivin, a kind of anti-apoptotic molecule, were tested by real-time PCR and Western blotting. Western blotting was employed to test the difference of hypoxia-inducible factor (HIF)-1α expression level before and after rapamycin was added. In additon, chromatin immunoprecipitation(ChIP) assay was further applied to explore the mechanism underlying the effects of rapamycin under hypoxia in inducing apoptosis of A549 cells. Results:Rapamycin induced apoptosis of A549 cell line under hypxia in vitro. In A549 cell line, the expressions of survivin at mRNA (P<0.01) and protein levels, were both decreased by rapamycin combined with hypoxia treatment. Besides, ChIP assay revealed that rapamycin inhibited the expression of survivin at the transcriptional level through decreasing the hypoxia-induced up-regulation of HIF-1α and its binding with the promoter of survivin gene. Conclusion:Rapamycin exerted anti-tumor effects by inhibiting the expression of HIF-1α and decreasing the binding of HIF-1α with the promoter of survivin gene, thereby down-regulating the increase in the expression of apoptosis inhibiting gene survivin.

Effect of hypoxia on migration and adhesion of human pulmonary adenocarcinoma A549 cells / 肿瘤

Objective: To evaluate the effect of hypoxia on migration, invasion and adhesion to endothelial cells of human pulmonary adenocarcinoma A549 cells. Methods: Wound-healing and Transwell invasion assays were performed to study the effect of hypoxia on migration and invasion of A549 cells. Cell adhesion test was used to detect the adhesion of A549 cells to a monolayer of human umbilical vein endothelial cells (HUVECs). Immunofluorescence assay was used to evaluate the effect of hypoxia on distribution of E-cadherin, β-catenin, and F-actin. The luciferase reporter gene assay was performed to detect the transcription of hypoxia-inducible factor-1 (HIF-1) alpha. Results: Hypoxia promotes A549 cell migration, invasion, and adhesion to endothelial cells, and modulated the distribution of E-cadherin and β-catenin and rearrangement of actin cytoskeletal protein, and up-regulated HIF-1-dependent reporter gene expression in A549 cells. Conclusion: Hypoxia promoted A549 cell migration, invasion, and adhesion to endothelial cells by upregulating HIF-1-dependent gene expression, subsequently affecting the redistribution of E-cadherin and β-catenin and rearrangement of F-actin cytoskeletal protein.

The Effect of CIK Cell on Apoptosis of Lung Cancer Cell A549 / 医学研究杂志

Objective To investigate the inhibitory effects of CIK cell on apoptosis of lung cancer cell A549 in vivo. Methods CIK cells were induced by culturing PBMC with regular method and cell apoptosis was detected.Results Electron microscopic observations showed that CIK cells could induce the lung cancer cells A549 to apoptosis. Flow cytometry(FCM)demonstrated that apoptosis cells of lung cancer cells A549 were increased in CIK group as compared with the control group. Conclution CIK cells can induce the apoptosis of lung cancer cells A549.