Characterization of Two Human Lung Adenocarcinoma Cell Lines by Reciprocal Chromosome Painting

Lung cancer is a leading cause of cancer death worldwide. Some lung cancer patients correlate with a gas of radon besides smoking. To search for common chromosomal aberrations in lung cancer cell lines established from patients induced by different factors, a combined approach of chromosome sorting, forward and reverse chromosome painting was used to characterize karyotypes of two lung adenocarcinoma cell lines： A549 and GLC-82 with the latter line derived from a patient who has suffered long-term exposure to environmental radon gas pollution. The chromosome painting results revealed that complex chromosomal rearrangements occurred in these two lung adenocarcinoma cell lines. Thirteen and twenty-four abnormal chromosomes were identified An A549 and GLC-82 cell lines, respectively. Almost half of abnormal chromosomes in these two cell lines were formed by non-reciprocal translocations, the others were derived from deletions and duplication/or amplification in some chromosomal regions. Furthermore, two apparently common breakpoints, HSA8q24 and 12q14 were found in these two lung cancer cell lines.

Empirical studies about quercetin increasing chemosensitivity on human lung adenocarcinoma cell line A549

Objective： The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin （DDP） and vincristine （VCR） in vitro respectively and its possible antitumor mechanism. To provide experimental proof for clinical combination application. Methods： Using intermittent administration of high dose VCR, human lung adenocarcinoma sensitive cell line （A549/S） was induced to VCR- resistant human lung adenocarcinoma cell line （A549NCR）. MTT assay was adapted for examing the 50% inhibition （IC50） value of DDP and VCR on A549/S and A549/VCR when quercetin combined with DDP and VCR respectively. Results： IC50 of DDP on A549/S and A549/VCR was 10.18 and 12.35 mg/L, and the IC50 of VCR on the two cell lines was 1.21 and 12.77 rag/L, respectively. The resistance fold of A549/VCR on VCR and DDP was 10.55 and 121, respectively. When quercetin at concentration of 50, 100 and 200 pmol/L in combination with DDP and VCR respectively, the IC50 of DDP and VCR on A549/S and A549/VCR were obvious decreased （P 〈 0.05 - P 〈 0.01）. Conclusion： The experiment results suggested that quercetin could increase the chemosensitivity and partly revise the resistance of A549NCR.

Reversal effect of recombinant human Endostatin on cisplatin resistance in A549/DDP human lung adenocarcinoma cells in vitro

Objective： Recombinant human Endostatin （rh-Endostatin, YH-16） can reverse cisplatin resistance in A549/DDP cells. However, the possible effect of rh-Endostatin in reversing DDP-resistance in A549/DDP cells and the mechanism are needed to be investigated. Methods： Lung adenocarcinoma cell line A549 and its DDP-resistant cell line A549/DDP were treated with DDP and/or recombinant human Endostatin. Difference in drug resistance was analyzed between different regi- mens and between different cell lines after a 72 h-treatment in vitro. And below the non-cytotoxic concentration of rh-End- ostatin, the possibility of rh-Endostatin in reversing DDP-resistance in A549/DDP was evaluated. The resistance protein which was detected in the study included P glycoprotein （P-gp） and topoisomerase II （Topo-II）. Results： Rh-Endostatin below 400 IJg/mL showed no cytotoxicity in either A549 or A549/DDP after 72 h-treatment with it. The inhibited concentration of 50% （IC50） observed for DDP was （0.79 _＋ 0.05） IJg/mL in A549 and （13.2 ＋ 1.1） in A549/DDP respectively. IC50 was reduced to 2.57 ＋ 0.05 #g/mL in A549/DDP treated by rh-Endostatin below the non-cytotoxic concentrations in combination with DDP, with a reversal fold （RF） of 5.14 and a relative reversal rate of 85.6%. Apoptotic rates were 2.01%, 13.47% and 29.26% re- spectively for cells treated with rh-Endostain, DDP, and the combination. The rate of the A549/DDP control group was 0.99%. The expression level of P-gp or Topo-II was higher in A549/DDP cells than in A549 cells. Rh-Endostatin may partially reverse DDP-resistance in A549/DDP cells in vitro, with a probable mechanism related to lowering expression of P-gp and Topo-II. Conclusien： Rh-Endostatin of non-cytotoxic dose partially reversed cisptatin resistance in cisplatin-resistant human lung adenocarcinoma cell line A549/DDP. Rh-Endostatin reversed the resistance of A549/DDP cells to DDP, which may be related to decreased protein expression of P-gp and Topo-II in A549/DDP cells.

Effects of paclitaxel on cell proliferation and apoptosis and its mechanism in human lung adenocarcinoma A549 cells

Objective： To investigate the effect of paclitaxel on cell proliferation and apoptosis of human lung adenocarcinoma A549 cells line and its mechanism in vitro. Methods ： Cell growth inhibition of paclitaxel on A549 cells was analyzed by MTT assay. Cell apoptosis was detected by DNA cytofluorometry, Hoechst33258 staining when treated with paclitaxel for 48 hours. Meanwhile, Cell cycle and apoptotic rate were analyzed by flow cytometry. The protein expressions of Bax and Bcl-2 were studied by Western Blot. Results： Paclitaxel inhibited the proliferation of A549 cells in a time-and dose-dependant manner. Hoechst33258 staining indicated that apoptosis was induced by paclitaxel. After treated for 48 hours, cell apoptosis rates of 25 nmo1/L, 50 nmol/L and 100 nmol/L paclitaxel groups were 11.52 ± 1.94% ,17.73 ±2.53%, and 29.32 ±5.51% respectively, which were significantly higher than those of control group 5.88 ±1.07%（all P 〈 0.01 ）, and apoptosis rate increased in dose-dependant manner. Meanwhile, G2/M stage cell percentage of 25 nmol/L, 50 nmol/L and 100 nmol/L paclitaxel groups were 42.52 ± 6.25%, 40.46 ± 5.81%, and 35.34 ±6.17% respectively,which were significantly higher than that of control group 22.32 ± 3.30%（all P 〈 0.01 ）; Western blot showed that paclitaxel increased the expression of Bax and decreased the expression of Bcl-2 in dose-dependant manner. Conclusion： Paclitaxel can inhibit A549 cell proliferation in a time-and dose-dependant manner. Its mechanism may be related to arresting cell cycle in G2/M stage and induce cell apoptosis by up-modulating Bax expression and down-modulating Bcl-2 expression.

Effect of three suture lines on the proliferation and cell cycle of lung adenocarcinoma cell A549 in vitro

Objective： The interaction of cell and medical biomaterial is one of the significant factors to affect clinical application of medical biomaterial. This research is to investigate three of suture lines how to affect the proliferation and cell cycle of lung adenocarcinoma cell A549 in vitro. Methods： Three of suture lines were respectively cultivated with lung adenocarcinoma cell A549, after of 72 hours, we detected absorptions of each group by MTT method in order to reflect the proliferation of lung adenocarcinoma cell A549, and also examined percentage of G1 period cells and S period cells of each group by flow cytometry. Results： Different of suture lines had different effects on the proliferation and cell cycle of lung adenocarcinoma cell A549 （P 〈 0.05）. The effect of absorbent suture line was the strongest on the proliferation and cell cycle of lung arlenecarcinoma cell A549, the effect of chorda serica chirurgicalis was medium, and the effect of slide wire was poor. Different length of each suture line had different effects on the proliferation and cell cycle of lung adenocarcinoma cell A549 （P 〈 0.05）, Conclusion： Three of suture line materials have different effects on the proliferation and cell cycle of lung adenocarcinoma cell A549, with dose-effect relationship.

Inhibitory effect of toremifene monotherapy or combined with gemcitabine on A549 human lung adenocarcinoma cells

Objective： The aim of this study was to investigate the effect of toremifene on A549 human lung adenocarci- noma cells, and its sensibilization with gemcitabine, so that to provide a new clinical approach for non-small-cell lung cancer （NSCLC）. Methods： A549 cells were seeded into 96-well plates and exposed to different agents （gemcitabine or gemcitabine with toremifene）. The cytotoxicity of each agent was evaluated by MTT, cell cycle and apoptotic rate were detected by flow cytometry （FCM）. Results： 1. By using FCM, we found A549 cells in S and G2/M phases with toremifene decreased but increased in G0/G1 phase. The higher concentration of toremifene, the more decreased was when compared with the control group. 2. FCM showed toremifene＇s apoptosis effect on A549 cells increased with its increasing dose. 3. By MTT, toremifene had no cytotoxic effect on A549 cells at the concentration of 5 or 2.5 pmol/L. The IC5o of gemcitabine to A549 was 34.51 tJmol/L, and the combined group was 13.59 pmol/L. Conclusion： Toremifene could inhibit the growth of A549 human lung adenocarcinoma cells. Toremifene combined with gemcitabine showed significantly remarkable chemotherapy sensibilization on A549 human lung adenocarcinoma cells.

Antineoplastic effects of deoxyelephantopin,a sesquiterpene lactone from Elephantopusscaber, on lung adenocarcinoma (A549) cells

OBJECTIVE： Deoxyelephantopin, a sesquiterpene lactone from Elephantopus scaber, showed inhibition of the growth of various tumor cells in vitro. In the present study, we investigated the cytotoxicity and apoptosis-inducing capacity of deoxyelephantopin on lung adenocarcinoma （A549） cells. METHODS： The cytotoxic effect of deoxyelephantopin on A549 cells and normal lymphocytes was evaluated using 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay and 50% inhibitory concentration （IC50） value was determined. The self-renewal and proliferating potential of A549 cells after treatment with deoxyelephantopin were examined by colony formation assay. Cellular morphology of deoxyelephantopin-treated cells was observed using phase- contrast microscopy. The induction of apoptosis was evaluated using acddine orange and ethidium bromide staining, Hoechst 33342 staining, terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end-labeling （TUNEL） assay, DNA fragmentation analysis and Annexin V-fluorescein isothiocyanate staining by flow cytometry. Activation of caspases was detected using fluorogenic substrate specific to caspases 2, 3, 8 and 9 and flow cytometric analysis. The total cellular DNA content and expression of cleaved poly （ADP-ribose） polymerase was also analyzed. RESULTS： Deoxyelephantopin exhibited cytotoxicity to A549 cells （IC50 = 12.287 μg/mL）, however, there was no toxicity towards normal human lymphocytes. Deoxyelephantopin suppressed the colony-forming ability of A549 cells in a dose-dependent manner. Acridine orange, ethidium bromide and Hoechst 33342 staining showed cell shrinkage, chromosomal condensation and nuclear fragmentation, indicating induction of apoptosis. Deoxyelephantopin increased apoptosis of A549 cells, as evidenced by more TUNEL-positive cells. DNA fragmentation and Annexin V staining revealed late-stage apoptotic cell population. Deoxyelephantopin inhibited A549 cell growth by cell cycle arrest at G2/M phase and induced apoptosis through both extrinsic and intrinsic pathways. CONCLUSION： These results suggest that deoxyelephantopin has great potential as a new chemotherapeutic agent to be developed further for the treatment of lung cancer.

Effects of PI3K Inhibitor NVP-BKM120 on Acquired Resistance to Gefitinib of Human Lung Adenocarcinoma H1975 Cells

The effects of class I PI3K inhibitor NVP-BKM120 on cell proliferation, cell cycle distri- bution, cellular apoptosis, phosphorylation of several proteins of the PI3K/AKT signaling pathway and the mRNA expression levels of HIFl-ct, VEGF and MMP9 in the acquired gefitinib resistant cell line H1975 were investigated, and whether NVP-BKM120 can overcome the acquired resistance caused by the EGFR T790M mutation and the underlying mechanism were explored. MTT assay was performed to detect the effect of gefitinib, NVP-BKM120, NVP-BKM120 plus 1 ~unol/L gefitinib on growth of H1975 cells. The distribution of cell cycle and apoptosis rate of H1975 cells were examined by using flow cytometry. The mRNA expression levels of tumor-related genes such as HIFI-a, VEGF and MMP9 were detected by using real-time quantitative PCR. Western blotting was used to detect the ex- pression level of phosphorylated proteins in the PI3K/AKT signaling pathway, such as Ser473-p-AKT, Ser235/236-p-S6 and Thr70-p-4E-BP1, as well as total AKT, $6 and 4E-BP1. The results showed that the NVP-BKM120 could inhibit the growth of H1975 cells in a concentration-dependent manner, and H1975 cells were more sensitive to NVP-BKM120 than gefitinib （IC50：1.385 vs. 15.09 ~mol/L respec- tively）, whereas combination of NVP-BKM120 and gefitinib （1 ~trnol/L） did not show more obvious ef- fect than NVP-BKM120 used alone on inhibition of cell growth （P〉0.05）. NVP-BKM120 （1 ~unol/L） increased the proportion ofH1975 cells in G0~G1 phase and the effect was concentration-dependent, and 2 ~maol/L NVP-BKM120 promoted apoptosis ofH1975 cells. There was no significant difference in the proportion of H1975 cells in G0-G1 phase and apoptosis rate between NVP-BKM120-treated alone group and NVP-BKM120 plus genfitinib （1 ~unol/L）-treated group or between DMSO-treated control group and gefitinib （1 Ixmol/L）-treated alone group （P〉0.05 for all）. It was also found that the mRNA expression levels of these genes were down-regulated by NVP-BKM120 （1 ~unol/L）, and NVP-BKM120 （1 ~tmol/L） or NVP-BKM120 （1 pmol/L） plus gefitinib （1 ~tmol/L） obviously inhibited the activation of Akt, $6 and 4E-BP1 as compared with control group, but single use of gefitinib （1 pmol/L） exerted no significant effect. These data suggested that NVP-BKM120 can overcome gefitinib resistance in H1975 cells, and the combination of NVP-BKM120 and gefitinib did not have additive or synergistic effects. It was also concluded that NVP-BKM120 could overcome the acquired resistance to gefitinib by down-regulating the phosphorylated protein in PI3K/AKT signal pathways in H1975 cells, but it could not enhance the sensitivity of H 1975 cells to gefitinib.

The effect of antisense oligodeoxynucleotides targeting Aurora A kinase on cell proliferation and chemosensitivity to paclitaxel in human lung cancer cell line A549

Objective： Aurora A kinase representing a family of evolutionadly conserved mitotic serine/threonine kinases has been found elevated in human lung adenocarcinoma cell line A549. It is suggested that the overexpression of Aurora A contributes to the carcinogenesis, chromosomal instability （CIN）, and de-differentiation of lung cancers. To address its possibility as a therapeutic target for lung cancer, we employed the antisense oligodeoxynucleotide （ASODN） technique to inhibit Aurora A expression and investigate its effects on tumor growth and cell cycle of A549, as well as the chemosensitivity to paclitaxel. Methods： Aurora AASODN was synthesized and transfected into A549 cells by lipofectAMINE 2000. Aurora A mRNA and protein expression were examined by reverse transcription-polymerase chain reaction （RT-PCR） and Western blot respectively. Cell cycle distribution was observed by flow cytometer. MTT assay was used to evaluate cell inhibition ratio before and after transfection. Results： The proliferation of the A549 cells was inhibited by Aurora A ASODN dose and time dependently. It was also observed that the IC50 of A549 cells after 48 hours＇ treatment of ASODN was about 300 nmol/L and under such circumstances, the Aurora A mRNA and protein expression significantly decreased （P 〈 0.05）, along with the induction of accumulation of cells in S phase and the G2-M transition. Furthermore, cell inhibition ratio of the combination of Aurora AASODN and paclitaxel was higher significantly than paclitaxel （P 〈 0.05） or Aurora AASODN alone （P 〈 0.05）. Conclusion： Inhibition of Aurora A expression can result in the suppression of cell growth and chemosensitizing activity to paclitaxel in human lung cancer cell line A549.

Study of Pravastatin on Intervention of the Apoptosis in Human Lung Adenocarcinoma A549

Lung cancer is one of the serious threats to human health and life of malignant diseases, on a global scale; it has become one of the major lung cancer deaths. Due to the growth of the tumor and the main reason is that apoptosis is inhibited, therefore, it can induce apoptosis in lung cancer cells that is an important measure for the treatment of lung cancer, which is one of the effective means to reduce lung cancer mortality. In this paper, A549 human lung adenocarcinoma cell line, for example, has the use of chemical genetics of these emerging technological platforms, research pravastatin on apoptosis in human lung adenocarcinoma A549 intervention, while providing a theoretical basis for the development of new lung cancer therapy.

芝麻素对长春瑞滨诱导人肺腺癌A549细胞凋亡的影响

[目的]探讨芝麻素对长春瑞滨诱导人肺腺癌A549细胞株凋亡的影响.[方法]选择人肺腺癌A549细胞株进行体外传代培养,制备成浓度为1.0×105个/mL的细胞悬浮液并接种于96孔板中.实验设空白组(加入DMEM培养液)、对照组(加入DMEM培养液及人肺腺癌A549细胞株)、芝麻素组(芝麻素10、20、30、40、50、60、70、80、90、100μg/mL)、长春瑞滨组(长春瑞滨5、10、15、20、25、30、35μg/mL)及联合用药组(加入IC50浓度的芝麻素和长春瑞滨,IC50为后续联合用药组实验药物浓度).空白组加入160μL的DMEM培养液,对照组及实验组各加入160μL已制备好的人肺腺癌A549细胞株悬浮液,待细胞株贴壁后,空白组、对照组及实验组分别加入20μL的生理盐水和20μL各相关浓度的药物.采用MTT法检测细胞增殖能力,利用倒置显微镜及HE染色法观察细胞形态学变化,采用流式细胞仪检测细胞凋亡情况.[结果]在10~100μg/mL质量浓度范围内,低质量浓度的芝麻素具有抑制A549细胞株增殖的作用,IC50质量浓度为40μg/mL;在5~35μg/mL质量浓度范围内,长春瑞滨具有抑制A549细胞株增殖的作用,且随着药物质量浓度升高细胞抑制率升高,IC50质量浓度为20μg/mL;芝麻素与长春瑞滨联合用药对A549细胞株的抑制率明显高于单药用药(P<0.01).倒置显微镜及HE染色法观察结果显示,与对照组比较,芝麻素(40μg/mL)、长春瑞滨(20μg/mL)及联合用药(芝麻素40μg/mL+长春瑞滨20μg/mL)作用于A549细胞株48 h后贴壁细胞数量均明显减少,细胞间连接疏松,贴壁能力减弱,部分细胞体积变小、变圆或呈不规则形,核染色质凝集,细胞膜起泡形成凋亡小体,失去原有肿瘤细胞多角形或梭形形态,且联合用药组较单药组上述变化更为明显.流式细胞仪检测结果显示,药物作用48 h后,芝麻素组(40μg/mL)、长春瑞滨组(20μg/mL)及联合用药组(芝麻素40μg/mL+长春瑞滨20μg/mL)细胞凋亡率均明显高于对照组(P<0.01),且联合用药组早期凋亡率明显高于单独用药组(P<0.01).[结论]芝麻素可增强长春瑞滨诱导人肺腺癌A549细胞凋亡的作用.

The Inhibitory Effects of Rh-endostatin(YH-16) in Combination with Radiotherapy on Lung Adenocarcinoma A549 in Mice and the Underlying Mechanisms

In order to investigate the inhibitory effects of Endostar(rh-endostatin,YH-16)in combination with radiotherapy on lung adenocarcinoma A549 in mice and the interaction mechanisms of combined therapy,the transplantation tumor models of A549 lung adenocarcinoma were established.When the largest diameter of tumor reached 1.0cm,all nude mice were randomly divided into 4 groups:Endostar group,radiotherapy group,radiotherapy plus Endostar(combined treatment)group,and control group(n=6 in each group).The largest d...

miR-33a-5p靶基因分析验证及对人肺腺癌A549细胞增殖的影响

目的研究miR-33a-5p过表达对人肺腺癌A549细胞增殖的影响及探索其可能的机制。方法在A549细胞中瞬时转染miR-33a-5p mimics,CCK-8和BrdU实验检测细胞增殖能力,转录组测序(RNA-seq)检测mRNA表达水平,targetscan(8.0)、miRDB(2020)、miRWalk(release_2022_01)和ENCORI(starbase,v2.0)联合筛选miR-33a-5p的潜在靶基因,并与RNA-seq的下调表达的基因取交集,RT-qPCR进行基因表达验证。结果RT-qPCR结果显示,miR-33a-5p在A549细胞中高表达(P<0.05);CCK-8实验和BrdU实验结果显示,细胞增殖能力受到抑制(P均<0.05);RNA-seq结果显示,差异基因共494个,其中上调266个,下调228个;GO功能富集主要在细胞外区组成、质膜的组成、受体复合物、细胞外泌体、细胞外基质结构组成、钙离子结合等,KEGG富集主要在补体和凝血途径、胰岛素抵抗、ABC转运途径、IL-17途径、NOD样受体途径和NF-κB信号通路等;靶基因预测分析和RT-qPCR表达验证显示,MTHFD2、OSBPL6、HADHB、HMGCLL1、GUCY1A2和DEPTOR是miR-33a-5p的潜在靶基因(P均<0.05)。结论miR-33a-5p可能通过调控MTHFD2、OSBPL6、HADHB、HMGCLL1、GUCY1A2和DEPTOR基因转录后表达水平来抑制A549细胞的增殖。

Highly Efficient Labeling of Human Lung Cancer Cells Using Cationic Poly-L-lysine-Assisted Magnetic Iron Oxide Nanoparticles

Cell labeling with magnetic iron oxide nanoparticles(IONPs)is increasingly a routine approach in the cellbased cancer treatment.However,cell labeling with magnetic IONPs and their leading effects on the biological properties of human lung carcinoma cells remain scarcely reported.Therefore,in the present study the magnetic c-Fe2O3nanoparticles(MNPs)were firstly synthesized and surface-modified with cationic poly-L-lysine(PLL)to construct the PLL-MNPs,which were then used to magnetically label human A549 lung cancer cells.Cell viability and proliferation were evaluated with propidium iodide/fluorescein diacetate double staining and standard 3-(4,5-dimethylthiazol-2-diphenyl-tetrazolium)bromide assay,and the cytoskeleton was immunocytochemically stained.The cell cycle of the PLL-MNPlabeled A549 lung cancer cells was analyzed using flow cytometry.Apoptotic cells were fluorescently analyzed with nuclear-specific staining after the PLL-MNP labeling.The results showed that the constructed PLL-MNPs efficiently magnetically labeled A549 lung cancer cells and that,at low concentrations,labeling did not affect cellular viability,proliferation capability,cell cycle,and apoptosis.Furthermore,the cytoskeleton in the treated cells was detected intact in comparison with the untreated counterparts.However,the results also showed that at high concentration(400 lg m L-1),the PLL-MNPs would slightly impair cell viability,proliferation,cell cycle,and apoptosis and disrupt the cytoskeleton in the treated A549 lung cancer cells.Therefore,the present results indicated that the PLL-MNPs at adequate concentrations can be efficiently used for labeling A549 lung cancer cells and could be considered as a feasible approach for magnetic targeted anti-cancer drug/gene delivery,targeted diagnosis,and therapy in lung cancer treatment.

Up-Regulation of the Gap Junction Intercellular Communication by Tea Polyphenol in the Human Metastatie Lung Carcinoma Cell Line

Our previous study has proven that tea polyphenol has a role in lung neoplasms. The present communication was to investage the anti-proliferation effect of tea polyphenol on the PG cells, which was a high metastatic human lung carcinoma cell line, by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide (MTT) cell viability assay, and to study the change of intracellular calcium concentration, connexin43 (Cx43) expression, gap junctional intercellular communication (GJIC) and cell cycle distribution after the tea polyphenol treatment by laser scanning confocal microscopy and flow cytometry. The results showed that 1) tea polyphenol could kill the PG cells in a dose-depent manner via inhibiting the PG cell proliferation and blocking the PG cell cycle progression staying in G0/G1 phase and not transfering in S and G2/M phases to reduce the PG cell proliferation index;2) the increases of intracellular calcium concentration, GJIC and Cx43 expression were related with the tea polyphenol doses. The data suggested that tea polyphenol could inhibit the growth of PG cells, which mechanism was associated with the up-regulation of GJIC.

Effects of Spinach Powder Fat-Soluble Extract on Proliferation of Human Gastric Adenocarcinoma Cells

Four kinds of assays were used to study the effect of a fat-soluble extract of spinach powder (SPFE) on the proliferation of human gastric adenocareinoma cell line (SGC-7901) in vitro.These studies included: (Ⅰ) cell growth assay, (Ⅱ) colony forming assay, (Ⅲ) MTT colorimetric assay, and (Ⅳ) 3H-TdR incorporation assay. The concentrations of SPFE expressed as the level of β-carotene in the medium were 2×10-8, 2×10-7 and 2×10-6 mol/L β-carotene in assays (Ⅰ)～(Ⅲ), but 4×10- 8, 4×10-7 and 4×10-6 mol/L β-caretene in assay (Ⅳ) respectively. The results indicated that SPFE inhibited the prolifendion and colony forming ability of SGC-7901 cells. And in MTT assay, SPFE inhibited the viability of SGC7901 cells, but no inhibitory effect of SPFE was observed on the viability of lymphocytes in peripheral blood of healthy people. Finally, in the 3H-TdR incorporation test, both SPFE and β-carotene showed significant inhibitory effects on DNA synthesis in SGC-7901 cells, but SPFE was more effective than β-carotene.

EXPRESSION AND REVERSION OF DRUG RESISTANCE-AND APOPTOSIS-RELATED GENES OF A DDP-RESISTANT LUNG ADENOCARCINOMA CELL LINE

Objective: To investigate the co-expression of drug resistance- and apoptosis-related genes of cisplatin (CDDP)-selected lung adenocarcinoma cell line A 549 DDP for compared to the parental cell line A549, and reverse of drug resistance by antisense s-oligodeoxynucleotides (S-ODNs) of differentially expressed genes. Methods: Sense and antisense S-ODN were transferred into A 549 DDP cells by lipofectin. The expression of drug resistance and apoptosis related genes was examined by RT-PCR, immunocytochemistry and flow cytometry, respectively. Apoptostic cells were identified by DNA electrophoresis and terminal deoxynucleotidyl transferase (TdT)-mediated biotin dUTP nick end-labeling(TUNEL). Drug resistance of tumor cells was detected by a cell viability (MTT) assay. Results: The expression of bcl-2 was positive and that of multidrug resistance-associated protein (MRP) at mRNA and protein level was increased in A 549 DDP compared to A549 cells. MDR1, c-myc and topoisomeras II (TOPO II) were similarly co-expressed in two cell lines. Both cell lines were negative for c-erbB-2 expression. In A 549 DDP cells, the expression of bcl-2 and MRP was significantly inhibited by their respective antisense S-ODNs. Antisense S-ODNs could also decrease significantly drug resistance of A 549 DDP cells to CDDP by promoting cell apoptosis. Conclusion: Both intrinsic and acquired drug resistance were involved in co-expression of multiple MDR-related genes in lung adenocarcinoma. Cooperation of bcl-2 and MRP genes appeared to play an important action to confer the resistance of A 549 DDP cells to CDDP. Their antisense S-ODNs are responsible for the decrease of drug resistance of this cell line by promoting apoptosis.

Alterations and Its Mechanisms of Wnt Signal Pathway in Human High-matastatatic Large Cell Lung Cancer Cell Line L9981 by Transfecting with Nm23-H1 Gene

Backgroud and Objective Tumor metastasis is not only the malignant marker and characteristics of lung cancer, but also the main cause of failure to cure and lose their life of the

The Difference of the Copy Number Variation and Loss of Heterozygosity of Human Lung Large Cell Cancer Cell Line with Different Metastatic Potential

Background and Objective It has been proven that copy number gain/or loss (copy number variation CNV) in uences gene expression and result in phenotypic variation by

Effects of Methylseleninic Acid on the Proliferation and Cell Cycle in Human High Metastatic Large Cell Lung Cancer Cell Line L9981 and Its Molecular Mechanism

Background and Objective Lung cancer is the rst killer of human being in the whole world. Recently, although many treatment strategies have been developed, the anti-cancer effects