曲古霉素A增强肺癌细胞对放射线敏感性及机制

目的：探讨组蛋白去乙酰化酶抑制剂曲古霉素A（trichostatin A,TSA）增强人非小细胞肺癌（NscLc）A549对γ-射线敏感性作用及机制。方法：以TSA（0．51zM）预处理细胞18h,再以5Gyγ-射线照射细胞,24h后采用MTT法检测细胞存活率,AnnexinV—PI染色检测细胞凋亡,Westernblot法检测胞浆中和线粒体促凋亡蛋白Bax的表达,流式细胞仪检测细胞线粒体膜电位变化。结果-5Gyγ-射线照射可轻度降低细胞存活率,仅有少量细胞发生凋亡,以TSA预处理再以γ-射线处理细胞,细胞存活率显著下降,凋亡细胞明显增多,伴有线粒体膜电位下降,以及Bax蛋白的激活,表现在线粒体Bax表达较单纯照射组显著增高。结论：TSA通过促进Bax蛋白的活化激活线粒体凋亡途径,增强增强A549细胞对γ-射线的敏感性。     

肿瘤相关成纤维细胞对非小细胞肺癌恶性生物学行为影响

目的:探讨肿瘤相关成纤维细胞(Tancer Associated Fibroblast,TAF)对非小细胞肺癌(Non-small Cell Lung Cancer,NSCLC)恶性生物学行为的影响。方法:选取在本院肿瘤科住院手术的非小细胞肺癌患者,收集术后肺癌标本,马松三色染色(Masson Trichrome Stain)和天狼星红染色(Sirius Red Stain)观察肺癌组织(Lung Cancer Tissue,LCT)、癌旁组织(Pericarcinomatous Tissue,PCT)和正常组织(Normal Tissue,NT)中TAF的表达情况;体外将非小细胞肺癌细胞A549与非小细胞肺癌成纤维细胞P-gp共培养,CCK-8检测共培养前后A549细胞增殖能力;细胞划痕和Trans-well实验分别检测A549细胞迁移和侵袭能力;q RT-PCR和Western blot检测A549细胞上皮间质转化(Epithelial Mesenchymal Transition,EMT)标志蛋白E-cadherin、N-cadherin和Vimentin的表达。结果:Masson和Sirius染色结果显示:肺癌组织中纤维的表达明显高于癌旁组织;与P-gp共培养的A549细胞的增殖、迁移和侵袭能力及上皮间质转化相关蛋白N-cadherin和Vimentin表达均明显高于阴性对照组(P0.05),而E-cadherin的表达明显降低(P0.05)。结论:TAF可能通过诱导非小细胞肺癌细胞EMT的发生从而促进非小细胞肺癌的增殖、迁移和侵袭等恶性生物学行为。     

Nupr1调控非小细胞肺癌细胞迁移、凋亡机制的研究

目的:探讨核蛋白1(Nupr1)调控非小细胞肺癌细胞迁移、凋亡机制的研究。方法:肿瘤抑制剂盐酸素(salinomycin)不同时间处理非小细胞肺癌细胞A549后采用Western Blot法检测非小细胞肺癌细胞A549中Cleaved Caspase-3、Nupr1的蛋白表达;Transwell小室检测Nupr1基因沉默后非小细胞肺癌细胞A549细胞体外迁移、侵袭能力的变化;Western Blot法检测Nupr1沉默后非小细胞肺癌细胞A549 MMP-2、TIMP-1的蛋白表达;流式细胞仪检测Nupr1沉默后非小细胞肺癌细胞A549的凋亡情况。结果:与未经肿瘤抑制剂salinomycin处理对照组相比较,salinomycin处理后的非小细胞肺癌细胞A549中Nupr1蛋白表达量下降,Cleaved Caspase-3蛋白表达量升高,并且随着作用时间呈依赖关系。Nupr1-siRNA转染组的迁移能力相比对照组未转染组下降(64.4±7.2)%,Nupr1-siRNA转染组的侵袭能力相比对照组下降(58.7±7.3)%。与未转染Nupr1-siRNA对照组相比较,转染后TIMP-1的表达明显上调,而MMP-2的表达则明显下调。流式细胞仪检测结果显示Nupr1沉默后非小细胞肺癌细胞A549出现大量凋亡。结论:Nupr1基因沉默后通过上调TIMP-1的表达,下调MMP-2的表达降低肺癌A549细胞的侵袭和迁移能力,进而促进非小细胞肺癌细胞凋亡。     

内吞适配蛋白Epsin在非小细胞肺癌发生中的作用研究

目的:探讨内吞适配蛋白Epsin在非小细胞肺癌发生中的潜在作用。方法:选择体外培养的人非小细胞肺癌细胞(A549),筛选Epsin 1和Epsin 2 shRNA干扰效率达标的细胞。将裸鼠随机分为3组,每组10只,第1、2组裸鼠分别经胸腔植入人非小细胞肺癌细胞(A549)及epsin表达敲减的A549细胞,第3组注射等量的生理盐水,比较1、2组小鼠肿瘤体积的变化。8周后,处死所有裸鼠,留取肺组织及肿瘤组织,通过免疫荧光染色检测非肿瘤(正常)肺和致瘤性肺组织中的epsin 1和2的蛋白质水平。用实时定量PCR(qRT-PCR)来研究epsin 1和2的基因表达水平。结果:肺肿瘤组织epsin1和2的m RNA和蛋白表达均显著高于正常肺组织中(P0.05)。种植epsin表达敲减的A549细胞裸鼠肿瘤生长速度及体积均大于种植正常A549细胞的裸鼠肿瘤。结论:Epsins表达上调可能促进非小细胞肺癌肿瘤的发生发展,而敲减epsins的表达可能为未来的非小细胞肺癌的治疗提供新的治疗靶点。     

KIF26B在非小细胞肺癌发生发展过程中的表达与功能研究

驱动蛋白与肿瘤的发生有密切联系，但对 KIF26B驱动蛋白在非小细胞肺癌的表达和相关功能作用的研究甚少。为了探索KIF26B在非小细胞肺癌中的表达水平及潜在机制，通过干扰KIF26B后探索对非小细胞肺癌增殖、侵袭、迁移、细胞周期、凋亡以及相关蛋白表达量的影响。对mRNA TCGA 数据库信息分析得出，KIF26B基因在非小细胞肺癌中高表达。qRT-PCR 检测 KIF26B在几株常见非小细胞肺癌细胞系中的表达水平，筛选出 KIF26B在A549 和 NCI-H292细胞系中高表达。利用 RNA干扰技术(RNA interference, RNAi)敲低 A549 和 NCI-H292细胞的 KIF26B基因，通过CCK8、采用实时细胞分析仪、平板克隆及 Transwell 实验检测敲低 KIF26B基因后的生物学功能，免疫印迹法检测蛋白表达水平。结果显示，敲低KIF26B后A549 和 NCI-H292细胞增殖明显降低，侵袭及迁移能力明显减弱。敲低KIF26B后阻碍了A549 和 NCI-H292细胞从G1期向S期的转变，同时凋亡细胞明显增多，与之相关的细胞周期蛋白 D1、Bcl-2、E-cadherin和Vimentin的表达水平显著下调，同时活化的半胱天冬酶-3（active Caspase-3）和其剪切底物 PARP1 的剪切体（cleaved PARP1）表达水平显著上调。结果表明KIF26B可能作为非小细胞肺癌发生的促癌基因，参与了非小细胞肺癌的发生及发展过程。KIF26B有望成为非小细胞肺癌治疗的潜在靶点。     

RHCG基因在非小细胞肺癌中的表达及对细胞增殖的影响

为了探讨Rh type C glycoprotein (RHCG)对非小细胞肺癌(non-small cell lung cancer,NSCLC)细胞增殖的影响及可能的作用机制,本研究使用荧光定量PCR法检测12对NSCLC及癌旁组织样本中RHCG mRNA的表达水平及pcDNA3.1-RHCG质粒对A549细胞RHCG m RNA的表达;采用CCK-8法检测细胞增殖能力;运用PI染色法检测细胞周期;使用免疫印迹法检p-PI3K、PI3K、p-AKT以及AKT蛋白表达水平。本研究发现,与癌旁组织比较,NSCLC中RHCG m RNA表达水平明显降低。RHCG过表达能抑制NSCLC细胞系A549细胞增殖能力。此外,RHCG过表达使A549细胞周期G1/S期转化发生阻滞。本研究还发现,RHCG过表达可下调A549细胞p-PI3K/PI3K和p-AKT/AKT水平。本研究表明,RHCG抑制NSCLC细胞增殖的作用与其抑制PI3K/AKT信号通路有关。     

ITGB1 enhances the Radioresistance of human Non-small Cell Lung Cancer Cells by modulating the DNA damage response and YAP1-induced Epithelial-mesenchymal Transition

Objectives: Radiotherapy has played a limited role in the treatment of non-small cell lung cancer (NSCLC) due to the risk of tumour radioresistance. We previously established the radioresistant non-small cell lung cancer (NSCLC) cell line H460R. In this study, we identified differentially expressed genes between these radioresistant H460R cells and their radiosensitive parent line. We further evaluated the role of a differentially expressed gene, ITGB1, in NSCLC cell radioresistance and as a potential target for improving radiosensitivity.Materials and Methods: The radiosensitivity of NSCLC cells was evaluated by flow cytometry, colony formation assays, immunofluorescence, and Western blotting. Bioinformatics assay was used to identify the effect of ITGB1 and YAP1 expression in NSCLC tissues.Results: ITGB1 mRNA and protein expression levels were higher in H460R than in the parental H460 cells. We observed lower clonogenic survival and cell viability and a higher rate of apoptosis of ITGB1-knockdown A549 and H460R cells than of wild type cells post-irradiation. Transfection with an ITGB1 short hairpin (sh) RNA enhanced radiation-induced DNA damage and G2/M phase arrest. Moreover, ITGB1 induced epithelial-mesenchymal transition (EMT) of NSCLC cells. Silencing ITGB1 suppressed the expression and intracellular translocation of Yes-associated protein 1 (YAP1), a downstream effector of ITGB1.Conclusions: ITGB1 may induce radioresistance via affecting DNA repair and YAP1-induced EMT. Taken together, our data suggest that ITGB1 is an attractive therapeutic target to overcome NSCLC cell radioresistance.     

内毒素诱导非小细胞肺癌细胞增殖及其机制

目的：研究内毒素对体外培养非小细胞肺癌（NSCLC）细胞株A549细胞增殖的影响及其机制。方法：不同浓度脂多糖（LPS）进行8-48h干预,MTT及细胞计数法检测其对A549细胞增殖的影响;EGFR中和抗体或COX．2抑制剂与LPS联合干预,检测其对A549细胞增殖及PGE2的影响。结果iLPS可引发A549细胞MTT活性和细胞计数显著增加,且呈现时间和剂量依赖性。LPS还可诱发PGE2水平显著升高。药物干预结果显示,抑制COX-2或EGFR可明显逆转LPS所引发的细胞增殖和PGE2水平升高趋势。结论：LPS可能通过激活EGFR和COX-2信号途径,诱导体外培养的非小细胞肺癌细胞增殖分化。肺部感染可能会加速非小细胞肺癌进展,并可能造成不良预后。     

内毒素诱导非小细胞肺癌细胞增殖及其机制 李

摘要目的：研究内毒素对体外培养非小细胞肺癌（NSCLC）细胞株A549 细胞增殖的影响及其机制。方法：不同浓度脂多糖（LPS） 进行8-48h 干预,MTT 及细胞计数法检测其对A549 细胞增殖的影响;EGFR中和抗体或COX-2 抑制剂与LPS联合干预,检测其 对A549 细胞增殖及PGE2 的影响。结果：LPS 可引发A549 细胞MTT 活性和细胞计数显著增加,且呈现时间和剂量依赖性。LPS 还可诱发PGE2 水平显著升高。药物干预结果显示,抑制COX-2 或EGFR 可明显逆转LPS 所引发的细胞增殖和PGE2 水平升高 趋势。结论：LPS 可能通过激活EGFR 和COX-2 信号途径,诱导体外培养的非小细胞肺癌细胞增殖分化。肺部感染可能会加速非 小细胞肺癌进展,并可能造成不良预后。     

Dendritic cells efficiently acquire and present antigen derived from lung cancer cells and induce antigen-specific T-cell responses

Active immunotherapy of cancer requires the availability of a source of tumor antigens. To date, no such antigen associated with lung cancer has been identified. We have therefore investigated the ability of dendritic cells (DC) to capture whole irradiated human lung tumor cells and to present a defined surrogate antigen derived from the ingested tumor cells. We also describe an in vitro system using a modified human adenocarcinoma cell line (A549-M1) that expresses the well-characterized, immunogenic influenza M1 matrix protein as a surrogate tumor antigen. Peripheral blood monocyte-derived DC, when co-cultured with sub-lethally irradiated A549 cells or primary lung tumor cells derived from surgical resection of non-small cell carcinoma (NSCLC), efficiently ingested the tumor cells as determined by flow cytometry analysis and confocal microscopic examination. More importantly, DC loaded with irradiated A549-M1 cells efficiently processed and presented tumor cell-derived M1 antigen to T cells and elicited antigen-specific immune responses that included IFNgamma release from an M1-specific T-cell line, expansion of M1 peptide-specific Vbeta17+ and CD8+ peripheral T cells and generation of M1-specific cytotoxic T lymphocytes (CTL). We also compared DC loaded with irradiated tumor cells to those loaded with tumor cell lysate or killed tumor cells and found that irradiated lung tumor cells as a source of tumor antigen for DC loading is superior to tumor cell lysate or killed tumor cells in efficient induction of antigen-specific T-cell responses. Our results demonstrate the feasibility of using lung tumor cell-loaded DC to induce immune responses against lung cancer-associated antigens and support ongoing efforts to develop a DC-based lung cancer vaccine.     

MicroRNA-193b modulates proliferation, migration, and invasion of non-small cell lung cancer cells

MicroRNAs have been reported to be closely related to the development of human lung cancers. However, the functions of microRNAs in non-small cell lung cancer (NSCLC) remain largely undefined. Here, we investigated the role of microRNA-193b (miR-193b) in NSCLC. Our data showed that miR-193b was markedly down-regulated in NSCLC cancer tissues compared with adjacent normal tissues. The NSCLC cell line (A549) transfected with the miR-193b exhibited significantly decreased proliferation, migration, and invasion capacities when compared with the control cells. In contrast, inhibition of miR-193b increased the proliferation, migration, and invasion of A549 cells. Moreover, miR-193b repressed the expressions of cyclin D1 and urokinase-type plasminogen activator in A549 cells. These data suggest that miR-193b is a tumor suppressor in NSCLC.     

Involvement of TRPC Channels in Lung Cancer Cell Differentiation and the Correlation Analysis in Human Non-Small Cell Lung Cancer

The canonical transient receptor potential (TRPC) channels are Ca²⁺-permeable cationic channels controlling the Ca²⁺ influx evoked by G protein-coupled receptor activation and/or by Ca²⁺ store depletion. Here we investigate the involvement of TRPCs in the cell differentiation of lung cancer. The expression of TRPCs and the correlation to cancer differentiation grade in non-small cell lung cancer (NSCLC) were analyzed by real-time PCR and immunostaining using tissue microarrays from 28 patient lung cancer samples. The association of TRPCs with cell differentiation was also investigated in the lung cancer cell line A549 by PCR and Western blotting. The channel activity was monitored by Ca²⁺ imaging and patch recording after treatment with all-trans-retinoic acid (ATRA). The expression of TRPC1, 3, 4 and 6 was correlated to the differentiation grade of NSCLC in patients, but there was no correlation to age, sex, smoking history and lung cancer cell type. ATRA upregulated TRPC3, TRPC4 and TRPC6 expression and enhanced Ca²⁺ influx in A549 cells, however, ATRA showed no direct effect on TRPC channels. Inhibition of TRPC channels by pore-blocking antibodies decreased the cell mitosis, which was counteracted by chronic treatment with ATRA. Blockade of TRPC channels inhibited A549 cell proliferation, while overexpression of TRPCs increased the proliferation. We conclude that TRPC expression correlates to lung cancer differentiation. TRPCs mediate the pharmacological effect of ATRA and play important roles in regulating lung cancer cell differentiation and proliferation, which gives a new understanding of lung cancer biology and potential anti-cancer therapy.     

Down-Regulation of Canonical and Up-Regulation of Non-Canonical Wnt Signalling in the Carcinogenic Process of Squamous Cell Lung Carcinoma

The majority of lung cancers (LC) belong to the non-small cell lung carcinoma (NSCLC) type. The two main NSCLC sub-types, namely adenocarcinoma (AC) and squamous cell carcinoma (SCC), respond differently to therapy. Whereas the link between cigarette smoke and lung cancer risk is well established, the relevance of non-canonical Wnt pathway up-regulation detected in SCC remains poorly understood. The present study was undertaken to investigate further the molecular events in canonical and non-canonical Wnt signalling during SCC development. A total of 20 SCC and AC samples with matched non-cancerous controls were obtained after surgery. TaqMan array analysis confirmed up-regulation of non-canonical Wnt5a and Wnt11 and identified down-regulation of canonical Wnt signalling in SCC samples. The molecular changes were tested in primary small airway epithelial cells (SAEC) and various lung cancer cell lines (e.g. A549, H157, etc). Our studies identified Wnt11 and Wnt5a as regulators of cadherin expression and potentiated relocation of β-catenin to the nucleus as an important step in decreased cellular adhesion. The presented data identifies additional details in the regulation of SCC that can aid identification of therapeutic drug targets in the future.     

过表达Snail增强肺癌细胞A549的体外侵袭能力

用锌指转录因子Snail诱导肺癌细胞A549发生上皮细胞-间质转化(epithelial-mesenchymal transition,EMT),检测肺癌发生EMT后细胞侵袭能力的变化,为临床筛选分子靶向药物提供依据.构建pcDNA3.1-snail载体,用pcDNA3.1-snail及空pcDNA3.1载体转染肺癌A549细胞后,进行G418筛选;光镜观察培养后细胞形态学的改变、免疫细胞化学与免疫荧光检测细胞表达E-钙黏着蛋白(E-cadherin)、波形蛋白(vimentin)的改变,Western印迹检测细胞中E-钙黏着蛋白和波形蛋白的改变,Transwell侵袭小室法进行细胞体外侵袭能力检测.采用pcDNA3.1-snail转染细胞后,A549细胞变得细长,细胞融合度降低.免疫细胞化学、免疫荧光、Western印迹结果显示,E-钙黏着蛋白表达降低,波形蛋白表达升高;transwell侵袭小室法结果显示,过表达Snail的A549细胞穿透matrigel胶的细胞数明显增多.结果提示,Snail能有效诱导肺癌发生EMT,并且能增强肺癌的体外侵袭能力.     

MicroRNA-575靶向抑制BLID促进非小细胞肺癌细胞的增殖和侵袭

目的:通过体外实验探讨miR-575对非小细胞肺癌(NSCLC)细胞增殖与侵袭能力的影响及相关机制。方法:采用实时定量PCR法检测不同非小细胞肺癌细胞系中miR-575、BLID的表达;CCK-8法检测转染miR-575模拟物、抑制因子后不同时间A549细胞增殖情况的变化;Transwell法检测A549细胞的侵袭情况;Targetcan法及双荧光素酶检测miR-575对BLID 3'UTR端的靶向作用;Western blot法检测BLID蛋白的表达。结果:A549、SPC-A1、H1299、H1650等人非小细胞肺癌细胞系中miR-575的表达均显著高于永生化的人支气管上皮细胞系16HBE(P0.001)。MiR-575模拟物转染的A549细胞miR-575的表达明显高于对照组(P0.001),同时细胞的增殖和侵袭力增强(P0.05);反之,miR-575抑制因子转染的A549细胞miR-575的表达显著降低,且细胞的增殖和侵袭力明显降低(P0.01)。Targetscan法预测BLID可能是miR-575的下游靶基因,荧光素酶结果显示miR-575不仅能够有效抑制野生型BLID 3'UTR端的荧光素酶反应(P0.01),而且能够降低BLID的蛋白表达量(P0.01)。实时定量PCR结果显示BLID在NSCLC细胞系中均呈现显著的低表达(P0.001),且转染BLID后,NSCLC细胞的增殖和细胞侵袭被明显抑制(P0.05),而当miR-575与BLID共转染时,miR-575能够逆转BLID所抑制的细胞增殖和侵袭(P0.01)。结论:在NSCLC细胞系中,miR-575的表达上调,且能够通过直接作用于下游靶点抑癌基因BLID从而促非小细胞肺癌细胞增殖及侵袭。     

融合细胞株Eahy926与亲本人肺腺癌细胞株A549差异表达蛋白的蛋白质组学分析

融合细胞株Eahy926是人肺腺癌细胞株A549和人脐静脉内皮细胞杂交而成的永生化细胞株,具有血管内皮细胞的特性,已广泛用于内皮细胞相关研究. 本研究应用蛋白质组学技术分析融合细胞株Eahy926与亲本人肺腺癌细胞株A549的蛋白质差异表达,探讨融合细胞生物学特性变化及其机制. 对Eahy926和亲本A549的细胞总蛋白质进行双向凝胶电泳,在PDQuest软件辅助下找出差异表达蛋白质点,经肽质量指纹图谱(peptide mass fingerprinting, PMF) 和串级质谱(tandem mass spectrometry,TMS) 分析,SWISS-PROT数据库检索,成功鉴定出28个差异蛋白,如CATB、CK8、CK18、annexin A2、GRP78、HSP90、HSP60、vimentin等一些与分子伴侣、氧化应激、能量代谢、信号转导等有关,并与肿瘤细胞分裂增殖、分化凋亡、侵袭转移、免疫逃逸以及肿瘤血管生长密切关联的蛋白质. 研究发现,融合细胞株Eahy926和人肺腺癌细胞株A549的蛋白质组表达谱存在明显差异,这将有助于今后进一步探讨肿瘤细胞与内皮细胞的相互作用机制及其融合细胞的特性,筛选肿瘤增殖和转移相关蛋白质及分子标志物,亦可为肿瘤的抗血管生成治疗提供新思路.     

PAK1 Kinase Promotes Cell Motility and Invasiveness through CRK-II Serine Phosphorylation in Non-Small Cell Lung Cancer Cells

The role of c-Crk (CRK) in promoting metastasis is well described however the role of CRK phosphorylation and the corresponding signaling events are not well explained. We have observed CRK-II serine 41 phosphorylation is inversely correlated with p120-catenin and E-cadherin expressions in non-small cell lung cancer (NSCLC) cells. Therefore, we investigated the role of CRK-II serine 41 phosphorylation in the down-regulation of p120-catenin, cell motility and cell invasiveness in NSCLC cells. For this purpose, we expressed phosphomimetic and phosphodeficient CRK-II serine 41 mutants in NSCLC cells. NSCLC cells expressing phosphomimetic CRK-II seine 41 mutant showed lower p120-catenin level while CRK-II seine 41 phosphodeficient mutant expression resulted in higher p120-catenin. In addition, A549 cells expressing CRK-II serine 41 phosphomimetic mutant demonstrated more aggressive behavior in wound healing and invasion assays and, on the contrary, expression of phosphodeficient CRK-II serine 41 mutant in A549 cells resulted in reduced cell motility and invasiveness. We also provide evidence that PAK1 mediates CRK-II serine 41 phosphorylation. RNAi mediated silencing of PAK1 increased p120-catenin level in A549 and H157 cells. Furthermore, PAK1 silencing decreased cell motility and invasiveness in A549 cells. These effects were abrogated in A549 cells expressing phosphomimetic CRK-II serine 41. In summary, these data provide evidence for the role of PAK1 in the promotion of cell motility, cell invasiveness and the down regulation of p120-catenin through CRK serine 41 phosphorylation in NSCLC cells.     

MicroRNA-567 inhibits cell proliferation and induces cell apoptosis in A549 NSCLC cells by regulating cyclin-dependent kinase 8

MicroRNA-567 (miR-567) plays a decisive role in cancers whereas its role in non-small cell lung cancer (NSCLC) is still unexplored. This study was therefore planned to explore the regulatory function of miR-567 in A549 NSCLC cells and investigate its possible molecular mechanism that may help in NSCLC treatment. In the current study, miR-567 expression was examined by quantitative real time-polymerase chain reaction (qRT-PCR) in different NSCLC cell lines in addition to normal cell line. A549 NSCLC cells were transfected by miR-567 mimic, miR-567 inhibitor, and negative control siRNA. Cell proliferation was evaluated by MTT and 5-bromo-2′deoxyuridine assays. Cell cycle distribution and apoptosis were studied by flow cytometry. Bioinformatics analysis programs were used to expect the putative target of miR-567. The expression of cyclin-dependent kinase 8 (CDK8) gene at mRNA and protein levels were evaluated by using qRT-PCR and western blotting. Our results found that miR-567 expressions decreased in all the studied NSCLC cells as compared to the normal cell line. A549 cell proliferation was suppressed by miR-567 upregulation while cell apoptosis was promoted. Also, miR-567 upregulation induced cell cycle arrest at sub-G1 and S phases. CDK8 was expected as a target gene of miR-567. MiR-567 upregulation decreased CDK8 mRNA and protein expression while the downregulation of miR-567 increased CDK8 gene expression. These findings revealed that miR-567 may be a tumor suppressor in A549 NSCLC cells through regulating CDK8 gene expression and may serve as a novel therapeutic target for NSCLC treatment.     

Induction of Cell Cycle Arrest and Apoptosis by Ruthenium Complex cis-(Dichloro)tetramineruthenium(III) Chloride in Human Lung Carcinoma Cells A549

Lung cancer is one of the leading causes of death in the world, and non-small cell lung carcinoma (NSCLC) accounts for approximately 75-85% of all lung cancers. In the present work, we studied the cytotoxic activity, cell cycle arrest and induction apoptosis of the compound cis-(dichloro)tetramineruthenium(III) chloride {cis-[RuCl(2)(NH(3))(4)]Cl} in human lung carcinoma tumor cell line A549. The results of MTT and trypan blue assays showed that cis-[RuCl(2)(NH(3))(4)]Cl causes reduction in the viability of A549 cells when treating with 95 and 383 μM of the compound for 48 and 72 h. Lower concentrations of the compound (19, 3.8 and 0.38 μM), however, only slightly affected cell viability. The IC(50) value for the compound was about 383 μM. Survival analysis of the A549 cells after treatment with ruthenium(III) compound using long term clonogenic assay showed that it reduced colony formation ability at concentrations of 0.38 and 3.8 μM, and at concentrations of 95 and 383 μM no colonies were observed. Cell cycle analysis showed that compound ruthenium led to an accumulation of A549 cells in S phase and increased in the sub-G1 peak. In addition, cis-(dichloro)tetramineruthenium(III) chloride treatment induced apoptosis, as observed by the increased numbers of annexin V-positive cells and increased messenger RNA expression of caspase-3.     

Dihydroartemisinin Inhibits Glucose Uptake and Cooperates with Glycolysis Inhibitor to Induce Apoptosis in Non-Small Cell Lung Carcinoma Cells

Despite recent advances in the therapy of non-small cell lung cancer (NSCLC), the chemotherapy efficacy against NSCLC is still unsatisfactory. Previous studies show the herbal antimalarial drug dihydroartemisinin (DHA) displays cytotoxic to multiple human tumors. Here, we showed that DHA decreased cell viability and colony formation, induced apoptosis in A549 and PC-9 cells. Additionally, we first revealed DHA inhibited glucose uptake in NSCLC cells. Moreover, glycolytic metabolism was attenuated by DHA, including inhibition of ATP and lactate production. Consequently, we demonstrated that the phosphorylated forms of both S6 ribosomal protein and mechanistic target of rapamycin (mTOR), and GLUT1 levels were abrogated by DHA treatment in NSCLC cells. Furthermore, the upregulation of mTOR activation by high expressed Rheb increased the level of glycolytic metabolism and cell viability inhibited by DHA. These results suggested that DHA-suppressed glycolytic metabolism might be associated with mTOR activation and GLUT1 expression. Besides, we showed GLUT1 overexpression significantly attenuated DHA-triggered NSCLC cells apoptosis. Notably, DHA synergized with 2-Deoxy-D-glucose (2DG, a glycolysis inhibitor) to reduce cell viability and increase cell apoptosis in A549 and PC-9 cells. However, the combination of the two compounds displayed minimal toxicity to WI-38 cells, a normal lung fibroblast cell line. More importantly, 2DG synergistically potentiated DHA-induced activation of caspase-9, -8 and -3, as well as the levels of both cytochrome c and AIF of cytoplasm. However, 2DG failed to increase the reactive oxygen species (ROS) levels elicited by DHA. Overall, the data shown above indicated DHA plus 2DG induced apoptosis was involved in both extrinsic and intrinsic apoptosis pathways in NSCLC cells.