Metastatic Lung Cancer Cell Line Research Articles

Epigenetic upregulation of spleen tyrosine kinase in cancer cells through p53-dependent downregulation of DNA methyltransferase

Syk is a tumor suppressor gene in some solid tumors. Currently, it remains unknown how Syk gene hypermethylation is controlled by DNA methyltransferase (DNMT) and p53. In colorectal cancer HCT116 cells, we found that protein and mRNA levels of Syk were much higher in WT than in p53−/− cells. Both p53 inhibitor PFT-α and p53 silencing can reduce the protein and mRNA expression of Syk in WT cells, while DNMT inhibitor 5-Aza-2′-dC can increase Syk expression in p53−/− cells. Interestingly, the DNMT expression in p53−/− HCT116 cells was higher than that in WT cells. PFT-α can not only enhance Syk gene methylation but also increase DNMT1 protein and mRNA levels in WT HCT116 cells. In metastatic lung cancer cell lines A549 and PC9, which express WT p53 and gain function of p53, respectively, PFT-α can also downregulate Syk mRNA and protein expression. However, the Syk methylation level was increased by PFT-α in A549 but not in PC9 cells. Likewise, 5-Aza-2′-dC transcriptionally increased Syk gene expression in A549 cells, but not in PC9 cells. In summary methylation of Syk promoter requires DNMT1, and p53 can upregulate Syk expression via downregulation of DNMT1 at the transcriptional level.

A Screening of Epigenetic Therapeutic Targets for Non-Small Cell Lung Cancer Reveals PADI4 and KDM6B as Promising Candidates.

Despite advances in diagnostic and therapeutic approaches for lung cancer, new therapies targeting metastasis by the specific regulation of cancer genes are needed. In this study, we screened a small library of epigenetic inhibitors in non-small-cell lung cancer (NSCLC) cell lines and evaluated 38 epigenetic targets for their potential role in metastatic NSCLC. The potential candidates were ranked by a streamlined approach using in silico and in vitro experiments based on publicly available databases and evaluated by real-time qPCR target gene expression, cell viability and invasion assays, and transcriptomic analysis. The survival rate of patients with lung adenocarcinoma is inversely correlated with the gene expression of eight epigenetic targets, and a systematic review of the literature confirmed that four of them have already been identified as targets for the treatment of NSCLC. Using nontoxic doses of the remaining inhibitors, KDM6B and PADI4 were identified as potential targets affecting the invasion and migration of metastatic lung cancer cell lines. Transcriptomic analysis of KDM6B and PADI4 treated cells showed altered expression of important genes related to the metastatic process. In conclusion, we showed that KDM6B and PADI4 are promising targets for inhibiting the metastasis of lung adenocarcinoma cancer cells.

Cathepsin F and Fibulin-1 as novel diagnostic biomarkers for brain metastasis of non-small cell lung cancer

BackgroundThe lack of non-invasive methods for detection of early micro-metastasis is a major cause of the poor prognosis of non-small cell lung cancer (NSCLC) brain metastasis (BM) patients. Herein, we aimed to identify circulating biomarkers based on proteomics for the early diagnosis and monitoring of patients with NSCLC BM.MethodsUpregulated proteins were detected by secretory proteomics in the animal-derived high brain metastatic lung cancer cell line. A well-designed study composed of three independent cohorts was then performed to verify these blood-based protein biomarkers: the serum discovery and verification cohorts (n = 80; n = 459), and the tissue verification cohort (n = 76). Logistic regression was used to develop a diagnostic biomarker panel. Model validation cohort (n = 160) was used to verify the stability of the constructed predictive model. Changes in serum Cathepsin F (CTSF) levels of patients were tracked to monitor the treatment response. Progression-free survival (PFS) and overall survival (OS) were analysed to assess their prognostic relevance.ResultsCTSF and Fibulin-1 (FBLN1) levels were specifically upregulated in sera and tissues of patients with NSCLC BM compared with NSCLC without BM and primary brain tumour. The combined diagnostic performance of CTSF and FBLN1 was superior to their individual ones. CTSF serum changes were found to reflect the therapeutic response of patients with NSCLC BM and the trends of progression were detected earlier than the magnetic resonance imaging changes. Elevated expression of CTSF in NSCLC BM tissues was associated with poor PFS, and was found to be an independent prognostic factor.ConclusionsWe report a novel blood-based biomarker panel for early diagnosis, monitoring of therapeutic response, and prognostic evaluation of patients with NSCLC BM.

ENO1 Promotes Lung Cancer Metastasis via HGFR and WNT Signaling-Driven Epithelial-to-Mesenchymal Transition.

ENO1 (α-enolase) expression is significantly correlated with reduced survival and poor prognosis in many cancer types, including lung cancer. However, the function of ENO1 in carcinogenesis remains elusive. In this study, we found that high expression of ENO1 is present in metastatic lung cancer cell lines and malignant tumors and is associated with poor overall survival of patients with lung cancer. Knockdown of ENO1 decreased cancer cell proliferation and invasiveness, whereas overexpression of ENO1 enhanced these processes. Moreover, ENO1 expression promoted tumor growth in orthotopic models and enhanced lung tumor metastasis in tail-vein injection models. These effects were mediated by upregulation of mesenchymal markers N-cadherin and vimentin and the epithelial-to-mesenchymal transition regulator SLUG, along with concurrent downregulation of E-cadherin. Mechanistically, ENO1 interacted with hepatocyte growth factor receptor (HGFR) and activated HGFR and Wnt signaling via increased phosphorylation of HGFR and the Wnt coreceptor LRP5/6. Activation of these signaling axes decreased GSK3β activity via Src-PI3K-AKT signaling and inactivation of the β-catenin destruction complex to ultimately upregulate SLUG and β-catenin. In addition, we generated a chimeric anti-ENO1 mAb (chENO1-22) that can decrease cancer cell proliferation and invasion. chENO1-22 attenuated cancer cell invasion by inhibiting ENO1-mediated GSK3β inactivation to promote SLUG protein ubiquitination and degradation. Moreover, chENO1-22 prevented lung tumor metastasis and prolonged survival in animal models. Taken together, these findings illuminate the molecular mechanisms underlying the function of ENO1 in lung cancer metastasis and support the therapeutic potential of a novel antibody targeting ENO1 for treating lung cancer. SIGNIFICANCE: This study shows that ENO1 promotes lung cancer metastasis via HGFR and WNT signaling and introduces a novel anti-ENO1 antibody for potential therapeutic use in lung cancer.

Affinity chromatography based phosphoproteome research on lung cancer cells and its application

磷酸化是蛋白质翻译后修饰的重要形式之一,其异常往往会导致细胞内信号通路的紊乱和疾病的发生。固定化金属离子亲和色谱(IMAC)是磷酸化肽段的高效富集技术,在磷酸化蛋白质组研究方面应用广泛。该研究以金属钛离子(Ti4+)螯合IMAC材料(Ti4+-IMAC)为载体,进行磷酸化肽段富集。比较了10 μm Ti4+-IMAC通过振荡法和固相萃取法(SPE)富集磷酸肽的效果,发现振荡法可以富集到更多的磷酸肽;对比了两种尺寸(10 μm和30 μm)Ti4+-IMAC在磷酸化肽段富集中的差异,发现小尺寸材料富集效果更佳。进一步采用优化的策略比较了不同转移能力肺癌细胞的磷酸化蛋白质组,免标记定量蛋白质组学结果表明,优化的Ti4+-IMAC方法可以从正常的肺成纤维细胞MRC5、低转移肺癌细胞95C和高转移肺癌细胞95D中分别鉴定到510、863和1108种磷酸化蛋白质,其中317种为3组所共有。该研究共鉴定到1268种磷酸化蛋白质上的7560个磷酸化位点,其中1130个为差异磷酸化位点,文献报道显示部分异常表达的激酶与癌症转移密切相关。通过生信对比分析发现,异常表达的磷酸化蛋白质主要与细胞侵袭、迁移和死亡等细胞迁移方面的功能有关。通过优化磷酸化肽富集策略,初步阐明了磷酸化蛋白质网络的异常与肺癌转移之间的相关性,该方法有望用于肺癌进展相关的磷酸化位点、磷酸化蛋白质及其信号通路研究。

Inhibition of metastasis and suppression of pERK1/2 and pFAK expression by Solanum xanthocarpum crude extracts in human lung cancer cell line A549 in vitro

Solanum xanthocarpum is an important part of natural remedies for lung in Ayurveda. Lung cancer metastasis is a major challenge in the present time. Expressions and activation of focal adhesion kinase (FAK) and extracellular receptor kinases 1 and 2 (ERK1/2) are key checkpoints in cancer which lead to an invasion, epithelial-mesenchymal transition (EMT) and metastatic progression. In this study, the efficacy of the whole plant and root crude extracts prepared in ethyl acetate and chloroform on highly metastatic lung cancer cell line A549 was evaluated. The effect of crude extracts on cell migration was scrutinized using transwell migration assessment. The phosphorylated forms of proteins, pFAK and pERK1/2 levels, were estimated using ELISA. Zymography technique was utilized to evaluate the activities of MMP-2 and MMP-9 proteins. The EMT markers, vimentin and N-cadherin gene expressions were analyzed using semi-quantitative RT-PCR. The extracts significantly reduced single-cell migration. The expression levels of pFAK and pERK1/2 notably decreased and FAK and ERK1/2 remained unchanged. Moreover, gelatinase activity, vimentin and N-cadherin expression were also significantly reduced in treated cells compared to untreated cells. The crude extracts of S. xanthocarpum impaired the metastatic progression of A549 cells in vitro.

LncRNA TM4SF1-AS1 Activates the PI3K/AKT Signaling Pathway and Promotes the Migration and Invasion of Lung Cancer Cells.

PurposeMetastasis is a crucial cause of the high mortality in patients with lung cancer. Long non-coding RNAs (lncRNAs) are emerging as important players in the development and progression of human cancers. Here, we aimed to identify metastasis-associated lncRNA and to study its roles in the migration and invasion of lung cancer cells.Materials and MethodsWe screened differentially expressed lncRNAs between high- and low-metastatic lung cancer cell lines by using microarray and identified the target lncRNA TM4SF1-AS1. The effect of the TM4SF1-AS1 on the invasion and migration was evaluated through the wound healing experiment and transwell assay. The expression of related genes was assessed by RNA sequence and Western blotting.ResultsTM4SF1-AS1 was highly expressed in high metastatic lung cancer cell line, and it was also significantly up-regulated in lymph node metastatic lung cancer and was associated with lymph node metastasis. Overexpression of TM4SF1-AS1 promoted the migration and invasion of lung cancer cells. Overexpression of TM4SF1-AS1 decreased the expression of E-Cadherin and increased the expression of Vimentin, Snail and Twist, while knockdown of TM4SF1-AS1 exhibited the opposite trend. Furthermore, RNA sequence analysis revealed that some signaling pathways, including PI3K/AKT signaling pathway, were enriched upon TM4SF1-AS1 overexpression. Western blotting further confirmed that the PI3K/AKT signaling pathway was activated by TM4SF1-AS1.ConclusionThis study illustrates that TM4SF1-AS1 promotes the migration and invasion of lung cancer cells by activating the PI3K/AKT signaling pathway. TM4SF1-AS1 might be a novel target of molecular treatment for lung cancer.

STUDY OF EFFECTS OF CIRCADIAN RHYTHMS ON SOLID TUMOR CELLS PROLIFERATION AND CHEMORESISTANCE

Circadian clock is a complex mechanism regulating many different physiological processes. Preclinical, epidemiological and clinical studies demonstrate association between circadian rhythms disruption and tumor initiation. Study of modulation of solid tumor cells biological properties through enhancement of clock mechanisms could attribute to the development of more effective chemo- and hormone therapy approaches. Aim: Evaluate the effects of ovarian and lung tumor cells synchronization with dexamethasone in vitro on cells sensitivity to cisplatin. Materials and methods: Metastatic ovarian cancer (n=3) and lung cancer (n=3) cell lines were obtained from patients tumors. Tumor cell cultivation was performed in accordance with the protocol. Artificial synchronization was performed with dexamethasone 200 nM introduction to the cell cultures. Doses of cisplatin used were 1.5 and 3.0 mg/ml. xCELLigence Real-Time Cell Analysis and Cell-IQ was used to measure proliferation and chemoresistance of tumor cells. Results: Each cell-line had individual morphological characteristics and proliferation parameters. Preliminary incubation with dexamethasone (2 h) had a stimulating effect on proliferation of all tumor cell lines (Slope min -4.3(0.3)хЕ ‘х10-3 - max 36.8(0.6)хЫх10'3, min 2.2(0.2)хЕ1х10'3- max 50.4(0.8)хЕ1х10'3), and increased their sensitivity to cisplatin (min -43(2.6)хЕ1х10-3 - max 57.5(0.6)хЕ1х10-3 и min -217,3(2,2) -1,9(0,1)хч-1х10-3 - max -1,9(0,1)хч'1х10'3, respectively. Conclusion: These results should be the platform for future studies of the interaction of clock mechanisms, cell cycle regulation and viability of tumor cells.

Structural identification of a fucose-containing 1,3-β-mannoglucan from Poria cocos and its anti-lung cancer CL1-5 cells migration via inhibition of TGFβR-mediated signaling

Poria cocos (Polyporacea), is a fungus used in traditional Chinese medicine. A study of the valuable sulfated polysaccharides (SPS) with the structure and pharmaceutical benefits from the mycelial culture conditions of P. cocos was attempted. The SPSs were fractionated by gel filtration chromatography to give a fucose-containing mannoglucan polysaccharide (denoted as FMGP): [Display omitted] The main skeleton was a 1,4-α-Man-interlaced-1,3-β-glucan with interlaced 6-O-α-l-fucosyl 1,4-α-Glc and 1,4-α-Gal branches. FMGP dramatically inhibited cell migration in the highly metastatic human lung cancer cell line CL1-5 cells. Mechanistically, FMGP dramatically downregulated the expression of TGFβRI and inhibited phosphorylation of FAK and AKT. Moreover, FMGP reduced the metastasis-related protein, Slug, expression. This is the first paper reporting a branched 1,3-β-mannoglucan from P. cocos and its anti-lung cancer CL1-5 cells migration activities.

Patient-Derived Metastatic Non-Small Cell Lung Cancer (NSCLC) Cell Lines from Untreated and Treated Patients Are Sensitive to Tumor Treating Fields (TTFields) in Vitro

Patient-Derived Metastatic Non-Small Cell Lung Cancer (NSCLC) Cell Lines from Untreated and Treated Patients Are Sensitive to Tumor Treating Fields (TTFields) in Vitro

Targeting β-tubulin/CCT-β complex induces apoptosis and suppresses migration and invasion of highly metastatic lung adenocarcinoma.

Metastasis, the movement of cancer cells from one site to another, is responsible for the highest number of cancer deaths, especially in lung cancer patients. In this study, we first identified a prognostic marker of lung adenocarcinoma, TCP-1 β subunit (chaperonin-containing TCP-1β; CCT-β). We showed a compound that disrupted the interaction of CCT-β with β-tubulin killed a highly metastatic non-small cell lung cancer cell line CL1-5 through inducing Endoplasmic reticulum stress and caspases activation. Moreover, at the dosage of EC20, the compound inhibited migration and invasion of the lung cancer cells by suppressing matrix metalloproteinase (MMP)-2/9 and epithelial-mesenchymal transition (EMT)-related proteins through downregulating mitogen-activated protein kinases (MAPKs), Akt/β-catenin and integrin-focal adhesion kinase signaling pathways. Unlike the anticancer drugs, such as Taxol, that target the adenosine triphosphate site of β-tubulin, this study reveals a therapeutic target, β-tubulin/CCT-β complex, for metastatic human lung adenocarcinoma. The study demonstrated CCT-β as a prognostic marker. Targeting β-tubulin/CCT-β complex caused apoptosis and inhibited invasion/migration of CCT-β overexpressed, highly metastatic lung adenocarcinoma.

Exosomal miR-499a-5p promotes cell proliferation, migration and EMT via mTOR signaling pathway in lung adenocarcinoma

Tumor-derived exosomes contain informative microRNAs involved in carcinogenesis, cell migration, invasion and epithelial–mesenchymal transition (EMT), eventually contributing to metastasis of cancers. This study aims to clarify which and how exosomal miRNA affects tumor carcinogenesis and metastasis. Among them, miR-499a-5p was upregulated in both highly metastatic lung cancer cell line and their exosomes. MiR-499a-5p overexpression promoted cell proliferation, migration and EMT, while miR-499a-5p knockdown suppressed these processes in vitro. Inhibition of miR-499a-5p by antagomirs administration restrained tumor growth in vivo. Consequently, miR499a-sufficient exosomes, derived from highly metastatic cell line, enhanced cell proliferation, migration and EMT via mTOR pathway, and the effect could be inhibited by miR-499a-5p inhibitor. The study reveals the potential diagnostic and therapeutic value of cancer-derived exosomal miR-499a-5p, and sheds a new insight on a novel molecular mechanism which modulates metastasis.

Novel Ran-RCC1 Inhibitory Peptide-Loaded Nanoparticles Have Anti-Cancer Efficacy In Vitro and In Vivo.

The delivery of anticancer agents to their subcellular sites of action is a significant challenge for effective cancer therapy. Peptides, which are integral to several oncogenic pathways, have significant potential to be utilised as cancer therapeutics due to their selectivity, high potency and lack of normal cell toxicity. Novel Ras protein-Regulator of chromosome condensation 1 (Ran-RCC1) inhibitory peptides designed to interact with Ran, a novel therapeutic target in breast cancer, were delivered by entrapment into polyethylene glycol-poly (lactic-co-glycolic acid) PEG-PLGA polymeric nanoparticles (NPs). A modified double emulsion solvent evaporation technique was used to optimise the physicochemical properties of these peptide-loaded biodegradable NPs. The anti-cancer activity of peptide-loaded NPs was studied in vitro using Ran-expressing metastatic breast (MDA-MB-231) and lung cancer (A549) cell lines, and in vivo using Solid Ehrlich Carcinoma-bearing mice. The anti-metastatic activity of peptide-loaded NPs was investigated using migration, invasion and colony formation assays in vitro. A PEG-PLGA-nanoparticle encapsulating N-terminal peptide showed a pronounced antitumor and anti-metastatic action in lung and breast cancer cells in vitro and caused a significant reduction of tumor volume and associated tumor growth inhibition of breast cancer model in vivo. These findings suggest that the novel inhibitory peptides encapsulated into PEGylated PLGA NPs are delivered effectively to interact and deactivate Ran. This novel Ran-targeting peptide construct shows significant potential for therapy of breast cancer and other cancers mediated by Ran overexpression.

Encapsulated miR-200c and Nkx2.1 in a nuclear/mitochondria transcriptional regulatory network of non-metastatic and metastatic lung cancer cells

BackgroundMicroRNAs are noncoding RNA molecules of ~ 22 nucleotides with diagnostic and therapeutic action [Curr Drug Targets, 2015. 16(12): p. 1381-403], affecting the expression of mRNAs involved in invasion, migration, and development [Oncotarget, 2015. 6(9): p. 6472-98, Cancer Manag Res, 2014. 6: p. 205-16]. miR-200c is part of the miR-200c/141 cluster on chromosome 12p13. Its mechanism of action when encapsulated is critical in lung cancer when patients express changes in miRNAs. miR-200c be a potential biomarkers for various lung diseases. As a potential therapy, miR-200c can impacts lives as target lung cancer is a leading cause of death with about 234,000 cases annually, high heterogeneity, complex screening, and a 5-year survival rate of 16% [CA Cancer J Clin, 2016.66(1): p. 7-30]. Encapsulated miR-200c efficiently enhances bioavailability, pharmacokinetics of therapeutics and targeting to cells, improves efficacy and provides potential cure.MethodsThe functions of miR-200c were determined in non-metastatic KW-634 and metastatic 821-T4 and 821-LN mouse lung cancer cell lines after various Nano vehicle treatments. Viability and cytotoxicity were determined by cell cycle and quantitative real-time PCR analyses were used to quantify levels of miR-200c and its target genes. In situ hybridization was used to visualize patterns of expression of miR-200c and others in the lung and many organs. Next-generation sequencing accession number GSE125000, invasion and migration assays using transwell chambers, and ActivSignal were used to elucidate the activation and inhibition profiles and perform direct expression measurements and modification of cellular components.ResultsDue to their effectiveness as intracellular vesicles transporting miR-200c into, out, and between parts of the cells, miR-200c is encapsulated with cholesterol, an integral part of the biological membranes with very important physical properties of the vehicle. Nano miR-200c showed efficient cellular uptake in KW-634, 821-T4, and 821-LN cells with important changes in gene expression and new isoforms. In KW-634, when treated with encapsulated miR-200c and compare to the non-encapsulated control; miR-29b increased by 5261-fold, and in 821-T4/LN, miR-1247 increased by 150-fold. Conversely, miR-1247 and miR-675 decreased by 348 and 1029.5-fold, respectively. miR-189 decreased by 34-fold in treated 821-T4 cells. A reduction of growth was observed only after 48 h of treatment with Nano miR-200c. Moreover, labeling the vehicle with carboxy-fluorescein showed that the encapsulated particles enter the nucleus and mitochondria. Encapsulated miR-200c by entering the cells, the nucleus and mitochondria, trigger changes in cell cycle phases with 4 up to 12 fold percentage in G2 and S phase respectively compare to miR-200c. Endogenous expression of Nkx2.1, miR-200c, and their targets Myb, Nfib, Six4 and Six1 showed an inverse correlation, as observed in development.ConclusionsLittle is known about miR-200c involvement in regulatory processes. Nano miR-200c affects invasion and migration mechanisms. The expression of encapsulated miR-200c contributes to the inhibition/activation of Kras, EMT, Hippo, regulatory pathways and blockers of metastasis. Delivery of miR-200c increases the expression of miR-29b, an EMY regulator, and miR-1247, an inhibitor of cancer genes, both tumor suppressors involved in lung metastasis. Encapsulated miR-200c act on different proteins that regulates cell cycle pathways. These findings represent a part of a regulatory network providing new insights towards improvement of therapy.

Genetic Alphabet Expansion Provides Versatile Specificities and Activities of Unnatural-Base DNA Aptamers Targeting Cancer Cells

The potential of genetic alphabet expansion technologies using artificial extra base pairs (unnatural base pairs) has been rapidly expanding and increasing. We present that the hydrophobic unnatural base, 7-(2-thienyl)imidazo[4,5-b]pyridine (Ds), which acts as a fifth letter in a DNA library, provides a series of high-affinity DNA aptamers with versatile binding specificities and activities to cancer cells. These Ds-containing DNA aptamers were generated by a method called cell-ExSELEX to target three breast cancer cell lines: MCF7, MDA-MB-231, and T-47D. Aptamer 14A-MCF7, which targets MCF7 cells, specifically binds to MCF7 cells, but not other cancer cell lines. Aptamer 07-MB231, which targets MDA-MB-231 cells, binds to a series of metastatic bone and lung cancer cell lines. Aptamer 05-MB231 targets MDA-MB-231 cells, but it also binds to all of the cancer and leukemia cell lines that we examined. None of these aptamers bind to normal cell lines, such as MCF10A and HUVEC. In addition, aptamers 14A-MCF7 and 05-MB231 are internalized within the cancer cells, and aptamer 05-MB231 possesses anti-proliferative properties against most cancer cell lines that we examined. These aptamers and the generation method are broadly applicable to cancer cell imaging, biomarker discovery, cancer cell profiling, anti-cancer therapies, and drug delivery systems.

PH-sensitive tangeretin-ZnO quantum dots exert apoptotic and anti-metastatic effects in metastatic lung cancer cell line

Most cancer patients die as a consequence of distant metastases, which are frequently unresponsive to cancer therapy. This study focuses on the anti-tumorigenic and anti-metastatic properties of tangeretin-zinc oxide quantum dots (Tan-ZnO QDs) against the NCI-H358 cell line. Tan-ZnO QDs are pH-sensitive and capitalize on the acidic pH maintained in the tumor microenvironment; therefore, targeted drug delivery is directed specifically to cancer cells, leaving the normal cells less affected. Tan was loaded into synthesized ZnO QDs, and drug loading was analyzed using Fourier transform infrared (FTIR) spectroscopy and ultraviolet-visible (UV–Vis) spectrometry. Crystalline phase and particle size were measured using transmission electron microscopy (TEM) and X-ray diffraction (XRD). Drug release was evaluated in buffered solutions with differing pH for up to 15 h. The results confirmed stable drug release (80%) in an acidic pH. Tan-ZnO QDs induced significant cytotoxicity in NCI-H358 metastatic cells, while not markedly affecting HK-2 human normal cells. Morphology of treated H358 cells analyzed via atomic force microscopy (AFM) showed an increased surface roughness and pores. Further, the number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells increased after treatment with Tan-ZnO QDs. DNA fragmentation was also induced after treatment with increasing concentrations of Tan-ZnO QDs in H358 cells. We also confirmed regulation of apoptosis via expression levels of Bax and Bcl-2 proteins; G2/M phase cell cycle arrest was observed. Additionally, cell proliferation and migration drastically decreased, and cell invasion and migration, hallmarks of metastasis, were significantly inhibited in H358 cells. Matrix metalloproteinase (MMP)2 and MMP9, markers of metastasis, as well as vascular endothelial growth factor (VEGF), a marker of angiogenesis, were significantly downregulated upon treatment with Tan-ZnO QDs. In conclusion, our novel formulation destabilized H358 cells by using its acidic tumor microenvironment, thereby regulating cell apoptosis, proliferation, and metastatic properties.

Viola Yedoensis Suppresses Cell Invasion by Targeting the Protease and NF-κB Activities in A549 and Lewis Lung Carcinoma Cells.

Cancer metastasis is a vital trait in malignancies with complicated early diagnosis and therapeutic management. Therefore, the development of new remedies and the utilization of natural medicines that target metastasis are of great interest and have been studied extensively. Chinese medicinal herbs have various anti-carcinogenesis properties; however, the in vitro effect and mechanism of Viola yedoensis on cancer cell metastasis remains poorly understood. V. yedoensis extracts (VYE) can suppress the invasion of a highly metastatic human lung cancer cell line, A549 cells. According to gelatin zymography and casein zymography assays, VYE inhibited the activities of matrix metalloproteinases (MMPs) and urokinase-type plasminogen activator (u-PA). The results of reverse transcription-polymerase chain reaction and Western blotting revealed that VYE can alter the expression of proteinase inhibitor. VYE also suppressed the DNA binding activity of nuclear factor-kappa B. We concluded that VYE may inhibit tumor invasion by suppressing the activities of MMP and u-PA in lung cancer cells.

PPARGC1A is upregulated and facilitates lung cancer metastasis

Lung cancer remains a leading cause of cancer-related mortality, with metastatic progression remaining the single largest cause of lung cancer mortality. Hence it is imperative to determine reliable biomarkers for lung cancer prognosis. We performed quantitative real-time PCR (qRT-PCR) analysis to explore epithelial-mesenchymal transition (EMT) inducers that regulate EMT process in three patients with advanced lung cancer disease. Peroxisome proliferator-activated receptor gamma (PPARGC1A) was uniformly the topmost overexpressed gene in all three human non-small cell lung cancer (NSCLC) patient samples. Further evaluation in human normal lung and metastatic lung cancer cell lines revealed that the expression of PPARGC1A was upregulated in metastatic lung cancer cell lines. Metagenomic analysis revealed direct correlation among PPARGC1A, zinc-finger transcription factor snail homolog 1 (SNAI1), and metastatic lung disease. Upregulation of PPARGC1A transcript expression was independent of a differential upregulation of the upstream AMP-dependent protein kinase (AMPK) activation or steady state expression of the silent mating type information regulation 2 homolog 1 (SIRT1). Xenograft tail vein colonization assays proved that the high expression of PPARGC1A was a prerequisite for metastatic progression of lung cancer to brain. Our results indicate that PPARGC1A might be a potential biomarker for lung cancer prognosis.

Long Intergenic Noncoding RNA 319 (linc00319) Promotes Cell Proliferation and Invasion in Lung Cancer Cells by Directly Downregulating the Tumor Suppressor MiR-32.

Long non-coding RNAs (lncRNAs) have been shown to play important regulatory roles in the pathogenesis and progression of multiple cancers. Here, we investigated the role of long intergenic non coding RNA 319 (linc00319) in the proliferation and invasion of lung cancer cells. We found that, compared with normal lung cell line HBE, linc00319 was increased in low metastatic lung cancer cell lines PAa and AgiY-83a, and further increased in high metastatic lung cancer cell lines A549 and Anip-973. Then, different concentrations of pcDNA-linc00319 expression vector and different concentrations of linc00319 siRNA were respectively transfected into A549 lung cancer cells. The results showed that linc00319 increased the proliferation and invasion of A549 cells, and suppressed cell apoptosis, in a dose-dependent manner. In contrast, linc00319 siRNA suppressed A549 cell proliferation and invasion, and promoted cell apoptosis, in a dose-dependent manner. The online bioinformatic tool RNAhybrid revealed that linc00319 potentially bound with the miR-32, which functioned as a tumor suppressor in lung cancer. Luciferase acitivity and RNA pull-down assays comfirmed that linc00319 directly bound with miR-32. Linc00319 could negatively regulate the expression of miR-32 and positively regulate the protein levels of miR-32 target genes, including AURKA, SOX9 and TWIST1. In conclusion, linc00319 promotes cell proliferation and invasion in lung cancer cells by directly binding with and downregulating the tumor suppressor miR-32.

Abstract 4118: Honokiol inhibits lung cancer brain metastasis through inhibition of STAT3 signaling pathway

Abstract Lung cancer is the leading cause of cancer death in the United States, and metastasis to lymph-node (LN) and distal organs especially brain leads to sever complications and are the major cause of death. Preventing lung cancer development and metastases is important strategy to reduce lung cancer mortality. Honokiol (HNK), a natural compound present in magnolia bark extracts, has a good bioavailability profile and recently has also been shown to readily cross both the blood-brain barrier (BBB). We previously demonstrated that HNK can prevent and inhibit squamous lung cancer cell carcinoma both in-vitro and in-vivo. In the current study, we evaluated the anti-metastatic effects of HNK in both LN and brain murine models of lung tumor metastasis. The H2030-BrM3 (BR-brain seeking) lung tumor cells stably transfected with luciferase and GFP were orthotopically injected into lung for LN metastases, or directly to the left ventricle of mouse heart for brain metastases, LN or brain metastasis was monitored using a non-invasive IVIS bio-luminescent imaging system. To test the efficacy of HNK in preventing tumor cells migrating to LN or brain, mice were given 10 mg/kg per body weight HNK by aerosol (for lung to LN metastasis model) or oral gavage starting the day after tumor cell injection, our results reveal that HNK significantly prevented the metastasis of lung cancer cells to LN and brain. Our results demonstrate that HNK decreased LN metastases incidence to 30% compare to 100% in control mice, and inhibited brain metastasis near 70% compare to control. Furthermore, analysis of HNK's mechanism of action by utilizing both RNA sequencing and receptor tyrosine kinase assay suggests that its effect is primarily mediated by inhibiting STAT3 pathway. HNK specifically inhibits STAT3 phosphorylation, and knock-down STAT3 totally abrogated the anti-metastasis effects of HNK in brain metastatic lung cancer cell lines, PC9-BrM3 and H2030-BrM3. These finding suggest that HNK could provide novel chemopreventive or therapeutic options for preventing both lung tumor progression and lung cancer brain metastasis. Citation Format: Yongik Lee, Jing Pan, Qi Zhang, Yian Wang, Ming You. Honokiol inhibits lung cancer brain metastasis through inhibition of STAT3 signaling pathway. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4118.