Inhibitory effect and mechanism of hirsuteine on NCI­H1299 lung cancer cell lines.

Traditionally, the bark of Uncaria rhynchophylla (UR) has been employed for the treatment of hypertension, cancer, convulsions, haemorrhage, autoimmune disorders and other ailments. The primary aim of the present study was to explore the antiproliferative activity of hirsuteine (HTE) isolated from UR over a range of concentrations in human NSCLC NCI-H1299 cells and to explore the mechanisms underlying its therapeutic efficacy. The effects of HTE on cell viability were examined using Cell Counting Kit-8 (CCK-8) and colony formation assays, while apoptosis was assessed by flow cytometry. Cell cycle progression was additionally evaluated via propidium iodide staining, while reverse transcription-quantitative PCR and western blotting methods were employed to assess the protein levels and genes related to apoptosis and progression of the cell cycle, respectively. NCI-H1299 cell proliferation was markedly suppressed by HTE in a time- and dose-dependent manner. However, clear changes in cell morphology were also induced, resulting in G0-G1 phase cell cycle arrest, which was associated with cyclin E and CDK2 downregulation. HTE additionally induced robust NSCLC NCI-H1299 cell apoptosis, downregulation of Bcl-2 and upregulation of cytoplasmic cytochrome C, Bax, Apaf1, cleaved caspase-3 and cleaved caspase-9, which together drove the observed apoptotic cell death. HTE could effectively suppress human NSCLC NCI-H1299 cell growth by inducing apoptotic death in a dose-dependent fashion in vitro, therefore elucidating the mechanism by which this phytomedicine acts as a potent anticancer compound that warrants study as a treatment for human NSCLC patients.

Preparation of Nereid oligopeptide and investigation of the mechanism underlying the induction of apoptosis in human lung cancer H1299 cells.

In the present study, oligopeptides from Nereid (Perinereis aibuhitensis) were prepared via enzymatic hydrolysis, and the mechanism underlying the induction of apoptosis in H1299 cells was investigated. According to the analysis of the inhibition rate on proliferation, alkaline protease demonstrated the best enzymatic efficiency. The optimal conditions for hydrolysis were as follows: 50˚C and pH 10 for 6 h; a material­to­liquid ratio of 1:1 (g/ml); and addition of 400 U/g enzyme. The hydrolysates were purified using ultrafiltration, anion chromatography, gel filtration chromatography, and high­performance liquid chromatography. The Nereid oligopeptide (NOP), with a molecular weight of 841 kDa and an amino acid sequence of glutamine­isoleucine­asparagine­glutamine­histidine­leucine, was obtained. NOP inhibited the proliferation of H1299 cells in a time­ and dose­dependent manner. Morphological changes and apoptosis were also induced by NOP in H1299 cells. The western blot analysis revealed that the B­cell lymphoma 2/Bcl­2 associated X (Bcl­2/Bax) ratio was reduced by 24.7% in the NOP treatment group compared with the control group. The relative expression levels of cleaved caspase­9 (cleaved­CASP9) and cleaved caspase­3 (cleaved­CASP3) in the NOP treatment group were 2.55­ and 1.71­fold higher than those measured in the control group, respectively. These results suggested that NOP exerts antitumor effects by influencing the proliferation and apoptosis of H1299 cells.

A chimeric switch-receptor PD1-DAP10-41BB augments NK92-cell activation and killing for human lung Cancer H1299 Cell.

Engineered natural killer (NK) cell-based therapies have been potentially broadly applicable and exhibited promising results in clinical trials, particularly in the fight against cancers. NK cell immunotherapy however always remains variable. One major obstacle is the inhibitory pathway including PD1/PDL1, providing tumor cells an escape mechanism from immunosurveillance. In this regard, we rationally designed a chimeric switch-receptor (CSR) PD1-DAP10-41BB, which comprising the ectodomain of PD1 fused to the co-stimulatory receptor DAP10 and 41BB. Therefore, by exchanging the transmembrane and cytoplasmic tail of PD1 with positive costimulatory molecules DAP10 and 41BB signaling domains, the negative PD1/PDL1 signal pathway was thus converted into a positive one. This CSR-expressing NK92 cells showed a typical parental NK92 phenotype and improved cytotoxicity against human lung cancer H1299 cells. Besides, the expression of CSR elicited a significant increase of effector molecules such as perforin and granzymes, which can induce apoptosis of H1299 cells. More importantly, in the solid tumor cell H1299-bearing mice model, the CSR-modified NK92 cells significantly inhibited tumor growth. Collectively, we demonstrated that expression of PD1-DAP10-41BB augmented NK92-cell activation and killing in vitro and in vivo, which provides a considerable avenue of using NK-tailored chimeric receptor engineered NK92 cells to treat a wide range of solid tumors.

Effects of neferine on invasion and migration of non-small cell lung cancer H1299 cells via inhibiting ROCK pathway / 中国药理学通报

Aim To observe the inhibitory effect of neferine(Nef)on the migration and invasion of non-small cell lung cancer(NSCLC)H1299 cells by blocking ROCK pathway.Methods H1299 cells were taken for in vitro culture, and treated with different concentrations of Nef.H1299 cell viability was measured by CCK-8 method to determine the dose of the experimental group.The migration and invasion abilities of H1299 cells were detected by cell scratch test and Transwell chamber test.The expression of matrix metalloproteinases MMP-2 and MMP-9 secreted from lung cancer cells was detected by enzyme linked immunosorbent assay(ELISA).The protein level of ROCK1 in H1299 cells was tested by real-time fluorescent quantitative PCR and Western blot; the binding mode and affinity between Nef and ROCK1 were stimulated by AutoDock semi flexible docking method.Results The doses of Nef in the experimental group were determined as 4, 6 and 10 μmol·L-1.These three concentrations of Nef could inhibit the migration and invasion of H1299 lung cancer cells to a certain degree in a dose-dependent manner.At the same time, Nef reduced the expression of MMP-2, MMP-9 and ROCK1 proteins related to the migration and invasion of the cancer cells.In addition, the affinity of Nef to ROCK1 was significantly higher than that of fasudil, an inhibitor of ROCK, and the binding force was stronger to A-chain of ROCK1.Conclusions As a potential natural anticancer compound, Nef can inhibit the migration and invasion of NSCLC by reducing the expression of MMP-2, MMP-9 and ROCK1 proteins related to the migration and invasion of the cancer cells.

[Effects of Pigment Epithelium-derived Factor and Its Peptides on Proliferation,
Apoptosis and Migration of Non-small Cell Lung Cancer].

BACKGROUND: The anti-tumor effect of pigment epithelium-derived factor (PEDF) has been widely confirmed. However, the anti-tumor effect of its peptides is rarely reported. This study aims to investigate the effects of PEDF and its peptides on the apoptosis and migration of non-small cell lung cancer (NSCLC). METHODS: In this study, A549 cells and H1299 cells were selected as the research object, and the cells were divided into normal group, PEDF treatment group, 34 peptide treatment group, 44 peptide treatment group and 34+44 peptide treatment group by administering different drugs at the same concentration to the cells. The proliferation activity of cells in each group was detected by CCK-8 method; the migration ability of cells was detected by scratch test; the expression levels of apoptosis related proteins such as protein kinase 3 (RIP3) and cleaved-caspase-3 were detected by Western blot; the expression levels of epithelial mesenchymal transition (EMT) markers in each group, such as cadherin (E-cadherin) and α-smooth muscle actin (α-SMA) were detected by Western blot; the apoptosis rate of each group was detected by flow cytometry. RESULTS: The results of CCK-8 showed that PEDF and its peptides could inhibit cell proliferation, and the inhibitory effect of 34+44 peptide was the strongest (P<0.05); Observation under the microscope found that PEDF and its peptides can inhibit the proliferation and mesenchymal transformation of A549 cells and H1299 cells, and the inhibitory effect of the 34+44 peptide group is the most obvious; Western blot indicated that compared with other groups, the expressions of cleaved-caspase-3 and RIP3 in 34+44 peptide group were significantly higher (P<0.05), and the expressions of EMT protein E-cadherin were higher, the expression of α-SMA decreased (P<0.05); The results of flow cytometry showed that the apoptosis rate of 34+44 peptide group was significantly higher than those of other groups (P<0.05); The scratch test showed that compared with all the other groups, the healing rate of 34+44 peptide group was the lowest (P<0.05). CONCLUSIONS: 34+44 combination peptide can better promote the apoptosis of NSCLC, inhibit the migration of NSCLC, and thereby inhibit the growth of NSCLC.

Design, Synthesis, Biological Evaluation and In Silico Study of Benzyloxybenzaldehyde Derivatives as Selective ALDH1A3 Inhibitors.

Aldehyde dehydrogenase 1A3 (ALDH1A3) has recently gained attention from researchers in the cancer field. Several studies have reported ALDH1A3 overexpression in different cancer types, which has been found to correlate with poor treatment recovery. Therefore, finding selective inhibitors against ALDH1A3 could result in new treatment options for cancer treatment. In this study, ALDH1A3-selective candidates were designed based on the physiological substrate resemblance, synthesized and investigated for ALDH1A1, ALDH1A3 and ALDH3A1 selectivity and cytotoxicity using ALDH-positive A549 and ALDH-negative H1299 cells. Two compounds (ABMM-15 and ABMM-16), with a benzyloxybenzaldehyde scaffold, were found to be the most potent and selective inhibitors for ALDH1A3, with IC50 values of 0.23 and 1.29 µM, respectively. The results also show no significant cytotoxicity for ABMM-15 and ABMM-16 on either cell line. However, a few other candidates (ABMM-6, ABMM-24, ABMM-32) showed considerable cytotoxicity on H1299 cells, when compared to A549 cells, with IC50 values of 14.0, 13.7 and 13.0 µM, respectively. The computational study supported the experimental results and suggested a good binding for ABMM-15 and ABMM-16 to the ALDH1A3 isoform. From the obtained results, it can be concluded that benzyloxybenzaldehyde might be considered a promising scaffold for further drug discovery aimed at exploiting ALDH1A3 for therapeutic intervention.

Effects of Pigment Epithelium-derived Factor and Its Peptides on Proliferation, Apoptosis and Migration of Non-small Cell Lung Cancer / 中国肺癌杂志

BACKGROUND@#The anti-tumor effect of pigment epithelium-derived factor (PEDF) has been widely confirmed. However, the anti-tumor effect of its peptides is rarely reported. This study aims to investigate the effects of PEDF and its peptides on the apoptosis and migration of non-small cell lung cancer (NSCLC).@*METHODS@#In this study, A549 cells and H1299 cells were selected as the research object, and the cells were divided into normal group, PEDF treatment group, 34 peptide treatment group, 44 peptide treatment group and 34+44 peptide treatment group by administering different drugs at the same concentration to the cells. The proliferation activity of cells in each group was detected by CCK-8 method; the migration ability of cells was detected by scratch test; the expression levels of apoptosis related proteins such as protein kinase 3 (RIP3) and cleaved-caspase-3 were detected by Western blot; the expression levels of epithelial mesenchymal transition (EMT) markers in each group, such as cadherin (E-cadherin) and α-smooth muscle actin (α-SMA) were detected by Western blot; the apoptosis rate of each group was detected by flow cytometry.@*RESULTS@#The results of CCK-8 showed that PEDF and its peptides could inhibit cell proliferation, and the inhibitory effect of 34+44 peptide was the strongest (P<0.05); Observation under the microscope found that PEDF and its peptides can inhibit the proliferation and mesenchymal transformation of A549 cells and H1299 cells, and the inhibitory effect of the 34+44 peptide group is the most obvious; Western blot indicated that compared with other groups, the expressions of cleaved-caspase-3 and RIP3 in 34+44 peptide group were significantly higher (P<0.05), and the expressions of EMT protein E-cadherin were higher, the expression of α-SMA decreased (P<0.05); The results of flow cytometry showed that the apoptosis rate of 34+44 peptide group was significantly higher than those of other groups (P<0.05); The scratch test showed that compared with all the other groups, the healing rate of 34+44 peptide group was the lowest (P<0.05).@*CONCLUSIONS@#34+44 combination peptide can better promote the apoptosis of NSCLC, inhibit the migration of NSCLC, and thereby inhibit the growth of NSCLC.

[Screening and Identification of the Peptides Specifically Binding to 
Human Non-small Cell Lung Cancer NCI-H1299 Cells].

BACKGROUND: Non-small cell lung cancer (NSCLC) is the most common histological type of lung cancer, and one of the malignant tumor with the highest mortality. As the main part of the optical molecular imaging probe, peptide can realize the early screening and diagnosis of tumor and improve the survival rate of patients. The aim of this study was to screen the small-molecule peptide that highly binds to NSCLC NCI-H1299 cells using in vivo phage display technology and to identify their binding specificity by in vitro experiment. METHODS: To prepare a tumor-bearing nude mouse model of NCI-H1299 cells, after 3 rounds of in vivo screening with Ph.D.-C7CTM Peptide Library, phage clones were randomly picked, using immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) to identify the affinity of phage clones to NCI-H1299 cells. The positive monoclonal phages DNA was extracted and sequenced to obtain the amino acid sequence of the peptides. The peptides with the highest repetition rate was chemically synthesized and labeled with fluorescein (FITC) to prepare optical molecular probe. We preliminary identified the specificity of the probe binding to lung cancer cells by in vitro experiment. RESULTS: After three rounds of in vivo screening, the phages enrichment rate was 341.3 times compared with the first round. Immunohistochemical staining showed that with the increase of screening times, the phages binding to tumor tissues continued to increase, and the binding amount was significantly higher than normal tissues; ELISA results showed that 20 clones among the 30 randomly selected phage clones were positive. After sequencing, the peptide with the highest repetition rate was synthesized and named NSP1; Methyl thiazolyl tetrazolium assay (MTT) and would healing assay showed that NSP1 will not affect cell proliferation and migration. Flow cytometry and immunofluorescence showed specific binding of NSP1 to NCI-H1299 cells. CONCLUSIONS: We successfully obtained the peptide NSP1 that specifically binds to lung cancer NCI-H1299 cells by in vivo phage display, which provide a theoretical basis for NSCLC early diagnosis and targeted therapy.

Screening and Identification of the Peptides Specifically Binding to Human Non-small Cell Lung Cancer NCI-H1299 Cells / 中国肺癌杂志

BACKGROUND@#Non-small cell lung cancer (NSCLC) is the most common histological type of lung cancer, and one of the malignant tumor with the highest mortality. As the main part of the optical molecular imaging probe, peptide can realize the early screening and diagnosis of tumor and improve the survival rate of patients. The aim of this study was to screen the small-molecule peptide that highly binds to NSCLC NCI-H1299 cells using in vivo phage display technology and to identify their binding specificity by in vitro experiment.@*METHODS@#To prepare a tumor-bearing nude mouse model of NCI-H1299 cells, after 3 rounds of in vivo screening with Ph.D.-C7CTM Peptide Library, phage clones were randomly picked, using immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) to identify the affinity of phage clones to NCI-H1299 cells. The positive monoclonal phages DNA was extracted and sequenced to obtain the amino acid sequence of the peptides. The peptides with the highest repetition rate was chemically synthesized and labeled with fluorescein (FITC) to prepare optical molecular probe. We preliminary identified the specificity of the probe binding to lung cancer cells by in vitro experiment.@*RESULTS@#After three rounds of in vivo screening, the phages enrichment rate was 341.3 times compared with the first round. Immunohistochemical staining showed that with the increase of screening times, the phages binding to tumor tissues continued to increase, and the binding amount was significantly higher than normal tissues; ELISA results showed that 20 clones among the 30 randomly selected phage clones were positive. After sequencing, the peptide with the highest repetition rate was synthesized and named NSP1; Methyl thiazolyl tetrazolium assay (MTT) and would healing assay showed that NSP1 will not affect cell proliferation and migration. Flow cytometry and immunofluorescence showed specific binding of NSP1 to NCI-H1299 cells.@*CONCLUSIONS@#We successfully obtained the peptide NSP1 that specifically binds to lung cancer NCI-H1299 cells by in vivo phage display, which provide a theoretical basis for NSCLC early diagnosis and targeted therapy.

YAP mediates the positive regulation of hnRNPK on the lung adenocarcinoma H1299 cell growth.

Lung cancer is the leading cause of cancer death worldwide, and non-small cell lung cancer (NSCLC) accounts for 80%-85% of diagnostic cases. The molecular mechanisms of NSCLC pathogenesis are not well understood. Heterogeneous nuclear ribonucleoprotein K (hnRNPK) is a multifunctional protein that regulates gene expression and signal transduction and closely associated with tumorigenesis, but its mechanism of action in the pathogenesis of NSCLC is unclear. In this study, we observed that the expression pattern of hnRNPK in H1299 lung adenocarcinoma cells varied depending on the cell density in culture. Moreover, hnRNPK stimulated the ability of proliferation and colony formation of H1299 cells, which is important for the multilayered cell growth in culture. We further investigated whether there is an association between hnRNPK and the elements involved in the cell contact inhibition pathway. By using quantitative reverse transcriptase-polymerase chain reaction assay and a YAP activity reporter system, we found that hnRNPK upregulated the mRNA and protein levels and transcriptional activity of Yes-associated protein 1 (YAP), a master negative regulator of Hippo contact inhibition pathway. Furthermore, YAP knockdown with siRNA abolished the stimulatory effect of hnRNPK on H1299 cell proliferation. These results suggested that YAP could be one of the effectors of hnRNPK. Our data may provide new clues for further understanding the biological functions of hnRNPK, particularly in the context of lung adenocarcinoma oncogenesis.

Serine Protease from Nereis virens Inhibits H1299 Lung Cancer Cell Proliferation via the PI3K/AKT/mTOR Pathway.

This study explores the in vitro anti-proliferative mechanism between Nereis Active Protease (NAP) and human lung cancer H1299 cells. Colony formation and migration of cells were significantly lowered, following NAP treatment. Flow cytometry results suggested that NAP-induced growth inhibition of H1299 cells is linked to apoptosis, and that NAP can arrest the cells at the G0/G1 phase. The ERK/MAPK and PI3K/AKT/mTOR pathways were selected for their RNA transcripts, and their roles in the anti-proliferative mechanism of NAP were studied using Western blots. Our results suggested that NAP led to the downregulation of p-ERK (Thr 202/Tyr 204), p-AKT (Ser 473), p-PI3K (p85), and p-mTOR (Ser 2448), suggesting that NAP-induced H1299 cell apoptosis occurs via the PI3K/AKT/mTOR pathway. Furthermore, specific inhibitors LY294002 and PD98059 were used to inhibit these two pathways. The effect of NAP on the downregulation of p-ERK and p-AKT was enhanced by the LY294002 (a PI3K inhibitor), while the inhibitor PD98059 had no obvious effect. Overall, the results suggested that NAP exhibits antiproliferative activity by inducing apoptosis, through the inhibition of the PI3K/AKT/mTOR pathway.

Dual Anti-cancer and Anti-Itch Activity of PD176252 Analogues: Design, Synthesis and Biological Evaluation.

BACKGROUND: Cancer patients treated with targeted anti-cancer drug suffer from itch or pruritus. Itch or pruritus is an unpleasant sensation that brings about a negative impact on quality of life, and serious itch may lead to dose reduction and even discontinuation. Gastrin releasing peptide receptor (GRPR) plays a critical role in itch, inflammation and cancer, and GRPR antagonist has obvious effect on cancer, inflammation and itch. The aim of this paper is to develop a new agent with anti-cancer and anti-itch activity. METHODS: A series of GRPR antagonist PD176252 analogues (3a-3l) were designed and synthesized. Both anticancer and anti-itch activities were evaluated. Anti-cancer activity was evaluated in three human cancer cell lines in vitro, the anti-itch activity in evaluated with Kunming mice by intrathecal injection of chloroquine phosphate as a modeling medium. And the cytotoxicity on normal cells was evaluated. RESULTS: Of the tested compounds, compound 3i showed potently anti-cancer activity to all cancer cell lines tested with IC50 values of 10.5µM (lung), 11.6µM (breast) and 12.8µM (liver) respectively and it also showed significant inhibition of the scratching behavior. Comparing with PD17625, compound 3i and 3g gave better inhibition activities against all cancer cell lines, compound 3b, 3c and 3i showed better anti-itch activity. The compound 3i is safe for normal breast and liver normal cells, but it has high cytotoxicity on normal lung cell. CONCLUSION: The synthesized compounds have dual anti-cancer and anti-itch activity, so the development of drug with dual anti-tumor and anti-itch property is possible.

Structure Identification of ViceninII Extracted from Dendrobium officinale and the Reversal of TGF-ß1-Induced Epithelial⁻Mesenchymal Transition in Lung Adenocarcinoma Cells through TGF-ß/Smad and PI3K/Akt/mTOR Signaling Pathways.

ViceninII is a naturally flavonoid glycoside extracted from Dendrobium officinale, a precious Chinese traditional herb, has been proven to be valuable for cancer treatment. Transforming growth factor-ß1 (TGF-ß1), promotes the induction of epithelial⁻mesenchymal transition (EMT), a process involved in the metastasis of cells that leads to enhanced migration and invasion. However, there is no previously evidence that ViceninII has an inhibitory effect on cancer metastasis, specifically on the TGF-ß1-induced EMT process in lung adenocarcinoma cells. In this experiment, we used UV, ESIMS, and NMR to identify the structure of ViceninII.A549 and H1299 cells were treated with TGF-ß1 in the absence and presence of ViceninII, and subsequent migration and invasion were measured by wound-healing and transwell assays. The protein localization and expressions were detected by immunofluorescence and Western blotting. The results indicated that TGF-ß1 induced spindle-shaped changes, increased migration and invasion, and upregulated or downregulated the relative expression of EMT biomarkers. Meanwhile, these alterations were significantly inhibited when co-treated with ViceninII and inhibitors LY294002 and SB431542. In conclusion, ViceninII inhibited TGF-ß1-induced EMT via the deactivation of TGF-ß/Smad and PI3K/Akt/mTOR signaling pathways.This is the first time that the anti-metastatic effects of ViceninII have been demonstrated, and their molecular mechanisms provided.

Leukamenin E, an ent-kaurane diterpenoid, is a novel and potential keratin intermediate filament inhibitor.

Many ent-kaurane diterpenoids exhibit notable antitumor activity in vitro and in vivo, and some have been used as cancer therapeutic agents in China. In this study, we identified a novel molecular target of leukamenin E, an ent-kaurane diterpenoid, using an available whole-cell model in combination with immunofluorescence imaging and mass spectrometry (MS). The cytoskeleton-disrupting drugs cytochalasin B and colchicine caused the depolymerization of microfilaments and the collapse of microtubules and vimentin filaments, respectively, but had little effects on HepG2 and NCI-H1299 cells spreading as well as keratin filament (KF) reassembly, indicating that KFs are involved in cell spreading. Leukamenin E blocked HepG2 and NCI-H1299 cells adhesion/spreading and KF reassembly at subtoxic concentrations, indicating that leukamenin E may target KFs. Moreover, leukamenin E, at 3 µM for 24 h or 10 µM for 3 h, induced massive KF depolymerization in well-spread HepG2 and NCI-H1299 cells treated with/without cytochalasin B and colchicine. MS analysis indicated that leukamenin E could covalently modify amino acid residue(s) in a synthetic peptide based on keratin 1 and keratin 10 sequences, suggesting that covalent modification of the synthetic peptide by leukamenin E caused assembly inhibition or disrupted KF polymerization in HepG2 and NCI-H1299 cells. In addition, acridine orange/ethidium bromide staining and western blotting confirmed that there was no correlation between the KF-disrupting effects and apoptosis or keratin expression. Thus, we propose that leukamenin E is a novel inhibitor of KF assembly, and as such, can serve as a chemical probe of KF functions and a potential molecular target for ent-kaurane diterpenoid-based therapeutics.

Mitochondria-mediated apoptosis was induced by oleuropein in H1299 cells involving activation of p38 MAP kinase.

Lung cancer is the main health threat in the world. Recently, oleuropein has been reported to have potent antioxidant and anticancer activities. However, the antitumor effects of oleuropein on H1299 cells are not well understood. Therefore, the purpose of this paper is tantamount to explore the effects of oleuropein on H1299 cells and its underlying mechanism that may be involved. Oleuropein treatment in H1299 cells resulted in cell cycle distribution at G2 /M arrest and apoptosis in a dose-dependent manner. Mitochondria-mediated apoptosis was verified by the increase in Bax/Bcl-2 ratio, release of cytochrome c, and activation of caspase-3 on oleuropein-induced H1299 cells. In addition, our data also demonstrated that the p38 mitogen-activated protein kinase (MAPK) signaling pathway has a critical role in oleuropein-induced apoptosis. Moreover, we used transcriptome analysis to identify differentially expressed genes (DEGs) in H1299 cells by oleuropein and SB203580 treatment. Many DEGs were annotated to metabolic pathways, cell cycle, pathways in cancer, MAPK signaling pathway by Kyoto Encyclopedia of Genes and Genomes and Gene ontology enrichment methods. Network and expression analysis found that DEGs, including RPS6A5, GADD45A, and MKP, play a key role in the p38 MAPK signaling pathway. In H1299 cells, oleuropein resulted in the expression of numerous genes related to cell signaling, metabolism pathway and directly associated with apoptosis. These results illustrated that oleuropein-induced apoptosis via mitochondrial apoptotic cascade was activated by the p38 MAPK signaling pathway in H1299 cells. Thus, oleuropein as a natural compound and therapeutic drug has potential application value in the treatment of lung cancer.

eIF2α kinases PERK and GCN2 act on FOXO to potentiate FOXO activity.

PERK and GCN2 are eIF2α kinases known to mediate the effects of ER stress and respond to an array of diverse stress stimuli. Previously, we reported that ER stress potentiates insulin resistance through PERK-mediated FOXO phosphorylation. Inhibition of PERK improves cellular insulin responsiveness at the level of FOXO activity. Here we provide further evidence that FOXO is required for the functional output of PERK by showing that lowering FOXO activity ameliorates a PERK gain-of-function phenotype in Drosophila. More importantly, we present results demonstrating that GCN2 acts similarly to PERK to promote FOXO activity. Regulation of FOXO by GCN2 is evolutionarily conserved and can be compensated for by PERK. The combination of these mechanisms may contribute to the complex regulatory network between PERK, GCN2, and FOXO, which has been implicated in the development and progression of a variety of diseases.

DNA Damage-Response Pathway Heterogeneity of Human Lung Cancer A549 and H1299 Cells Determines Sensitivity to 8-Chloro-Adenosine.

Human lung cancer H1299 (p53-null) cells often display enhanced susceptibility to chemotherapeutics comparing to A549 (p53-wt) cells. However, little is known regarding to the association of DNA damage-response (DDR) pathway heterogeneity with drug sensitivity in these two cells. We investigated the DDR pathway differences between A549 and H1299 cells exposed to 8-chloro-adenosine (8-Cl-Ado), a potential anticancer drug that can induce DNA double-strand breaks (DSBs), and found that the hypersensitivity of H1299 cells to 8-Cl-Ado is associated with its DSB overaccumulation. The major causes of excessive DSBs in H1299 cells are as follows: First, defect of p53-p21 signal and phosphorylation of SMC1 increase S phase cells, where replication of DNA containing single-strand DNA break (SSB) produces more DSBs in H1299 cells. Second, p53 defect and no available induction of DNA repair protein p53R2 impair DNA repair activity in H1299 cells more severely than A549 cells. Third, cleavage of PARP-1 inhibits topoisomerase I and/or topoisomerase I-like activity of PARP-1, aggravates DNA DSBs and DNA repair mechanism impairment in H1299 cells. Together, DDR pathway heterogeneity of cancer cells is linked to cancer susceptibility to DNA damage-based chemotherapeutics, which may provide aid in design of chemotherapy strategy to improve treatment outcomes.

Bexarotene inhibits the viability of non-small cell lung cancer cells via slc10a2/PPARγ/PTEN/mTOR signaling pathway.

BACKGROUND: Thirty to 40 % of non-small cell lung cancer (NSCLC) patients developed higher hypertriglyceridemia in the process of treatment with bexarotene. And bioinformatics studies discovered that the expression of slc10a2 was increased in high-grade hypertriglyceridemia patients. So, we will explore the mechanism which may involve in this process. METHODS: We constructed slc10a2 overexpressed A549 cells and H1299 cells as cell models, normal A549 cells and H1299 cells as control. Then we explored the effects of slc10a2 on A549 cells and H1299 cells behaviors, including proliferation, invasion and apoptosis. The expression of apoptotic related genes and anti-cancer genes also been detected. RESULTS: We found that the proliferation and migration were inhibited and the apoptosis of NSCLC cells was accelerated by bexarotene. In addition, overexpressed slc10a2 in NSCLC cells can further suppress the proliferation and migration, and promote apoptosis under the treatment of bexarotene. On the contrary, the opposite results were obtained after slc10a2 gene was silenced in NSCLC cells treated with bexarotene. Moreover, the expression of caspase 3, caspase 7, PTEN, P21, P53, LKB1, TSC2 were increased and the expression of Bcl-2, cyclin D1, c-FLIP were declined in NSCLC cells and slc10a2 overexpressed NSCLC cells with the treatment of bexarotene, and the opposite situations were seen after slc10a2 gene was silenced in NSCLC cells. The further studies revealed the increased expression of slc10a2 activated the expression of peroxisome proliferator-activated receptor γ (PPARγ), then up-regulated PTEN expression and down-regulated mTOR expression. CONCLUSION: These results suggest that bexarotene inhibits the viability of lung cancer cells via slc10a2/PPARγ/PTEN/mTOR signaling pathway.

Oncolytic E1B 55KDa-deleted adenovirus replication is independent of p53 levels in cancer cells.

Oncolytic adenoviruses represent a new approach for cancer therapy due to its tumor specificity. E1B 55kDa-deleted adenovirus type 5 (Ad5dlE1B 55kDa) is a promising therapeutic agent that can selectively replicate in and lyse p53 defective cancer cells. However, the overall efficacy has shown varying degrees of success with raised doubts about the correlation between p53 status and E1B-deleted adenovirus replication ability. In this study, we investigated the relationship between the efficiency of Ad5dlE1B 55kDa replication and p53 levels in cancer cells. Five transient p53 expression vectors were engineered to expresses different p53 levels in transfected cells. Then, the effect of the variable p53 levels and cellular backgrounds on the replication efficiency of oncolytic Ad5dlE1B 55kDa was evaluated in H1299 and HeLa cell lines. We found that the replication efficiency of these oncolytic viruses is dependent on the status, but not the expression levels, of p53. Ad5dlE1B 55kDa was shown to have selective replication activity in H1299 cells (p53-null) and decreased viral replication in HeLa cells (p53-positive), relative to the wild-type adenovirus in both cell lines. Our findings suggest that there is a relation between the E1B-deleted adenovirus replication and the presence as well as the activity of p53, independent of its quantity.

PKCα-GSK3ß-NF-κB signaling pathway and the possible involvement of TRIM21 in TRAIL-induced apoptosis.

Tumor necrosis factor related apoptosis-inducing ligand (TRAIL) is a highly promising therapeutic agent for cancer treatment, owing to its ability to selectively target tumor cells for cell death while having little effect on most normal cells. However, recent research has found that many cancers, including non-small cell lung cancer (NSCLC), display resistance to TRAIL. Therefore, it is important to elucidate the molecular mechanisms governing the resistance of tumor cells to TRAIL treatment. In this study, we show that GSK3ß antagonized TRAIL-induced apoptosis in H1299 NSCLC cells, and determined that the PKCα isozyme is an upstream regulator of GSK3ß that phosphorylates and inactivates GSK3ß, thereby sensitizing cancer cells to TRAIL-induced apoptosis. Furthermore, we demonstrated that the anti-apoptotic effect of GSK3ß is mediated by the NF-κB pathway, whereas the tripartite motif 21 (TRIM21) was able to inhibit the activation of NF-κB by GSK3ß, and leads to the promotion of cell apoptosis. Taken together, our study further delineated the underpinning mechanism of resistance to TRAIL-induced apoptosis in H1299 cells, and provided new clues for sensitizing NSCLC cells to TRAIL therapy.