Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0242379 (lung cancer)
 71,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bcl-XL is overexpressed in a variety of human tumors and is involved in tumorigenesis and chemoresistance. This study investigated the inhibitory effect of the hairpin Bcl-XL small interfering RNA (siRNA) on the expression of the Bcl-XL gene in the cisplatin (DDP)-resistant human lung adenocarcinoma cell line A549/DDP, and the effect of Bcl-XL siRNA on drug sensitization in A549/DDP cells. Bcl-XL siRNA and negative siRNA plasmids were constructed and stably transfected into A549/DDP cells. Reverse transcription-polymerase chain reaction and Western blot analysis were used to detect the target gene expression. Spontaneous apoptosis of cells was detected by acridine orange and ethidium bromide staining. Drug sensitivity of the cells to DDP was analyzed with dimethylthiazol-diphenyltetrazolium bromide (MTT) and flow cytometry. Expression levels of Bcl-XL mRNA and protein in siRNA stable transfectants were clearly reduced as compared with negative siRNA transfectants and untreated cells. MTT results indicated that Bcl-XL transfectants had a higher cell inhibition rate than the negative vector or untreated cells after treatment with 0.2-200 micarog/ml DDP. Flow cytometry revealed increased apoptosis in Bcl-XL siRNA cells. After the addition of 20 microg/ml DDP, siRNA targeting of the Bcl-XL gene specifically down-regulated gene expression in A549/DDP cells, increased spontaneous apoptosis, and sensitized cells to DDP. The results showed that Bcl-XL siRNA contributed to an increase of DDP-induced cell death in non-small-cell lung cancer and sensitized cells to DDP, leading to increased the effectiveness of the drug in treating non-small-cell lung cancer.
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PMID:Bcl-XL small interfering RNA sensitizes cisplatin-resistant human lung adenocarcinoma cells. 1749 31

5-Bromo-2-deoxyuridine (BrdU) is a thymidine analogue that is incorporated into replicating DNA. Although originally designed as a chemotherapeutic agent, sublethal concentrations of BrdU have long been known to alter the growth and phenotype of a wide range of cell types. Mechanisms underlying these BrdU-mediated effects remain unknown, however. We have characterized the effects of BrdU on A549 lung cancer cells by examining DNA damage responses, cell cycle effects and phenotypic changes. A549 cells express wild-type p53, but are p16-null. Sublethal concentrations of BrdU evoke a DNA damage response in these cells that involves the activation of Chk1, Chk2 and p53. Increased numbers of enlarged nuclei and multinucleated cells are evident in the treated populations. Cell cycle inhibition occurs, resulting in reduced proliferation and accumulation of cells in the S, G2/M and G0 phases. BrdU induces an early inhibition of p21 expression that coincides with nuclear localization of proliferating cell nuclear antigen. Subsequently, p21 levels increase, whereas proliferating cell nuclear antigen levels decrease compared with control cells. Upregulation of p27 and p57 expression also occurs. By day 7 of exposure to BrdU, treated cells acquire a senescent-like phenotype with an increase in cell size, granularity and beta-galactosidase activity. We conclude that BrdU induces a DNA damage response in A549 cells, which results in reduced proliferation mitotic exit and phenotypic changes that resemble senescence.
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PMID:5-Bromo-2-deoxyuridine activates DNA damage signalling responses and induces a senescence-like phenotype in p16-null lung cancer cells. 1770 56

The response rates to combination chemotherapy in metastatic non-small cell lung cancer (NSCLC) cases have been reported to be lower than those to induction chemotherapy in locally advanced cases. To understand the relationship between highly metastatic potential and chemosensitivity, we examined the drug sensitivity of a highly metastatic human lung adenocarcinoma cell subpopulation, PC9/f14, which had been previously established in an experimental metastasis model, to commonly used anti-cancer agents (paclitaxel, SN38, gemcitabine, vindesine, etoposide, cisplatin, and carboplatin) via the 3-(4, 5-dimethylthiazol-2-yl)2, 5-diphenyltetrazolium bromide assay. We found that the PC9/f14 subpopulation, which we previously reported to be resistant to gefitinib, was also resistant to gemcitabine (2',2'-difluoro-2'-deoxy-cytidine), a nucleoside analogue. To clarify the mechanisms of the gemcitabine resistance in this subpopulation, we screened the changes to the protein expression profiles of these cells after exposure to gemcitabine, using a 224-antibody microarray analysis. The exposure to gemcitabine in this subpopulation induced an increase in the expression level of the Bcl-X protein, although this expression remained unchanged in the parent cells. Apoptosis following gemcitabine exposure was depressed in the PC9/f14 subpopulation compared with parent cells, as assessed by flow cytometry and TUNEL assay. In addition, knock-down of Bcl-X by RNA interference methodology induced the recovery of gemcitabine sensitivity in PC9/f14. Phosphorylated Akt, which seems to be involved in the gefitinib resistance of this subpopulation, did not change after gemcitabine exposure. In conclusion, this highly metastatic lung cancer subpopulation had multi-resistant characteristics, to both gemcitabine and gefitinib, which were achieved in different ways, during the process of obtaining its highly metastatic potential. The combination of anti-cancer drugs and inhibition of the molecules related with apoptosis and/or Akt pathway might be beneficial in the treatment of metastatic NSCLC.
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PMID:Gemcitabine resistance in a highly metastatic subpopulation of a pulmonary adenocarcinoma cell line resistant to gefitinib. 1798 58

This study explores perfluorooctyl bromide (PFOB) as a potential vehicle for the pulmonary delivery of a series of prodrugs of nicotinic acid using cell culture studies. The prodrugs investigated have PFOB-water (logK(p)=0.78 to >2.2), perfluoromethylcyclohexane-toluene (logK(p)=-2.62 to 0.13) and octanol-water (logK(p)=0.90-10.2) partition coefficients spanning several orders of magnitude. In confluent NCI-H358 human lung cancer cells, the toxicity of prodrugs administered in culture medium or PFOB depends on the medium of administration, with EC20's above 8 mM and 2.5 mM for culture medium and PFOB, respectively. Short-chain nicotinates administered both in PFOB and medium increase cellular NAD/NADP levels at 1mM nicotinate concentrations. Long-chain nicotinates, which could not be administered in medium due to their poor aqueous solubility, increased NAD/NADP levels if administered in PFOB at concentrations > or =10 mM. These findings suggest that even highly lipophilic prodrugs can partition out of the PFOB phase into cells, where nicotinic acid is released and converted to NAD. Thus, PFOB may be a novel and biocompatible vehicle for the delivery of lipophilic prodrugs of nicotinic acid and other drugs directly to the lung of laboratory animals and humans.
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PMID:Synthesis, physicochemical properties and in vitro cytotoxicity of nicotinic acid ester prodrugs intended for pulmonary delivery using perfluorooctyl bromide as vehicle. 1816 63

Five active compounds that inhibit cancer cells were isolated from adlay bran (Coix lachryma-jobi L. var. ma-yuen Stapf), and their structures and activities in vitro were characterized. The ethyl acetate-soluble fraction of methanol extracts of adlay bran (ABM-EtOAc) exhibited a stronger anti-proliferative effect on human lung cancer cell A549, human colorectal carcinoma cell HT-29, and COLO 205 than other fractions by MTT (3-4,5-dimethylthiazol-2-yl-2,5-diphenyl-tetrazolium bromide) assay. Assay-guided isolation gave five lactams including three that were previously undocumented; coixspirolactam A (1), coixspirolactam B (2), and coixspirolactam C (3); one isolated from the natural plant for the first time, coixlactam (4); and one known compound, methyl dioxindole-3-acetate (5). Pure active compounds were identified by spectral analysis including IR, 1H and 13C NMR, UV-vis, MS and 2D NMR techniques. All the compounds were tested for their anti-proliferative effect on A549, HT-29 and COLO 205 cells. These compounds showed anti-cancer activities with IC50 values between 28.6 and 72.6microg/mL.
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PMID:Isolation and characterization of new lactam compounds that inhibit lung and colon cancer cells from adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) bran. 1833 75

Dendritic cells (DCs) are important cells in initiating an immune response. A generation of functional DCs has potential clinical use in treating cancer. However, the source of DCs and patient immunodeficiency with cancer have been hindrances in clinical therapy. We generated DCs from human umbilical cord blood mononuclear cells (UBMCs) with recombinant human granulocyte-macrophage colony stimulating factor, recombinant human interleukin-4, and recombinant human tumor necrosis factor-alpha. The mature DC-A549 lung cancer vaccine (AgL-DC) was prepared through loading A549 lysate, treating with lipopolysaccharide (LPS) and positive selecting with CD83 magnetic beads. AgL-DC can secrete interleukin (IL)-12 and IL-1. Further in vitro analysis showed that AgL-DC notably induced human UBMC lymphocyte proliferation (p < 0.01) by 3-(4,5-dimethylthiazol-z-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, increased the cytotoxic T-lymphocyte (CTL) activity of UBMC lymphocytes against A549 cells (p < 0.05, at effector cells:target cells ratios of 50:1 and 100:1) by lactate dehydrogenase (LDH) cytotoxic assay, and improved production of IL-6 and tumor necrosis factor-beta (p < 0.01, p < 0.05) by enzyme-linked immunosorbent assay. Subsequently, the reconstitute immunity model in severe combined immunodeficiencies (SCID) mice has been established using human UBMC transplantation, and similar trends to results of UBMC in vitro experiments have been shown in lymphocyte proliferation, CTL activity, and IL-6 and tumor necrosis factor-beta secretion levels in these models. AgL-DC also significantly (p < 0.01) increased the antitumor effect in vivo. The tumor infiltrating immunocytes were positively expressed human CD83 and CD3 molecules, and they were negatively expressed in tumor tissue treated with control. These results have demonstrated that umbilical cord DCs are a useful source of vaccine cells for augmenting CTL-mediated cytotoxicity and have potential usefulness in cellular therapy for human cancer in a new vaccination strategy.
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PMID:Antitumor effect of lung cancer vaccine with umbilical blood dendritic cells in reconstituted SCID mice. 1859 65

Nitric oxide ((.)NO) induces apoptosis at high concentrations by S-nitrosating proteins such as glyceraldehyde-3-phosphate dehydrogenase. This literature analysis revealed that failure to sustain high (.)NO concentrations is common to all cancers. In cervical, gastric, colorectal, breast, and lung cancer, the cause of this failure is the inadequate expression of inducible nitric oxide synthase (iNOS), resulting from the inhibition of iNOS expression by TGF-beta1 at the mRNA level. In bladder, renal, and prostate cancer, the reason for the insufficient (.)NO levels is the depletion of arginine, resulting from arginase overexpression. Arginase competes with iNOS for arginine, catalyzing its hydrolysis to ornithine and urea. In gliomas and ovarian sarcomas, low (.)NO levels are caused by inhibition of iNOS by N-chlorotaurine, produced by infiltrating neutrophils. Stimulated neutrophils express myeloperoxidase, catalyzing H2O2 oxidation of Cl- to HOCl, which N-chlorinates taurine at its concentration of 19 mM in neutrophils. In squamous cell carcinomas of the skin, ovarian cancers, lymphomas, Hodgkin's disease, and breast cancers, low (.)NO concentrations arise from the inhibition of iNOS by N-bromotaurine, produced by eosinophil-peroxidase-expressing infiltrating eosinophils. Eosinophil peroxidase catalyzes the H2O2 oxidation of Br- to HOBr, which N-brominates taurine to N-bromotaurine at its concentration of 15 mM in eosinophils. In microvascularized tumors, the (.)NO concentration is further depleted; (.)NO is rapidly consumed by red blood cells (RBCs) through S-nitrosation of RBC glutathione and hemoglobin, and by oxidation to nitrate by RBC oxyhemoglobin. Angiogenesis-inhibiting antibodies are currently used to treat cancers; their mode of action is not, as previously thought, reduction of the tumor O2 or nutrient supply. They actually decrease the loss of (.)NO to RBCs.
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PMID:Apoptosis-inducing high (.)NO concentrations are not sustained either in nascent or in developed cancers. 1875 45

1-(2-Methoxyethyl)-2-methyl-4,9-dioxo-3-(pyrazin-2-ylmethyl)-4,9-dihydro-1H-naphtho[2,3-d]imidazolium bromide (YM155 monobromide) is a novel small-molecule survivin suppressant that induces the down-regulation of survivin and exhibits potent antitumor activity in nude mice bearing the human hormone refractory prostate carcinoma cell line PC-3. In this study, radioluminographic determination of the in vivo distribution of radioactivity after administration of [(14)C]YM155 to PC-3-xenografted nude mice revealed a relatively high level of radioactivity in the PC-3 xenograft. Therefore, the uptake of [(14)C]YM155 was further characterized in vitro using PC-3, lung cancer (Calu-6 and NCI-H358), malignant melanoma (A375 and SK-MEL-5), and non-Hodgkin's lymphoma (RL and Ramos) cell lines. The uptake of [(14)C]YM155 in these cell lines was dependent on incubation time, temperature, and drug concentration. The Michaelis-Menten constant values were similar among the seven cell lines (0.189-0.367 microM). The effects of various compounds on the uptake of [(14)C]YM155 were tested in PC-3, Calu-6, A375, RL, and Ramos cell lines. Of the compounds tested, the cationic transporter substrates/inhibitors (tetraethylammonium, 1-methyl-4-phenylpyridium, cimetidine, prazosin, corticosterone, verapamil, amantadine, procainamide, and N-methylnicotinamide) inhibited the uptake of [(14)C]YM155 to a similar extent among the five cell lines. The half-maximal inhibitory concentration values (IC(50)) of several compounds for the uptake of [(14)C]YM155 into PC-3 differed from those reported in the literature for human organic cation transporter 1 (OCT1/SLC22A1), OCT2 (SLC22A2), and OCT3 (SLC22A3). To summarize, YM155 was taken up into cancer cells in a carrier-mediated manner and with a similar affinity among all the cancer cell lines tested. An influx transporter(s) may contribute to this process.
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PMID:Carrier-mediated uptake of 1-(2-methoxyethyl)-2-methyl-4,9-dioxo-3-(pyrazin-2-ylmethyl)-4,9-dihydro-1H-naphtho[2,3-d]imidazolium bromide (YM155 monobromide), a novel small-molecule survivin suppressant, into human solid tumor and lymphoma cells. 1905 13

Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants produced in the combustion of organic matter. PAHs are present in automobile exhaust and tobacco smoke, and they have recently been designated as human carcinogens. Current evidence indicates that PAHs are activated enzymatically to mutagenic metabolites that interact with DNA. There is evidence for three pathways of activation: the diol epoxide path, the radical-cation path, and the quinone path. The relative importance of these paths for human lung cancer has not been established. We now report syntheses of the principal phenol and quinone isomers of the prototype PAH carcinogen benzo[a]pyrene (BP) that are known or are suspected to be formed as metabolites of BP in human bronchoalveolar cells. The methods of synthesis were designed to be adaptable to the preparation of the (13)C-labeled analogues of the BP metabolites. These compounds are needed as standards for sensitive LC-MS/MS methods for analysis of BP metabolites formed in lung cells. Efficient novel syntheses of the 1-, 3-, 6-, 9-, and 12-BP phenols and the BP 1,6-, 3,6-, 6,12-, and 9,10-quinones are now reported. The syntheses of the BP phenols (except 6-HO-BP) involve the key steps of Pd-catalyzed Suzuki-Miyaura cross-coupling of a naphthalene boronate ester with a substituted aryl bromide or triflate ester. The BP quinones were synthesized from the corresponding BP phenols by direct oxidation with the hypervalent iodine reagents IBX or TBI. These reagents exhibited different regiospecificities. IBX oxidation of the 7- and 9-BP phenols provided the ortho-quinone isomers (BP 7,8- and 9,10-diones, respectively), whereas TBI oxidation of the 1-, 3-, and 12-BP phenols furnished BP quinone isomers with carbonyl functions in separate rings (BP 1,6-, 3,6-, and 6,12-diones, respectively).
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PMID:Synthesis of phenol and quinone metabolites of benzo[a]pyrene, a carcinogenic component of tobacco smoke implicated in lung cancer. 1913 42

Erlotinib (Tarceva) targets the epidermal growth factor receptor (EGFR), which is commonly overexpressed in human cancers, including lung cancer. We show that erlotinib can be labeled with [(11)C] by reacting the normethyl precursor with [(11)C]-methyl iodide. By using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide proliferation assay, two lung cancer cell lines (A549 and NCI358) were shown to be less sensitive to erlotinib compared with the lung cancer cell line HCC827. This correlated with higher expression and activity of the EGFR in HCC827 cells as compared with the less sensitive cell lines. Micro-positron emission tomography (PET) and biodistribution of erlotinib was performed with [(11)C]-erlotinib in nude mice bearing xenografts of A549, NCI358, and HCC827 cells. Dynamic micro-PET showed that HCC827 tumors had the highest [(11)C]-erlotinib uptake and retained the activity significantly longer as compared with A549 and NCI358 tumors. Biodistribution of [(11)C]-erlotinib in the xenograft models of lung cancer showed the highest accumulation in the liver. In mice carrying the sensitive cancer cells, the accumulation of [(11)C]-erlotinib was higher in tumors than in the other organs. In contrast, the drug accumulated to a comparable extent in tumors from the less sensitive cancer cells and the other organs. Uptake of [(11)C]-erlotinib in the tumors was 1.6%, 0.7%, and 3.7% (percentage of injected dose/g), in A549, NCI358, and HCC827 cells, respectively. We show for the first time that [(11)C]-erlotinib identifies erlotinib-sensitive tumors. These results pave the road for studies examining the benefit of [(11)C]-erlotinib PET in patients with lung tumors or other tumors overexpressing EGFR.
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PMID:Positron emission tomography (PET) imaging with [11C]-labeled erlotinib: a micro-PET study on mice with lung tumor xenografts. 1915 97


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