Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0684249 (lung carcinoma)
 23,830 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The recovery of the enzyme poly(ADP-ribose) polymerase (pADPRp) in the nuclease- and 1.6 M NaCl-resistant nuclear subfraction prepared from a number of different sources was assessed by Western blotting. When rat liver nuclei were treated with DNase I and RNase A followed by 1.6 M NaCl, approximately 10% of the nuclear pADPRp was recovered in the sedimentable fraction. The proportion of pADPRp recovered with the residual fraction decreased to less than 5% of the total nuclear polymerase when nuclei were prepared in the presence of the sulfhydryl blocking reagent iodoacetamide and increased to approximately 50% of the total nuclear pADPRp when nuclei were treated with the sulfhydryl cross-linking reagent sodium tetrathionate (NaTT) prior to fractionation. To determine whether this effect of disulfide bond formation was unique to rat liver nuclei, nuclear matrix/cytoskeleton structures were prepared in situ by sequentially treating monolayers of tissue culture cells with Nonidet-P40, DNase I and RNase A, and 1.6 M NaCl (S.H. Kaufmann and J.H. Shaper (1991) Exp. Cell Res. 192, 511-523). When nuclear monolayers were prepared from HTC rat hepatoma cells, CaLu-1 human lung carcinoma cells, and CHO hamster ovary cells in the absence of NaTT, pADPRp was undetectable in the nuclease- and 1.6 M NaCl-resistant fraction. In contrast, when nuclear monolayers were isolated in the presence of NaTT, from 5% (CaLu-1) to 26% (HTC cells) of the total nuclear pADPRp was recovered with the nuclease- and salt-resistant fraction. Examination of these residual structures by SDS-polyacrylamide gel electrophoresis under nonreducing conditions suggested that pADPRp was present as a component of disulfide cross-linked complexes. Further analysis by immunofluorescence revealed that the pADPRp was diffusely distributed throughout the CaLu-1 or CHO nuclear matrix. In addition, when matrices were prepared in the absence of RNase A, pADPRp was also observed in the residual nucleoli. These observations reveal that the recovery of pADPRp with a nuclease- and salt-resistant nuclear subfraction is dependent on the source of the nuclei and on the conditions used to fractionate those nuclei. In addition, these observations raise the possibility that there might be different functional classes of pADPRp molecules within the nucleus.
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PMID:Association of poly(ADP-ribose) polymerase with the nuclear matrix: the role of intermolecular disulfide bond formation, RNA retention, and cell type. 170 86

The lamins, an intranuclear class of intermediate filament proteins, are major structural proteins of the nuclear envelope. In the present study, the three abundant mammalian lamins (lamins A, B, and C) were observed to be present in roughly equivalent amounts in the Calu-1, Calu-3, H157, and SK-MES-1 non-small cell lung cancer lines. In the small cell lung cancer lines OH-1, OH-3, NCI-H82, NCI-H209, and NCI-H249, levels of lamin B were similar to those observed in the non-small cell lines, but the levels of lamins A and C were diminished by greater than or equal to 80%. The relationship between lung cancer phenotype and lamin expression was explored further in the NCI-H249 small cell line. Introduction of the v-rasH oncogene into this line gives rise to a cell line (NCI-H249rasH) with many features of large cell carcinoma of the lung (Falco, J. P., Baylin, S. B., Lupu, R., et al. J. Clin. Invest., 85: 1740-1745, 1990). Concomitant with the v-rasH-induced change in phenotype, a greater than 10-fold increase in the amounts of lamins A and C was observed. Levels of the cytoplasmic intermediate filament protein vimentin also increased. In contrast, levels of a variety of nonlamin nuclear polypeptides including topoisomerase I, topoisomerase II, poly(ADP-ribose) polymerase, and the nucleolar protein B23/nucleophosmin did not change. Comparison of polyadenylated RNA from NCI-H249 and NCI-H249rasH cells on Northern blots revealed similar levels of the mRNA for lamin B but higher levels of the mRNAs for lamins A and C in the v-rasH-expressing cell line. These observations provide evidence for differences in nuclear envelope structure in histologically different neoplastic cells derived from the same epithelial cell system and suggest that differences in lamina structure result from phenotype-specific differences in lamin gene expression.
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PMID:Differential expression of nuclear envelope lamins A and C in human lung cancer cell lines. 198 76

We have identified the CD95 system as a key mediator of chemotherapy-induced apoptosis in leukemia and neuroblastoma cells. Here, we report that sensitivity of various solid tumor cell lines for drug-induced cell death corresponds to activation of the CD95 system. Upon drug treatment, strong induction of CD95 ligand (CD95-L) and caspase activity were found in chemosensitive tumor cells (Hodgkin, Ewing's sarcoma, colon carcinoma and small cell lung carcinoma) but not in tumor cells which responded poorly to drug treatment (breast carcinoma and renal cell carcinoma). Blockade of CD95 using F(ab')2 anti-CD95 antibody fragments markedly reduced drug-induced apoptosis, suggesting that drug-triggered apoptosis depended on CD95-L/receptor interaction. Moreover, drug treatment induced CD95 expression, thereby increasing sensitivity for CD95-induced apoptosis. Drug-induced apoptosis critically depended on activation of caspases (ICE/Ced-3-like proteases) since the broad-spectrum inhibitor of caspases zVAD-fmk strongly reduced drug-mediated apoptosis. The prototype substrate of caspases, poly(ADP-ribose) polymerase, was cleaved upon drug treatment, suggesting that CD95-L triggered autocrine/paracrine death via activation of caspases. Our data suggest that chemosensitivity of solid tumor cells depends on intact apoptosis pathways involving activation of the CD95 system and processing of caspases. Our findings may have important implications for new treatment approaches to increase sensitivity and to overcome resistance of solid tumors.
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PMID:Chemosensitivity of solid tumor cells in vitro is related to activation of the CD95 system. 953 69

The anti-tumor drug Flavopiridol is a potent inhibitor of cyclin-dependent kinases (cdks). As a consequence, Flavopiridol-treated cells arrest in both G1 and G2, but Flavopiridol has also been shown to be cytotoxic for some tumor cell lines. The underlying molecular events are, however, unclear. We now show that Flavopiridol induces apoptosis in human umbilical vein endothelial cells (HUVECs), as judged by the occurrence of classical apoptotic markers, including chromatin condensation, internucleosomal cleavage, DNA fragmentation (TUNEL assay), annexin V binding and poly(ADP-ribose) polymerase (PARP)-cleavage. Such induction of apoptosis occurs with equal efficiency in both proliferating and G0/G1-arrested cells. Because growth-arrested HUVECs lack cdk2 activity and contain high levels of the cdk inhibitor p27, our observations suggest that cell cycle regulated cdks may not be the only critical target for Flavopiridol-induced apoptosis. Surprisingly, A549 lung carcinoma cells were clearly dependent on cell proliferation for the induction of cell death, pointing to cell type-related differences in the mechanism of Flavopiridol action.
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PMID:Cell cycle-independent induction of apoptosis by the anti-tumor drug Flavopiridol in endothelial cells. 963 6

Activation of signaling pathways after DNA damage induced by topoisomerase (topo) poisons can lead to cell death by apoptosis. Treatment of human nonsmall cell lung carcinoma (NSCLC-3 or NSCLC-5) cells with the topo I poison SN-38 or the topo II poison etoposide (VP-16) leads to activation of NF-kappaB before induction of apoptosis. Inhibiting the degradation of IkappaBalpha by pretreatment with the proteasome inhibitor MG-132 significantly inhibited NF-kappaB activation and apoptosis but not DNA damage induced by SN-38 or VP-16. Transfection of NSCLC-3 or NSCLC-5 cells with dominant negative mutant IkappaBalpha (mIkappaBalpha) inhibited SN-38 or VP-16 induced transcription and DNA binding activity of NF-kappaB without altering drug-induced apoptosis. Regulation of apoptosis by mitochondrial release of cytochrome c and activation of pro-caspase 9 followed by cleavage of poly(ADP-ribose) polymerase by effector caspases 3 and 7 was similar in neo and mIkappaBalpha cells treated with SN-38 or VP-16. In contrast to pretreatment with MG-132, exposure to MG-132 after SN-38 or VP-16 treatment of neo or mIkappaBalpha cells decreased cell cycle arrest in the S/G2 + M fraction and enhanced apoptosis compared with drug alone. In summary, apoptosis induced by topoisomerase poisons in NSCLC cells is not mediated by NF-kappaB but can be manipulated by proteasome inhibitors.
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PMID:Roles of NF-kappaB and 26 S proteasome in apoptotic cell death induced by topoisomerase I and II poisons in human nonsmall cell lung carcinoma. 1111 10

The melanoma differentiation-associated gene-7 (mda-7), cloned from a human melanoma cell line H0-1, is known to induce tumor cell-selective growth inhibition in breast cancer cells in vitro and loss of tumorigenicity ex vivo. Yet, the mechanisms underlying these effects are still unknown. Therefore, we investigated these mechanisms on the molecular level in human non-small cell lung carcinoma (NSCLC) cells in vitro. Overexpression of mda-7 protein by Ad-mda-7 significantly suppressed proliferation and induced G2/M cell cycle arrest in wild-type p53 (A549, H460), and p53-null (H1299) non-small cell lung cancer cell lines, but not in normal human lung fibroblast (NHLF) cells. p53, Bax, and Bak protein expression was up-regulated in wild-type p53 tumor cell lines, but not in p53-null cells, suggesting that an intact p53 pathway was required for Bax and Bak induction. However, in all three cancer cell lines tested, activation of the caspase cascade and cleavage of poly(ADP-ribose) polymerase (PARP) appeared to be independent of the p53 mutational status. Together, these results suggest that apoptosis may be induced via multiple pathways by Ad-mda-7 in lung cancer cells and that Ad-mda-7 has the potential to become a novel therapeutic for clinical cancer gene therapy. Gene Therapy (2000) 7, 2051-2057.
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PMID:Tumor-suppressive effects by adenovirus-mediated mda-7 gene transfer in non-small cell lung cancer cell in vitro. 1117 18

Discodermolide and epothilone B are promising novel chemotherapeutic agentsthat induce cell death through potent stabilization of microtubules. In this study, we investigated the cellular and molecular events underlying the cytotoxicity of these drugs in non-small cell lung carcinoma (NSCLC) cell lines, focusing on apoptotic characteristics. IC80 concentrations of either drug effectively disrupted the microtubule cytoskeleton of H460 cells and induced cell cycle disturbances with early accumulation in the G2-M phase and development of a hypodiploid cell population in both H460 and SW1573 cells. These events were followed by abnormal chromosome segregation during mitosis and subsequent appearance of multinucleated cells. At later time points, the cells displayed several apoptotic features, such as nuclear condensation and fragmentation as well as Annexin V staining, cleavage of poly(ADP-ribose) polymerase and the activation of caspases. To examine the contribution of apoptotic pathways to the cytotoxic effects of these agents, the involvement of the mitochondria and death receptor routes was studied. At 48 h after treatment, both agents disrupted mitochondria of H460 cells, as indicated by cytochrome c release. Nonetheless, H460 cells stably overexpressing antiapoptotic Bcl-2 or Bcl-xL did not show any protective effect from cell death induced by either drug. Possible death receptor dependency was investigated in H460 cells stably overexpressing dominant-negative FADD, which failed to reduce the cytotoxic effects of discodermolide and epothilone B. To study the role of caspases more directly, the effect of stable overexpression of the caspase-8 inhibitor cytokine response modifier A was studied in H460 cells. Furthermore, the effect of the pancaspase inhibitor z-Val-Ala-Asp-fluoromethyl ketone was investigated in a panel of lung carcinoma cell lines. Interestingly, caspase inhibition did not rescue cells from discodermolide or epothilone B-induced cell death. In conclusion, these results demonstrate that despite several apoptotic features detected at relatively late time points after drug exposure, apoptosis is not the dominant mode of cell death and induced low but efficacious concentrations of discodermolide and epothilone B.
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PMID:Late activation of apoptotic pathways plays a negligible role in mediating the cytotoxic effects of discodermolide and epothilone B in non-small cell lung cancer cells. 1212 45

Lung cancer continues to be the leading cause of cancer-related death in the United States. Therefore, new agents targeting prevention and treatment of lung cancer are urgently needed. In the present study, we demonstrate that a novel synthetic triterpenoid methyl-2-cyano-3,12-dioxooleana-1,9-dien-28-oate (CDDO-Me) is a potent inducer of apoptosis in human non-small cell lung carcinoma (NSCLC) cells. The concentrations required for a 50% decrease in cell survival (IC50) ranged from 0.1 to 0.3 microM. CDDO-Me induced rapid apoptosis and triggered a series of effects associated with apoptosis including a rapid release of cytochrome c from mitochondria, activation of procaspase-9, -7, -6, and -3, and cleavage of poly(ADP-ribose) polymerase and lamin A/C. Moreover, the caspase-3 inhibitor Z-DEVD-FMK and the pan caspase inhibitor Z-VAD-FMK suppressed CDDO-Me-induced apoptosis. These results indicate that CDDO-Me induced apoptosis in human NSCLC cells via a cytochrome c-triggered caspase activation pathway. CDDO-Me did not alter the level of Bcl-2 and Bcl-xL proteins, and no correlation was found between cell sensitivity to CDDO-Me and basal Bcl-2 expression level. Furthermore, overexpression of Bcl-2 did not protect cells from CDDO-Me-induced apoptosis. These results suggest that CDDO-Me induces apoptosis in NSCLC cells irrespective of Bcl-2 expression level. In addition, no correlation was found between cell sensitivity to CDDO-Me and p53 status, suggesting that CDDO-Me induce a p53-independent apoptosis. Our results demonstrate that CDDO-Me may be a good candidate for additional evaluation as a potential therapeutic agent for human lung cancers and possibly other types of cancer.
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PMID:Identification of a novel synthetic triterpenoid, methyl-2-cyano-3,12-dioxooleana-1,9-dien-28-oate, that potently induces caspase-mediated apoptosis in human lung cancer cells. 1246 12

The unique signal transduction pathways that distinguish non-small cell lung carcinoma (NSCLC) from small cell lung carcinoma (SCLC) are poorly understood. We investigated the ability of edelfosine, an inhibitor of phosphatidylinositol-specific phospholipase C (PLC) to inhibit cell viability among four NSCLC cell lines and four SCLC cell lines. The differential sensitivity of cells to edelfosine's cytostatic and cytotoxic effects has been attributed to edelfosine-induced changes in the activities of many enzymes, including c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinases (ERK), p38 kinase, and poly(ADP-ribose) polymerase (PARP). To investigate the role of these enzymes in edelfosine-induced cytotoxicity, we correlated edelfosine-induced changes in enzyme activity and cell viability among the different NSCLC and SCLC cell lines. We found that NSCLC cells are much more susceptible to the cytotoxic effects of this drug than are SCLC cells. Three out of the four edelfosine-sensitive NSCLC cell lines (NCI-H157, NCI-H520, NCI-H522) exhibit G2/M arrest, significant apoptosis and some degree of JNK activation in response to drug treatment. In contrast, none of the SCLC cell lines exhibit edelfosine-induced G2/M arrest or significant apoptosis. A comparison of the edelfosine-induced effects among the sensitive and resistant lung cancer lines indicates that there is little correlation between edelfosine-induced cytotoxicity and altered activities of JNK, ERK, p38, or cleavage of PARP. These results demonstrate that edelfosine-induced changes in JNK, ERK, p38, or PARP are not good predictors of cell susceptibility to edelfosine-induced cytotoxicity. Thus, edelfosine-induced inactivation of PLC may disrupt signaling cascades downstream of PLC that are unique to individual cellular environments. These findings also identify edelfosine as one of the few potential chemotherapeutic agents that has a greater cytotoxic effect against NSCLC cells than SCLC cells.
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PMID:Non-small and small cell lung carcinoma cell lines exhibit cell type-specific sensitivity to edelfosine-induced cell death and different cell line-specific responses to edelfosine treatment. 1285 88

Glycation of nucleotides in DNA forms AGEs (advanced glycation end-products). Nucleotide AGEs are: the imidazopurinone derivative dG-G [3-(2'-deoxyribosyl)-6,7-dihydro-6,7-dihydroxyimidazo[2,3-b]purin-9(8)one], CMdG ( N (2)-carboxymethyldeoxyguanosine) and gdC (5-glycolyldeoxycytidine) derived from glyoxal, dG-MG [6,7-dihydro-6,7-dihydroxy-6-methylimidazo-[2,3-b]purine-9(8)one], dG-MG(2) [ N (2),7-bis-(1-hydroxy-2-oxopropyl)deoxyguanosine] and CEdG [ N (2)-(1-carboxyethyl)deoxyguanosine] derived from methylglyoxal, and dG-3DG [ N (2)-(1-oxo-2,4,5,6-tetrahydroxyhexyl)deoxyguanosine] derived from 3-deoxyglucosone and others. Glyoxal and methylglyoxal induce multi-base deletions, and base-pair substitutions - mostly occurring at G:C sites with G:C-->C:G and G:C-->T:A transversions. Suppression of nucleotide glycation by glyoxalase I and aldehyde reductases and dehydrogenases, and base excision repair, protects and recovers DNA from damaging glycation. The effects of DNA glycation may be most marked in diabetes and uraemia. Mutations arising from DNA glycation may explain the link of non-dietary carbohydrate intake to incidence of colorectal cancer. Overexpression of glyoxalase I was found in drug-resistant tumour cells and may be an example of an undesirable effect of the enzymatic protection against DNA glycation. Experimental overexpression of glyoxalase I conferred resistance to drug-induced apoptosis. Glyoxalase I-mediated drug resistance was found in human leukaemia and lung carcinoma cells. Methylglyoxal-mediated glycation of DNA may contribute to the cytotoxicity of some antitumour agents as a consequence of depletion of NAD(+) by poly(ADP-ribose) polymerase, marked increases in triosephosphate concentration and increased formation of methylglyoxal. S - p -Bromobenzylglutathione cyclopentyl diester is a cell-permeable glyoxalase I inhibitor. It countered drug resistance and was a potent antitumour agent against lung and prostate carcinoma. Glyoxalase I overexpression was also found in invasive ovarian cancer and breast cancer.
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PMID:Protecting the genome: defence against nucleotide glycation and emerging role of glyoxalase I overexpression in multidrug resistance in cancer chemotherapy. 1464 Oct 66


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