mitopodozide and Adenocarcinoma

Surfactant protein B (SP-B) is essential for the maintenance of biophysical properties and physiological function of pulmonary surfactant. Tumor necrosis factor-alpha (TNF-alpha), an important mediator of lung inflammation, inhibits surfactant phospholipid and surfactant protein synthesis in the lung. In the present study, we investigated the TNF-alpha inhibition of rabbit SP-B promoter activity in a human lung adenocarcinoma cell line (NCI-H441). Deletion experiments indicated that the TNF-alpha response elements are located within -236 bp of SP-B 5'-flanking DNA. The TNF-alpha response region contained binding sites for nuclear factor-kappa B (NF-kappa B), Sp1/Sp3, thyroid transcription factor (TTF)-1, and hepatocyte nuclear factor (HNF)-3 transcription factors. Inhibitors of NF-kappa B activation such as dexamethasone and N-tosyl-L-phenylalanine chloromethyl ketone and mutation of the NF-kappa B element did not reverse TNF-alpha inhibition of SP-B promoter, indicating that TNF-alpha inhibition of SP-B promoter activity occurs independently of NF-kappa B activation. TNF-alpha treatment decreased the binding activities of TTF-1 and HNF-3 elements without altering the nuclear levels of TTF-1 and HNF-3 alpha proteins. Pretreatment of cells with okadaic acid reversed TNF-alpha inhibition of SP-B promoter activity. Taken together these data indicated that in NCI-H441 cells 1) TNF-alpha inhibition of SP-B promoter activity may be caused by decreased binding activities of TTF-1 and HNF-3 elements, 2) the decreased binding activities of TTF-1 and HNF-3 alpha are not due to decreased nuclear levels of the proteins, and 3) okadaic acid-sensitive phosphatases may be involved in mediating TNF-alpha inhibition of SP-B promoter activity.

Topics: Adenocarcinoma; Animals; Cell Line; Cell Nucleus; Cytosol; DNA-Binding Proteins; Gene Expression Regulation; Hepatocyte Nuclear Factor 3-alpha; Humans; Lung Neoplasms; Mutagenesis, Site-Directed; NF-kappa B; Nuclear Proteins; Podophyllin; Podophyllotoxin; Promoter Regions, Genetic; Proteolipids; Pulmonary Surfactants; Rabbits; Thyroid Nuclear Factor 1; Transcription Factors; Transfection; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

We studied the effects of bile acids on inducibility of the transcription factor AP-1 in human colon carcinoma LoVo cells. Firstly, cells were treated with chenodeoxycholic acid and the nuclear extracts from those cells were processed by electrophoretic mobility shift assays to analyze nuclear AP-1 DNA-binding activity. We demonstrated that chenodeoxycholic acid induced AP-1 DNA-binding activity in a dose- and time-dependent fashion. Antibody supershift experiments clearly revealed that the majority of protein components in induced AP-1 DNA-binding activity were the products of oncogenes c-fos and c-jun. On the other hand, DNA-binding activity in the nuclear extracts for either NF kappa B, Sp1, or ATF/CREB was not affected by bile acids, suggesting that the effect of bile acids was rather specific for AP-1. Transient transfection experiments supported this notion: expression of the AP-1-luciferase reporter construct was induced by bile acids in a dose-dependent manner, and expression of either reporter construct for NF kappa B, Sp1, or ATF/CREB was not influenced by treatment of the cells with bile acids. We also demonstrated that those bile acids efficiently activated AP-1-dependent promoter in DLD-1 cells, which (as well as LoVo cells), are derived from colon adenocarcinoma, but not in COLO320DM cells which are from colon carcinoid tumor. Thus, we may indicate that bile acids exclusively induce nuclear AP-1 activity in colon adenocarcinoma cells.

Topics: Activating Transcription Factor 1; Adenocarcinoma; Base Sequence; Bile Acids and Salts; Chenodeoxycholic Acid; Cholagogues and Choleretics; Cholic Acid; Cholic Acids; Colonic Neoplasms; Deoxycholic Acid; DNA Primers; DNA-Binding Proteins; DNA, Neoplasm; Enzyme Activation; Gene Expression Regulation; Genetic Vectors; Humans; Lithocholic Acid; Molecular Sequence Data; NF-kappa B; Podophyllin; Podophyllotoxin; Protein Kinase C; Tetradecanoylphorbol Acetate; Transcription Factor AP-1; Transcription Factors; Tumor Cells, Cultured; Ursodeoxycholic Acid

Two patients with lung metastases are presented who were submitted to a combined low-dose radiotherapy and adriamycin monotherapy with good palliative results. The mode of action as well as the experimental examination results are discussed. The ineffectiveness of single low-dose chemotherapy is demonstrated by the non-response of lung metastases beyond the irradiation fields (heart block, diaphragm). Both patients were resistant to chemotherapy.

Topics: Adenocarcinoma; Aged; Carcinoma; Cobalt Radioisotopes; Combined Modality Therapy; Cyclophosphamide; Doxorubicin; Female; Humans; Hysterectomy; Lung Neoplasms; Male; Methotrexate; Middle Aged; Podophyllin; Podophyllotoxin; Radioisotope Teletherapy; Uterine Neoplasms