salicylates and Colonic-Neoplasms

Potent selective cyclooxygenase-2 (COX-2) inhibitors are effective in controlling inflammatory disorders but are associated with cardiovascular complications. Their clinical use has been severely limited. We propose that transcription-based inhibition of COX-2 expression represents a therapeutic strategy that may circumvent the undesired complications of COX-2 inhibitors. Reported data from several laboratories including ours have identified C/EBPbeta as a key transactivator mediating COX-2 transcriptional activation induced by diverse pro-inflammatory mediators. Results from our recent work show that sodium salicylate at pharmacological concentrations inhibits C/EBPbeta binding to COX-2 promoter by direct inhibition of p90 ribosomal S6 kinase (RSK). RSK phosphorylates C/EBPbeta and stimulates its binding to enhancer elements. We propose that RSK1/2 is a potential target for screening drugs with novel anti-inflammatory and anti-neoplastic therapeutic potentials.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; CCAAT-Enhancer-Binding Protein-beta; Colonic Neoplasms; Cyclooxygenase 2; Gene Expression Regulation, Enzymologic; Genetic Therapy; Humans; Inflammation; Phosphorylation; Promoter Regions, Genetic; Protein Kinase Inhibitors; Ribosomal Protein S6 Kinases, 90-kDa; RNA Interference; RNA, Small Interfering; Salicylates; Transcription, Genetic; Transcriptional Activation

Lichen extracts containing, among other compounds, depsides such as evernic acid, atranorin, and lecanoric acid possess anti-proliferative effects. We aimed to identify lichen metabolites that are responsible for the observed anti-proliferative effects. We performed cytotoxicity, cell colony, cell cycle and apoptosis assays in various cell lines or primary immune cells. We analyzed several cell cycle proteins and apoptosis-related proteins to gain insights into the underlying mechanism. All depsides reduced the viability of the tested cell lines (HCT-116, HEK293T, HeLa, NIH3T3, RAW246.7) in a cell line-dependent manner with lecanoric acid being the most effective. Atranorin did not influence the cell cycle or colony formation in HCT-116 cells, but induced apoptosis in HCT-116 cells. Evernic acid showed no anti-proliferative effects. Lecanoric acid inhibited cell colony formation already at 0.03 µg/ml in HCT-116 cells and induced a G2 cell cycle block in several cell lines. Moreover, lecanoric acid arrested the cell cycle, presumably in the M phase, since expression of cyclin B1 and phosphorylated histone H3 was upregulated, whereas the inactive cyclin-dependent kinase 1 (CDK1) was reduced in HCT-116 cells. Most importantly, cell death induced by lecanoric acid was more prominent in cancer cells than in primary human immune and endothelial cells. In conclusion, lecanoric acid seems to mediate its anti-proliferative effects via arrest of cells in the M phase. Our data suggest lecanoric acid may be a potential new candidate for anti-cancer therapy, because it has anti-proliferative effects on cancer cell lines, and does not affect primary immune cells.

Topics: Animals; Antineoplastic Agents; Apoptosis; CDC2 Protein Kinase; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Cyclin B1; Endothelial Cells; HEK293 Cells; Histones; Humans; Hydroxybenzoates; Lichens; Mice; Mitosis; NIH 3T3 Cells; Salicylates

Topics: Apoptosis; Autophagy; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Humans; Reactive Oxygen Species; Salicylates

Topics: Antineoplastic Agents; Benzofurans; Cell Cycle Checkpoints; Cell Proliferation; Cell Survival; Colonic Neoplasms; Depsides; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Female; Gene Expression Regulation, Neoplastic; HCT116 Cells; HeLa Cells; Humans; Hydroxybenzoates; Lactones; Lichens; Molecular Structure; Poly(ADP-ribose) Polymerases; Proto-Oncogene Proteins c-bcl-2; Salicylates; Uterine Cervical Neoplasms

A known (1) and a structurally related new natural product (2), both belonging to the amorfrutin benzoic acid class, were isolated from the roots of Glycyrrhiza foetida. Compound 1 (amorfrutin B) is an efficient agonist of the nuclear peroxisome proliferator activated receptor (PPAR) gamma and of other PPAR subtypes. Compound 2 (amorfrutin C) showed comparably lower PPAR activation potential. Amorfrutin C exhibited striking antiproliferative effects for human colorectal cancer cells (HT-29 and T84), prostate cancer (PC-3), and breast cancer (MCF7) cells (IC50 values ranging from 8 to 16 μM in these cancer cell lines). Notably, amorfrutin C (2) showed less potent antiproliferative effects in primary colon cells. For HT-29 cells, compound 2 induced G0/G1 cell cycle arrest and modulated protein expression of key cell cycle modulators. Amorfrutin C further induced apoptotic events in HT-29 cells, including caspase activation, DNA fragmentation, PARP cleavage, phosphatidylserine externalization, and formation of reactive oxygen species. Mechanistic studies revealed that 2 disrupts the mitochondrial integrity by depolarization of the mitochondrial membrane (IC50 0.6 μM) and permanent opening of the mitochondrial permeability transition pore, leading to increased mitochondrial oxygen consumption and extracellular acidification. Structure-activity-relationship experiments revealed the carboxylic acid and the hydroxy group residues of 2 as fundamental structural requirements for inducing these apoptotic effects. Synergy analyses demonstrated stimulation of the death receptor signaling pathway. Taken together, amorfrutin C (2) represents a promising lead for the development of anticancer drugs.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; bcl-2-Associated X Protein; Caspases; Cell Cycle Checkpoints; Cell Proliferation; Colonic Neoplasms; Drug Screening Assays, Antitumor; Female; G1 Phase Cell Cycle Checkpoints; Glycyrrhiza; HT29 Cells; Humans; Inhibitory Concentration 50; Male; Membrane Potential, Mitochondrial; Mitochondria; Molecular Structure; Morocco; Peroxisome Proliferator-Activated Receptors; Plant Roots; Reactive Oxygen Species; Salicylates; Structure-Activity Relationship

Histone deacetylase (HDAC) inhibitors, such as valproic acid (VPA), constitute a novel class of anticancer agents that cause an increase in acetylated histones and thus restore the expression of dormant tumor-suppressor and other genes related to cell differentiation, cell-cycle arrest or apoptosis of tumor cells. The Ras inhibitor farnesylthiosalicylic acid (FTS, salirasib) attenuates cancer cell proliferation in vitro and in vivo and, under certain circumstances, induces cell death. FTS by itself does not induce differentiation or complete growth arrest. The abovementioned activity of VPA as a differentiation agent suggested that it might be worth investigating its possible therapeutic potential in synergistic combination with FTS. Here, we examined whether the combined application of VPA and FTS could synergistically inhibit the proliferation of cancer cells that express oncogenic K-Ras (A549 nonsmall-cell lung carcinoma cells), DLD1 (colon carcinoma cells) or chronically active wild-type K-Ras and constitutively active B-Raf (ARO, thyroid carcinoma cells). The results showed that combined treatment with VPA and FTS synergistically reduces proliferation in all of these cancer cell lines by downregulating Ras and blocking the expression of Survivin and Aurora A. These alterations, which were most pronounced following the combined treatment, led to a mitotic crisis, as reflected by mislocalization of the chromosomal passenger complex. Our findings thus demonstrate that combination therapy with VPA and FTS might offer a promising therapeutic approach to the treatment of epithelial tumors.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Aurora Kinases; Blotting, Western; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Cell Division; Cell Line, Tumor; Colonic Neoplasms; Down-Regulation; Farnesol; Flow Cytometry; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Inhibitor of Apoptosis Proteins; Lung Neoplasms; Microtubule-Associated Proteins; Protein Serine-Threonine Kinases; Reverse Transcriptase Polymerase Chain Reaction; RNA, Neoplasm; Salicylates; Survivin; Valproic Acid

Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Blood Glucose; Bone Density Conservation Agents; Chemotherapy, Adjuvant; Colonic Neoplasms; Diabetes Mellitus, Type 2; Diphosphonates; Drug Therapy; Dyslipidemias; Enoxaparin; Fibrinolytic Agents; Fractures, Bone; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Hypolipidemic Agents; Imidazoles; Middle Aged; Neoplasm Staging; Pharmacy; Pyrazoles; Pyridones; Salicylates; Treatment Outcome; Venous Thromboembolism; Young Adult; Zoledronic Acid

We developed N,N'-bis(salicylidene)-1,2-phenylenediamine (salophene, 1) as a chelating agent for metal ions such as Mn(II/III), Fe(II/III), Co(II), Ni(II), Cu(II), and Zn(II). The resulting complexes, from which owing to the carrier ligand a selective mode of action is assumed, were tested for antiproliferative effects on the MCF-7 breast cancer cell line. The cytotoxicity in this assay depended on the nature of the transition metal used. Iron complexes in oxidation states +II and +III (3, 4) strongly reduced cell proliferation in a concentration-dependent manner, whereas, e.g., the manganese analogues 5 and 6 were only marginally active. Therefore, the [N,N'-bis(salicylidene)-1,2-phenylenediamine]iron(II/III) complexes 3 and 4 were selected for studies on the mode of action. Both complexes possessed high activity against various tumor cells, for instance, MDA-MB-231 mammary carcinoma cells as well as HT-29 colon carcinoma cells. They were able to generate reactive oxygen species, showed DNA binding, and induced apoptosis. Exchange of 1 by N,N'-bis(salicylidene)-1,2-cyclohexanediamine (saldach, 2) yielding complexes 7 and 8 reduced the in vitro effects drastically. An unequivocal mode of action cannot be deduced from these results, but it seems to be very likely that cell death is caused by interference with more than one intracellular target.

Topics: Adenocarcinoma; Animals; Apoptosis; Breast Neoplasms; Carcinoma; Cattle; Cell Line, Tumor; Chelating Agents; Circular Dichroism; Colonic Neoplasms; DNA; Electric Impedance; Female; Humans; Metals; Oxidation-Reduction; Oxygen Consumption; Reactive Oxygen Species; Salicylates; Thymus Gland

Recently, there have been extensive efforts to evaluate the chemopreventive role of substances present in natural products. The aim of this study was to examine the effects of the main groups of compounds (salicylalcohol derivates, flavonoids, proanthocyanidins), and salicin isolated from willow bark extract BNO 1455 on proliferation and apoptosis in human colon and cancer cells.. We used human colon cyclooxygenase-2 (COX-2)-positive HT 29 and (COX-2)-negative HCT 116 or lung COX-2 proficient A 549 and low COX-2 expressing SW2 cells. After treatment for 72 h with various concentrations of single substances and acetylsalicylic acid (ASA) as control, inhibition of cell growth and cytotoxicity were measured by colorimetric WST-1 assay and propidium iodide uptake by flow cytometry, respectively. Apoptotic cells were identified by annexin V adhesion using flow cytometry.. Studies on dose-dependent effects of BNO 1455 and its fractions showed anti-proliferative activity of all compounds with 50% maximal growth inhibitory concentrations (GI(50)) between 33.3 and 103.3 microg/ml for flavonoids and proanthocyanidins fractions and 50.0-243.0 microg/ml for salicylalcohol derivates and extract. Apoptosis induction was confirmed by annexin V adherence and analysis of cell morphology based on light scattering characteristics using flow cytometry in all cell lines at GI(50).. We showed that willow bark extract BNO 1455 an its fractions inhibit the cell growth and promote apoptosis in human colon and lung cancer cell lines irrespective of their COX-selectivity.

Topics: Apoptosis; Carcinoma, Small Cell; Cell Proliferation; Cell Survival; Colonic Neoplasms; Cyclooxygenase 1; Cyclooxygenase 2; Flavonoids; Flow Cytometry; HT29 Cells; Humans; Lung Neoplasms; Membrane Proteins; Plant Bark; Plant Extracts; Proanthocyanidins; Salicylates; Salix; Tumor Cells, Cultured

Increased intestinal bile acids as a possible consequence of a high fat/meat, low fiber diet are believed to play an important role in the formation of colon cancer. Interactions of bile salts particularly secondary bile acids with different cell components including DNA may contribute to carcinogenesis. To further investigate DNA damage by bile salts, we assessed the effects of a bile salt mixture containing deoxycholate and chenodeoxycholate on base hydroxylation in Chelex-treated DNA from calf thymus as a model of human colonic mucosal DNA in the presence and absence of reactive oxygen metabolites (ROM).. Chelex-treated DNA from calf thymus (to remove residual iron impurities) was incubated with different bile salt concentrations (4 microM, 4.0 mM) (20.0% deoxycholate, 21.0% chenodeoxycholate) in the presence and absence of an OH generating system (25 microM FeCl3, 50 microM H2O2, 100 microM nitrilotriacetic acid) for 18 h (37 degrees C). After hydrolyzation, lyophilization and derivatization hydroxylated DNA bases were characterised and quantitated with gas chromatography-mass spectrometry (GS-MS) and SIM analysis. Two concentration ranges of bile salts were used, micromolar concentrations being present in plasma, millimolar in the gut lumen.. In the absence of ROM Chelex-treated DNA preparations contain only small amounts of hydroxylated base products. Bile salts at 4.0 mM significantly increased the amounts of 5-OH uracil and cis-thymine glycol. In the presence of ROM bile salts at 4.0 microM increased the production of 8-OH adenine and 8-OH guanine whereas bile salts at 4.0 mM inhibited ROM-induced base hydroxylation.. In the absence of ROM millimolar concentrations of a bile salt mixture with deoxycholate and chenodeoxycholate increase basal (spontaneous) DNA hydroxylation, whereas, they are without effects at micromolar concentrations. In the presence of ROM micromolar concentrations enhance oxidative DNA damage and millimolar concentrations were inhibitory. These results support the view that bile acids may cause oxidative DNA damage depending on their concentrations and the surrounding conditions both directly (enhancement of basal hydroxylation) and indirectly (enhancement of ROM-induced hydroxylation).

Topics: Adenine; Animals; Cattle; Chenodeoxycholic Acid; Colon; Colonic Neoplasms; Deoxycholic Acid; DNA; DNA Damage; Gas Chromatography-Mass Spectrometry; Gastrointestinal Agents; Guanine; Humans; Hydroxylation; Intestinal Mucosa; Models, Chemical; Reactive Oxygen Species; Salicylates; Thymus Gland

Topics: Anti-Inflammatory Agents, Non-Steroidal; Aspirin; CCAAT-Enhancer-Binding Protein-beta; Colonic Neoplasms; Cyclooxygenase 1; Cyclooxygenase 2; Humans; Isoenzymes; Membrane Proteins; NF-kappa B; Prostaglandin-Endoperoxide Synthases; Protein Kinase Inhibitors; Salicylates

In colon cancer, K-Ras oncogenes, which appear to be linked to chemoresistance and poor prognosis, are activated in more than 50% of cases, whereas the tumor suppressor gene p53 is mutationally altered in about 70% of all cases. The transcription factor p53, which is frequently mutated at codon 273, maintains wild-type configuration and possibly carries out residual functions. Although blocking of activated K-Ras may constitute a rational therapeutic concept for this treatment-resistant malignancy, a strategy influencing both oncogenic Ras and the tumor suppressor p53 may be even more promising.. We evaluated the effects of S-trans, trans-farnesyl-thiosalicylic acid (FTS), a novel Ras antagonist on human SW480 and HT-29 colon cancer cells, which both harbor a p53 His273 mutation but express activated K-Ras and wild-type, but overexpressed, H-Ras, respectively. Besides cell growth and morphology, levels of cellular Ras proteins, regulation of p53 and p21(waf1/cip1) expression were analyzed by immunoblotting. The cell cycle arresting potential of FTS was quantified by flow cytometry.. We demonstrate that FTS treatment alters the morphology and blocks the growth of SW480 and HT-29 colon cancer cells by both reducing the total amount of Ras and up-regulating the tumor suppressor p53. Furthermore, FTS caused an upregulation of the cyclin-cyclin-dependent kinase (CDK) inhibitor p21(waf1/cip1) and blocked the cell cycle. p53 antisense oligonucleotides not only reduced the level of p53 proteins but correspondingly also blocked the expression of p21(waf1/cip1) in FTS-treated colon cancer cells.. FTS, a unique compound capable of regulating both oncogenic Ras and the tumor suppressor p53 may prove particularly useful for the therapy of colon cancer and other treatment-resistant malignancies where Ras is altered and p53 is either wild-type or mutated in positions that allow residual p53 functions.

Topics: Blotting, Western; Cell Division; Cell Size; Colonic Neoplasms; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinases; Cyclins; Farnesol; Flow Cytometry; Gene Expression Regulation, Neoplastic; Humans; Mutation; Oligonucleotides, Antisense; Oncogene Protein p21(ras); Salicylates; Transfection; Tumor Cells, Cultured; Tumor Suppressor Protein p53; Up-Regulation

Previous research has demonstrated that nonsteroidal anti-inflammatory agents alter the incidence of colorectal cancer. It has been postulated that the response may be due to the effect of these agents on the activities of the cyclooxygenase (COX) enzymes. The COX enzymes catalyze the conversion of arachidonic acid to biologically active prostanoids. Two forms of COX have been identified. COX-1 is a constitutive enzyme, generally involved in cell functions, while COX-2 is commonly an enzyme which is inducible in response to various stimuli, including mitogens. Recently, specific inhibitors of COX-1 and COX-2 enzymes have been developed.. The present study was undertaken to determine the effects of specific COX-1 and COX-2 inhibitors on the proliferation and the induction of apoptosis of intestinal epithelial cells.. A continuously proliferating rat small intestinal cell line (IEC-18) and a mouse colon cancer cell line (WB-2054) were utilized for these experiments. The cells were placed in microwells with serum-free or serum-supplemented media. The effects of serum on proliferation were then evaluated in the presence of the COX-1 inhibitor, valerylsalicyclic acid (VSA), the COX-2 inhibitor, SC-58125, or indomethacin. The presence of COX-1 and COX-2 protein was evaluated by Western blotting. Proliferation of intestinal cells was quantitated by incorporation of [3H]thymidine into DNA and cell counting, and apoptosis was determined by evaluating cell attachment. COX activity was evaluated by prostaglandin E2 production measured by enzyme-linked immunoabsorbent assay (ELISA).. Western blotting of IEC-18 and WB-2054 cell protein demonstrated COX-1 enzyme in cells incubated in serum-free media with increased COX-1 expression produced by incubation in media supplemented with 10% serum. COX-2 enzyme was not demonstrated in serum-free media; however, it was present in cells maintained in 10% serum-supplemented media. Spontaneous DNA synthesis was present in both cell lines and serum increased proliferation. In both cell lines [3H]thymidine incorporation stimulated by serum was inhibited by the COX-2 inhibitor SC-58125, but not by the COX-1 inhibitor VSA. Both indomethacin and SC-58125 produced a dose-dependent increase in apoptotic ratios in both cell lines. PGE2 formation, stimulated by serum, was inhibited by SC-58125, VSA, and indomethacin.. A differential effect on intestinal cell mitogenesis was seen with different COX inhibitors. The COX-2 inhibitor, but not the COX-1 inhibitor, significantly inhibited [3H]thymidine incorporation in both cell types, suggesting COX-2 inhibitors may be specific inhibitors of normal epithelial cell proliferation and growth of malignant cells. SC-58125, a selective inhibitor of COX-2, has a potent apoptosis inducing effect. The inhibition of PGE2 production did not correlate with the inhibition of proliferation, suggesting the two processes are unrelated.

Topics: Animals; Apoptosis; Blood; Blotting, Western; Cell Division; Cell Line; Colonic Neoplasms; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Dinoprostone; DNA; Epithelial Cells; Indomethacin; Intestines; Isoenzymes; Membrane Proteins; Mice; Prostaglandin-Endoperoxide Synthases; Pyrazoles; Rats; Salicylates; Tumor Cells, Cultured

Bile acids are believed to be involved in the formation of colonic cancer, and 5-aminosalicylic acid and other salicylates may have a protective role. The precise mechanisms of both actions are not known, but modifications (stimulation or inhibition) of basal or oxygen-radical induced DNA base hydroxylation as potential early events in tumor formation by these compounds may be involved in such actions. We, therefore, investigated whether: (1) bile acids in concentrations as they occur systemically or intraluminally are able to enhance basal or OH*-radical-stimulated base hydroxylation in DNA from calf thymus; (2) 5-aminosalicylic acid, its main intestinal metabolite N-acetyl-aminosalicylic acid and salicylate, the main aspirin metabolite, are able to inhibit this hydroxylation; and (3) DNA from calf thymus can be used as a model by comparing its base composition and hydroxylation with DNA from normal human colonic mucosa. We found an enhancement of the OH*-radical-induced DNA hydroxylation especially 8-OH adenine with 214.0%. On the other hand 5-ASA, N-acetyl-ASA, and salicylate showed a concentration-dependent inhibition of OH*-stimulated hydroxylation with IC50 between 0.04 +/- 0.01 mM (X +/- SD) and 1.3 +/- 0.1 mM. No effects were observed on basal hydroxylation. Electron spin resonance spectroscopy studies showed reduction of the corresponding base signals pointing to a scavenger mechanism. In DNA isolated from normal human colonic mucosa (N = 7) a similar base distribution was found as in calf thymus; hydroxylation was < or = 1.0% in both systems. From our results we conclude that DNA from calf thymus may serve as a model for human colonic mucosal DNA and that one of the carcinogenic actions of bile acids may be enhancement of oxygen-radical-induced DNA base hydroxylation, especially 8-OH adenine. The absence of effects under unstimulated conditions supports their role as cocarcinogens. The concentration-dependent inhibition of OH*-stimulated DNA hydroxylation by 5-ASA, salicylate, and N-acetyl-ASA may be a possible mechanism of chemoprevention.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Bile Acids and Salts; Cattle; Colonic Neoplasms; DNA; Electron Spin Resonance Spectroscopy; Gas Chromatography-Mass Spectrometry; Gastrointestinal Agents; Humans; Hydroxylation; Inhibitory Concentration 50; Intestinal Mucosa; Salicylates; Thymus Gland

Previous work from our laboratory indicated that the bile salt sodium deoxycholate (NaDOC) induced apoptosis in cultured cells and in normal goblet cells of the colonic mucosa. We also reported that the normal-appearing flat mucosa of patients with colon cancer exhibited apoptosis resistance. Using immunofluorescence in conjunction with confocal microscopy, we now report that high physiological concentrations (0.5 mM) of NaDOC result in the formation of nitrotyrosine residues, a footprint for the formation of reactive nitrogen species, including peroxynitrite, in plasma membrane-associated proteins of HT-29 cells. Because peroxynitrite is formed from the reaction between nitric oxide and superoxide anion, we specifically looked at the role of nitric oxide and superoxide anion in NaDOC-induced apoptosis. Pretreatment of cells with the inhibitor/antioxidants, N-nitro-L-arginine methyl ester, an inhibitor of nitric oxide synthase, copper (II) 3,5-diisopropyl salicylate hydrate, a superoxide dismutase mimetic compound, and Trolox, a water-soluble analog of alpha-tocopherol, alone or in combination, sensitized cells to apoptosis induced by 0.5 mM NaDOC. These results suggest that nitric oxide may be part of a signaling pathway that is responsible for apoptosis resistance. The results also indicate that nitric oxide does not appear to protect cells against NaDOC-induced apoptosis by scavenging superoxide anion.

Topics: Apoptosis; Bile Acids and Salts; Colonic Neoplasms; Deoxycholic Acid; Enzyme Inhibitors; Fluorescent Antibody Technique; Free Radical Scavengers; Humans; Microscopy, Confocal; NG-Nitroarginine Methyl Ester; Nitrates; Nitric Oxide; Nitric Oxide Synthase; Oxidative Stress; Salicylates; Superoxides; Tumor Cells, Cultured; Tyrosine

By using a mRNA differential display technique to search for salicylate suppressible genes, we identified a cDNA in human foreskin fibroblasts, which by GenBankTM DNA data base search shows sequence homology to the recently reported cullin/Cdc53 (CUL) family genes, especially CUL-3. We have cloned the full-length human CUL-3 (Hs-CUL-3) cDNA. It encodes a 768-amino acid polypeptide and has a predicted molecular weight of 88,939. The amino acid sequence of Hs-CUL-3 shows 46% homology to that of its Caenorhabditis elegans ortholog, Ce-CUL-3, and 27 and 23% to that of Hs-CUL-1 and Hs-CUL-2, respectively. Northern blot analysis showed that phorbol 12-myristate 13-acetate increased the expression of Hs-CUL-3 mRNA in a concentration- and time-dependent manner, and this increase was inhibited by sodium salicylate. Hs-CUL-3 widely expressed in human tissues and its expression in cultured COLO205 colon cancer cells was increased when compared with that in normal colon cells. It is likely that Hs-CUL-3 is involved in cell proliferation control.

Topics: Amino Acid Sequence; Animals; Base Sequence; Caenorhabditis elegans; Cell Cycle Proteins; Cells, Cultured; Cloning, Molecular; Colonic Neoplasms; Cullin Proteins; Female; Fibroblasts; Gene Expression Regulation; Humans; Male; Molecular Sequence Data; Multigene Family; Organ Specificity; Pregnancy; Recombinant Proteins; RNA, Messenger; Salicylates; Salicylic Acid; Sequence Alignment; Sequence Homology, Amino Acid; Skin; Tetradecanoylphorbol Acetate; Transcription, Genetic; Tumor Cells, Cultured

The transport of monocarboxylic acid drugs such as salicylic acid was examined in the human colon adenocarcinoma cell line, Caco-2 cells that possess intestinal epithelia-like properties. [14C]Salicylic acid transport was pH-dependent and appeared to follow the pH-partition hypothesis. However, 10 mM unlabelled salicylic acid significantly reduced the permeability coefficient of [14C]salicylic acid. Kinetic analysis of the concentration dependence of the permeation rate of salicylic acid across Caco-2 cells showed both saturable (Kt = 5.28 +/- 0.72 mM Jmax = 36.6 +/- 3.54 nmol min-1 (mg protein)-1) and nonsaturable (kd = 0.37 +/- 0.08 microL min-1 (mg protein)-1) processes. The permeation rate of [14C]salicylic acid was competitively inhibited by both acetic acid and benzoic acid, which were demonstrated in our previous studies to be transported in the carrier-mediated-transport mechanism which is responsible for monocarboxylic acids. Furthermore, certain monocarboxylic acids significantly inhibited [14C]salicylic acid transport, whereas salicylamide and dicarboxylic acids such as succinic acid did not. From these results, it was concluded that the transcellular transport of [14C]salicylic acid across Caco-2 cells is by the pH-dependent and carrier-mediated transport mechanism specific for monocarboxylic acids.

Topics: Acetates; Acetic Acid; Adenocarcinoma; Anti-Arrhythmia Agents; Benzoates; Benzoic Acid; Biological Transport, Active; Cell Membrane Permeability; Colonic Neoplasms; Dose-Response Relationship, Drug; Humans; Hydrogen-Ion Concentration; Intestinal Absorption; Linear Models; Salicylates; Salicylic Acid; Temperature; Tumor Cells, Cultured

Aetiology of ulcerative colitis and Crohn's disease is unknown. Therefore causal therapy is not possible. Conservative treatment for both diseases is of antiinflammatory, symptomatic and substituting nature. Surgical intervention is indicated if conservative treatment fails or if dangerous complications occur. The right moment for an operation can only be determined in close cooperation between internist and surgeon.

Topics: Adrenocorticotropic Hormone; Anemia; Anti-Inflammatory Agents; Blood Transfusion; Colitis, Ulcerative; Colonic Neoplasms; Crohn Disease; Dietary Proteins; Drug Combinations; Humans; Lactose Intolerance; Parenteral Nutrition; Psychotherapy; Salicylates; Sulfonamides; Vitamins

Topics: Animals; Antigens, Neoplasm; Carcinoembryonic Antigen; Chromatography; Colonic Neoplasms; Electrophoresis; Humans; Immunodiffusion; Iodine Isotopes; Methods; Microchemistry; Neoplasm Metastasis; Rabbits; Radioimmunoassay; Salicylates