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Western Blot Results (western + blot_result)
Selected AbstractsEnhanced sensitivity to DNA damage induced by cooking oil fumes in human OGG1 deficient cellsENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 4 2008Mei Wu Abstract Cooking oil fumes (COFs) have been implicated as an important nonsmoking risk factor of lung cancer in Chinese women. However, the molecular mechanism of COFs-induced carcinogenicity remains unknown. To understand the molecular basis underlying COFs-induced cytotoxicity and genotoxicity as well as the roles of hOGG1 in the repair of COFs-induced DNA damage, a human lung cancer cell line with hOGG1 deficiency, A549-R was established by using a ribozyme gene targeting technique that specifically knockdowned hOGG1 in A549 lung adenocarcinoma cells. MTT and comet assays were employed to examine cell viability and DNA damage/repair, respectively, in A549-R and A549 cell lines treated with COF condensate (COFC). RT-PCR and Western blot results showed that the expression of hOGG1 in A549-R cell line was significantly decreased compared with that in A549 cell line. The concentration of COFC that inhibited cell growth by 50% (the IC50) in the A549-R cell line was much lower than that in the A549 cell line, and more COFC-induced DNA damage was detected in the A549-R cell line. The time course study of DNA repair demonstrated delayed repair kinetics in the A549-R cell line, suggesting a decreased cellular damage repair capacity. Our results showed that hOGG1 deficiency enhanced cellular sensitivity to DNA damage caused by COFC. The results further indicate that hOGG1 plays an important role in repairing COF-induced DNA damage. Our study suggests that COFs may lead to DNA damage that is subjected to hOGG1 -mediated repair pathways, and oxidative DNA damage may be involved in COF-induced carcinogenesis. Environ. Mol. Mutagen., 2008. © 2008 Wiley-Liss, Inc. [source] Methotrexate induction of human sulfotransferases in Hep G2 and Caco-2 cellsJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2005Xinrong Chen Abstract Methotrexate (MTX) was the first antifolate drug developed for the treatment of cancer. It is also effective in treating inflammatory and autoimmune diseases. Sulfotransferases are phase II drug-metabolizing enzymes and their induction by hormones and endogenous molecules is relatively well known, although xenobiotic drug induction of sulfotransferases has not been well studied. In the present investigation, MTX is shown to be a xenobiotic inducer of human sulfotransferases in transformed human liver (Hep G2) and intestinal (Caco-2) cells. Following MTX treatment, various sulfotransferases were induced in both cell lines. Enzyme assay, Western blot and reverse-transcription polymerase chain reaction (RT-PCR) results demonstrated that protein and mRNA expressions of human simple phenol sulfotransferase (P-PST), human monoamine sulfotransferase (M-PST), human dehydroepiandrosterone sulfotransferase (DHEA-ST) and human estrogen sulfotransferase (EST) were induced in Hep G2 cells; M-PST and DHEA-ST were induced in Caco-2 cells. Inductions in both cell lines were dose dependent. Enzyme activity and Western blot results were in good agreement with RT-PCR results, suggesting that the induction is at the gene transcription level. Folic acid had a significantly lesser effect on sulfotransferases compared with MTX. Interestingly, the induction of different sulfotransferases by MTX was inhibited by high doses of folic acid at both protein and mRNA levels in Hep G2 cells. Methotrexate is the first antifolate and apoptosis-inducing drug to show induction of sulfotransferases in Hep G2 cells and Caco-2 cells. The inhibition by folic acid suggests a possible mechanism for MTX induction. Copyright © 2005 John Wiley & Sons, Ltd. [source] Biochanin A induction of sulfotransferases in ratsJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 2 2010Yue Chen Abstract Biochanin A (BCA) is a dietary isoflavone present in red clover (Trifoliumn pretense) and many herbal products. BCA has been reported to have chemopreventive actions against various cancers including prostate, breast, colon cancer, and so on. Sulfotransferases are a family of phase II drug-metabolizing enzymes, which are important for xenobiotic detoxification and regulation of biological signaling molecule biological activities. Sulfotransferase gene expressions are regulated by different hormones and xenobiotics. Improper regulation of sulfotransferases leads to improper functions of biological signaling molecules, which in turn can cause cancer or other diseases. BCA inhibits the enzyme activities of the phase I drug-metabolizing enzymes CYP1A1 and CYP1B1 in Chinese hamster ovary cells and induces the phase II drug-metabolizing enzymes UDP-glucuronosyltransferases in human prostate cancer cells. BCA induction of sulfotransferases has not been studied. This investigation evaluates the in vivo regulation of sulfotransferases at protein and mRNA levels in the liver and intestine of Sprague-Dawley rats treated with BCA (0, 2, 10, and 50 mg/kg/day) for 7 days. Our experimental results demonstrate for the first time that chronic BCA treatment can significantly induce the expression of rat sulfotransferase 1A1 (rSULT1A1, AST-IV), sulfotransferase 2A1 (rSULT2A1, STa), and rat estrogen sulfotransferase (rSULT1E1, EST) in rat liver and intestine. Our Western blot results are in good agreement with real-time RT-PCR data, suggesting that BCA induction of sulfotransferases occurs at the transcriptional level. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 24:102,114, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20318 [source] Differential expression of p63 isoforms in normal skin and hyperproliferative conditionsJOURNAL OF CUTANEOUS PATHOLOGY, Issue 8 2009So-Young Kim Background:, The p63 is regarded as a potential stem cell marker. Methods:, Expression of p63 isoforms was examined in normal skin and hyperproliferative conditions including psoriasis and artificial skin equivalents (SEs). Rapidly adhering (RA) and slowly adhering (SA) cells were isolated, and Western blotting was performed. Results:, Expression of p63 (4A4) and p63 (H-137) is similar in all conditions, although there is some variation in psoriasis. However, expression of p63, (C-12) is markedly different. In normal skin, p63, (C-12)-positive cells were scattered in whole epidermis. But in psoriasis, p63, (C-12)-positive cells were observed at the tips of rete ridges. In SEs, p63, (C-12)-positive cells were not well observed. Western blot results showed that the RA cells express p63 (4A4) and p63 (H-137) strongly compared with SA or nonadhering (NA) cells. In contrast, SA or NA cells strongly express p63, (C-12). Conclusions:, Results suggest that both p63 (4A4) and p63 (H-137) can detect epidermal stem cells. But, p63 (H-137) seemed to be a better marker because p63 (H-137)-positive cells were more localized at basal layer. In addition, it can be said that p63, (C-12) can detect TAp63, which is important in differentiation of epidermis. Furthermore, it is concluded that molecular control of TAp63 is especially disorganized in hyperproliferative condition including psoriasis and SEs. [source] | ||||||||||