ABSTRACT
DNA hypermethylation of CpG-rich promoter sequences is associated with tumor suppressor gene inactivation in many human cancers, notably in carcinoma of the prostate and the urinary bladder. Recently, the mouse homologue of the tumor necrosis factor receptor superfamily 6 (TNFRSF6) gene was reported to be inactivated by DNA methylation in various cell types. The Fas (CD95, Apo-1) protein encoded by the TNFRSF6 gene is an important mediator of apoptosis, which also is downregulated in different types of human carcinoma. We therefore investigated the methylation of the TNFRSF6 promoter in prostatic and bladder carcinomas and cell lines. In a restriction enzyme polymerase chain reaction assay, four of 32 prostatic carcinomas and three of 15 advanced bladder carcinomas showed evidence of hypermethylation at the rel/nuclear factor kappaB (NFkappaB) binding sites essential for promoter activity. The DU145 cell line derived from a metastasis of a prostate carcinoma also displayed hypermethylation in this assay, which was confirmed by bisulfite sequencing. Treatment of DU145 cells with the methylation inhibitor deoxyazacytidine slightly increased Fas protein expression, as detected by flow cytometry analysis. In vitro methylation of the TNFRSF6 promoter at the rel/NFkappaB sites completely abolished its activity. Thus, although the TNFRSF6 gene can be inactivated efficiently by DNA methylation, hypermethylation occurs neither frequently nor extensively in human carcinomas and appears to play a limited role in downregulation of Fas expression.
Subject(s)
Azacitidine/analogs & derivatives , DNA Methylation , NF-kappa B/genetics , Oncogene Proteins v-rel/genetics , Prostatic Neoplasms/genetics , Receptors, Tumor Necrosis Factor/genetics , Thiolester Hydrolases/genetics , fas Receptor/genetics , Aged , Antimetabolites, Antineoplastic/pharmacology , Azacitidine/pharmacology , DNA Mutational Analysis , DNA Primers/chemistry , DNA, Neoplasm/analysis , Decitabine , Flow Cytometry , Gene Expression , Humans , Immunoenzyme Techniques , In Vitro Techniques , Male , Middle Aged , Promoter Regions, Genetic , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , RNA, Messenger/analysis , RNA, Messenger/metabolism , Receptors, Tumor Necrosis Factor/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Thiolester Hydrolases/metabolism , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/metabolism , fas Receptor/metabolismABSTRACT
Preliminary evidence suggests that genetic polymorphisms in certain enzymes involved in xenobiotic metabolism and chemical defense could modify a susceptibility to prostate cancer. In the present study, two recently described phenol sulphotransferase SULT1A1 alleles (SULT1A1*1, SULT1A1*2) were investigated using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach. Genotyping was performed on DNA isolated from white blood cells from 134 patients with prostate cancer and 184 healthy control subjects. Both the prostate cancer patients and the controls demonstrated similar frequencies of the variant allele SULT1A1*2 (35.1% vs 39.1%). Homozygosity for the variant allele was slightly less frequent in cancer patients than controls (12.7% vs 17.4%). Our study does not support the hypothesis that the phenol sulphotransferase variant allele SULT1A1*2 with a G/A transition at nucleotide 638 is a risk modifier for prostate cancer in the Caucasian population.
Subject(s)
Arylsulfotransferase , Polymorphism, Genetic , Prostatic Neoplasms/enzymology , Prostatic Neoplasms/genetics , Sulfotransferases/genetics , Alleles , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Polymerase Chain Reaction , Polymorphism, Restriction Fragment LengthABSTRACT
BACKGROUND: The aim of this study was to determine which motility data of patients with noncardiac chest pain (NCCP) differ from those of controls on the basis of long-term manometry and to evaluate the coexistence of motility disorders and pathologic acid reflux. Further, motility disorders were tested as to whether they were secondary to acid reflux. METHODS: Combined long-term pH/manometry was performed in 95 patients with NCCP, using one pH-electrode and two pressure transducers. The motility data were compared with those of healthy controls (n = 40). In addition, an intraindividual patient-oriented motility analysis was performed. Evaluated were the amplitude, the duration in the distal and proximal esophagus, and the type of propagation, propulsive and simultaneous, of esophageal contractions. Ten patients with pathologic acid reflux and hypermotility disorders received 20 mg omeprazole twice daily and were investigated again 4 weeks after therapy began. RESULTS: The median distal pressure amplitude (39.4 versus 28.9 mmHg, p < 0.0001) and the median percentage of simultaneous contractions (18.5% versus 10%; p < 0.0001) were significantly higher in patients with NCCP than in controls. In addition, patients whose symptoms correlated with abnormal motility (n = 18) had a significantly higher median duration of contractions (3.8 sec versus 3.2 sec; p < 0.03) than controls Patients with pathologic acid reflux showed a higher median distal pressure amplitude (38.3 mmHg versus 28.9 mmHg; p < 0.0001) and median percentage of simultaneous contractions (18% versus 10%; p < 0.0001) than controls. Furthermore, a high rate of coexistence with hypermotility disorders was observed (64%). These disorders persisted after acid suppression therapy. CONCLUSIONS: Patients with NCCP differ from controls in their esophageal motility. Simultaneous contractions of increased amplitude and duration are pathologic. The intraindividual patient-oriented motility analysis is an appropriate evaluation method. Hypermotility disorders occur often in patients with pathologic acid reflux, but apparently they are not dependent on it.
