1.Joint effect among p53, CYP1A1, GSTM1 polymorphism combinations and smoking on prostate cancer risk: an exploratory genotype-environment interaction study.
Luis A QUIÑONES ; Carlos E IRARRÁZABAL ; Claudio R ROJAS ; Cristian E ORELLANA ; Cristian ACEVEDO ; Christian HUIDOBRO ; Nelson E VARELA ; Dante D CÁCERES
Asian Journal of Andrology 2006;8(3):349-355
AIMTo assess the role of several genetic factors in combination with an environmental factor as modulators of prostate cancer risk. We focus on allele variants of low-penetrance genes associated with cell control, the detoxification processes and smoking.
METHODSIn a case-control study we compared people carrying p53cd72 Pro allele, CYP1A1 M1 allele and GSTM1 null genotypes with their prostate cancer risk.
RESULTSThe joint risk for smokers carrying Pro* and M1*, Pro* and GSTM1null or GSTM1 null and CYP1A1 M1* variants was significantly higher (odds ratio [OR]: 13.13, 95% confidence interval [CI]: 2.41-71.36; OR: 3.97, 95% CI: 1.13-13.95 and OR: 6.87, 95% CI: 1.68-27.97, respectively) compared with that for the reference group, and for non-smokers was not significant. OR for combinations among p53cd72, GSTM1 and CYP1A1 M1 in smokers were positively and significantly associated with prostate cancer risk compared with non-smokers and compared with the putative lowest risk group (OR: 8.87, 95% CI: 1.25-62.71).
CONCLUSIONOur results suggest that a combination of p53cd72, CYP1A1, GSTM1 alleles and smoking plays a significant role in modified prostate cancer risk on the study population, which means that smokers carrying susceptible genotypes might have a significantly higher risk than those carrying non-susceptible genotypes.
Aged ; Confidence Intervals ; Cytochrome P-450 CYP1A1 ; genetics ; Gene Amplification ; Genes, p53 ; Genetic Variation ; Genotype ; Glutathione Transferase ; genetics ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Prostatic Neoplasms ; epidemiology ; genetics ; Risk Factors ; Smoking
2.Glutathione peroxidase activity in cell cultures from different regions of human epididymis.
Enrique CASTELLÓN ; Hernán RIOSECO ; Juan ROJAS ; Michel ROYER ; Eduardo SALAS ; Héctor CONTRERAS ; Christian HUIDOBRO
Asian Journal of Andrology 2005;7(1):33-37
AIMTo study the secretory activity and androgen regulation of glutathione peroxidase (GPx) in epithelial cell cultures from human epididymis.
METHODSTissue was obtained from patients undergoing therapeutic orchidectomy for prostatic cancer. Epithelial cell cultures were obtained from the caput, corpus and cauda epididymides. Enzymatic activity was measured in conditioned media by colorimetric methods in absence or presence of 1, 10 or 100 nmol/L testosterone. The effect of 1 micromol/L flutamide was also evaluated.
RESULTSGPx activity was higher in cultures from corpus and cauda than caput epididymidis. The presence of different concentrations of testosterone increase enzyme activity in cell cultures from all epididymal regions. Addition of flutamide reverses the androgen dependent increase of GPx activity.
CONCLUSIONGPx activity is secreted from human epididymal cells in a region dependent manner and is regulated by androgens.
Aged ; Androgen Antagonists ; pharmacology ; Cell Culture Techniques ; Epididymis ; enzymology ; Flutamide ; pharmacology ; Glutathione Peroxidase ; drug effects ; metabolism ; Humans ; Male ; Middle Aged ; Testosterone ; metabolism