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The transcription of the ΔN133p53 isoform of the TP53 gene is controlled by an internal promoter region (IPR) containing eight polymorphisms in 11 common haplotypes, following a resequencing of 47 Caucasians. We assayed the functional effects of the commonest six haplotypes on the promoter activity with a luciferase reporter system, in HeLa and 293T cells. These studies showed that different IPR haplotypes are associated with differences in the promoter activity resulting in marked variation in the baseline expression of ΔN133p53. In vivo quantitative-polymerase chain reaction (PCR) on human tissues confirmed that the baseline levels of ΔN133p53 showed haplotype specific differences that paralleled those seen in vitro. When cell lines were treated with camptothecin, the fold-increase in ΔN133p53 levels was dose-dependent but haplotype-independent (i.e., similar for all the haplotypes). Finally, we used an electrophoretic mobility shift assay to analyze the rs1794287 polymorphism and found changes in the pattern of protein binding. This partially confirmed our in silico analysis showing that the polymorphism rs1794287 can affect the function of the internal promoter by changing its affinity for several transcription factors. Thus, we showed that the expression of ΔN133p53 is under genetic control, and suggested the presence of interindividual differences underlying this mechanism. Hum Mutat 31:1–10, 2010. © 2010 Wiley-Liss, Inc.

The role of genes coding for xenobiotic metabolizing enzymes (XMEs) and the risk of lung cancer is unclear. Under the assumption that these genes may be more important among people having a diagnosis of lung cancer at younger ages, we have investigated the role of single-nucleotide polymorphisms (SNPs) within phase I and phase II XME genes, and also genes involved in the metabolism of nucleic acids in a series of young onset patients and matched controls. We genotyped 299 lung cancer cases diagnosed before the age of 50 and 317 controls, from six countries of Central and Eastern Europe, by use of an oligonucleotide microarray and arrayed primer extension technique for 45 SNPs in 15 phase I XME genes, 46 SNPs in 17 phase II genes and 9 SNPs in 4 genes related to metabolism of nucleic acids. Heterozygote carriers of SNPs in CYP1A2 1545T>C, -164C>A and -740T>G; CYP2A6 -47A>C; MDR1 3435T>C; NAT1 1088T>A and 1095A>C; GSTA2 S112T; GSTM3 V224I and MTHFR A222V had altered risk of developing lung cancer. Phenotypes reconstructed after haplotype analyses showed that the carriers of the combined NAT1 fast+ NAT2 fast phenotypes were at lower risk when compared with those with the combined NAT1 slow + NAT2 slow acetylator phenotypes. Finally, extensive EPHX1 metabolizers showed an increased risk as compared with the poor metabolizers. © The Author 2007. Published by Oxford University Press. All rights reserved.

An oligonucleotide microarray based on the arrayed-primer extension (APEX) technique has been developed to simultaneously identify pathogenic fungi frequently isolated from invasive and superficial infections. Species-specific oligonucleotide probes complementary to the internal transcribed spacer 1 and 2 (ITS1 and ITS2) region were designed for 24 species belonging to 10 genera, including Candida species ( Candida albicans , Candida dubliniensis , Candida famata , Candida glabrata , Candida tropicalis , Candida kefyr , Candida krusei , Candida guilliermondii , Candida lusitaniae , Candida metapsilosis , Candida orthopsilosis , Candida parapsilosis , and Candida pulcherrima ), Cryptococcus neoformans , Aspergillus species ( Aspergillus fumigatus and Aspergillus terreus ), Trichophyton species ( Trichophyton rubrum and Trichophyton tonsurans ), Trichosporon cutaneum , Epidermophyton floccosum , Fusarium solani , Microsporum canis , Penicillium marneffei , and Saccharomyces cerevisiae . The microarray was tested for its specificity with a panel of reference and blinded clinical isolates. The APEX technique was proven to be highly discriminative, leading to unequivocal identification of each species, including the highly related ones C. parapsilosis , C. orthopsilosis , and C. metapsilosis . Because of the satisfactory basic performance traits obtained, such as reproducibility, specificity, and unambiguous interpretation of the results, this new system represents a reliable method of potential use in clinical laboratories for parallel one-shot detection and identification of the most common pathogenic fungi.