Although deletions of cell cycle regulatory gene loci have long been reported in various malignancies, little is known regarding their relevance in pediatric T-cell lymphoblastic lymphoma (T-LBL) and T-cell lymphoblastic leukemia (TALL). The current study focused on loss of heterozygosity (LOH) analyses of the CDKN2A/B (chromosome 9p), ATM (chromosome 11q) and p53 (chromosome 17p) gene loci. Fr...

BACKGROUND Microsatellite instability (MI) and loss of heterozygosity (LOH) are described in lung cancer specimens. However, their importance in tumorigenesis remains unknown. The aim of this study was to identify the presence of MI and LOH in human tumor and normal bronchial mucosa DNA. METHODS We performed biopsies with fiberoptic bronchoscopy and took specimens from the tumor and from the ...

BACKGROUND Although loss of heterozygosity (LOH) at chromosome location 18q21 and decreased expression of SMAD4 in invasive colorectal cancers (CRCs) correlate with poor patient survival, the prognostic value of LOH at 18q21 and sub-cellular localization of SMAD4 have not been evaluated in relation to tumor stage. METHODS Genomic DNA samples from 209 formalin-fixed, paraffin-embedded sporadic...

We analyzed allelic loss at the p53 gene (17p13) and at chromosome region 9p21 in 35 primary head and neck squamous cell carcinomas. Loss of heterozygosity (LOH) at p53 and 9p21 was found in 50 and 75% of informative cases, respectively. LOH at the p53 gene did not increase significantly with tumor stage, but was more frequent in moderately and poorly differentiated tumors than in well-differen...

The loss of chromosomes 1p-19q is the only prognostic molecular alteration identified in low-grade gliomas (LGGs) to date. Search for loss of heterozygosity (LOH) on chromosomes 1p, 9p, 10q, and 19q was performed in a series of 231 LGGs. Loss of chromosomes 1p-19q was strongly correlated with prolonged progression-free survival (PFS) and overall survival (OS) in univariate and multivariate anal...

BACKGROUND Loss of heterozygosity (LOH) of selected regions at chromosomes 3p and 17p in non-small cell lung cancer (NSCLC) and the association of these abnormalities with major clinical parameters and prognosis were studied. MATERIALS AND METHODS The study group included 92 consecutive primary NSCLC tumours and four microsatellite markers from chromosome 3p and three markers from 17p were an...

MOTIVATION Oligonucleotide microarrays allow genotyping of thousands of single-nucleotide polymorphisms (SNPs) in parallel. Recently, this technology has been applied to loss-of-heterozygosity (LOH) analysis of paired normal and tumor samples. However, methods and software for analyzing such data are not fully developed. RESULT Here, we report automated methods for pooling SNP array replicate...

We have analyzed DNA from 46 neuroblastoma tumors of all clinical stages and five ganglioneuroma tumors together with corresponding control DNA for loss of heterozygosity (LOH) on the distal 1p chromosomal region (1p-LOH). The markers used for the analyses were genetically mapped DNA polymorphisms detectable with PCR analysis. In general, there was concordance among aggressive tumor stage, 1p d...