RESUMO
Chromosome instability is associated with an increased risk of malignancy. However, the quantitative analysis of chromosome breaks provided by the bleomycin test requires additional analysis aimed for the localisation of chromosome aberrations. For this reason, the metaphasis slides prepared for bleomycin test were stained with fluorochrome DAPI to estimate chromosome breaks in particular chromosomes. The additional staining of chromosomes can be recognised as an extension of the classical bleomycin test addressed for identification of structural aberrations. Preliminary results indicate that the most frequent chromosome breaks were found in chromosomes 1, 2, 3, 7 and 13.
Assuntos
Bleomicina , Aberrações Cromossômicas/diagnóstico , Cromossomos Humanos 1-3 , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 7 , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/genética , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Marcadores Genéticos , Humanos , Neoplasias Laríngeas/sangue , Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-IdadeRESUMO
The aim of the article is a review of own cytogenic studies on laryngeal cancer confronted with the literature data. Spontaneous and bleomycin-induced chromosome instability was analysed in peripheral blood lymphocytes in relation to genetic risk of cancer incidence and progression. Comparative genome hybridization (CGH) was applied to demonstrate gains and losses of DNA copy number in tumour and non-tumour laryngeal mucosa. The profiles of imbalances of DNA copy number were shown to differ between metastazing and non-metastazing tumours. Preliminary data indicate a frequent loss of Y chromosome in tumour cells. The loss of heterozygosity at chromosome p53 locus (17p) has been shown to be more frequent than at chromosome locus coding 16 gene (9p). Altogether, the experiments have proven that a dynamics of chromosome aberrations is highest at the stage of metastasis.