Chromosome-specific induction of micronuclei and chromosomal aberrations by mitomycin C: Involvement of human chromosomes 9, 1 and 16.
Mutat Res Genet Toxicol Environ Mutagen
; 896: 503753, 2024.
Article
em En
| MEDLINE
| ID: mdl-38821666
ABSTRACT
Cytogenetic studies have shown that human chromosomes 1, 9, and 16, with a large heterochromatic region of highly methylated classical satellite DNA, are prone to induction of chromatid breaks and interchanges by mitomycin C (MMC). A couple of studies have indicated that material from chromosome 9, and possibly also from chromosomes 1 and 16, are preferentially micronucleated by MMC. Here, we further examined the chromosome-specific induction of micronuclei (MN; with and without cytochalasin B) and chromosomal aberrations (CAs) by MMC. Cultures of isolated human lymphocytes from two male donors were treated (at 48â¯h of culture, for 24â¯h) with MMC (500â¯ng/ml), and the induced MN were examined by a pancentromeric DNA probe and paint probe for chromosome 9, and by paint probes for chromosomes 1 and 16. MMC increased the total frequency of MN by 6-8-fold but the frequency of chromosome 9 -positive (9+) MN by 29-30-fold and the frequency of chromosome 1 -positive (1+) MN and chromosome 16 -positive (16+) MN by 12-16-fold and 10-17-fold, respectively. After treatment with MMC, 34-47 % of all MN were 9+, 17-20 % 1+, and 3-4 % 16+. The majority (94-96 %) of the 9+ MN contained no centromere and thus harboured acentric fragments. When MMC-induced CAs aberrations were characterized by using the pancentromeric DNA probe and probes for the classical satellite region and long- and short- arm telomeres of chromosome 9, a high proportion of chromosomal breaks (31 %) and interchanges (41 %) concerned chromosome 9. In 83 % of cases, the breakpoint in chromosome 9 was just below the region (9cen-q12) labelled by the classical satellite probe. Our results indicate that MMC specifically induces MN harbouring fragments of chromosome 9, 1, and 16. CAs of chromosome 9 are highly overrepresented in metaphases of MMC-treated lymphocytes. The preferential breakpoint is below the region 9q12.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cromossomos Humanos Par 1
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Cromossomos Humanos Par 9
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Cromossomos Humanos Par 16
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Aberrações Cromossômicas
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Mitomicina
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Micronúcleos com Defeito Cromossômico
Limite:
Adult
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Humans
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Male
Idioma:
En
Revista:
Mutat Res Genet Toxicol Environ Mutagen
Ano de publicação:
2024
Tipo de documento:
Article
País de publicação:
Holanda