RESUMO
Breast cancer is the most common cancer among women worldwide. Genetic alterations prevalent in breast cancer are still being elucidated. In this report, changes in 30 breast cancer tissues, in comparison with normal tissues from Thai patients, were analyzed by arbitrarily primed polymerase chain reaction (AP-PCR). Genetic instability was detected by DNA fingerprinting obtained with 13 of 60 random primers. Of these, at least one amplification band, the incidence ranging from 27 to 80%, was observed in DNA amplified with 8 primers, whereas a band loss was exhibited with from 6 primers, the incidences ranging from 23 to 40%. Likewise, an amplification band amplified from primer D15 was observed in 80% of this patient group and a band loss produced from primer B12 presented in 40% of all cases. These results showed that AP-PCR is effective for the detection of genetic alterations in breast cancer tissues.
Assuntos
Neoplasias da Mama/genética , DNA de Neoplasias/genética , Predisposição Genética para Doença , Reação em Cadeia da Polimerase/métodos , Neoplasias da Mama/epidemiologia , Impressões Digitais de DNA , Feminino , Amplificação de Genes , Deleção de Genes , Marcadores Genéticos , Humanos , Pessoa de Meia-Idade , Mutação/genética , Fenótipo , Tailândia/epidemiologiaRESUMO
H-, K- and N-ras gene mutations were analyzed in lung cancer from Thai patients. Thirteen out of 58 cases (22%) harbored the mutations. Ten cases showed K-ras gene mutations at codon 12, 1 case presented a mutation at codon 13 and another case exhibited a mutation at codon 63. Silent mutations of N-ras gene in codons 57 and 62 were seen in one patient, whilst no H-ras mutation was found in these patients. Bases change in K-ras gene were G right curved arrow T transversion (62%), G right curved arrow A transition (15%) and G right curved arrow C transition (15%), whereas T right curved arrow G transversion and A right curved arrow G transition were detected in N-ras mutant gene.
Assuntos
Análise Mutacional de DNA , Genes ras , Neoplasias Pulmonares/genética , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Códon , DNA/química , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fumar , TailândiaRESUMO
This study was performed to detect amplification of DNA sequences on chromosomes 4p15.2 and 6q23-24, obtained from formalin-fixed, paraffin-embedded, breast-cancer tissues. The prognostic relevance of the amplification was also demonstrated. DNA from formalin-fixed, paraffin-embedded tumor and corresponding normal tissues of 53 patients with breast cancer was extracted and amplified by real-time quantitative PCR technique. Amplification of the DNA sequences on chromosomes 4p15.2 and 6q23-24 was detected in 23 (43%) and 32 (60%) cases, respectively. Thirty-six (68%) cases showed amplification on both or one of the chromosomes. These frequencies are similar to that obtained from fresh samples in our previous study. In addition, amplification of the DNA on chromosomes 4p15.2 and / or 6q23-24 was predominantly observed in tumors with invasive ductal carcinoma. The findings in this study demonstrate that DNA extracted from formalin-fixed, paraffin-embedded breast tumors can be used to determine amplification of DNA sequences on selective chromosomal regions. We also suggest that the amplified DNA on chromosomal regions 4p15.2 and 6q23-24 might be involved in the development and progression of breast cancer.