RESUMO
OBJECTIVES: In a previous cross-sectional study, the authors found a higher rate of TP53 mutation in oral lichen planus (OLP) than in hyperkeratosis. By analysing for TP53 mutations in serial samples from patients on long-term follow-up of their oral lesions, it was hoped to determine if these mutations were related to disease progression. METHODS: Eight patients presenting with lesions diagnosed clinically as oral leukoplakia or lichen planus were followed from 2 to 12 years. Two to five samples of archival biopsy tissue were analysed from each patient by constant denaturant gradient gel electrophoresis for hotspots A, B, C, D and exon 6. RESULTS: Four patients were diagnosed clinically as OLP: two of these were confirmed histopathologically, one was diagnosed as non-specific hyperkeratosis and one as cancer. Four patients had leukoplakia only, with a histopathological diagnosis of hyperkeratosis. Seven patients had TP53 mutations, three of them on repeated occasions. All five patients who developed squamous-cell carcinoma had mutations. Two of them had mutated pre-malignant lesions, and one of these previously had a non-mutated cancer. Three patients had two different primary cancers, only one of them mutated. One patient developed a mutated cancer 5 years after the last mutation-free biopsy. Of the cancer-free patients, a lesion regarded clinically as cancer-suspicious in one case was mutated, in another patient two OLP lesions were mutated, the third had five biopsies taken during 8 years, all non-mutated. CONCLUSIONS: TP53 mutations may occur early or late in the development of oral squamous-cell carcinoma.
Assuntos
Carcinoma de Células Escamosas/genética , Leucoplasia Oral/genética , Líquen Plano Bucal/genética , Neoplasias Bucais/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica/genética , Análise Mutacional de DNA , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica , Genes p53 , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas/genética , Estudos RetrospectivosRESUMO
AIMS: Nicotine replacement therapy (NRT) is an established aid in stopping smoking, while the role of antidepressants remains uncertain. Antidepressants added to NRT might improve abstinence rates. Our aim was to determine the efficacy of nicotine inhaler and fluoxetine vs. nicotine inhaler and placebo in attempts to quit smoking. DESIGN: A randomized, double-blind, placebo-controlled trial. SETTING: A smoker's cessation clinic. PARTICIPANTS: One hundred volunteers smoking 10 cigarettes/day or more. INTERVENTIONS: Subjects were instructed to start taking a daily dose of 10 mg of fluoxetine or placebo 16 days before stopping smoking, then 20 mg 10 days before quitting, continuing for up to at least 3 months. Subjects were instructed to use 6-12 units per day of nicotine inhalers after stopping smoking for up to 6 months. MEASUREMENTS: Continuous abstinence rates recorded at various time points up to 12 months from the quit date. FINDINGS: The sustained abstinence rate for the inhaler-fluoxetine group was 54%, 40%, 29% and 21% after 1.5, 3, 6 and 12 months, respectively, compared to 48%, 40%, 32% and 23% for the inhaler-placebo group. The differences were not significant at any time point. Abstinence up to 3 months was more likely in older smokers, those with a lower Beck Depression Inventory Score (BDI), lower Fagerström Test of Nicotine Dependence (FTND) score and no history of alcoholism. Fluoxetine appeared to increase abstinence rates among high BDI smokers compared to high BDI smokers assigned placebo. Serum levels of nicotine during treatment in the inhaler-fluoxetine group were lower than in the inhaler-placebo group so that fluoxetine may have reduced inhaler use through a common site of action. CONCLUSIONS: We found no evidence that fluoxetine treatment when used as an adjunct to NRT in unselected smokers is effective, but there may be an advantage to using it in depressed smokers.