RESUMO
BACKGROUND: Nasopharyngeal cancer (NPC) is multifactorial, and the genetic background may be a crucial etiologic factor. Transforming growth factor-beta1 (TGF-beta1) is a multifunctional cytokine, it promotes tumor growth and metastasis in later stages of phase of cancer development. Variations in the DNA sequence in the TGF-beta1 gene may lead to altered TGF-beta1 production and/or activity, and so this can modulate an individual's susceptibility to NPC. To test this hypothesis, we investigated the association of the TGF-beta1 polymorphisms and their haplotypes with the risk of NPC in a Chinese population. METHODS: We analyzed 2 single nucleotide polymorphisms (SNPs) of TGF-beta1 gene promoter -509C/T and 869T/C (Leu10Pro) at exon one in 108 patients with NPC and 120 age- and sex-matched controls in a Chinese population, using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy. RESULTS: There were significant differences in the genotype and allele distribution of -509C/T and 869T/C (Leu10Pro) polymorphisms of the TGF-beta1 gene among cases and controls. The -509T and 869C alleles carriers were associated with a significantly increased risk of NPC as compared with the non-carriers (OR=1.64, 95% CI, 1.13-2.39, P=0.009 and OR=1.70, 95% CI, 1.17-2.46, P=0.006, respectively). Consistent with the results of the genotyping analyses, the -509T/869C haplotype was associated with a significantly increased risk of NPC as compared with the -509C/869T haplotype (OR=1.68; 95% CI, 1.14-2.48; P=0.009). CONCLUSION: TGF-beta1 -509C/T and 869T/C polymorphisms, and their haplotypes are significantly associated with the risk of NPC. Our data suggests that TGF-beta1 -509C/T and 869T/C polymorphisms could be used as genetic susceptibility markers of the NPC.
Assuntos
Carcinoma de Células Escamosas/genética , Predisposição Genética para Doença , Haplótipos/genética , Neoplasias Nasofaríngeas/genética , Polimorfismo de Nucleotídeo Único/genética , Fator de Crescimento Transformador beta1/genética , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , China/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/epidemiologiaRESUMO
AIM: To investigate the survival rate and the level of HaCaT cells damage with ultraviolet B (UVB) radiation at various doses, and observe the protective effects of ginsenoside Rg1 and Rb1 in vitro. METHODS: MTT assay was employed to analyze the cell survival rate after UVB radiation of 30, 60, 90 and 120 mJ x cm(-2). The damage of nucleolus and the protective effects of ginsenoside Rg1 and Rb1 were scanned by Hoechst 33258 staining and single cell gel electrophoresis assay (SCGE). RESULTS: It was found that the cell survival rate decreased gradually and the damage of nucleolus aggravated as the radiation dose increased from 30 mJ x cm(-2) to 120 mJ x cm(-2). At the dose of 20 microg x mL(1-), obvious protective effect of ginsenoside Rg1 and Rb1 can be observed against UVB radiation-induced HaCaT cells growth inhibition and nucleolus damage. CONCLUSION: UVB radiation inhibits HaCaT human keratinocytes growth and ginsenoside Rg1 and Rb1 can relief the damage.
