RESUMO
Numerous epidemiological studies have evaluated the association between transforming growth factor beta receptor type 1 (TGFBR1) polymorphisms and the risk of cancer; however, the results remain inconclusive and controversial. To determine the association between breast cancer risk and the *6A polymorphism of the TGFBR1 gene, a case-control study of 280 breast cancer patients and 280 controls was performed in Iranian women. Our study demonstrates that women who carry the TGFBR1*6A allele are at lower risk of developing breast cancer. The highest protection against breast cancer was observed in 6A/6A homozygotes (OR = 0.32, p = 0.04). A lower frequency of the TGFBR1*6A allele in breast cancer patients may be an important genetic determinant that contributes to a lower risk of breast cancer in Iranian women. The results also showed that the allelic length of TGFBR1 polymorphisms had no significant association with the age at onset or the grade of disease, nor with the expression of progesterone and estrogen receptors and HER2.
Assuntos
Neoplasias da Mama/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Irã (Geográfico) , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Proteção , Receptor do Fator de Crescimento Transformador beta Tipo I , Repetições de Trinucleotídeos , Adulto JovemRESUMO
BACKGROUND: Recently, we have shown that peroxisomal protein expression was induced upon retinoic acid treatment in mouse embryonic stem cells during the process of neurogenesis. Thus, characterization of the respective promoter could elucidate the molecular aspects of transcriptional regulation of this gene. METHODS: Using the conventional software programs for promoter prediction, a putative promoter region was identified approximately 561 bp upstream of the peroxisomal protein coding sequence. In order to clone this region with a GC-content of 71.01%, a cocktail of ammonium sulfate buffer supplied with two additive components, betaine and dimethyl sulfoxide, and a high concentration of MgCl(2) was used. RESULTS: The modulated polymerase chain reaction composition significantly improved the amplification of GC-rich DNA target sequences. Improved amplification of this region was due to reduction in the formation of secondary structures by the GC-rich region. CONCLUSION: Therefore, this polymerase chain reaction composition could be generally used to facilitate the amplification of other GC-rich DNA sequences as verified by amplification of different GC rich regions.
