RESUMO
HOX gene belongs to a highly conserved subgroup of the homeobox superfamily .The HOX genes constitute a family of transcription factors that play key roles in embryonic development , regulating numerous processes , such us cellular growth, differentiation, apoptosis, motility and angiogenesis.The present review shows that there is a close relationship between aberrant expression of HOX genes and malignancy .This article summarizes briofly the advances in the research on HOX genes and their roles in tumor genesis .
RESUMO
In order to understand the effect of retinoic acid (RA) on the craniofacial pattern formation during embryogenesis, we injected RA intraperitoneally into the pregnant female rat on day 11 post coitum (p.c.) and then embryos of day 13 to day 17 p.c. were isolated consequently. The overall morphology and the differential gene expression patterns were analyzed by the microscopic and (DD) RT-PCR methods, respectively. For the morphological study, the retardation of craniofacial region, the shortage of crown rump length and limbs were analyzed in the RA-treated embryos. In the RA-treated embryos of day 17, it was observed that the palatogenesis was completely finished just like in the normal embryos. However, the cleft plate was observed in 36 out of 52 total samples with the distance of cleft palate being 0.80+/-0.36 mm in average. The temporal expression pattern of Hox genes through RT-PCR revealed that the expression of Hoxa7 reached its peak on day 13 then slowly declined in the normal embryos. Whereas in the RA-treated embryos, the expression peak was observed on day 15, then declined subsequently. With the Hoxc8 gene, its expression was low in all stages until the day 16 of normal embryogenesis. On the other hand, Hoxc8 gene expression was detected slightly early on day 15 in the RA-treated embryos. In the study of Bcl-2 family genes, uniformly strong expression of anti-apoptotic and pro-apoptotic genes was observed from day 13 to day 17 of normal embryos, whereas anti-apoptotic gene expressions were decreased after day 16 in the RAtreated embryos. Additionally, a dramatic decline of pro-apoptotic gene expression was observed from day 13 to day 15 of the RA-treated embryos. Therefore, we believe that RA is a potential factor that is actively involved in the cleft palate formation. Moreover, it is profoundly linked with the regulation of Hox and Bcl-2 family gene expression pattern that leads to the embryonic malformation.
Assuntos
Animais , Feminino , Humanos , Gravidez , Ratos , Fissura Palatina , Estatura Cabeça-Cóccix , Desenvolvimento Embrionário , Estruturas Embrionárias , Extremidades , Expressão Gênica , Genes Homeobox , Mãos , Palato , TretinoínaRESUMO
Objective To study the expression of HOXB9 gene in Hela cells,Mocoy cells, SP2/0 cells and U251 cells. Methods The expression of HOXB9 gene was detected by semi-quantitative RT-PCR method. Results Hela cell and U251 cell expressed HOXB9 gene, which SP2/0 cell and Mocoy cell didn't express it. Conclusion The expression of HOXB9 gene was different in different cells.