RESUMEN
AIMS: To analyse the expression of three homeobox genes (HOXA7, PITX1 and PRRX1) in oral squamous cell carcinomas (OSCC) and the relationship of such expression to certain distinct histopathological features of OSCC and in comparison to adjacent non-neoplastic epithelium (NT). METHODS AND RESULTS: Digoxigenin-labelled riboprobes that are specific for each homeobox gene were generated and in situ hybridization was carried out on frozen sections. In NT samples, HOXA7 and PITX1 transcripts were found more frequently in all epithelial layers, while PRRX1 was expressed in the basal layer. With OSCC samples, expression of the three genes was associated with all histological features. However, the HOXA7 and PITX1 signals were more intense in sheets and nests and PRRX1 in small nests and isolated cells. CONCLUSION: HOXA7, PIXT1 and PRRX1 homeobox genes have different patterns of expression in OSCC depending on its histological features.
Asunto(s)
Carcinoma de Células Escamosas/genética , Proteínas de Homeodominio/genética , Neoplasias de la Boca/genética , Factores de Transcripción Paired Box/genética , Carcinoma de Células Escamosas/patología , Expresión Génica , Perfilación de la Expresión Génica , Humanos , Hibridación in Situ , Neoplasias de la Boca/patología , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
The aim of this study was to standardize a method of DNA extraction from formalin-fixed and paraffin-embedded tissues (PETs) using a salt solution to precipitate protein and isopropanol to precipitate DNA. The samples were submitted to a DNA extraction method in which two different concentrations of ammonium acetate (2 and 4M) were compared with a phenol-chloroform extraction method and with a commercial DNA isolation kit. DNA was qualified and quantified by spectrophotometer analysis, electrophoresis, and amplification by PCR. The 167 and 268bp fragments of APC and beta-globin genes, respectively, were amplified equally from DNA extracted by all tested methods and in all cases. However, the 536bp fragment of beta-globin gene was not amplified in all cases. According to our results, the extraction method using ammonium acetate proved to be simple and suitable for obtaining DNA of good quality, which can be easily amplified by PCR.