Occurrence and expression of p53 suppressor gene and c-Myc oncogene in dog eyelid tumors.
OBJECTIVE
To detect the occurrence and expression of the suppressor gene p53 and of the oncogene c-Myc in eyelid tumors of dogs using the PCR, RT-PCR, PCR-ELISA and RT-PCR-ELISA techniques. These genes have not been described in dog eyelid tumors before.


METHODS
Nine samples of eyelid or third eyelid epithelial tumors were obtained from the archives of the Department of Veterinary Pathology. Tumor diagnosis was confirmed by evaluation of hematoxylin-eosin stained sections, and immunohistochemistry for cytokeratin AE1/AE3 and vimentin V9. A canine mammary tumor was used for positive control. Agarose gel electrophoresis, PCR-ELISA and RT-PCR-ELISA were used to detect p53 and c-Myc genes.


RESULTS
The occurrence of p53 was detected in most of the eyelid tumors and third eyelid tumors studied (88.8%, n = 8) and was expressed in 75% of the positive samples, as indicated by ELISA. The c-Myc gene was found in 77.7% (n = 7) of the samples and was expressed in eight samples.


CONCLUSIONS
Eyelid and third eyelid tumors of dogs express both the p53 and the c-Myc genes as shown by PCR and RT-PCR. However, PCR ELISA and RT-PCR ELISA were more efficient in assessing occurrence and expression of these genes because they identified amplified products that were not detected by agarose gel electrophoresis.
Lopes
Rodrigo Antonio
RA
Postgraduate Programme in Animal Science, Faculty of Odontology, Veterinary Science Course, Unesp, State of São Paulo University, Araçatuba-SP, Brazil.
Cardoso
Tereza Cristina
TC
Luvizotto
Maria Cecília Rui
MC
de Andrade
Alexandre Lima
AL
D000818:Animals; D004247:DNA / Q000235:genetics; D004283:Dog Diseases / Q000378:metabolism*; D004285:Dogs; D005142:Eyelid Neoplasms / Q000378:metabolism / Q000662:veterinary*; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism*; D012313:RNA / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
D016271:Proto-Oncogene Proteins c-myc; D016159:Tumor Suppressor Protein p53; D012313:RNA; D004247:DNA