[Expression and clinical significance of survivin gene and PTEN protein in colorectal adenocarcinoma].

BACKGROUND & OBJECTIVE: The occurrence of colorectal adenocarcinoma is resulted from multiple factors and both survivin gene and PTEN protein take part in these courses. They all regulate cell cycle and apoptosis, but their biological effects are adverse. It is not completely elucidated about their function and relationship in colorectal adenocarcinoma. This study was designed to investigate the role of survivin gene and PTEN protein in the pathogenesis of colorectal adenocarcinoma and their correlation.

METHODS

To determine the survivin mRNA in 42 colorectal adenocarcinoma and 20 adjacent normal colorectal tissue samples, we used reverse transcription polymerase chain reaction (RT-PCR) to determine the expression of survivin mRNA, and immunohistochemical evaluation was used to determine the expression of PTEN protein.

RESULTS

The positive expression rate of survivin was 54.8% in colorectal adenocarcinoma, while no expression was detected in adjacent normal tissue. The expression of survivin gene was significantly correlated with histological differentiation and Dukes stage, but not with gender or lymph node metastasis. The positive rate of PTEN protein in colorectal carcinoma was lower (47.6%) than that in adjacent normal tissue (90.0%). The difference between them was significant (P< 0.01). There was no relationship between PTEN protein and gender, while the expression of PTEN was positively correlated with histological differentiation and lymph node metastasis, and possibly correlated with Dukes stage. With the progress of tumor in malignancy, negative correlation was observed between survivin and PTEN expression in colorectal adenocarcinoma.

CONCLUSION

Survivin gene and PTEN protein are significantly correlated with the clinicopathological characteristics and biologic behaviors in colorectal adenocarcinoma. Detection of survivin together with PTEN is valuable for diagnosing colorectal adenocarcinoma, and evaluating malignancy extent and prognosis.