RESUMO
The prognosis of breast cancer is of major clinical importance and several histopathological, biochemical and immunological variables have been reported to be useful prognostic factors. In the present study, we investigated the clinical significance of the levels of alpha-thymosins in relation to established prognostic factors, both in breast cancer and non-malignant breast lesions, alpha-thymosin levels were measured in breast tissue extracts by specific radioimmunoassays (RIAs) developed for human prothymosin alpha (ProT alpha) and parathymosin alpha (ParaT alpha) and were found to be significantly higher (up to 17.2-fold) in malignant but not in benign breast lesions, as compared to the values of the neighbouring tissues. When alpha-thymosin levels of the tumor samples were correlated with various known prognostic parameters a statistically significant correlation (p < 0.05) was observed between the levels of ProT alpha in malignant tissues to the grade of cancer and the lymph node status of the patient. An association between ProT alpha levels with increase in risk of death from breast cancer was also noticed. These results suggest that the expression of alpha-thymosins in human breast cancer a) depends on the proliferation status of the tumor, b) associates with established prognostic factors describing the metastatic potential of the tumor and c) is related to the overall survival of the patient. The fact that such relationships hold only for cancer tissues encourages the future use of alpha-thymosins as potent prognostic factors in breast cancer.
