[Comparison of blood-serum p53 concentrations in patients with advanced breast tumors before and after chemotherapy].

: Investigations of the role of p53 in tumorigenesis and growth, implementation of antitumor effect of cytostatics as well as emergence of tumor resistance have generally received great emphasis. Since most research was mostly concerned with use of tumor tissues, its dynamic aspects were ignored. Our study was concerned with p53 assay of blood serum from 10 patients with advanced breast tumors who underwent tests before and after a second cycle of chemotherapy. Due to immunoblotting technique, p53 was identified in all patients. Its concentration varied significantly and was twice as high in some as compared with the others. Prior to treatment, distinct differences were recorded in content as well as and in the nature of its age-dependent variation after chemotherapy. The highest levels were recorded in the age group over 60 yrs. In most patients (5 out of 6) under 55, post-treatment concentrations rose, on the average, by 13% while in all 4 cases of more than 60, they dropped by an average of 18%.