ABSTRACT
The product of mutated p53 gene is a protein with abnormal conformation, impaired DNA binding, and a prolonged half life, the latter of which results in immunohistochemically detectable levels within nuclei of malignant cells. The present study was aimed at the immunohistochemical determination of p53 overexpression in patients with various histological types of nonHodgkin's lymphomas (NHL), with a particular interest in gastric lymphomas. In these patients, as well as in controls, also serological determinations of p53 protein were performed using an ELISA method. Immunohistochemical overexpression of p53 protein was found in 21% of NHL patients, with the highest incidence of p53 immunoreactivity in cases of Burkitt's lymphoma, follicle center lymphoma grade III, and diffuse large B-cell lymphoma. In gastric lymphomas the overall incidence of p53 immunoreactivity was as high as 46%. Serological ELISA determinations of p53 protein in NHL patients and in controls remained below the lowest detection limit of the method in all 128 cases. Considering that p53 mutations are associated with poor response to therapy, and consequently with poor prognosis, it is of great importance to determine the subset of patients that are particularly at risk for an unfavorable outcome and should be treated more aggressively. Immunohistochemical determinations of p53 overexpression represent a rapid and simple, yet somewhat imperfect technique for an estimation of the frequency of mutational events. On the other hand, serological determinations of p53 protein are completely inadequate for the evaluation of p53 status.
Subject(s)
Lymphoma/metabolism , Tumor Suppressor Protein p53/metabolism , Case-Control Studies , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Lymphoma/blood , Lymphoma/classification , Lymphoma/genetics , Tumor Suppressor Protein p53/bloodABSTRACT
BACKGROUND: Since telomerase activity is detectable in cancer cells but not in some normal somatic cells, it has been considered as a potential diagnostic marker as well as a target for possible anticancer strategies. The purpose of this study was to assess the value of telomerase activity determination in some gynecological tumors and to compare it with the CA 125 tissue and serum profile. PATIENTS AND METHODS: The telomerase activity was determined in 11 gynecological tumors: 7 ovarian carcinomas, 2 carcinomas of the fallopian tube and 2 cervical carcinomas, and compared to the activity in the normal peritoneal tissue of the same patients. Additionally, the levels of CA 125 were measured in the tumor and normal peritoneum tissue samples as well as in the patients' sera. RESULTS: In ovarian tumors, the telomerase activity was detected in 71.4% (5 out of 7), while in the carcinomas of the fallopian tube and cervical carcinomas such activity was not observed. Negative for telomerase activity were also all samples of peritoneum. The range of CA 125 in the tumor tissue was 99 U/g-803667 U/g of tissue and in the normal peritoneum 71 U/g-4925 U/g of tissue. CONCLUSION: In conclusion, telomerase activity could be detected in some of the gynecological tumors, but for clinical use as a diagnostic marker it is inferior to CA 125.
