Abstract. p53 wild-type is a tumor suppressor gene involved in DNA gene transcription or DNA repair mechanisms. When damage to DNA is unrepairable, p53 induces programmed cell death (apoptosis). The mutant p53 gene is the most frequent molecular alteration in human cancer, including breast cancer. Here, we analyzed the genetic alterations in p53 oncogene expression in 55 patients with breast cancer at different stages and in 8 normal women. We measured by ELISA assay the serum levels of p53 mutant protein and p53 antibodies. Immunohistochemistry and RT-PCR using specific p53 primers as well as mutation detection by DNA sequencing were also evaluated in breast tumor tissue. Serological p53 antibody analysis detected 0/8 (0%), 0/4 (0%) and 9/55 (16.36%) positive cases in normal women, in patients with benign breast disease and in breast carcinoma, respectively. We found positive p53 mutant in the sera of 0/8 (0.0%) normal women, 0/4 (0%) with benign breast disease and 29/55 (52.72%) with breast carcinoma. Immunohistochemistry evaluation was positive in 29/55 (52.73%) with mammary carcinoma and 0/4 (0%) with benign breast disease. A very good correlation between p53 mutant protein detected in serum and p53 accumulation by immunohistochemistry (83.3% positive in both assays) was found in this study. These data suggest that detection of mutated p53 could be a useful serological marker for diagnostic purposes.
The placenta consists largely of fetal tissue, yet at term it displays histological signs of deterioration not apparent in the fetus. To determine whether the apparent degeneration of the placenta is genetically determined, the life-spans of placental cell cultures and the proportion of placental cells capable of incorporating [3H]thymidine for replicative DNA synthesis in vitro were measured. Under the culture conditions employed, the placental cells were removed from the influence of many extrinsic factors thought to play a role in the degeneration of the placenta in vivo. Cultures of fibroblast-like cells derived from the placenta exhibited a reduced life-span and correspondingly reduced proportion of cells able to incorporate [3H]thymidine for DNA synthesis in comparison to cultures derived from the fetal skin and the maternal decidua. These results suggest that intrinsic cellular processes may be involved in the apparent degeneration of the placenta.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.