Significance Of P53 Overexpression Research Articles

Prognostic significance of p53 overexpression in luminal HER2-negative type breast cancer.

35 Background: In this study, we evaluated the prognostic significance of p53 overexpression, because it was reported that there was a significant correlation between p53 and resistance to endocrine therapy, and prognosis. Methods: A retrospective analysis was performed using 2,332 primary breast cancer patients who underwent surgery between 2001 and 2010. There were 1,899 cases with luminal subtypes (905 cases: HER2-negative and Ki67 low type; 808 cases: HER2-negative and Ki67 high type; and, 186 cases: HER2-positive type), 155 cases with HER2-enriched subtypes, and 278 cases with triple-negative subtypes. Luminal type was defined as ER-positive cell rates ≥ 1%, regardless of PgR status. The cut-off value of the Ki67 index was 20%. Moreover, tumor size, nodal status and nuclear grade were studied in relation to disease free (DFS) and overall survival (OS) using the Cox proportional hazard model. Results: We found that p53 overexpression was present in 10% of the patients and significantly correlated with larger tumors, younger age, positive nodes, a higher grade, negative ER/PgR, a higher Ki67, and positive HER2. The patients with p53 overexpression had significantly unfavorable prognosis, especially in the patients who only received endocrine therapy. There were 26 cases in the luminal HER2 negative and Ki67 low type group that had p53 overexpression and showed a significantly shorter DFS. In the univariate analysis for DFS, p53, Ki67, tumor size, nuclear grade and nodal status were significant factors in luminal HER2 negative type. In the subsequent multivariate analysis for DFS, the p53 status was one of the most significant factors. Conclusions: The p53 overexpression was a significant prognostic factor in luminal type breast cancer. Therefore, the prognostic evaluation of luminal HER2 negative type breast cancer might be improved using an immunopanel, which includes Ki67 and p53. Moreover, it might isolate the patients who are resistant to endocrine therapy.

O113 Head and neck squamous cell carcinoma in non-smoking and non-drinking patients with multiple tumors: etiologic significance of p53 overexpression and ki-67 suprabasal expression in non tumorous epithelium

O113 Head and neck squamous cell carcinoma in non-smoking and non-drinking patients with multiple tumors: etiologic significance of p53 overexpression and ki-67 suprabasal expression in non tumorous epithelium

Overexpression of p53 Protein Associated with Proliferative Activity and Histological Degree of Malignancy in Solar Keratosis

Background: Overexpression of p53 protein has frequently been demonstrated in human epithelial neoplasms including squamous cell carcinoma (SCC) and solar keratosis (SK). SK is a precursor lesion of SCC. In SCC of the skin, we have already reported that overexpression of p53 protein is associated with the proliferative activity, which is indicated by the percentage of Ki-67-positive cells. In SK, however, the significance of p53 overexpression is still unclear. Objective: The aim of the present study was to clarify the relationship between p53 overexpression and proliferative activity, and between p53 overexpression and histological degree of malignancy in SK. Methods: Sixty-eight cases of SK were divided into four grades according to the proportion of atypical cells in the epidermis (in grade I, up to 25% of the epidermal cells are atypical, in grade II 25–50%, in grade III 50–75%, in grade IV more than 75%) and were immunohistochemically analyzed for the expression of p53 protein and Ki-67 antigen. Results: p53 overexpression was detected in 58 out of the 68 cases of SK. The percentage of p53-protein-positive cells (DO-7 index) ranged from 0 to 78.8 (mean ± SD = 20.6 ± 21.6). Mean DO-7 indices were 7.9 in grade I, 26.7 in grade II and 38.3 in grade III. The differences in mean DO-7 index between grades I and II and between grades I and III were statistically significant (p < 0.001). The percentage of Ki-67-antigen-positive cells (MIB-1 index) ranged from 0.8 to 38.2 (mean ± SD = 10.5 ± 9.0). Mean MIB-1 indices were 5.9 in grade I, 10.7 in grade II and 20.5 in grade III. The differences in the mean MIB-1 index between grades I and II and between grades II and III were statistically significant (p < 0.01). Cases with higher DO-7 indices tended to show higher MIB-1 indices, and the relation was statistically significant [y = 0.272x + 4.8; correlation coefficient r = 0.59 > r (n – 2, 0.01) = 0.31]. Conclusion: Overexpression of p53 protein was related to cell proliferation as well as histological degree of malignancy in SK. Dysfunction of p53 protein might be implicated in skin carcinogenesis.

Significance of p53 overexpression in bone marrow biopsies from patients with bone marrow failure: aplastic anemia, hypocellular refractory anemia, and hypercellular refractory anemia.

Among patients with bone marrow failure, differentiating acquired aplastic anemia (AA) from hypocellular refractory anemia (hypo RA) can be a difficult and challenging task. Morphological, cytochemical, immunocytochemical, and cytogenetic studies may provide tools for discriminating between both entities. In addition, differences in the pattern of proliferation and apoptosis of bone marrow cells in AA and in the myelodysplastic syndrome have been reported. Because of the correlation between p53 and apoptosis, we examined the overexpression of p53 on bone marrow biopsies in RA and AA. Our study included 14 patients with hypo RA, 14 patients with hypercellular (hyper) RA, ten patients with classic acquired AA, and 37 hematologically normal individuals. p53 was overexpressed in eight (57%) hypo RA patients and 11 (79%) hyper RA patients. All normal individuals and patients with AA showed no overexpression of p53 in their marrow. These results were statistically significant:p < 0.01 (AA vs hypo RA), p<0.001 (AA vs hyper RA), while the difference between hypo RA and hyper RA was not statistically significant. We conclude that p53 overexpression in bone marrow biopsies is a valuable tool for studying bone marrow failure and may provide additional information to help differentiate hypo RA from acquired AA.

Significance of p53 Overexpression in Urinary Bladder Transitional Cell Carcinoma In Situ Before and After Bacillus Calmette-Guerin Treatment

No AccessJournal of UrologyUrological Survey: Abstracts: Principles of Oncology and Immunology, and Tumors of Bladder, Penis and Urethra1 May 1998Significance of p53 Overexpression in Urinary Bladder Transitional Cell Carcinoma In Situ Before and After Bacillus Calmette-Guerin Treatment K. Ick, M. Schultz, P. Stout, and K. Fan K. IckK. Ick More articles by this author , M. SchultzM. Schultz More articles by this author , P. StoutP. Stout More articles by this author , and K. FanK. Fan More articles by this author View All Author Informationhttps://doi.org/10.1097/00005392-199805000-00117AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "Significance of p53 Overexpression in Urinary Bladder Transitional Cell Carcinoma In Situ Before and After Bacillus Calmette-Guerin Treatment." The Journal of Urology, 159(5), pp. 1768–1769 Departments of Urology and Pathology, University of Arkansas Medical Sciences Campus and John L. McClellan Memorial Veterans Affairs Hospital, Little Rock, Arkansas.© 1998 by American Urological Association, Inc.FiguresReferencesRelatedDetails Volume 159Issue 5May 1998Page: 1768-1769 Advertisement Copyright & Permissions© 1998 by American Urological Association, Inc.MetricsAuthor Information K. Ick More articles by this author M. Schultz More articles by this author P. Stout More articles by this author K. Fan More articles by this author Expand All Advertisement Loading ...

Significance of p53 overexpression in urinary bladder transitional cell carcinoma in situ before and after bacillus Calmette-Guérin treatment

Objectives. Overexpression of p53, normally secondary to gene mutation, in invasive uroepithelial neoplasms (transitional cell carcinoma) and a high percentage of transitional cell carcinoma in situ (CIS) has been described; however, the role of p53 before and after bacillus Calmette-Guérin (BCG) treatment of CIS needs to be defined. Methods. Immunohistochemical reaction for p53 overexpression was performed on 12 patients with CIS before and after BCG treatment. Thirty cystectomy specimens with invasive TCC were also evaluated for the presence of CIS, hyperplasia, and dysplasia. Results. Twenty-three cases of CIS were identified. Approximately 90% of CIS cases (21 of 23) were positive for p53 overexpression, whereas transitional cell hyperplasia was uniformly negative. Less than 5% of the cells in morphologically dysplastic lesions were positively stained. Ten of 12 CIS patients displayed p53 overexpression before BCG treatment. After BCG treatment, 4 patients displayed residual CIS with p53 overexpression, and 8 patients showed no residual CIS or p53 overexpression. Three of the 4 patients with residual CIS and overexpression rapidly developed invasive transitional cell carcinoma requiring cystectomy. The 1 remaining patient was treated with a second course of BCG; further biopsies displayed the development of grade 1 papillary transitional cell carcinoma without invasion, and the patient is currently being followed. Conclusions. Our data suggest that follow-up biopsy procedures are essential in all patients with CIS treated with BCG. The biopsy specimens should be evaluated for p53 overexpression, because our data indicate that persistent p53 overexpression in uroepithelial lesions after BCG treatment is an ominous finding for probable tumor progression.

Prognostic and diagnostic significance of p53 overexpression in gastric cancer—how we can use a new molecular marker in clinical practice

Prognostic and diagnostic significance of p53 overexpression in gastric cancer—how we can use a new molecular marker in clinical practice