Prognostic significance of TP53 accumulation in human primary breast cancer: comparison between a rapid quantitative immunoassay and SSCP analysis

Prognostic significance of p53-expression in colorectal carcinoma as measured by a luminometric immunoassay

Background: Mutations of the TP53 gene induce the production of abnormal p53-protein with a prolonged half-life allowing its detection by monoclonal antibodies. In the following study we examined if elevated levels of p53 correlate with worse prognosis in colorectal cancer.

Methods: We have quantified the protein, using an immunoluminometric assay, in 144 cytosols of primary sporadic colorectal cancer tissues and in 96 specimen of normal mucosa.

Results: In 112 samples (77.8%) the p53-expression was higher than the cut-off-value of 0.15 ng p53 per mg total protein. Luminometric immunoassay did not correlate with various clinicopathological parameters. Follow-up ranged from 2.4 to 54.3 (mean 25.3) months. During this period, 61 patients developed recurrences of whom 39 died of the underlying disease. Neither univariate nor multivariate analysis showed any statistically significant differences in prognosis between high and low p53 expression.

Conclusion: Our investigation revealed that p53-overexpression as measured by a luminometric immunoassay, is not a useful predictor of prognosis in patients with colorectal adenocarcinoma. Overcoming the limit of semiquantitative immunohistochemistry for p53-protein quantitative immunoluminometry may be useful elucidating the relation between serum p53-antibodies and p53 in cytosols.

Testing of Functional Integrity of p53 Protein in Primary Breast Cancer by a Rapid Quantitative p53-p21^WAF1 Double Assay May Improve the Clinical Value of p53

We hypothesized that inclusion of p21(WAF1), an indicator of biological function, into the p53 assay might improve the clinical value of p53 in breast cancer diagnosis. In primary breast carcinomas (n = 146) and healthy/benign controls (n = 40), the p53 protein was quantified by luminescence immunoassay. The p21 protein was simultaneously measured by quantitative ELISA in a representative subgroup of breast cancers (n = 52) and controls (n = 17). In controls, p53 but not p21 was detectable. In almost all cancer tissues, p53 and p21 expression could be quantified. There was no correlation between the concentrations of both proteins. However, if p53 exceeded a threshold of 1.0 ng/mg protein, p21 expression was significantly reduced compared with samples with p53 below threshold. p21 was normally distributed in the low-p53 subpopulation, but not in the high-p53 group. The histologic parameter 'grade III' was more often found (p = 0.002) in tumors with p53 >1.0 ng/mg protein than in those with p53 below the threshold. Histological criteria of high tumor malignancy were found more often in cases with high p53 but low p21. Consequently, in clinical routine, a quantitative double assay of p53 and p21(WAF1) might help to discriminate breast cancers with preserved or impaired/lost p53 function.

Prognostic value of p53 molecular status in high-risk primary breast cancer

BACKGROUND

Mutations in the p53 gene are the most common genetic alterations in human primary breast carcinoma and these mutations are often associated with worse prognosis and chemo/radioresistance.

PATIENTS AND METHODS

The analysis of the p53 gene was performed by fluorescence-assisted mismatch analysis in 13 consecutive high-risk primary breast cancer (HR-BC) patients with 10 or more involved axillary nodes to evaluate its prognostic value.

RESULTS

Three p53 mutations (23%) and four allelic variants were detected. After a median follow-up of 52 months the HR-BC disease-free survival (DFS) was 51% and overall survival 79%. All patients harboring a p53 mutation (p53(mut)) relapsed within 10 months of the median DFS while 67% of those showing a wild-type p53 status (p53(wt)) survive disease-free at a median follow-up of 43 months. One p53(mut) patient is still alive while all the p53(wt) patients survive at 56 months median follow-up. Two out of the four p53(wt) relapsing breast cancer patients showed the Arg72Pro allelic variant; one of these died at 75 months.

CONCLUSIONS

p53 mutations may help identify a subset of very high risk breast cancer patients (vHR-BC) with worse prognosis.

TP53 and breast cancer

The TP53 gene (p53) is found altered in breast carcinomas in approximately 20-40% of all cases depending on tumor size and stage of the disease. It seems to be an early event in breast tumorigenesis. Several polymorphisms in the TP53 gene have been detected and their possible roles in breast cancer risk and association to type of cancer developed are discussed. The different mutation spectra seen in geographical and ethnic populations may be used to identify environmental exposure contributing to breast cancer development. The role of TP53 mutation as a prognostic marker is reviewed as well as its role as a predictor for therapy response. All data available on TP53 mutation analyses of human breast carcinomas, as well data from transgenic animal studies and experimental cell studies, support an important role for TP53 in mammary carcinogenesis.

Molecular markers in Paget disease of the breast

BACKGROUND AND OBJECTIVES

Molecular markers are increasingly being analyzed in tumor specimens because of their relevance to both prognosis and choice of therapy. Paget disease of the breast is an uncommon form of breast cancer, in which molecular markers have not been well characterized. The objective of this study was to investigate the expression of c-erbB-2, p53, Ki-67, Cyclin D1, Bcl-2, estrogen receptors (ER), and progesterone receptors (PR) in mammary Paget disease.

METHODS

Archival tumor tissues from 14 patients diagnosed between 1990 and 1999 with Paget disease of the breast were analyzed for these molecular markers by using an automated immunohistochemical assay. Both the intraepidermal Paget cells and the underlying carcinoma were assessed for these markers.

RESULTS

The majority of Paget cells were positive for c-erbB-2 (92.9%), Cyclin D1 (100%), and Ki-67 (85.7%), but very few were positive for Bcl-2 (14.3%). p53 was overexpressed in 42.9% of the cases, and only 28.6% were positive for ER and PR. The rate of expression of these biologic markers was similar in both the Paget cells and the underlying intraductal and/or ductal carcinoma cells.

CONCLUSIONS

Tumors from patients with Paget disease of the breast were positive for c-erbB-2, Cyclin D1, and Ki-67, molecular markers commonly associated with more aggressive tumor behavior and poorer survival in breast cancer patients. Few of these tumors expressed Bcl-2 or ER and PR, which are generally associated with a better prognosis. Similar expression of these markers in both Paget cells and the underlying carcinoma supports the theory that these cells are the result of an intraepidermal spread of ductal carcinoma.

P53 determination alongside classical prognostic factors in node-negative breast cancer: an evaluation at more than 10-year follow-up

BACKGROUND

There is heterogeneity of methods and conflicting results concerning the prognostic value of p53 in node-negative breast cancer. The clinical value of a quantitative method for measuring tumoralp53 content still needs to be evaluated.

PATIENTS AND METHODS

A long-term retrospective study was conducted on 297 node-negative patients with a median follow-up greater than 10 years (11 years, 101-172 months). Classic prognostic factors were considered including age, tumor size, histoprognostic grade and estradiol (ER) and progesterone receptors (PR). In addition, the value of p53 determination (immunoluminometric assay in tumor cytosol) was assessed for this long follow-up period.

RESULTS

p53 concentrations were significantly linked to the histological grade (P = 0.001), to tumor size (P = 0.02) and ER status (P = 0.01). Higher p53 tumoral concentrations were found in tumors with large size, pejorative histological grade and negative ER status. In contrast, p53 tumoral concentrations were not influenced by menopausal or PR status. Multivariate Cox analysis demonstrates that tumor size was the only significant predictor of disease-free survival (P = 0.049) with a risk factor at 1.38. As regards specific survival, univariate Cox analysis indicates that p53 taken as a continuous variable is a significant predictor (P = 0.024) together with histological grade, tumor size and ER status. In a multivariate Cox analysis there were two significant and independent variables for predicting overall survival: tumor size (P = 0.031) and, ER status (P = 0.015) with the highest risk factor (RR = 2.14).

CONCLUSIONS

The present investigation points out that the prognostic power of p53 tumor determination evaluated at more than 10 years median survival is not higher than the well-recognized classic prognostic factors in node-negative breast cancer. The present data highlight the need to assess the prognostic value of potentially new biological factors in node-negative breast cancer on cohorts of patients followed over periods in excess of 10 years.

A prospective trial of midwest breast cancer patients: a p53 gene mutation is the most important predictor of adverse outcome

Several retrospective studies have suggested p53 gene mutation as an adverse prognostic indicator in breast cancer patients, based on a selective growth advantage of p53 mutant cancer cells and their presumed resistance to current adjuvant therapy regimens. A cohort of 90 Caucasian midwestern breast cancer patients was analyzed prospectively (60 months of follow-up) with a rigorous mutation detection methodology. The presence of a p53 gene mutation was the single most adverse prognostic indicator for recurrence (p = 0.0032) and death (p = 0.0001), and was associated with poor response to both adjuvant (p = 0.0001) and palliative (p = 0.006) therapy. Analysis of the p53 gene with appropriate mutation detection methodology markedly improves the prediction of early recurrence, treatment failure, and death in breast cancer patients.

Enhanced prediction of breast cancer prognosis by evaluating expression of p53 and prostate-specific antigen in combination

p53 gene mutation is the most common genetic alteration in neoplastic diseases, including breast cancer, for which p53 alteration may indicate poor prognosis. Recent clinical evidence suggests that prostate-specific antigen (PSA) expression may identify breast cancer patients with favourable outcome. Assessment of p53 and PSA in combination, potentially offering improved prediction, has not yet been performed. Extracts from 952 primary breast carcinomas were assayed for PSA and p53 by quantitative enzyme-linked immunosorbent assays (ELISAs) developed by the authors. Concentrations of each marker were classified as negative or positive on the basis of median and 30th percentile cut-off points for p53 and PSA respectively. Patients followed for a median of 6 years having different combinations of negative or positive status for PSA and p53 were compared with respect to the relative risks (RRs) for relapse and death by Cox proportional hazards regression analysis, in which an interaction term was also evaluated, and with respect to disease-free survival (DFS) and overall survival (OS) probabilities by Kaplan-Meier plots and log-rank tests. Multivariate models were adjusted for oestrogen and progesterone receptor status, nodal status, patient age, tumour size, DNA ploidy, S phase fraction and receipt of chemotherapy. Interactions were not found between the status of PSA and p53 in the Cox models, in which PSA-negativity (RR = 1.47, P = 0.020 for DFS, and RR = 1.49, P = 0.023 for OS) and p53-positivity (RR = 1.46, P = 0.017 for DFS, and RR = 1.41, P = 0.033 for OS) were individually associated with prognosis. Evaluation of a combined three-level variable revealed that PSA(-)/p53(+) patients had significantly higher risks for relapse (RR = 2.13, P < 0.001) and death (RR = 2.08, P = 0.001) than PSA(+)/p53(-) patients, and that patients positive or negative for both markers had intermediate risks for the outcome events in the same multivariate analysis (RR = 1.45 for both DFS and OS). The results of our study demonstrate that the assessment of combined PSA and p53 expression status by ELISAs, easily applicable to breast tumour extracts prepared for steroid hormone receptor analyses, may stratify breast cancer patients into groups differing by relapse and death risks of greater magnitude than offered by the assessment of either p53 or PSA alone.

Prognostic value of uPA and p53 accumulation measured by quantitative biochemical assays in 1245 primary breast cancer patients: a multicentre study

The purpose of this retrospective multicentre study was to assess the prognostic value of urokinase plasminogen activator (uPA) and p53 levels in a large series of primary breast cancer, using an automatic quantitative luminometric method. Samples of 1245 operable breast tumours were collected from seven French institutions and patients were followed for a median of 75 months. The median uPA and p53 levels assayed in cytosols by means of the immunoluminometric technique (LIA) were 0.31 and 0.20 ng mg(-1) of protein respectively. In univariate analysis, high levels of uPA and p53 were associated with shorter disease-specific survival, disease-free interval, and distant recurrence-free interval. The 5-year survival rates were 95.5% among patients with uPA values below the 20th percentile, and 77.5% in those with values above the 80th percentile. The 5-year survival rates were 91.0% in patients with p53 values below the 20th percentile, and 77.6% in those with values above the 80th percentile. In multivariate analysis, the risk of disease-related death increased with uPA levels after adjustment for tumour size, histological grade, lymph node involvement, and estrogen receptor status. A high level of uPA was also related to a shorter disease-free interval and distant recurrence-free interval. In node-negative patients, a high level of uPA remained strongly related to the three outcomes. When adjusted for other prognostic factors, p53 was no longer significantly related to the outcomes. Given its rapidity and simple application to routinely prepared cytosols, this LIA may be useful for evaluating the prognostic impact of uPA in primary breast cancer, particularly in node-negative patients. According to our results, the prognostic value of p53 accumulation is limited when uPA is included in multivariate analysis.

Prognostic and predictive value of p53 and p21 in breast cancer

The prognostic and predictive value of p53 has been extensively studied in breast cancer. p53 serves a multifunctional role as a transcriptional regulator, genomic stabilizer, inhibitor of cell cycle progression, facilitator of apoptosis, and also perhaps an inhibitor of angiogenesis. Abrogation of its function should therefore lead to a more aggressive breast cancer phenotype and a worse clinical outcome, and indeed the preponderance of studies confirm this, with the risk of recurrence and death increasing by 50% or more if p53 is abnormal. Lack of unanimity of results may be due to differences in technique, study design, or population, as well as the subjectivity inherent in some approaches; however, the complexity and random nature of genomic change present in cancer cells may well also contribute to the lack of unanimity. Because many anticancer agents may exert a therapeutic effect through genomic damage and subsequent triggering of apoptosis, and because p53 can respond to genomic damage and facilitate apoptosis, it can be hypothesized that an intact p53 would predict sensitivity to therapy. Present data in breast cancer, however, does not clearly indicate that this is the case. There are several potential explanations. Study designs to accurately test the predictive value of a molecular marker are more exacting and difficult to achieve than prognostic studies. There may also be multiple alternative pathways, not involving p53, that play a part in determining the therapeutic effect of a treatment. The prognostic value of a downstream effector of p53 has also been assessed, though less extensively. p21 is transcriptionally upregulated by p53 and is an inhibitor of cyclin-dependent kinases and thus of cell cycle progression. Higher levels of p21 might indicate a more indolent type of breast cancer. However, data from a number of clinical studies is very conflicting, and at present p21 is not a promising prognostic factor in breast cancer.

Recurrence in meningeal hemangiopericytomas

BACKGROUND

Meningeal hemangiopericytomas are more aggressive than typical meningiomas, with a high rate of recurrence and distant metastases. The question of whether a correlation exists between prognosis and histologic features remains controversial.

CASE DESCRIPTION

We report two cases of recurrent meningeal hemangiopericytomas. Although local growth control of the tumor was obtained by tumor removal and irradiation in a 38-year-old male patient (Case 1) with a recurrent tentorial tumor, the tumor disseminated and metastasized extracranially within a short period after treatment, leading to rapid deterioration. Another 38-year-old female patient (Case 2) with a recurrent orbital tumor had a favorable outcome after tumor removal. The Ki-67 proliferative index using the MIB-1 monoclonal antibody increased as the tumor recurred in Case 1 (2.5%, 7.9%, and 15.7%), but did not change between primary and recurrent tumors of Case 2 (4.2%, 3.1%). Immunostaining for p53 protein in Case 1 was negative at the first resection, and became positive at the second and third resections, whereas in Case 2, it was negative in both the primary and recurrent tumors.

CONCLUSIONS

Our results suggest that p53 protein accumulation with a high proliferative potential is a useful marker to estimate malignant progression in meningeal hemangiopericytomas.

Comparison between p53 protein measurements using the luminometric immunoassay and immunohistochemistry with detection of p53 gene mutations using cDNA sequencing in human breast tumors

The p53 mutational status of 226 representative primary breast cancer samples, derived from a population-based cohort, was analyzed using cDNA-based sequencing. The results were compared with those obtained with immunohistochemistry (IHC) on microwave-treated paraffin sections and the p53 specific luminometric immunoassay (LIA) on cytosols, all from the same individuals. Thirty-seven mutations were found using cDNA sequencing and were categorized into A) missense mutations in the evolutionarily conserved regions; B) missense mutations outside the evolutionarily regions; and C) deletions, insertions and nonsense mutations. Using optimal cut-off values, LIA detected 15 of 16 missense mutations in category A, in which IHC detected all 16. In category B, 10 of 13 and 7 of 13 mutations were detected, respectively. Some of the samples in category A had a very high p53 protein content when measured with the LIA, the reason for this being discussed. IHC detected 0 of 5 stop codon and 0 of 3 deletions/insertions mutations, while the LIA method detected 2 of 5 stop codon mutations and 1 of 3 deletion/insertion mutations. Compared with cDNA sequencing, protein analyses using optimal cut-off values resulted in an overall sensitivity and specificity of 64.9% and 89.9%, respectively, for the LIA method. Corresponding values were 72.2% and 92% for IHC. In addition, patients from whom p53 mutations could be detected by cDNA sequencing had a statistically significant (p = 0.0137) shorter survival, which was not readily apparent using the alternative LIA or IHC approaches at optimal cut-off values.

Immunofluorometrically determined p53 accumulation as a prognostic indicator in Italian breast cancer patients

The prognostic value of p53 protein accumulation in breast cancer, especially as detected by methods other than immunohistochemistry, has not been established unequivocally. A sensitive immunofluorometric assay of p53 protein employing DO-1 and CM-1 antibodies was used in this study to assay extracts of 171 breast carcinomas from northern Italy. p53 over-expression, demonstrated in 36 (21%) tumours, was associated with lack of oestrogen receptor (ER) expression but was not related to patient age, stage, lymph node status, tumour size, histologic type, grade or progesterone receptor (PR) expression status in contingency tables. An increased risk for cancer relapse of p53-positive patients compared to p53-negative patients was determined using multivariate Cox regression analysis, which also showed that p53 protein over-expression was an independent predictor of reduced disease-free survival in node-positive and ER+ patients but not in node-negative or ER- individuals. The equivalent analysis for assessing the impact of p53 status on overall survival was not statistically significant, possibly reflecting the short patient follow-up. Our results suggest that an immunoassay of p53 protein, applicable to cytosolic extracts prepared for steroid hormone receptor analyses, may provide information for breast cancer prognosis.

Mutations in residues of TP53 that directly contact DNA predict poor outcome in human primary breast cancer

The tumour-suppressor gene TP53 is frequently mutated in breast tumours, and the majority of the mutations are clustered within the core domain, the region involved in DNA binding. We searched for alterations in this central domain of the TP53gene in 222 human breast cancer specimens using polymerase chain reaction-single-strand conformation analysis (PCR-SSCA) followed by sequencing. TP53 gene mutations were observed in 66 tumours (31%), including three tumours that contain two mutations. Fifty-four (78%) of these mutations were missense point mutations, one was a nonsense mutation and four were deletions and/or insertions causing disruption of the protein reading frame, whereas four mutations were either silent or a polymorphism (at codon 213; n = 6). Interestingly, the majority of missense mutations were observed at codon 248. The outcome has been related with patient and tumour characteristics, and with prognosis in 177 patients who were eligible for analysis of both relapse-free and overall survival (median survival for patients alive was 115 months). There was no significant association between the frequency of TP53 mutations and menopausal or nodal status, or tumour size. In a Cox univariate analysis, TP53 gene mutation was significantly associated with poor relapse-free survival (RFS: P = 0.02) but not with overall survival (OS: P = 0.07). In a Cox multivariate analysis, including classical prognostic factors, TP53 gene mutation independently predicted poor RFS and OS (RHR = 1.8 and 1.6 respectively). Unexpectedly, the median relapse-free survival of patients with a polymorphism at codon 213 or with a silent mutation was shorter (median 11 months) than the median relapse-free survival of patients with or without a TP53 gene mutation (median 34 or 48 months respectively). In an exploratory subset analysis, mutations in codons that directly contact DNA were related with the poorest relapse-free (P < 0.05) and overall survival (P < 0.02). These data imply that in the analysis of the prognostic value of TP53, the type of mutation and its biological function should be considered.

Expression of interleukin-1beta in human breast carcinoma

BACKGROUND

Interleukin 1beta (IL-1beta) is a multifunctional cytokine that up-regulates the inflammatory response. It is not known whether IL-1beta plays a major role in human malignancy. To determine whether IL-1beta might be involved in breast carcinoma progression, the authors measured the IL-1beta content in tissue extracts from >200 invasive breast carcinomas and smaller numbers of ductal carcinoma in situ (DCIS) and benign lesions.

METHODS

IL-1beta content was measured by an enzyme-linked immunoadsorbent assay and analyzed to determine whether these values were correlated with the contents of scatter factor (SF) (an invasogenic and angiogenic cytokine), von Willebrand's factor (VWF) (a marker of endothelium), thrombospondin-1 (TSP1) (an antiadhesive and antiangiogenic glycoprotein), and tumor necrosis factor-alpha (TNF alpha) (another proinflammatory cytokine). Studies were also performed to determine whether IL-1beta content was correlated with other pathologic and immunochemical variables that have been utilized or proposed as prognostic indicators for breast carcinoma.

RESULTS

The most important findings of these studies were: 1) immunoreactive IL-1beta was detected in approximately 90% of invasive breast carcinomas; 2) IL-1beta levels were significantly higher in invasive carcinomas than in a group of DCIS and benign lesions; 3) high IL-1beta content in invasive carcinomas was significantly associated with higher contents of SF, VWF, and TSP1, but not TNF alpha; and 4) there was a trend toward higher IL-1beta content in invasive carcinomas with a group of other parameters that suggest a biologically more aggressive tumor (estrogen receptor negativity, high tumor grade, p53 positivity, and bcl-2 negativity); and the proportion of invasive tumors with these characteristics was significantly increased in a subgroup of tumors having very high IL-1beta content. The authors also found a correlation between high IL-1beta content and CD68 positivity, suggesting that macrophages may account for some of the IL-1beta present in human breast carcinoma tissue.

CONCLUSIONS

These findings suggest that significant titers of IL-1beta are present within the microenvironment of most breast carcinomas and that a high IL-1beta content is often associated with tumor invasiveness and with other pathologic features suggestive of an aggressive tumor biology.