p53 as a potential predictive factor of response to chemotherapy: feasibility of p53 assessment using a functional test in yeast from trucut biopsies in breast cancer patients

Expression of WWOX and p53 in gastric cancer

AIM: To examine the expression of WWOX and p53 proteins in gastric cancer, and to analyze the possible mechanisms behind the malignant growth of gastric cancer.

METHODS: The expression of WWOX and p53 proteins was detected by immunohistochemistry in 70 paraffin-embedded samples of gastric cancer and 20 tumor-adjacent normal tissue samples. Statistical analyses were then performed to analyze the relationship between WWOX and p53 expression and clinicopathologic parameters of gastric cancer.

RESULTS: The positive rate of expression of p53 protein in gastric cancer was significantly higher than that in normal gastric tissue (51.42% vs 0.00%, P < 0.05). Expression of p53 protein in gastric cancer was related with depth of invasion, lymph node metastasis, and tumor clinical stage (all P < 0.05). The positive rate of expression of WWOX protein was significantly lower in gastric cancer than in normal gastric tissue (41.43% vs 90.00%, P < 0.05). Expression of WWOX protein in gastric cancer was related with depth of invasion and clinical stage, but not with lymph node metastasis. There is a negative correlation between WWOX and p53 expression in gastric cancer.

CONCLUSION: Detection of expression of p53 protein and WWOX proteins might be useful for early diagnosis and evaluation of prognosis of gastric cancer.

Prognostic and predictive value of TP53 mutations in node-positive breast cancer patients treated with anthracycline- or anthracycline/taxane-based adjuvant therapy: results from the BIG 02-98 phase III trial

INTRODUCTION

Pre-clinical data suggest p53-dependent anthracycline-induced apoptosis and p53-independent taxane activity. However, dedicated clinical research has not defined a predictive role for TP53 gene mutations. The aim of the current study was to retrospectively explore the prognosis and predictive values of TP53 somatic mutations in the BIG 02-98 randomized phase III trial in which women with node-positive breast cancer were treated with adjuvant doxorubicin-based chemotherapy with or without docetaxel.

METHODS

The prognostic and predictive values of TP53 were analyzed in tumor samples by gene sequencing within exons 5 to 8. Patients were classified according to p53 protein status predicted from TP53 gene sequence, as wild-type (no TP53 variation or TP53 variations which are predicted not to modify p53 protein sequence) or mutant (p53 nonsynonymous mutations). Mutations were subcategorized according to missense or truncating mutations. Survival analyses were performed using the Kaplan-Meier method and log-rank test. Cox-regression analysis was used to identify independent predictors of outcome.

RESULTS

TP53 gene status was determined for 18% (520 of 2887) of the women enrolled in BIG 02-98. TP53 gene variations were found in 17% (90 of 520). Nonsynonymous p53 mutations, found in 16.3% (85 of 520), were associated with older age, ductal morphology, higher grade and hormone-receptor negativity. Of the nonsynonymous mutations, 12.3% (64 of 520) were missense and 3.6% were truncating (19 of 520). Only truncating mutations showed significant independent prognostic value, with an increased recurrence risk compared to patients with non-modified p53 protein (hazard ratio = 3.21, 95% confidence interval = 1.740 to 5.935, P = 0.0002). p53 status had no significant predictive value for response to docetaxel.

CONCLUSIONS

p53 truncating mutations were uncommon but associated with poor prognosis. No significant predictive role for p53 status was detected.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00174655.

Guidelines to assure quality in breast cancer surgery

The outcome of breast cancer surgery, with respect to cosmetic results, loco regional control and prognostic information from nodal staging, may vary substantially. Optimal breast cancer care starts with a proper surgical act, which can only be performed when optimal imaging and preoperative diagnosis are available. Next, on the basis of all peroperative findings, the right surgical procedure should be indicated after multidisciplinary consultation and discussion, keeping the objective of the final outcome in mind. The surgical act itself is best performed by an experienced surgeon who has maintained their experience after sufficient training. The outcome of the different procedures can be measured according to simple criteria and prospective registration. All possible surgical procedures, the indication-objectives, the training-objectives and outcome measures are described.

Rapid and sensitive p53 alteration analysis in biopsies from lung cancer patients using a functional assay and a universal oligonucleotide array: a prospective study

PURPOSE

Molecular profiling of alterations associated with lung cancer holds the promise to define clinical parameters such as response to treatment or survival. Because <5% of small cell lung cancers and <30% of non-small cell lung cancers are surgically resectable, molecular analysis will perforce rely on routinely available clinical samples such as biopsies. Identifying tumor mutations in such samples will require a sensitive and robust technology to overcome signal from excess amounts of normal DNA.

EXPERIMENTAL DESIGN

p53 mutation status was assessed from the DNA and RNA of biopsies collected prospectively from 83 patients with lung cancer. Biopsies were obtained either by conventional bronchoscopy or computed tomography-guided percutaneous biopsy. Matched surgical specimens were available for 22 patients. Three assays were used: direct sequencing; a functional assay in yeast; and a newly developed PCR/ligase detection reaction/Universal DNA array assay.

RESULTS

Using the functional assay, p53 mutation was found in 62% of biopsies and 64% of surgical specimens with a concordance of 80%. The sensitivity of the functional assay was determined to be 5%. Direct sequencing confirmed mutations in 92% of surgical specimens but in only 78% of biopsies. The DNA array confirmed 100% of mutations in both biopsies and surgical specimens. Using this newly developed DNA array, we demonstrate the feasibility of directly identifying p53 mutations in clinical samples containing <5% of tumor cells.

CONCLUSIONS

The versatility and sensitivity of this new array assay should allow additional development of mutation profiling arrays that could be applied to biological samples with a low tumor cell content such as bronchial aspirates, bronchoalveolar lavage fluid, or serum.

Prognostic Values of p53 and HER-2/neu Coexpression in Invasive Bladder Cancer in Taiwan

OBJECTIVES

To explore the clinical significance of p53 and HER-2/neu coexpression by immunohistochemistry in patients with invasive bladder cancer in Taiwan.

METHODS

Paraffin-embedded tumor blocks were obtained from 67 patients with invasive bladder cancer subjected to radical cystectomy, bilateral lymph node dissection, and urinary diversion with or without systemic chemotherapy. Two observers (N.H.C. and T.S.T.), blinded to clinical outcome, reviewed the immunohistochemical staining for p53 (PAb1801) and HER-2/neu (Ab-17). The results were analyzed for progression-free survival and patient survival.

RESULTS

Positive staining for p53 and HER-2/neu was found in 30 (44.8%) and 39 (58.2%) patients. In contrast to HER-2/neu, p53 expression was significantly associated with tumor grade and pathologic stage (p = 0.040 and 0.004, respectively), and tended to be related to the nodal status (p = 0.080). Most importantly, coexpression of p53 and HER-2/neu significantly correlated with nodal metastases (p = 0.020). Univariate and multivariate analysis revealed p53 and nodal status as two independent prognostic factors. Additionally, patients with p53 and HER-2/neu coexpression had the shortest time to relapse and overall survival, irrespective of whether adjuvant chemotherapy was given or not (p = 0.005 and 0.030).

CONCLUSIONS

In invasive bladder cancer, p53 was an important prognostic factor since its expression correlated with tumor grade and stage, even nodal status, whereas HER-2/neu did not show prognostic significance. Tumors with p53 and HER-2/neu coexpression were associated with nodal metastases, probably resulting in decreased progression-free survival. Although some basic studies provide some important supports, studies including larger patient cohorts would still be required to prove the hypothesis that p53 and HER-2/neu-coexpressing tumors have a worse prognosis and are more resistant to a cisplatin-based multidrug regimen.

Locally advanced/inflammatory breast cancers treated with intensive epirubicin-based neoadjuvant chemotherapy: are there molecular markers in the primary tumour that predict for 5-year clinical outcome?

BACKGROUND

Locally advanced and/or inflammatory breast cancer (LABC) is a heterogeneous disease. Molecular markers may help to understand this heterogeneity. This paper reports the results of a study assessing the potential prognostic or predictive value of HER-2, p53, cyclinD1, MIB1, ER and PgR expression by immunohistochemistry from patients included in an EORTC-NCIC-SAKK trial.

PATIENTS AND METHODS

A total of 448 patients with a cytological or histological diagnosis of LABC were randomised into a trial comparing two anthracycline-based neoadjuvant regimens. Chemotherapy was followed by standard locoregional therapy. Survival was comparable in both arms. We collected and analysed centrally paraffin-embedded tumour specimens from 187 (72.5%) of 258 patients that had a histological diagnosis.

RESULTS

Of the patients included in this molecular marker study 114 relapsed and 91 died. In the multivariate analysis p53 positivity was associated with a shorter progression-free survival [hazard ratio (HR) = 1.96; 95% CI 1.33-2.91; P = 0.0008) and a shorter overall survival (HR = 1.98; 95% CI 1.28-3.06; P = 0.002). PgR positivity predicted for a longer overall survival (HR = 0.54; 95% CI 0.35-0.83; P = 0.0045).

CONCLUSIONS

p53 was an independent factor predicting for survival. In order to clarify whether p53 is a pure prognostic and/or a predictive factor, a phase III trial is being conducted (EORTC 10994/BIG 00-01 study) using functional assay in yeast from frozen tumour samples.

Correlations of Breast Carcinoma Biomarkers and p53 Tested by FASAY and Immunohistochemistry

p53 status is an important predictive factor in breast cancer, but the results of many studies are ambiguous. We tested p53 by functional analysis of separated alleles in yeast (FASAY) as well as by immunohistochemistry (IHC) and evaluated correlations with main prognostic factors, proliferation, and Bcl-2. Thirty-two tumors were tested with antibodies BP53-12, DO1, DO11, DO12, and by FASAY. Spearman rank correlations were tested separately with age, tumor type, pT, grade, pN, NPI, Ki-67, S-phase, proliferation index, Bcl-2, and steroid receptor status determined by ER, PR, and pS2. FASAY showed significant correlations with ductal type, grade and proliferation, and an inverse correlation with functional estrogen receptor and Bcl-2. FASAY provided better correlations compared to p53 IHC. We conclude that FASAY shows significant correlations with main prognostic/predictive factors and provides more reliable biological information compared to p53 IHC. Apoptosis is positively linked to proliferation and is not under the control of p53, which is frequently mutated in highly proliferating carcinomas. FASAY seems to be very important in assessing the predictive significance of p53 for a specific therapy of breast cancer.