Prognostic value of DNA index, S-phase fraction and p53 protein accumulation after surgical resection of esophageal squamous-cell carcinomas in Thailand

Prognostic significance of p53 expression in patients with esophageal cancer: a meta-analysis

Background

The prognostic value of p53 protein expression in esophageal cancer has been evaluated, but the results remain inconclusive and no consensus has yet been achieved. This meta-analysis was conducted to quantitatively assess the prognostic significance of p53 expression in esophageal cancer.

Methods

Publications that assessed the clinical or prognostic significance of p53 expression in esophageal cancer and were published before July 1, 2015 were identified by searching the PubMed and EMBASE databases. A meta-analysis was performed to clarify the association between p53 expression and the clinical outcomes.

Results

A total of 36 publications met the criteria and included 4577 cases. Analysis of these data showed that p53 expression in esophageal cancer was significantly associated with poorer 5-year survival (RR = 1.30, 95 % CI: 1.11–1.51, P = 0.0008). Subgroup analyses according to histological type, continent of the patients, and cut-off value revealed the similar results. The results also indicated that p53 expression was highly associated with advanced TNM stages (I/II vs. III/IV, OR = 0.74, 95 % CI: 0.55–0.99, P = 0.04), lymph node metastasis (OR = 0.77, 95 % CI: 0.66–0.90, P = 0.001), and distant metastasis (OR = 0.46, 95 % CI: 0.26–0.80, P = 0.006). However, p53 expression in the included studies was not significantly associated with tumor size (≤ 5 cm vs. > 5 cm, OR = 1.13, 95 % CI: 0.92–1.40, P = 0.24), tumor location (upper + middle vs. lower, OR = 0.91, 95 % CI: 0.70–1.17, P = 0.45), grade of differentiation (well + moderate vs. poor, OR = 1.10, 95 % CI: 0.90–1.34, P = 0.35), and the depth of invasion (T1/T2 vs. T3/T4, OR = 0.86, 95 % CI: 0.71–1.03, P = 0.09).

Conclusions

This meta-analysis showed that p53 expression may be a useful biomarker for predicting poorer prognosis in patients with esophageal cancer.

Systematic review and meta-analysis of tumor biomarkers in predicting prognosis in esophageal cancer

BACKGROUND

Esophageal cancer (EC) is a frequently occurring cancer with poor prognosis despite combined therapeutic strategies. Many biomarkers have been proposed as predictors of adverse events. We sought to assess the prognostic value of biomarkers in predicting the overall survival of esophageal cancer and to help guide personalized cancer treatment to give patients the best chance at remission.

METHODS

We conducted a systematic review and meta-analysis of the published literature to summarize evidence for the discriminatory ability of prognostic biomarkers for esophageal cancer. Relevant literature was identified using the PubMed database on April 11, 2012, and conformed to the REMARK criteria. The primary endpoint was overall survival and data were synthesized with hazard ratios (HRs).

RESULTS

We included 109 studies, exploring 13 different biomarkers, which were subjected to quantitative meta-analysis. Promising markers that emerged for the prediction of overall survival in esophageal squamous cell cancer included VEGF (18 eligible studies, n=1476, HR=1.85, 95% CI, 1.55-2.21), cyclin D1 (12 eligible studies, n=1476, HR=1.82, 95% CI, 1.50-2.20), Ki-67 (3 eligible studies, n=308, HR=1.11, 95% CI, 0.70-1.78) and squamous cell carcinoma antigen (5 eligible studies, n=700, HR=1.28, 95% CI, 0.97-1.69); prognostic markers for esophageal adenocarcinoma included COX-2 (2 eligible studies, n=235, HR=3.06, 95% CI, 2.01-4.65) and HER-2 (3 eligible studies, n=291, HR=2.15, 95% CI, 1.39-3.33); prognostic markers for uncategorized ECs included p21 (9 eligible studies, n=858, HR=1.27, 95% CI, 0.75-2.16), p53 (31 eligible studies, n=2851, HR=1.34, 95% CI, 1.21-1.48), CRP (8 eligible studies, n=1382, HR=2.65, 95% CI, 1.64-4.27) and hemoglobin (5 eligible studies, n=544, HR=0.91, 95% CI, 0.83-1.00).

CONCLUSIONS

Although some modest bias cannot be excluded, this review supports the involvement of biomarkers to be associated with EC overall survival.

p53 immunohistochemical expression and patient prognosis in esophageal squamous cell carcinoma

It is generally accepted that overexpression of p53 protein is associated with poor prognosis in gastric, lung, and other types of cancer. However, the prognostic significance of p53 aberrations in esophageal cancer remains unclear. This is the largest study (n = 266) examining clinical and prognostic features of p53 immunohistochemical expression in esophageal squamous cell carcinoma. In 139 (52%) esophageal tumors, nuclear immunoreactivity for p53 protein was detected. p53 aberrant expression was not associated with sex, age, preoperative treatment, TNM stage, or histological grade. Furthermore, p53 expression did not correlate with disease-free survival (P = 0.73) or overall survival (P = 0.62). In addition, no significant modification effect by any of the covariates in the survival analysis was observed (all P > 0.15). In conclusion, our large-scale study demonstrates that p53 expression has no impact on the prognosis of esophageal squamous cell carcinoma.

Biological behavior of mucoepidermoid carcinoma of the esophagus

Mucoepidermoid carcinoma of the esophagus (MEC) is uncommon and has not been fully investigated. The biological behavior and clinical aspects of MEC were studied. The clinical features of eight patients with MEC were compared with 51 cases of squamous cell carcinoma of the esophagus (SCC). Proliferating cell nuclear antigen (PCNA), p53, and carcinoembryonic antigen (CEA) were stained in the resected specimens by immunohistochemistry. Seven out of 8 cases (87.5%) had stage III by TNM classification. Four cases died of widespread metastases and 2 cases died of local recurrence within 2 years after the surgery. Neither chemotherapy and radiotherapy were effective against MEC. Overall median survival periods were 10.8 months for MEC and 32.1 months for SCC (P<0.05). When patients in stage III alone were compared, MEC tended to have a worse prognosis than SCC (P=0.058). Immunohistochemical studies revealed that the positive rates of PCNA and CEA were significantly higher in MEC than in SCC (P<0.05), while there was no significant difference in p53 positive rate. Esophageal MEC had an aggressive biological nature and was resistant to adjuvant therapies. The poor prognosis of esophageal MEC may be caused by high proliferative and metastatic potential.

Role of molecular biology in the follow-up of patients who have Barrett's esophagus

At present, the follow-up of patients who have Barrett's esophagus (BE) should occur within the setting of an endoscopic biopsy surveillance program and with the frequency of surveillance as proposed by the American College of Gastroenterology. In the future, patients who have BE will be further stratified according to their risk for progression to invasive carcinoma. This stratification will permit the development of more rational surveillance programs. Models that incorporate epidemiologic risk factors, reflux symptoms, and endoscopic and histologic findings will likely include panels of biomarkers for further stratification of patients as low, intermediate, or high risk. Therefore, the challenge over the next decade will be to define the role of molecular markers in endoscopic surveillance strategies and to identify additional clinically relevant molecular markers for prognosis as intermediate markers for chemoprevention and as molecular targets for novel gene therapies.

TP53 mutations and MDM2 gene amplification in squamous-cell carcinomas of the esophagus in south Thailand

Squamous-cell carcinoma of the esophagus (SCCE) shows geographic variations in incidence that are thought to reflect the etiological involvement of environmental or dietary risk factors. Mutations of TP53 are frequent in SCCE, and there is evidence that both the frequency and type of these mutations may differ from one geographic area to the other. Although SCCE is relatively rare in most parts of Thailand, the province of Songkhla (south Thailand) has been described as a high-risk area for SCCE. We have analyzed 56 SCCE cases from this area for TP53 mutations by denaturing gradient gel electrophoresis (DGGE, exons 5-8) and direct DNA sequencing. The same tumors were also analyzed for MDM2 gene amplification by differential PCR. TP53 mutations were detected in 23 cases (41%). In contrast, clear amplification of MDM2 was detected in only 2 cases (4%), both of which contained wild-type TP53. Comparison with published results from other geographic areas of high SCCE incidence revealed that the spectrum of TP53 mutations in south Thailand is similar to that observed in central China (Henan Province) but clearly differs from that of SCCE from western Europe (Normandy, France; northern Italy), with more G:T transversions and fewer mutations affecting A and T base pairs. These results suggest that SCCE from south Thailand and from central China may involve similar risk factors.

Detection of circulating anti-p53 antibodies in esophageal cancer patients

It has been reported that circulating anti-p53 antibodies (p53-Ab) in the serum are detected in some cancers. To investigate the usefulness of detecting p53-Ab, we measured the circulating p53-Ab in comparison with squamous cell carcinoma antigen (SCC-Ag) in patients with esophageal carcinoma. Serum specimens from 46 esophageal cancer patients (42 squamous cell carcinomas, 3 mucoepidermoid carcinomas and 1 basaloid squamous carcinoma) and 13 healthy subjects were studied. Serum p53-Ab was measured by an enzyme-linked immunosorbent assay. Surgically resected specimens from 43 patients were immunohistochemically stained for p53. Serum SCC-Ag was measured by a radioimmunoassay. The results were analyzed with the clinical data and outcome. Serum p53-Ab was detected in 13 (28%) of the 46 patients, but not in any of the healthy subjects. The positive rate was 0% (0/6) in stage I, 60% (3/5) in stage IIA, 30% (3/10) in stage IIB, 29% (7/24) in stage III and 0% (0/1) in stage IV. There was no difference in the outcome between the p53-Ab-positive and p53-Ab-negative patients. Immunohistochemically, 30 (70%) of the 43 specimens stained positively for p53. Serum p53-Ab was detected in 43% (13/30) of the patients with tumors which stained positively for p53. There was a close correlation between positivity for p53 immunostaining and positivity for p53-Ab (p<0.01). An elevated level of SCC-Ag was found in only 13%of the patients, and most patients positive for SCC-Ag already had advanced disease with lymph node metastasis and invasion to the adventitia. In conclusion, serum p53-Ab was detected in Japanese esophageal cancer patients at a frequency similar to that reported in Western countries. Serum p53-Ab may be a potentially useful molecular marker for detection and screening of esophageal cancer. Further studies of a large population may be required to elucidate the true diagnostic usefulness of measuring the serum p53-Ab.

Biological evaluation of undifferentiated carcinoma of the esophagus

BACKGROUND

Patients with undifferentiated carcinoma of the esophagus (UEC) are rare and have a poor prognosis compared with those with differentiated squamous cell carcinomas (DECs). We compared clinicopathological and biological features of UEC and DEC, with emphasis on markers for epithelial cell origin, proliferation, and cell-cell adhesion.

METHODS

Seven patients with UEC were compared with 21 with DEC. Immunohistochemical studies were performed by using monoclonal antibodies to cytokeratin, epithelial membrane antigen, p53, p21WAF1/CIP1, Ki-67, E-cadherin, desmoglein-1, and thrombomodulin.

RESULTS

Patients with UEC had a poorer prognosis because of hematogenous metastasis at the time of presentation (mean survival, 6.5 +/- 6.2 vs. 35.5 +/- 28.9 months; P < .05). Immunohistochemical findings for cytokeratin and epithelial membrane antigen suggest that some UECs had epithelial origins. The following immunohistochemical profile of UEC was consistent with its highly malignant properties: (1) reduced or negative expression of cell-cell adhesion molecules such as E-cadherin, desmoglein-1, and thrombomodulin, (2) high positive rate for p53 and Ki-67, and (3) negative expression of p21WAF1/CIP1.

CONCLUSIONS

The immunohistochemical findings for UEC showed its high cell-proliferative activity and a high potential for metastasis. Clinical features of UEC were supported by the results of immunohistochemical findings.

The clinicopathological significance of p21 and p53 expression in esophageal squamous cell carcinoma: an analysis of 153 patients

OBJECTIVE

The p21 gene is thought to play a central role in tumor suppression. The aim of this study was to examine the clinicopathological role of p21 and p53 in esophageal squamous cell carcinomas.

METHODS

The expression of p21 and p53 proteins in 153 Chinese patients (131 men, 22 women) with resected esophageal squamous cell carcinomas was investigated by the immunohistochemical method. Correlation between p21 and p53 expression and clinicopathological features was examined.

RESULTS

The expression of p21 and p53 was detected in 70% and 64% of the tumors, respectively. The staining of p21 and p53 was also found in squamous carcinoma in situ, dysplasia, and nontumor epithelium. p21 expression was often weak in the suprabasal cells and found in better differentiated tumors. There was no significant correlation between the expression of p21 and the abnormal accumulation of p53. The prognosis of the patients depended on the size, stage, and p21 expression of the lesion. In stage III lesions with tumor diameter < or = 7.5 cm (n = 93), patients with loss of p21 expression had better survival. The survival rates of patients were worse if they had expression of both p21 and p53.

CONCLUSIONS

Thus, p21 and p53 had prognostic value for esophageal squamous cell carcinomas. Loss of p21 expression was shown without p53 alternations, indicating that other mechanisms are also involved in turning off the gene. The pattern of p21 and p53 expression predicts an aggressive clinical course of esophageal squamous cell carcinomas.

Prognosis of esophageal squamous cell carcinoma: analysis of clinicopathological and biological factors

OBJECTIVE

Esophageal squamous cell carcinoma (ESCC) is rather common among the Chinese, but the therapeutic outcome is dismal. Knowledge of the prognostic factors in cancerous patients may influence therapeutic strategy. However, systemic analyses of clinicopathological and biological factors for patients with ESCC are few, and the results are controversial.

METHODS

Between 1985 and 1996, 117 patients undergoing en bloc esophagectomy and gastric substitution were enrolled. None had neoadjuvant treatment. Postoperative adjuvant therapy was provided for patients at and beyond stages IIa. Clinical responses were followed routinely. Flow cytometry was used to measure DNA ploidy and synthesis-phase fraction (SPF) of the resected esophageal tissues from all patients. Immunohistochemistry was also used to examine the expression of proliferating cell nuclear antigen (PCNA), epidermoid growth factor receptor (EGFR), HER-2/neu, and p53 in the pathological sections. Clinical correlation was evaluated by chi2 with Fisher's exact test, and survival by log-rank test.

RESULTS

The overall survival rates were 74% for 1 yr, 48% for 3 yr, and 38% for 5 yr. TNM tumor staging, the number of diseased lymph nodes (N < or = 3 or N > 3), degree of cell differentiation, DNA ploidy, SPF, and lymphovascular invasion were more useful than biological markers, such as PCNA, EGFR, HER-2/neu, and p53, for the prognosis of ESCC. Multivariate analysis revealed significant correlation of tumor staging and number of diseased lymph nodes with patient survival after surgery.

CONCLUSIONS

En bloc esophagectomy may provide a rather satisfactory survival rate for patients with early stage ESCC. However, for patients with distant lymph node metastasis and those with more than three lymph nodes involved, radical surgical resection, even combined with postoperative chemoradiotherapy, cannot improve survival. The prognostic value of biological markers, including PCNA, EGFR, HER-2/neu, and p53, however, is limited.

p21Waf1/Cip1 expression is a prognostic marker in curatively resected esophageal squamous cell carcinoma, but not p27Kip1, p53, or Rb

BACKGROUND

p21Waf1/Cip1 (p21), p27Kip1 (p27), p53, and Rb play critical roles in cell cycle regulation and may influence the clinical behavior of tumors. We examined whether their expression is useful to predict survival of patients with esophageal squamous cell carcinoma (ESC).

METHODS

Expression of p21, p27, p53, and Rb was studied by the immunohistochemical method in specimens from 62 patients with curatively resected ESC tumors and scored by a computerized image analysis system.

RESULTS

The median expression scores of p21, p27, p53, and Rb (14, 12, 27, and 50, respectively) were used as cut-off points to define low and high expression groups for each protein. The 5-year survival rate for the high p21 expression group was 68%; that for the low expression group was 31% (P = .0062). p27, p53, and Rb were not correlated with overall survival. When patients were categorized into four groups based on p21 expression level and lymph node involvement (pN), the survival curves were significantly different (P = .0017). Thus, patients without lymph node involvement but with low p21 expression had survival similar to that of patients with lymph node involvement and high p21 expression. Multivariate analysis showed that age (P = .0102), lymph node involvement (P = .0076), and p21 (P = .0276) were independent prognostic factors.

CONCLUSIONS

Expression of p21 is an independent prognostic factor in curatively resected ESC. Definition of new subgroups of patients based on p21 expression may help to enhance the stratification of stage.

p150 expression and its prognostic value in squamous-cell carcinoma of the esophagus

To investigate p150, a recently cloned protein, and its prognostic value in esophageal squamous-cell carcinoma, 100 samples were analyzed immunohistochemically and 30 fresh samples by the immunoblot method. All 100 patients, from Northern China, over-expressed p150 as compared with controls in the immunohistochemical study, and the same was found for the tumors of the 30 patients analyzed by Western-blot analysis. A close correlation could be observed between p150 over-expression and the state of differentiation, since well-differentiated cancers showed high p150 expression, and vice-versa (p < 0.0001). In addition, patients with high p150 expression had significantly fewer tumor metastases (local or distant, p < 0.005). Furthermore, and prognostically more relevant, survival analysis showed that patients with high p150 expression had significantly better overall survival (p < 0.0026). This somehow unexpected result may, however, be typical for squamous carcinoma, since in human cervical carcinoma, another squamous carcinoma, the p150 values were reported to rise early in all tumors, to stay high in patients with longer survival as well. In addition, patients with regional lymph-node metastasis and high p150 expression survived longer than those with regional lymph-node metastasis and lower p150 expression (p < 0.0066). Multivariate analysis showed that p150 is an independent factor for predicting patient survival. The results suggest that p150 may be a new biomarker for squamous-cell carcinoma of the esophagus, with specific prognostic value.

Radiotherapy for oesophagus carcinoma: the impact of p53 on treatment outcome

BACKGROUND AND PURPOSE

Wildtype p53 protein plays an important role in the cellular response to ionizing radiation and other DNA damaging agents and is mutated in many human tumours. We evaluated the relationship of the immunohistochemically determined p53 protein status and the disease control with radiotherapy alone for carcinoma of the oesophagus.

MATERIALS AND METHODS

Immunostaining for p53 protein was performed on paraffin-embedded specimens from 69 patients with adeno- and squamous cell carcinoma of the oesophagus. All patients were treated by radiotherapy exclusively, consisting of a combination of external irradiation and intraluminal brachytherapy, using two different dose levels.

RESULTS

Fifty-four percent (37/69) of the tumours showed overexpression of the p53 protein. No difference in pre-treatment parameters for p53-positive and p53-negative cases was detected. In multivariate analysis p53 was significantly associated with overall survival (OS) next to weight loss, tumour stage and N-stage. For metastatic-free survival (MFS) p53 status proved to be the sole independent prognostic factor. The influence of p53 on local recurrence-free survival (LRFS), however, was not as strong as on OS and MFS.

CONCLUSIONS

Immunohistochemically detected overexpression of mutated p53 protein in oesophagus carcinoma was an independent prognostic factor in a group of patients treated with radiotherapy alone.

Analysis of DNA ploidy and expression of tumour-associated antigens on human oral carcinomas xenografted in nude mice

Human squamous cell carcinomas (SCC) of the oral cavity were successfully established as xenografts in nude mice. Tumours with higher malignancy scores and involvement of lymph nodes in patients were more readily accepted as xenografts in nude mice. The xenografted tumours were characterised with respect to morphology, histology, DNA index and expression of tumour-associated antigens (TAA). Flow cytometric analysis of cellular DNA content revealed that many of the xenografts retained the parent tumour DNA pattern while some of the xenografts showed progression to aneuploidy. All the xenografted tumours expressed TAA recognised by monoclonal antibody (MAb) 3F8E3. On Western blotting, MAb 3F8E3 recognised proteins of molecular weight 62-64 kDa on parent and xenografted tumours. In general, the xenografts reflect many of the characteristics of the tumours from which they were derived and may provide a useful model for investigating newer approaches of treatment and diagnosis.

Prevalence and predictive value of p53 mutation in patients with oesophageal squamous cell carcinomas: a prospective clinico-pathological study and survival analysis of 70 patients

The tissues from 70 Chinese patients with oesophageal squamous cell carcinoma were prospectively collected to study for the pattern of p53 mutations and its relationship with clinico-pathological features and prognosis using immunohistochemistry, polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis and DNA sequencing. p53 over-expression and p53 mutations were detected in 73% and 44% of the patients. These p53 aberrations had no relationship with the patient age, sex, smoking/drinking habits and tumor site, size or stage. The p53 over-expression was more intense in moderately/poorly-differentiated squamous cell carcinomas. Thirty-three p53 mutations were noted in 31 patients; 18.2% in exon 5, 15.2% in exon 6, 33.3% in exon 7 and 33.3% in exon 8. Mutations were primarily point mutations and common in codons 248, 273 and 285. There were 46% transversions, 36% transitions and 18% frameshift. The survival of the patients depended mainly on the extent of resection. In patients with stage III oesophageal cancer, the median survival of those with p53 mutations was 6.8 months whereas those without was 12.5 months. The results were of clinical importance although the value did not reach statistical significance. Thus, there was a definite role of p53 mutations in the pathogenesis of oesophageal squamous cell carcinomas. p53 mutations were not synonymous with p53 over-expression. The distribution of p53 mutations in oesophageal cancers suggested that the etiologic contribution might be complex and probably involve different exogenous and endogenous exposures. p53 mutations also appear to play a role in predicting the survival of patients with stage III oesophageal squamous cell carcinomas.