Prognostic significance of p53, bcl-2 and EGFR in carcinoma of the endometrium

OBJECTIVE: To evaluate the part played by several parameters in the prognosis of patients with endometrial carcinoma. STUDY DESIGN: Eighty imprint smears from fresh endometrial tumor specimens were studied immunocytochemically for the expression of p53, bcl-2 and epidermal growth factor receptor. Also, the presence of estrogen receptor (ER) and progesterone receptor (PR) in the tumor tissue was measured. The data obtained were related to survival, and associations were sought between the parameters studied. RESULTS: Strong associations were found between advanced stage, high grade, lymph node metastases at diagnosis, nonendometrioid histology and p53 expression with poor survival. Bcl-2 expression was associated with good five-year survival. ER expression was associated marginally with good five-year survival, but PR expression was not. A strong association was found between p53 and advanced disease, stage and lymph node metastases at diagnosis. An association between EGFR positivity and survival was not found. CONCLUSION: p53 Expression of uterine tumors is an independent and strong indicator of poor prognosis. Even patients with stage I and II disease at surgery who have p53-positive tumors must be considered at high risk.     

REVIEW: p53 and CD44 as clinical markers of tumour progression in colorectal carcinogenesis

Recent advances in molecular genetics have importantly improved our understanding of the development of colorectal cancer. The present review gives an overview of the clinical value of the tumour-suppress or gene, p53, and the CD44 cell adhesion molecule in colorectal cancer and the pitfalls encountered in the immunohistochemical detection of these proteins. Immunohistochemistry potentially forms a procedure applicable for routine diagnosis and prognostication. Therefore, p53 expression and the independent prognostic importance of CD44v6 expression is given particular emphasis, and other molecular events underlying colorectal carcinogenesis are only mentioned briefly     

CD44 expression in colorectal cancer. An immunohistochemical study including correlation with cathepsin D immunoreactivity and some tumour clinicopathological features

CD44 is a cell adhesion molecule involved in tumour growth and progression. This study was undertaken to evaluate the expression of CD44 standard protein in a series of 54 colorectal adenocarcinomas in correlation with cathepsin D immunoreactivity and some other clinicopathological variables. Formalin-fixed and paraffin-embedded tissues were investigated with anti-CD44 standard protein and anti-cathepsin D antibody. Immunolocalisation of CD44 protein and cathepsin D was performed using LSAB method. 13 (41.9%) out of 31 carcinomas without lymph-node metastases had positive CD44 expression, whereas only 6 (26.1%) out of 23 carcinomas with lymph-node metastases were found positive for CD44 expression. CD44 expression in carcinomas was positively correlated with tumour cells cathepsin D (p<0.01) immunostaining. statistically significant correlation was found between the expression of CD44 standard protein and the tumour site, age and sex of the patients. These results suggest that the standard-type CD44 protein lymph-node metastases, probably with cooperation of cathepsin D.     

PNAS-4 expression and its relationship to p53 in colorectal cancer

PNAS-4 is a novel pro-apoptotic protein activated during the early response to DNA damage; however, the molecular mechanisms and pathways regulating PNAS-4 expression in tumors are not well understood. We hypothesized that PNAS-4 is a p53 down-stream target gene and designed this study. We searched online for putative p53-binding sites in the entire PNAS-4 gene and did not find any corresponding information. In HCT116 colon cancer cells, after being transfected with small interfering RNA to silence p53, the expressions of PNAS-4 and other known p53 target gene (Apaf1, Bax, Fas and Dr5) were determined by real-time PCR. We found that PNAS-4 was up-regulated while Apaf1, Bax, Fas and Dr5 were down-regulated. We then examined the expression of PNAS-4 and p53 mutation in colorectal cancer patients. PNAS-4 expressed both in colorectal cancers and normal tissues, but compared with paired control, PNAS-4 was up-regulated in cancers (P = 0.018). PNAS-4 overexpression ratios were correlated to the p53 mutant status (P = 0.001). The mean PNAS-4 expression levels of p53 mutant homozygote group and heterozygote group were higher than that of p53 wild type group (P = 0.013). The expression ratios of PNAS-4 (every sample in relative to its paired normal mucosa) were different between negative lymph node metastasis (66% up-regulated, 34% down-regulated) and positive metastasis (42% up-regulated, 58% down-regulated). Taken together, these findings suggested that PNAS-4 was not a p53 target, but overexpression of PNAS-4 was correlated to p53 inactivity in colorectal cancer.     

Prognostic significance and gene expression profiles of p53 mutations in microsatellite-stable stage III colorectal adenocarcinomas

Although the prognostic value of p53 abnormalities in Stage III microsatellite stable (MSS) colorectal cancers (CRCs) is known, the gene expression profiles specific to the p53 status in the MSS background are not known. Therefore, the current investigation has focused on identification and validation of the gene expression profiles associated with p53 mutant phenotypes in MSS Stage III CRCs. Genomic DNA extracted from 135 formalin-fixed paraffin-embedded tissues, was analyzed for microsatellite instability (MSI) and p53 mutations. Further, mRNA samples extracted from five p53-mutant and five p53-wild-type MSS-CRC snap-frozen tissues were profiled for differential gene expression by Affymetrix Human Genome U133 Plus 2.0 arrays. Differentially expressed genes were further validated by the high-throughput quantitative nuclease protection assay (qNPA), and confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) and by immunohistochemistry (IHC). Survival rates were estimated by Kaplan-Meier and Cox regression analyses. A higher incidence of p53 mutations was found in MSS (58%) than in MSI (30%) phenotypes. Both univariate (log-rank, P = 0.025) and multivariate (hazard ratio, 2.52; 95% confidence interval, 1.25–5.08) analyses have demonstrated that patients with MSS-p53 mutant phenotypes had poor CRC-specific survival when compared to MSS-p53 wild-type phenotypes. Gene expression analyses identified 84 differentially expressed genes. Of 49 down-regulated genes, LPAR6, PDLIM3, and PLAT, and, of 35 up-regulated genes, TRIM29, FUT3, IQGAP3, and SLC6A8 were confirmed by qNPA, qRT-PCR, and IHC platforms. p53 mutations are associated with poor survival of patients with Stage III MSS CRCs and p53-mutant and wild-type phenotypes have distinct gene expression profiles that might be helpful in identifying aggressive subsets.     

Growth-inhibitory and tumor- suppressive functions of p53 depend on its repression of CD44 expression

The p53 tumor suppressor is a key mediator of cellular responses to various stresses. Here, we show that under conditions of basal physiologic and cell-culture stress, p53 inhibits expression of the CD44 cell-surface molecule via binding to a noncanonical p53-binding sequence in the CD44 promoter. This interaction enables an untransformed cell to respond to stress-induced, p53-dependent cytostatic and apoptotic signals that would otherwise be blocked by the actions of CD44. In the absence of p53 function, the resulting derepressed CD44 expression is essential for the growth and tumor-initiating ability of highly tumorigenic mammary epithelial cells. In both tumorigenic and nontumorigenic cells, CD44's expression is positively regulated by p63, a paralogue of p53. Our data indicate that CD44 is a key tumor-promoting agent in transformed tumor cells lacking p53 function. They also suggest that the derepression of CD44 resulting from inactivation of p53 can potentially aid the survival of immortalized, premalignant cells.     

结肠癌组织中CD44S和CD44V6基因蛋白的表达及意义

摘要：目的 研究CD44S和CD44V6的表达与结肠癌临床病理特征之间的关系,以明确二者在结肠癌发展和预后中的作用。方法 选取98例结肠癌组织做为实验组,采用免疫组织化学方法,检测组织中CD44S和CD44V6基因蛋白产物表达,与组织学分型、肠壁浸润深度、脉管有无浸润、淋巴结有无转移、预后等相关因素进行实验研究。结果 CD44S和CD44V6的表达与结肠癌组织类型无关,与癌组织浸润肠壁深度、脉管浸润、淋巴结转移、远处转移等密切相关。结论 CD44S和CD44V6异常表达可能参与了结肠癌的发展并可能影响患者的预后。     

Prognostic value of somatostatin receptor subtype 2 expression in colorectal cancer

The clinical relevance of the somatostatin receptor subtype 2 (sst2) is well defined in neuroendocrine tumors but it is still a matter of debate whether its expression may have a role also in other tumors not arising from the neuroectoderm. We investigated the prognostic value of the expression levels of sst2 mRNA in a consistent group of patients affected by colorectal cancer. Survival analysis of cancer-related death showed that patients with a high sst2 mRNA expression had an unfavourable outcome (p=0.037) and a significantly shorter disease-free survival (p=0.008). Surprisingly, our findings suggest that sst2 gene overexpression is a feature of colorectal tumors that have a negative outlook; in addition, it may allow additional insight into conventional therapeutic approaches for more aggressive tumors, whose prognosis needs to be improved.     

Emerging role of p53, bcl-2 and telomerase activity in Egyptian breast cancer patients

Apoptotic cell death represents an important mechanism for the precise regulation of cell numbers, and a defense mechanism against tumor cells. Both bcl-2 and mutant p53 gene products have been involved in apoptotic pathways. On the other hand, cell proliferation capacity and tumorgenesis have been controlled by telomerase. The purpose of our study is to assess the prognostic significance of additional markers implicated in apoptosis and tumorgenesis. Fifty-one fresh tissue samples of primary breast carcinoma and 26 tissue samples of benign breast lesions were included in this study. Expression of bcl-2 in cell lysates and mutant p53 protein in nuclear fraction were measured by Oncogene Science EIA procedures. Telomerase activity was analyzed using the Telomerase-PCR-ELISA based on the TRAP (telomerase repeat amplification protocol) method. On the same specimens, steroid hormone receptors (ER and PgR) were measured in cytosol fraction using Abbott EIA assays. In addition, information regarding surgical-pathological features of the tumor was obtained. Univariate and Multivariate analysis was done to identify variables predictive of poor prognosis. Significant expression of bcl-2, mutant p53 proteins and relative telomerase activity were observed in malignant cases when compared to benign ones. Univariate analysis revealed significant association in the level of both mutant p53 and relative telomerase activity with tumor size and disease recurrence. Moreover, telomerase activity was significantly expressed in late stages than early ones. Multivariate analysis revealed that bcl-2, mutant p53, telomerase activity, PgR and age were independent prognostic factors. Among a panel of molecular genetic factors investigated, mutant p53 and relative telomerase activity were strongly associated with disease recurrence; hence they exert a significant prognostic role in breast cancer.     

Expression of p53, p21/waf, bcl-2, bax, Rb and Ki67 proteins in colorectal adenocarcinomas

This study investigated the combined immunoexpression of p53, p21, bcl-2, bax, Rb and Ki67 proteins in colorectal adenocarcinomas and correlated expression patterns with tumour stage and grade. Paraffin sections from 98 cases of colorectal adenocarcinomas were stained by immunohistochemistry for p53, p21, bcl-2, bax, Rb and MIB-1 (Ki67) proteins. In addition, 12 cases of colorectal adenomas and normal colorectal mucosa were studied in parallel. P53, p21, bcl-2, bax, Rb and Ki67 proteins were detected in at least 5% of tumour cells in 63/98, 72/98, 52/98, 96/98 and 98/98 adenocarcinomas, respectively. Comparative study of the normal-adenoma-carcinoma tissues revealed abrogation of the normal immunotopography in adenomas and adenocarcinomas, and considerable modifications, increase or reduction, of the expression of p53, p21, bcl-2, bax, Rb and Ki67 proteins in adenocarcinomas when compared with normal mucosa and adenomas. Statistically significant correlations were found between low bax expression and Dukes C stage of carcinomas, Ki67 expression and carcinoma grade, and Ki67 and Rb expression. P53, p21, bcl-2 and Rb immunoexpression did not correlate with tumour stage or grade. Our findings show that low bax immunoexpression is frequently related to colorectal adenocarcinomas with lymph node metastases suggesting that low levels of bax expression play a role in late stage colorectal cancer. The correlation between Ki67 and Rb expression, in view of previous data that the hyperphosphorylated inactive Rb protein is frequently increased in colorectal adenocarcinomas, suggests that Rb protein is somewhat ineffective in inhibiting the cell-cycle progression in these malignancies. Furthermore, our findings provide immunohistochemical evidence that the abrogation of the normal immunotopography and the modifications of the expression of p53, p21, bcl-2, bax, Rb and Ki67 proteins reflect important events in colorectal oncogenesis.     

Prognostic value of apoptosis in breast cancer (pT1-pT2). A TUNEL, p53, bcl-2, bag-1 and Bax immunohistochemical study

Apoptosis or programmed cell death produces cells breaking into several fragments of nuclei, cytoplasm or both nuclei and cytoplasm, known as apoptotic bodies which can be visualized in haematoxylin-eosin staining. Some genes (promoters and suppressors) control this process and certain mutations may induce the expression of abnormal proteins, which can be detected by immunohistochemical staining. Apoptosis can be detected by the TUNEL method either identifying apoptotic bodies or cells at the initial stages of the fragmentation process. We have studied 186 cases of infiltrating ductal breast carcinoma, stages pT1-pT2, and analysed the prognostic significance of tumour recurrence and overall survival of apoptotic index (AI) through univariate and multivariate analysis. We have also studied the immunohistochemical protein expression of apoptosis promoter and suppressors gene (p53, nuclear expression; bcl-2 and Bax, cytoplasm expression; BAG-1, nuclear and cytoplasm expression). The results indicate prognostic significance of p53 and bcl-2 related to patient death and bcl-2 and tumour size to tumour recurrence, bcl-2 acting as a protector factor (apoptotic suppressor) in both situations. On the other hand, we have not found useful prognostic information of AI either to tumour recurrence or overall survival in univariate or multivariate studies. In this study, Bax expression does not provide a new prognostic role in breast carcinoma, although it contrasts to the bcl-2 action and accelerates death.     

Expression of p27Kip1 and bcl-2, cigarette smoking,and colorectal cancer risk

Although a positive association between cigarette smoking and colorectal adenoma development is consistently found, the association with colorectal cancer remains controversial. We evaluated the potential roles of p27^Kip1 and bcl-2 protein expressions in conjunction with cigarette smoking exposure and colorectal cancer risk in a hospital-based case-control study. A total of 163 colorectal cancer patients from Roswell Park Cancer Institute and Buffalo General Hospital and 326 healthy controls responded to a standardized questionnaire on colorectal cancer risk factors including detailed information on their history of cigarette smoking; 110 of the patients' tumours were available for immunohistochemical analysis of p27^Kip1 and bcl-2 protein overexpression. An avidin-biotin immunoperoxidase procedure was used to determine expression after incubation with mouse monoclonal p27^Kip1 and mouse monoclonal bcl-2 antibodies, respectively. A statistically significant trend for total pack-years of smoking was found when p27^Kip1 positive cases were compared with p27^Kip1 negative cases (trend test, p = 0.007). Although a weak inverse association was observed with smoking exposure among p27^Kip1 negative tumour cases in comparison to controls, a significant dose-response association was seen with p27^Kip1 positive tumours. The relative risk of developing a p27^Kip1 positive tumour was estimated to be 1.17 (95% CI 0.54-2.54) for those with less than 20 pack-years, 1.95 (95 % CI 0.95-3.97) for those with 20-39 pack-years, and 2.25 (95% CI 1.14-4.45) for those with greater than 39 pack-years of smoking exposure (trend test, p = 0.009) when compared with controls. When cases with bcl-2 expression were compared with cases without bcl-2 expression, suggestion of a trend was also observed with pack-years smoked (trend test, p = 0.09). In our study of 110 patients with sporadic colorectal cancer and 326 controls, we observed differences in associations between cigarette smoking and expressions in p27^Kip1 and bcl-2. Our data suggest that bcl-2 overexpression (or a bcl-2 dependent pathway) is associated with cigarette smoking in the development of colorectal cancer, whereas a loss of p27^Kip1 expression is not. These associations indicate that there is aetiological heterogeneity in colorectal cancer development, and that they can indirectly allude to where these changes in protein expression occur in the adenoma-carcinoma sequence (i.e. early versus late events).     

Study of P53 protein expression in colorectal cancer

Mutations of the P53 gene, strictly associated with the carcinogenesis are a commonly observed in neoplastic cells. The aim of this study was the immunohistochemical evaluation of P53 protein expression in colorectal carcinomas and analysis of its relationship to chosen anatomo-clinical and morphological parameters of the tumours. The study used the material obtained during surgical treatment of 74 colorectal carcinomas. Tissue sections were fixed in 10% buffered formaldehyde solution, embedded in paraffin and stained immunohistochemically with the antihuman P53 protein monoclonal antibody. The immunolocalization of P53 protein was performed using the Labelled Streptavidin Biotin (LSAB) method. The P53 protein expression was semiquantitatively assessed in neoplastic cells and the reaction present in more than 25% of tumour cells was accepted as the threshold of positivity. No correlation was found between P53 protein expression and tumour histologic type and site, and age and sex of patients. However, P53 protein expression in primary and metastatic tumours was found statistically significantly correlated.     

Expression of p27Kip1 and bcl-2, cigarette smoking, and colorectal cancer risk

Although a positive association between cigarette smoking and colorectal adenoma development is consistently found, the association with colorectal cancer remains controversial. We evaluated the potential roles of p27^Kip1 and bcl-2 protein expressions in conjunction with cigarette smoking exposure and colorectal cancer risk in a hospital-based case-control study. A total of 163 colorectal cancer patients from Roswell Park Cancer Institute and Buffalo General Hospital and 326 healthy controls responded to a standardized questionnaire on colorectal cancer risk factors including detailed information on their history of cigarette smoking; 110 of the patientsfitumours were available for immunohistochemical analysis of p27^Kip1 and bcl-2 protein overexpression. An avidin?biotin immunoperoxidase procedure was used to determine expression after incubation with mouse monoclonal p27^Kip1 and mouse monoclonal bcl-2 antibodies, respectively. A statistically significant trend for total pack-years of smoking was found when p27^Kip1 positive cases were compared with p27^Kip1 negative cases (trend test, p = 0.007). Although a weak inverse association was observed with smoking exposure among p27^Kip1 negative tumour cases in comparison to controls, a significant dose?response association was seen with p27^Kip1 positive tumours. The relative risk of developing a p27^Kip1 positive tumour was estimated to be 1.17 (95% CI 0.54?2.54) for those with less than 20 pack-years, 1.95 (95 % CI 0.95?3.97) for those with 20?39 pack-years, and 2.25 (95% CI 1.14?4.45) for those with greater than 39 pack-years of smoking exposure (trend test, p = 0.009) when compared with controls. When cases with bcl-2 expression were compared with cases without bcl-2 expression, suggestion of a trend was also observed with pack-years smoked (trend test, p = 0.09). In our study of 110 patients with sporadic colorectal cancer and 326 controls, we observed differences in associations between cigarette smoking and expressions in p27^Kip1 and bcl-2. Our data suggest that bcl-2 overexpression (or a bcl-2 dependent pathway) is associated with cigarette smoking in the development of colorectal cancer, whereas a loss of p27^Kip1 expression is not. These associations indicate that there is aetiological heterogeneity in colorectal cancer development, and that they can indirectly allude to where these changes in protein expression occur in the adenoma?carcinoma sequence (i.e. early versus late events).     

大肠癌组织及癌旁组织中c-myc,COX-2和CD44v6基因表达量差异的检测

目的:通过检测大肠癌组织和癌旁组织中c-myc,COX-2以及CD44v6的表达水平,探讨这三种基因在大肠癌发生和发展中的意义。方法:应用实时荧光定量PCR技术检测了10例大肠癌组织和相应癌旁组织中c-myc,COX-2以及CD44v6基因表达水平的差异,并探讨了各基因在癌组织中的表达水平与大肠癌临床病理指标之间的关系。结果:c-myc,COX-2以及CD44v6在大肠癌组织和癌旁组织中的表达均有非常显著性差异(P<0.01);癌组织中COX-2和CD44v6的表达与淋巴结转移、分化程度及Dukes分期有关(P<0.05)。结论:c-myc,COX-2和CD44v6的异常表达均与大肠癌密切相关,三者从不同方面对大肠癌的发生和发展起到了重要作用,可作为早期诊断和预后的参考指标。     

大肠癌组织及癌旁组织中c—myc，COX-2和CD44v6基因表达量差异的检测

目的：通过检测大肠癌组织和癌旁组织中c-myc,COX-2以及CD44v6的表达水平,探讨这三种基因在大肠癌发生和发展中的意义。方法：应用实时荧光定量PCR技术检测了10例大肠癌组织和相应癌旁组织中c-myc,COX-2以及CD44v6基因表达水平的差异,并探讨了各基因在癌纽织中的表达水平与大肠癌临床病理指标之间的关系。结果：c-myc,COX-2以及CD44v6在大肠癌组织和癌旁组织中的表达均有非常显著性差异（P〈0．01）;癌组织中COX-2和CD44v6的表达与淋巴结转移、分化程度及Dukes分期有关（P〈0．05）。结论：c—myc,COX-2和CD44v6的异常表达均与大肠癌密切相关,三者从不同方面对大肠癌的发生和发展起到了重要作用,可作为早期诊断和预后的参考指标。