Combined examination of p27(Kip1), p21(Waf1/Cip1) and p53 expression allows precise estimation of prognosis in patients with gastric carcinoma

Clinicopathological profile and its association with peritoneal disease among gastric cancer patients

BACKGROUND

There are no clinicopathological criteria or test to predict peritoneal metastasis either in primary or recurrent gastric cancer. The early prediction will help in altering or adding other adjuvant potential therapy modalities like HIPEC and maintenance chemotherapy.

METHODS

Paraffin based blocks of 110 gastric tumor specimens were subjected to IHC staining to assess VEGF, Her 2 neu, E cadherin, bcl 2 and p 53 expression and its association with peritoneal disease evaluated.

RESULTS

Her 2 neu uptake was present in 17.3%, bcl-2 expression in 19.1%, P53 expression in 40.9%, VEGF in 41.8% and E cadherin expression in 49.1% patients. On univariate analysis, a younger age(p = .029), female sex(p = .026), positive VEGF expression (p = .001) and p53 expression(p = .015) were significantly associated with peritoneal disease. A binomial logistic regression was performed to ascertain the effects of independent variables evaluated on univariate analysis. Of the 10 predictors variables, only three were statistically significant: tumor type, P53, and VEGF. Positive VEGF expression had 48.7, E cadherin 2.6 and Her2neu 1.5 times higher odds of exhibiting peritoneal disease.

CONCLUSION

A younger age, female sex, distal 2/3rd, diffuse variant, VEGF staining in >10% cells and decrease p53 expression were associated with peritoneal disease.

Characterization of oncogene suppressor marker expression in patients with submucosal gastric carcinoma

The aim of the present study was to determine the clinical significance of p53 and p21^ras p21^wafl, p27^kip1 and p16^ink4a expression in cases of early gastric cancer. A total of 81 patients who had undergone gastrectomy with D2 lymphadenectomy between 1971 and 2004 were retrospectively investigated. The immunohistochemical expression of p21^ras, p53, p21^waf1/cip1, p27^kip1 and p16^ink4a in the tissues was evaluated. In normal, metaplastic and tumoral mucosa, p53 was positive in 53, 87.3, and 87.1% of the cases, respectively. In the same tissues, p21^ras was positivE in 85.3, 86 and 96.8%, respectively. Positivity FOR p16^ink4a was DETECTED IN 46.3, 91.1 and 86% OF THE CASES, respectively, WHEREAS p27^kip1 WAS positiVE IN 60, 94.7 and 95.3%, and p21^wafl/cip1 WAS positivE IN 32.4, 72.7 and 71.4% OF THE CASES, respectively. All THE tumors WERE positive for p53. Tumors with lymph node invasion presented WITH OVERexpression (+4) of p53 in 47% of the cases VS. 17% OF patients who DID not HAVE lymph node involvement. THEREFORE, higher expression of p53, p21^ras and p21^wafl/cip1 IN the tumor exhibited a statistically significant association with lymph node involvement.

Clinical significances of p27 in digestive tract cancers: a comprehensive analysis on immunohistochemistry staining, published literatures, microarray and RNA-seq data

In the present study, we conducted a comprehensive analysis on the clinical roles of p27 protein and p27 gene in digestive tract cancers (DTCs). First, we performed immunohistochemistry staining and found that p27 protein was down-regulated in DTCs. Then we collected 62 publications and calculated the combined hazard ratios (HRs), odds ratios (ORs) and 95% confidence intervals (95% CIs) to clarify the relationships of p27 protein expression with prognoses and clinicopathological parameters. The overall HRs indicated that the down-regulated p27 protein was an independent prognostic biomarker for overall survival (HR: 1.58, 95% CI: 1.38-1.81, P < 0.0001) but not for disease-free survival and cancer-specific survival. The combined ORs indicated that a low expression of p27 protein was positively related to lymph node metastasis (OR: 2.15, 95% CI: 1.57-2.96, P < 0.0001), distant metastasis (OR: 2.02, 95% CI: 1.12-3.63, P = 0.019) and pathology grading (OR: 2.14, 95% CI: 1.75-2.62, P < 0.0001). Additionally, 60 DTCs-related microarray and RNA-seq datasets were obtained to investigate the expression level and clinical value of p27 gene in DTCs patients. We found that the expression level of p27 gene in DTCs was similar to that in normal controls. And no significant associations of p27 gene expression with prognoses and clinicopathological factors were observed. In conclusion, according to our results, it was p27 protein, but not p27 gene, that can function as an effective biomarker to predict the clinical outcome in patients with DTCs. The down-regulation of p27 protein in DTCs may not result from the altered expression of p27 gene.

Clinicopathological features of superficial non-ampurally duodenal epithelial tumor; gastric phenotype of histology correlates to higher malignant potency

BACKGROUND

Superficial non-ampullary duodenal epithelial tumors (SNADETs) are relatively rare, but they are now being detected more frequently due to advances in endoscopic technology. Nevertheless, the pathological nature of SNADETs remains unclear and a management strategy for these tumors has not been established.

METHODS

To elucidate the clinicopathological features, we conducted a retrospective analysis of 138 endoscopically resected SNADETs. Lesions were classified into two groups by histological grade according to the Vienna classification: category 3 (71 lesions, 51.4%) and category 4/5 (67 lesions, 48.6%).

RESULTS

Compared with category 3 lesions, category 4/5 lesions were significantly more common in elderly patients (p < 0.001) and had a significantly larger tumor diameter (p = 0.001). Immunohistochemical analysis showed that category 4/5 lesions expressed MUC5AC (p = 0.002), MUC6 (p < 0.001), and p53 (p = 0.003) significantly more frequently and expressed CD10 (p = 0.002) and CDX2 (p = 0.029) significantly less frequently. Multivariate regression analysis showed that advanced age (p < 0.001), MUC6 expression (p = 0.001), and p53 expression (p = 0.004) were independent risk factors for a classification of category 4/5. In addition, advanced age (p = 0.010) and MUC5AC expression (p = 0.011) were identified as risk factors for lesions classified as category 4.2 (noninvasive carcinoma) or higher. All category 5 lesions expressed MUC5AC.

CONCLUSIONS

The gastric phenotype of MUC5AC and MUC6 may be linked to the malignant potential of SNADETs.

Molecular analysis of gastric differentiated-type intramucosal and submucosal cancers

Identification of the molecular characteristics of intramucosal (IMCs) and submucosal cancers (SMCs) is essential to our understanding of early gastric carcinogenesis. However, little is known regarding the differences between the 2 lesions. One hundred and forty-eight patients with primary early gastric cancer [IMC, 106; SMC, 42] were characterized for expression of cell cycle-related proteins and loss of heterozygosity (LOH). We also examined microsatellite instability (MSI) and methylation status. For LOH and methylation studies, we used a panel of 17 microsatellite markers (3p, 4p, 5q, 9p. 13q, 17p, 18q and 22q) and promoter regions of 9 genes (MLH-1, RUNX3, p16, HPP1, RASSF2A, SFRP1, DKK-1, ZFP64 and SALL4) that are frequently altered or methylated in gastric cancers. Overexpression of p53 and cyclin D1 was observed in SMC. In addition, low expression of p27 was more frequent in SMC than in IMC. Frequencies of 4p, 9p, 13q and 22q were significantly higher in SMC than in IMC. The SALL4 gene was frequently methylated in SMC compared with IMC. However, other gene methylations were common in both IMC and SMC. The frequency of LOH-high status/methylation-low status was significantly higher in SMC than in IMC. However, LOH-low status/methylation-high status in SMC was more frequently found in IMC. Our data confirm that methylation of cancer-related genes plays a major role in the development of IMCs. Importantly, the results also show that gastric submucosal progression is characterized by the accumulation of specific genetic alterations. In addition, changes of cell cycle-related proteins are associated with cancer progression.

Gastric adenocarcinoma and Helicobacter pylori: correlation with p53 mutation and p27 immunoexpression

INTRODUCTION

Helicobacter pylori infection is an established risk factor for gastric cancer development, but the exact underlying mechanism still remains obscure. The inactivation of tumor suppressor genes such as p53 and p27(KIP1) is a hypothesized mechanism, although there is no consensus regarding the influence of H. pylori cagA(+) in the development of these genetic alterations.

GOALS

To verify the relationship among H. pylori infection, p53 mutations and p27(Kip1) Protein (p27) expression in gastric adenocarcinomas (GA) seventy-four tissues were assayed by PCR for H. pylori and cagA presence. Mutational analysis of p53 gene was performed by single-strand conformation polymorphism (SSCP). Seventy tissues were analyzed by an immunohistochemical method for p27 expression.

RESULTS

From the samples examined, 95% (70/74) were H. pylori positive, 63% cagA(+). Altered p53 electrophoretic mobility was found in 72% of cases and significantly more frequent in the presence of cagA. Considerable reduction in p27 expression (19%) was found with a tendency for association between cagA(+) and p27(-), although the results were not statistically significant. Concomitant alterations of both suppressor genes were detected in 60% of cases. In the cases cagA(+), 66.7% of them had these concomitant alterations.

CONCLUSIONS

The data suggest that H. pylori cagA(+) contributes to p53 alteration and indicate that concomitant gene inactivation, with reduced p27 expression, may be a mechanism in which H. pylori can promote the development and progression of gastric cancer.

Analysis of cell cycle-related proteins in gastric intramucosal differentiated-type cancers based on mucin phenotypes: a novel hypothesis of early gastric carcinogenesis based on mucin phenotype

Background

Abnormalities of cell cycle regulators are common features in human cancers, and several of these factors are associated with the early development of gastric cancers. However, recent studies have shown that gastric cancer tumorigenesis was characterized by mucin expression. Thus, expression patterns of cell cycle-related proteins were investigated in the early phase of differentiated-type gastric cancers to ascertain any mechanistic relationships with mucin phenotypes.

Methods

Immunostaining for Cyclins D1, A, E, and p21, p27, p53 and β-catenin was used to examine impairments of the cell cycle in 190 gastric intramucosal differentiated-type cancers. Mucin phenotypes were determined by the expressions of MUC5AC, MUC6, MUC2 and CD10. A Ki-67 positive rate (PR) was also examined.

Results

Overexpressions of p53, cyclin D1 and cyclin A were significantly more frequent in a gastric phenotype than an intestinal phenotype. Cyclin A was overexpressed in a mixed phenotype compared with an intestinal phenotype, while p27 overexpression was more frequent in an intestinal phenotype than in a mixed phenotype. Reduction of p21 was a common feature of the gastric intramucosal differentiated-type cancers examined.

Conclusions

Our results suggest that the levels of some cell cycle regulators appear to be associated with mucin phenotypes of early gastric differentiated-type cancers.

Evaluation of cell cycle protein expression in gastric cancer: cyclin B1 expression and its prognostic implication

The cell cycle progression is regulated by interactions of specific cyclin-dependent kinases at the G1-S and G2-M checkpoints. In addition, the cell cycle dysregulation plays a major role in carcinogenesis of human cancers. To investigate the role of cell cycle regulators in the pathogenesis and progression of human gastric cancer, the expression of cyclin D1, A, B1, p16(INK4a), p21(CPI1), p27(KIP1), p53, and pRb was investigated in 482 gastric carcinomas using immunohistochemistry in terms of histologic type, tumor invasion, size, location, and metastatic behavior. The cyclin D1, A, and B1 expression (>10%) was observed in 49%, 69%, and 49% of the cases, respectively. Negative cases for p16(INK4a), p21(CPI1), and p27(KIP1) were detected in 90%, 86%, and 50.5%. There were 30% and 68% of the gastric tumors positive for p53 and pRb, respectively. Diffuse carcinomas frequently were positive for cyclin B1 and pRb, and negative for p21. A relationship between p53 expression and intestinal type carcinomas was found. In addition, the expression of cyclin B1 was associated with regional lymph node metastasis and poor prognosis. No relationship was noticed between any other cell cycle proteins expression and age, sex, tumor size, tumor location, and lymph node involvement. These findings have shown alterations in several cell cycle regulators, and it was suggested that cyclin B1 expression is closely associated with poor behavior in gastric cancer.

Metastasis-associated protein S100A4 and p53 predict relapse in curatively resected stage III and IV (M0) gastric cancer

PURPOSE

Pathologic stage is the most important predictive factor of relapse in gastric cancer after curative resection. However, patients with the same stage often have different risks of relapse. Here, we investigated whether the expressions of molecular markers can supplement the current staging system in terms of relapse prediction.

PATIENTS AND METHODS

One hundred and nine stage III or IV (M0) patients who had received curative gastrectomy followed by adjuvant 5-fluorouracil and cisplatin chemotherapy were included in this study. The expressions of molecular markers including p53, p27, COX-2, HER-2, EGFR, maspin, S100A4, E-cadherin, Sp1, and p97 were analyzed by immunohistochemistry in cancer and paired normal tissues.

RESULTS

The overall relapse rate was 58.7%, and pathologic stage was a significant predictive factor of relapse (42% in stage IIIA, 48% in IIIB, 76% in IV, p = 0.005). Of the 10 markers examined, p53 and S100A4 were expressed only in tumor tissues, and S100A4 expression was significantly associated with a higher relapse rate (85% vs. 53%, p = 0.008). In multivariate analysis including tumor stage, S100A4 and p53 expression were independent predictive factors of relapse (relative risk, 6.98; 95% confidence interval [CI], 1.608-30.342, 3.49; 95% CI, 1.328-9.186, respectively). On comparing patients who expressed S100A4 or p53 with those who expressed neither, relapse rates were 58% vs. 25% in stage III (p = 0.011) and 95% vs. 59% in stage IV (M0) (p = 0.003).

CONCLUSION

In addition to staging system, the expressions of S100A4 and p53 were significant predictive factors of relapse in gastric cancer after curative resection and adjuvant chemotherapy.

Immunohistochemical similarities between pancreatic mucinous cystic tumor and ovarian mucinous cystic tumor

OBJECTIVE

Pancreatic mucinous cystic tumor (MCT(P)) and ovarian mucinous cystic tumor (MCT(O)) show common features. However, there are few studies showing a comparison of both types of tumor. We immunohistochemically studied both types of tumor to clarify their characteristics.

METHODS

Eight patients with MCT(P) and 21 patients with MCT(O) were examined. The tumors were immunohistochemically examined using antibodies against female sex hormone receptors (estrogen receptor, progesterone receptor, and alpha-inhibin), pancreatobiliary tissue markers (carbohydrate antigen 19-9 and DUPAN2) and cell cycle regulators (p27kip1 and phosphorylated retinoblastoma). Samples from 7 female patients with invasive pancreatic ductal carcinoma (DC), 8 female patients with normal pancreatic tissue, and 10 patients with normal ovarian tissue were also examined.

RESULTS

In the tumor epithelial cells, the expressions of DUPAN2 and p27/kip1 were similar between MCT(P) (38% and 88%, respectively) and MCT(O) (14% and 76%, respectively), but significantly different between both tumors and DC (100% and 0%). In the stromal cells, the expressions of estrogen receptor, progesterone receptor, alpha-inhibin, and p27/kip1 were similar between MCT(P) (63%, 75%, 50%, and 63%, respectively) and MCT(O) (57%, 71%, 81%, and 57%, respectively), but significantly different between both tumors and DC (0%, 0%, 0%, and 0%, respectively).

CONCLUSIONS

MCT(P) and MCT(O) have several immunohistochemical similarities and are significantly different from DC. The female sex hormone system may play a major role in the development of both MCT(P) and MCT(O). A frequent p27/kip1 expression level was associated with nonaggressive progression of both tumors.

Prevalence of p21 immunohistochemical expression in esophageal adenocarcinoma

BACKGROUND

In western societies, the prevalence of adenocarcinoma of the gastroesophageal junction has increased in recent years. It is commonly accepted today that esophageal adenocarcinoma develops from a premalignant lesion: Barrett's esophagus. This type of carcinoma is hardly diagnosed at early stages, which results in significant mortality. Molecular biology studies have shown that most malignant tumors originate from the interaction between inherited characteristics and external factors, which may cause genetic changes that interfere with the control over the differentiation and growth of cells in susceptible individuals. p21 (WAF1/CIP1) has a key role in the regulation of the cell cycle, and its immunohistochemical expression has been investigated in several tumors, showing that it influences the prognosis of various neoplasms.

AIM

To check the prevalence of p21 protein expression in patients with esophageal adenocarcinoma diagnosed in the last 5 years by the Group for Surgeries of the Esophagus and Stomach of "Hospital de Clínicas de Porto Alegre", RS, Brazil.

METHODS

The study population consisted of 42 patients with esophageal adenocarcinoma diagnosed by the Group for Surgeries of the Esophagus and Stomach between January 1998 and December 2002. The expression of p21 protein was determined by immunohistochemistry using primary antibody, p21, clone SX118, code M7202 (Dako), and assessed according to the immunoreactive scoring system.

RESULTS

Of 42 analyzed patients, 83.3% were male and older than 40 years. Among these, 56.2% were submitted to curative resection: total gastrectomy and transhiatal esophagogastrectomy. The remaining patients were submitted to palliative surgery or did not undergo any surgical treatment. Only five patients received adjuvant chemotherapy and radiation therapy, either alone or combined. Advanced disease (stages III and IV) was detected in 78.6% of the patients. Only nine patients were positive for p21, according to the immunoreactive scoring system.

CONCLUSION

p21 was expressed in 9 of 42 patients (21.4%) with esophageal adenocarcinoma diagnosed in the last 5 years by the Group for Surgeries of the Esophagus and Stomach of Hospital de Clínicas de Porto Alegre. In our patient population, the accumulation of p21 did not play a key role in the carcinogenesis of esophageal adenocarcinoma.

Analysis of molecular pathological factors of unfavorable prognosis for young cervical cancer patients

The aim of this study was to explore the molecular pathological characteristics of cervical cancer in women aged below 35, disclose the factors that indicate the unfavorable prognosis, and provide some useful targets for improving therapeutic outcome.

PATIENTS AND METHODS

64 cases of pathological data originating from cervical cancer patients aged below 35 served as the study group to perform a retrospective research, and pathological data from 90 cases of cervical cancer patients beyond age 35, who underwent treatment during the same time, were selected at random as the reference group. Immunohistochemistry and quantified image analysis were utilized to detect synchronously the protein expression difference of survivin and p27 between the 2 groups.

RESULTS

The total 5-year survival rate of the study group was 65.6% compared to 84.4% in the reference group, while the lymph node metastasis rate was 25% compared to 12.2% in the reference group. Both differences were statistically significant (p < 0.05). Survivin expression is much greater in the study group than in the reference group (p < 0.05); there is no statistical difference of the p27 expression between the 2 groups (p > 0.05), but p27 expression is related to lymph node metastasis.

CONCLUSION

Younger female patients have a worse prognosis than older ones, and survivin expression is associated with poor prognosis. Targeting these molecular factors may lead to a hopeful biomedical therapy to improve the prognosis of young female cervical cancer patients.

P21/WAF1 is an independent survival prognostic factor for patients with hepatocellular carcinoma after resection

BACKGROUND/AIMS

The cyclin kinase inhibitor p21/WAF1 is regulated by p53-dependent or independent pathways and inhibits the action of proliferating cell nuclear antigen (PCNA). The prognostic role of p21/WAF1 in hepatocellular carcinoma (HCC) is ambiguous. To further clarify this, we examined the expression of three genes in HCC.

METHODS

A total of 122 resected HCC specimens were collected from 1987 to 1998. Expression of p21/WAF1, p53, and PCNA in HCC was analysed by immunohistochemistry.

RESULTS

Immunoreactivity was detectable for p21/WAF1 in 37%, and for p53 in 41.8% of HCCs. Positive expression of both genes does not relate to each other, but both are associated with a high PCNA labelling index (LI) (P<0.05) in tumour. p53 (+) is also associated with high serum alpha-foetoprotein (alphaFP) (P<0.001), tumour dedifferentiation (P=0.001) and advanced pathologic stages (P=0.017). However, p21/WAF1 (+) did not show clinicopathologic significance. Survival analysis indicated that poor prognostic factors were p21/WAF1 (-) (P=0.024), p53 (+) (P=0.008), high PCNA (P<0.001), tumour without capsule (P=0.001), poor tumour differentiation (P=0.004), advanced pathologic stage (P<0.001), and high serum alphaFP(P<0.001). Independent factors were p21/WAF1 expression, pathologic stage, and PCNA.

CONCLUSION

In HCC, increased proliferation index PCNA is significantly associated with positive p53 and p21/WAF1. But p21/WAF1 expression did not relate to p53 expression. P21/WAF1 (+) is a good event and serves as an independent survival prognostic factor for HCC, which is a novel finding apart from previous reports.

Prognostic significance of p21WAF1/CIP1, p27Kip1, p53 and E-cadherin expression in gastric cancer

BACKGROUND

Gastric carcinoma is characterised by numerous genetic and epigenetic alterations that influence cell cycle progression, apoptosis and DNA repair. These alterations include down-regulation of the cyclin-dependent kinase (CDK) inhibitors p21(WAF1/CIP1) and p27(Kip1), and mutations of the tumour suppressor protein p53 and the cell adhesion molecule E-cadherin. Combined evaluation of the prognostic significance of these alterations has not been reported in Mexican Mestizo patients.

AIMS

To evaluate p21(WAF1/CIP1), p27(Kip1), p53 and E-cadherin protein expression, including mutant E-cadherin variants with deletion of exon 8 (del 8) or 9 (del 9), in gastric cancer from Mexican patients.

METHODS

Immunohistochemistry for the above-mentioned markers, including mutation-specific E-cadherin antibodies, was carried out in 69 gastric carcinomas; expression levels were correlated with histotype, tumour stage and prognosis.

RESULTS

Expression of p21(WAF1/CIP1) alone or in combination with p27(Kip1) or in the absence of p53 was associated with favourable prognosis. Staining of del 8 and del 9 E-cadherin was found exclusively in patients negative for p53 and positive for p21(WAF1/CIP1), suggesting that the p21(WAF1/CIP1) regulatory function of p53 was intact.

CONCLUSION

Combined evaluation of the prognostic significance of cell cycle regulators and E-cadherin should be performed. Even though patients negative for p53 and positive for p21(WAF1/CIP1) have a favourable prognosis, it may have a negative influence on prognosis if they acquire in addition E-cadherin mutations which have been shown previously to be associated with poor survival.

Immunohistochemical analysis of pRb2/p130, VEGF, EZH2, p53, p16(INK4A), p27(KIP1), p21(WAF1), Ki-67 expression patterns in gastric cancer

Although the considerable progress against gastric cancer, it remains a complex lethal disease defined by peculiar histological and molecular features. The purpose of the present study was to investigate pRb2/p130, VEGF, EZH2, p53, p16(INK4A), p27(KIP1), p21(WAF1), Ki-67 expressions, and analyze their possible correlations with clinicopathological factors. The expression patterns were examined by immunohistochemistry in 47 patients, 27 evaluated of intestinal-type, and 20 of diffuse-type, with a mean follow up of 56 months and by Western blot in AGS, N87, KATO-III, and YCC-2, -3, -16 gastric cell lines. Overall, stomach cancer showed EZH2 correlated with high levels of p53, Ki-67, and cytoplasmic pRb2/p130 (P < 0.05, and P < 0.01, respectively). Increased expression of EZH2 was found in the intestinal-type and correlated with the risk of distant metastasis (P < 0.05 and P < 0.01, respectively), demonstrating that this protein may have a prognostic value in this type of cancer. Interestingly, a strong inverse correlation was observed between p27(KIP1) expression levels and the risk of advanced disease and metastasis (P < 0.05), and a positive correlation between the expression levels of p21(WAF1) and low-grade (G1) gastric tumors (P < 0.05), confirming the traditionally accepted role for these tumor-suppressor genes in gastric cancer. Finally, a direct correlation was found between the expression levels of nuclear pRb2/p130 and low-grade (G1) gastric tumors that was statistically significant (P < 0.05). Altogether, these data may help shed some additional light on the pathogenetic mechanisms related to the two main gastric cancer histotypes and their invasive potentials.

Rebamipide inhibits gastric cancer cell growth

Rebamipide is an antiulcer drug used in Japan, Korea, China, Philippines, and other Asian countries for treatment of gastritis and peptic ulcer. Its effect on gastric cancer cell growth and its regulatory mechanisms remain unknown. We examined whether rebamipide affects human gastric cancer cell proliferation and activation of Smad signaling pathway. Gastric cancer (AGS) cells were treated with either (a) medium (control), (b) medium-containing rebamipide (0.5-2 mg/mL), or (c) PD98059+rebamipide. We determined cell proliferation, expression of p21, phosphorylation of ERK2, JNK p38, and Smad2/3, formation of Smad2/3-Smad4 complex, and nuclear translocation of Smad2/3. Rebamipide treatment inhibited AGS cell proliferation and increased p21, Smad2/3 phosphorylation, and Smad2/3-Smad4 complex formation. Rebamipide induced phosphorylation of ERK2 but not JNK or p38. Inactivation of ERK2 by PD98059 partly attenuated rebamipide-induced p21 expression. These data demonstrate that rebamipide activates Smad signaling pathway and suppresses human gastric cancer cell growth. Inactivation of ERK2 partly inhibited rebamipide-induced p21 expression, indicating a crosstalk between ERK and Smad signaling pathways.

p27 downregulation and metallothionein overexpression in gastric cancer patients are associated with a poor survival rate

BACKGROUND AND OBJECTIVES

As a significant number of curatively treated gastric cancer patients will ultimately relapse, there is an urgent need to investigate new prognostic markers for identification of high-risk patients. In this study, we investigated the possible role of molecular markers involved in cell cycle regulation (B1 and D3 cyclins, and p27) and cell protection (metallothionein, MT) in predicting tumor behavior and clinical outcome in gastric cancer patients.

METHODS

Analysis of the above indicators was performed by immunohistochemistry on 73 gastric cancer patient samples and 25 normal gastric mucosa specimens.

RESULTS

Normal gastric mucosa cells displayed low expressions of B1 and D3 cyclins and MT, and intense p27 staining. Conversely, gastric tumor cells showed higher cyclin D3 and MT, and lower p27 expressions. B1 cyclin expressions were not different between normal and tumor tissue. p27 and MT expressions were altered in almost all cancer samples, and were strongly correlated with tumor progression. Advanced extent of the primary tumor, nodal metastasis, low p27, and high MT expressions were the best combination of variables for prediction of poor clinical outcome. Each marker predicted outcome better than staging based on tumor-node (TNM) system. Survival and recurrence rates decreased as molecular alterations increased. Finally, molecular profile determination correctly predicted the prognosis in patients with same TNM stage.

CONCLUSIONS

p27 and MT expressions strongly correlated with clinical outcome allowing to identify an unfavorable group of patients that may benefit from tailored treatments. The role of B1 and D3 cyclins in gastric cancer remains to be elucidated.

Down-expression of tumor protein p53-induced nuclear protein 1 in human gastric cancer

AIM: Overexpression of tumor protein p53-induced nuclear protein 1 (TP53INP1) induces G₁ cell cycle arrest and increases p53-mediated apoptosis. To clarify the clinical importance of TP53INP1, we analyzed TP53INP1 and p53 expression in gastric cancer.

METHODS: TP53INP1 and p53 expression were examined using immunohistochemistry in 142 cases of gastric cancer. The apoptosis of gastric cancer cells was analyzed using the TUNEL method. The relationship between the expression of TP53INP1 and clinicopathological factors was statistically analyzed.

RESULTS: TP53INP1 was expressed in 98% (139/142 cases) of non-cancerous gastric tissues and was down-expressed in 64% (91/142 cases) of gastric cancer lesions from the same patients. TP53INP1 expression was significantly decreased (43.9%) in poorly differentiated adenocarcinoma compared with well or moderately differentiated adenocarcinoma (81.6%). Cancers invading the submucosa or deeper showed lower positively (59.1%) compared with mucosal cancers (85.2%). Decrease or loss of TP53INP1 expression was significantly correlated with lymphatic invasion (54.3% vs 82.0% without lymphatic invasion) and node-positive patients (31.3% vs 68.3% in node-negative patients). P53 was expressed in 68 (47.9%) patients of gastric cancer, whereas it was absent in normal gastric tissues. A significant association was also observed between TP53INP1 status and the level of apoptosis in tumor cells: the apoptotic index in TP53INP1-positive tissues was significantly higher than that in TP53INP1-negative portions. Finally, when survival data were analyzed, loss of TP53INP1 expression had a significant effect in predicting a poor prognosis (P = 0.0006).

CONCLUSION: TP53INP1-positive rate decreases with the progression of gastric cancer. TP53INP1 protein negativity is significantly associated with aggressive pathological phenotypes of gastric cancer. TP53INP1 is related to the apoptosis of gastric cancer cells. The decreased expression of the TP53INP1 protein may reflect the malignant grade of gastric cancer and is regarded as an adverse prognostic factor.

p27kip1 deficiency confers susceptibility to gastric carcinogenesis in Helicobacter pylori-infected mice

BACKGROUND & AIMS

Determining how Helicobacter pylori promotes gastric cancer and whether H pylori eradication decreases cancer risk would be helped by suitable murine models. Mice lacking the cyclin-dependent kinase inhibitor p27kip1 are susceptible to carcinogen-induced tumors. Furthermore, p27 stimulates gastric epithelial apoptosis and inhibits proliferation, expression is decreased by H pylori, and low levels are associated with a poor prognosis in gastric cancer. We therefore evaluated p27-deficient mice as a model for H pylori-associated gastric cancer.

METHODS

Wild-type and p27-/- C57BL/6 mice were infected with H pylori mouse-adapted Sydney strain at 6-8 weeks of age and 6-10 mice of each type were euthanized 15, 30, 45, 60, and 75 weeks later.

RESULTS

Uninfected p27-/- mice developed gastric hyperplasia. H pylori-infected p27-/- mice frequently developed intestinal metaplasia (40% at 30 weeks, 67% at 45 weeks), and after 60 weeks 7 of 12 mice developed significant dysplasia and gastric cancer, recapitulating human intestinal-type gastric carcinogenesis. Wild-type mice developed intestinal metaplasia only after 75 weeks of infection; significant gastric dysplasia was observed in 1 animal (P < .05 for each comparison with p27-/- mice). No disease developed in uninfected mice. H pylori infection in p27-/- mice was associated with significantly decreased apoptosis and increased epithelial proliferation, inflammation, and H pylori density compared with infection in wild-type mice.

CONCLUSIONS

p27 loss and H pylori colonization cooperate to produce gastric cancer. The p27-deficient mouse affords opportunities to examine the pathogenesis of H pylori in gastric carcinogenesis and to test eradication and chemopreventive strategies.

The prognostic significance of p53, p27 kip1, p21 waf1, HER-2/neu, and Ki67 proteins expression in gastric cancer: a clinicopathological and immunohistochemical study of 121 Arab patients

BACKGROUND

The variability of prognosis within a pathological stage of gastric cancer (GC) at presentation, underscores the need for specific biological markers to identify subgroups of patients with aggressive course for intensive treatment. To our knowledge, this is the first study from an Arab population reporting on the relationship of p53, p27 kip1, p21 waf1, HER-2/neu, and Ki67 expression, and clinicopathological features and their prognostic significance.

METHODS

Formalin-fixed paraffin-embedded tumors were studied by immunohistochemistry, using monoclonal antibodies to p53, p27 kip1, p21 waf1, HER-2/neu, and Ki67. The results were correlated with clinicopathological features and survival.

RESULTS

M:F = 80:41; median age = 60 years; stage III and IV = 71%; and median follow-up = 34.4 months. Positive expression rates of p53, p27 kip1, p21 waf1, Ki67, and HER-2/neu were 54%, 40%, 8.3%, 70%, and 12% respectively. p53 expression correlated with age <60 years (P = 0.03), tumor size >5 cm (P = 0.01), p27 kip1 and Ki67 expression (P = 0.0001), and HER-2/neu (P = 0.04). p21 waf1 correlated inversely with T-stage (P = 0.008) and Her-2/neu expression correlated with histological grade (P = 0.04) and T-stage (P = 0.008). Univariate analysis showed that p53 overexpression (P = 0.01), fungating and infiltrative macroscopic appearance (P = 0.02), size >5 cm (P = 0.0001), lymph node metastasis (P = 0.0001), p T3 and T4 disease (P = 0.01), and overall stage III and IV (P = 0.0001) disease were adverse prognostic factors. Patients with tumor profiles p53 (-)/p27 (+) had better survival than those with p53 (+)/p27 kip1 (-)(P = 0.02). On multivariate analysis by Cox regression model, the expression of p53 (P = 0.03) and lymph node involvement (P = 0.01) were significant adverse prognostic factors for overall survival.

CONCLUSIONS

The expression of p53 in Arab patients with GC correlates with aggressive tumor characteristics and is an independent prognostic factor. The combined analysis of p53 and p27 kip1 is of added prognostic value.

Immunohistochemical study of cell cycle-associated proteins in adenocarcinoma of the uterine cervix treated with radiotherapy alone: P53 status has a strong impact on prognosis

PURPOSE

Because the incidence of adenocarcinoma of the uterine cervix has recently risen, the evaluation of radiotherapy (RT) for this disease has become an increasingly urgent matter. We analyzed the expression of the cell cycle-associated proteins p53, p27, p21/waf1/cip1, and cyclin D1 in cervical adenocarcinomas in correlation with the prognostic significance in tumors treated with RT alone.

METHODS AND MATERIALS

The expression of p53, p27, p21/waf1/cip1, and cyclin D1 was studied using an immunohistochemical method in 53 cases of cervical adenocarcinoma treated only with RT. Patients received RT alone between 1965 and 1994. The mean patient age was 61.8 +/- 12.6 years (range, 36-82 years). The number of patients with Stage I, II, III, and IVA disease was 6, 16, 28, and 3, respectively.

RESULTS

The number of patients with p53, p27, p21/waf1/cip1, and cyclin D1 positive tumors was 24, 18, 22, and 8, respectively; no statistically significant correlation was noted. The 5-year disease-free survival rate of p53-positive patients was 30%, significantly lower than the 62% for the p53-negative patients (p = 0.02); no statistically significant correlation was noted between disease-free survival and p27, p21/waf1/cip1, and cyclin D1 expression. No statistically significant correlation was observed between local control and expression of any of the proteins.

CONCLUSION

Expression of p53 protein has a statistically significant impact on disease-free survival in adenocarcinoma of the uterine cervix treated with RT alone. However, the clinical significance of p27, p21/waf1/cip1, and cyclin D1 protein expression was not obvious.

Expression of p21(WAF1) and p53 and polymorphism of p21(WAF1) gene in gastric carcinoma

AIM

To investigate the relationship between expression of p21(WAF1) and p53 gene, and to evaluate the deletion and polymorphism of p21(WAF1) gene in gastric carcinoma (GC).

METHODS

Expression of p21 and p53 proteins, and deletion and polymorphism of p21 gene in GC were examined by streptavidin-peroxidase conjugated method (SP) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) respectively.

RESULTS

The expression of p21 and p53 was found in 100% (20/20) and 0% (0/20) of normal gastric mucosae(NGM), 92.5% (37/40) and 15.0% (6/40) of dysplasia (DP) and 39.8% (43/108) and 56.5% (61/108) of GC, respectively. The positive rate of p21 in GC was lower than that in NGM and DP (P<0.05), while the positive rate of p53 in GC was higher than that in NGM and DP (P<0.05). p21 and p53 were significantly expressed in 63.3% (19/30) and 36.7% (11/30), 35.0% (14/40) and 77.5% (31/40), 26.7% (4/15) and 80.0% (12/15), 30.8% (4/13) and 30.8% (4/13), and 20.0% (2/10) and 30.0% (3/10) of well-differentiated, poorly-differentiated, undifferentiated carcinomas, mucoid carcinomas and signet ring cell carcinomas. The expression of p21 in well-differentiated carcinomas was significantly higher than that in poorly-differentiated, un-differentiated, mucoid carcinomas and signet ring cell carcinomas (P<0.05). Contrarily, The expression of p53 was increased from well-differentiated to poorly-differentiated and un-differentiated carcinomas (P<0.05). The expression of p21 and p53 in paired primary and metastatic GC (35.3% and 70.6%) was different from non-metastatic GC (62.5% and 42.5%) markedly (P<0.05). The expression of p21 in invasive superficial muscle (60.0%) was higher than that in invasive deep muscle or total layer (35.2%) (P<0.05) and was higher in TNM stages I (60.0%) and II (56.2%) than in stages III (27.9%) and IV (22.2%) (P<0.05), whereas the expression of p53 did not correlate to invasion depth or TNM staging (P>0.05). The exoression patterns of p53+/p21-, and of p53-/p21+ were found in 5.0% and 82.5% of DP. There was a significant correlation between expression of p21 and p53 (P<0.05). But there was no significant correlation between expression of both in GC (P>0.05). There was no deletion in exon 2 of p21 gene in 30 cases of GC and 45 cases of non-GC, but polymorphism of p21 gene at exon 2 was found in 26.7% (8/30) of GC and 8.9% (4/45) of non-GC, a significant difference was found between GC and non-GC (P<0.05). There was no significant relation between p21 expression of polymorphism (37.5%, 3/8) and non-polymorphism (45.5%, 10/22) in GC (P>0.05).

CONCLUSION

The loss of p21 protein and abnormal expression of p53 are related to carcinogenesis, differentiation and metastasis of GC. The expression of p21 is related to invasion and clinical staging in GC intimately. The expression of p21 protein depends on p53 protein largely in NGM and DP, but not in GC. No deletion of p21 gene in exon 2 can be found in GC. The polymorphism of p21 gene might be involved in gastric carcinogenesis.There is no significant association between polymorphism of p21 gene and expression of p21 protein.

Expression of the Components of the Cip/Kip Family in Malignant Lymphoma of the Thyroid

OBJECTIVE

For evaluating the characteristics of human neoplasms, investigation of regulators of cell cycle progression is important. We studied three components of the Cip/Kip family, p57, p27 and p21, in malignant lymphomas of the thyroid.

METHODS

We immunohistochemically investigated the expression of the three proteins for 49 cases of thyroid lymphomas, as well as 10 cases of chronic thyroiditis.

RESULTS

In infiltrating lymphocytes in chronic thyroiditis, p57 and p27 were diffusely expressed, whereas p21 immunoreactivity was only occasionally observed. In lymphoma, decreased expression of p57 (less than 50% of lymphoma cells were positive) was observed in 24 cases (49.0%). p57 expression was inversely linked to the MIB-1 labeling index, grade of malignancy and aberrant p53 expression. Decreased expression of p27 was observed in 25 cases (51.0%), which was also related to the MIB-1 labeling index and aberrant p53 expression. On the other hand, p21 expression was occasional, and when the cut-off value was set at 3%, 38 cases (77.6%) were regarded as negative. P21 expression was not linked to any clinicopathological parameters.

CONCLUSION

These findings suggest that, among the 3 components of the Cip/Kip family, p57 and p27 play a role in negatively regulating the cell proliferation of thyroid lymphoma cells and decreased expression of them contributes to the progression of this disease.

p27 Protein and cancers of the gastrointestinal tract and liver: an overview

GOALS

The purpose of this review is to look at the evidence presented in the literature on the immunoexpression of p27 in cancers of the gastrointestinal tract and liver.

BACKGROUND

Cell cycle proteins have been shown to play an important role in the oncogenesis of many tumors. Several of these proteins have been examined in concert and in isolation, and some have been put forward as putative tumor markers. p27, which is an important inhibitory protein in the cell cycle and belonging to a group of cyclin-dependent kinase inhibitors, has also been studied in several malignancies, most notably breast, lung, bladder, and prostate cancers. Considerable work has also been done on the expression of this protein in cancers occurring within the gastrointestinal tract.

RESULTS

Cancers occurring in the major sites of the gastrointestinal tract (esophagus, stomach, and colorectum) and liver show a similar pattern with regard to p27 protein levels. p27 emerges as a statistically significant predictor of survival and tumor behavior. It has been suggested that p27 loss occurs early in the carcinogenesis process, with dysplastic epithelium having decreased expression. The more aggressive, metastasizing cancers tend to lack p27 expression as well. Some studies have also invoked the subcellular localization of p27 (cytoplasmic versus nuclear) as also being of prognostic value.

CONCLUSION

Therefore, in gastrointestinal and hepatic cancers, low p27 expression is regarded as an important adverse prognostic factor.

TP53 and gastric carcinoma: a review

In this article, we survey the major p53 (TP53) alterations identified in gastric carcinomas and their precursors. These include p53 expression, mutations, and loss of heterozygosity (LOH). Not only are the various abnormalities summarized, but in addition there is a survey of the literature with respect to the impact of these changes on patient prognosis and treatment response. The majority of published studies involve the immunohistochemical detection of the protein. These use different antibodies, different detection techniques, and different methods of interpretation. Therefore not surprisingly, the results of many of the studies are contradictory with one another. Overall, however, it appears that p53 alterations occur early in the development of gastric carcinoma, being present even in the nonneoplastic mucosa and they increase in frequency as one progresses along the pathway of gastric carcinoma development. p53 immunoreactivity is seen in 17%-90.7% of invasive gastric carcinomas. p53 alterations occur much more commonly in proximal lesions than in distal ones, suggesting that the molecular events leading to the development of gastric carcinoma may be very different in proximal vs. distal tumors. p53 mutations occur in 0%-77% of gastric carcinomas. The mutations are distributed widely across the gene from exons 4-11 with hot spots of mutation at codons 175, 248, 273, 282, 245, and 213. G:C>A:T transitions at CpG sites are the commonest type of mutation. At least 60% of carcinomas with mutations also exhibit p53 LOH.

Prognostic significance of matrix metalloproteinase-7 (MMP-7) expression at the invasive front in gastric carcinoma

To evaluate the clinicopathological significance of matrix metalloproteinase-7 (MMP-7) expression in gastric carcinoma, we investigated immunohistochemically MMP-7 expression in 214 gastric carcinomas, and examined its relations with the clinicopathologic parameters including patient prognosis. MMP-7 expressed predominantly in cancer cells, and MMP-7-positive tumor cells were preferentially found in deeply invading nests, especially at the invasive front. The mean MMP-7 labeling index (LI) at the invasive front was significantly higher in tumors invading or penetrating the muscularis propria and in stages II - IV than within the submucosal layer and in stage I, respectively (P < 0.001). Statistical analysis revealed that MMP-7 LI at the invasive front was related to lymph node metastasis, vascular invasion, and lymphatic permeation, when all 214 cases were examined as one group (P < 0.05 for all), and the cases with high MMP-7 expression at the invasive front showed significantly more unfavorable prognosis as compared with that of low MMP-7 expression tumors (P < 0.01). Multivariate analysis revealed that TNM stage and MMP-7 expression status at the invasive front were independent prognostic factors (P = 0.0017, relative risk (RR) = 3.12; P = 0.0019, RR = 2.67, respectively). Our findings indicated that expression of MMP-7 at the invasive front is closely associated with local invasiveness, and might be a reliable prognostic marker for patients with gastric carcinoma.