Decreased expression of CDH1 or CTNNB1 affects poor prognosis of patients with esophageal cancer

Background

E-cadherin/CDH1 is one of the proteins involved in cell adhesion, and it is known that decreased expression of E-cadherin induces lymph node metastasis in esophageal cancer. Beta catenin/CTNNB1, which is an important component of the Wnt signaling pathway, binds to E-cadherin at the cell membrane, where the complex of these two proteins functions in the stabilization of cell adhesion. However, its role in the pathogenesis of esophageal cancer is still unknown.

Methods

This study included 86 patients with esophageal cancer who underwent surgery between 1998 and 2007. The expression of the E-cadherin/CDH1 gene product (E-cadherin/CDH1) and that of the beta catenin/CTNNB1 protein in the cell membrane were analyzed by immunohistochemistry. We examined the correlations among CDH1 or CTNNB1 expression, clinicopathological factors, and the prognosis of patients with ESCC.

Results

CDH1 and CTNNB1 were expressed in 52.3 % (45/86) and 36.0 % (31/86) of tumor samples, respectively. Both CDH1 and CTNNB1 were co-expressed in 22.1 % (19/86) of esophageal cancer tissues. CDH1 expression correlated with the p-stage (stages I–II vs stages III–IV, p = 0.032), T factor (T1–2 vs T3–4, p = 0.0088), and lymphatic invasion (p = 0.019). However, CDH1 expression did not correlate with the N factor or the blood vessel invasion. CTNNB1 expression correlated with the T factor (T1–2 vs T3–4, p = 0.0015), p-stage (stages I–II vs stages III–IV, p = 0.030), and lymphatic invasion (p = 0.007). The CDH1(+)/CTNNB1(+) phenotype was inversely correlated with the T factor, N factor, p-stage, lymphatic invasion, and blood vessel invasion. Furthermore, patients whose tumors were double-positive for CDH1 and CTNNB1 had a significantly higher survival rate than those whose tumors were negative for CDH1 or CTNNB1 (log-rank test, p = 0.0192). The T factor and N factor had a strong negative correlation with double-positive tumors. These were both independent prognostic factors, as was the double-positive phenotype. A univariate analysis indicated that the T factor, the N factor, and CDH1 and CTNNB1 co-expression were significant variables that predicted survival (hazard ratio, 2.387; 95 % confidence interval, 1.115–5.102; p = 0.025).

Conclusions

Decreased expression of CDH1 or CTNNB1 in the cell membranes of cancer cells is associated with poor survival of patients with esophageal cancer.

Nuclear expression of TCF4/TCF7L2 is correlated with poor prognosis in patients with esophageal squamous cell carcinoma

The prognosis for patients with esophageal cancer remains poor. Therefore, the identification of novel target molecules for the treatment of esophageal cancer is necessary. Here, we investigated the clinicopathological significance of transcription factor 4/transcription factor 7-like 2 (TCF4/TCF7L2) in resectable esophageal squamous cell carcinoma (ESCC), because TCF4/TCF7L2 expression has not been studied in esophageal cancer previously.

This study included 79 patients with esophageal cancer who underwent surgery between 1998 and 2005. The expression of the TCF4/TCF7L2 protein in the nucleus of esophageal cancer cells was analyzed using immunohistochemistry. We examined the correlation between TCF4/TCF7L2 expression, clinicopathological factors, and prognosis in patients with ESCC.

TCF4/TCF7L2 was expressed in 57 % (45/79) of patients. TCF4/TCF7L2 expression was correlated with T factor (T1 vs. T2-4, p = 0.001), stage (I vs. II-IV, p =0.0058), Ly factor (p =0.038), and V factor (p =0.038) and did not correlate with age, gender or N factor. Furthermore, patients who were positive for TCF4/TCF7L2 had a significantly lower survival rate than those who were negative for TCF4/TCF7L2 (log-rank test, p = 0.0040). TCF4/TCF7L2 expression significantly affected the survival of patients with ESCC. Positive expression of TCF4/TCF7L2 was correlated with a poor prognosis after a curative operation in patients with ESCC.

Use of bioabsorbable staple reinforcement material in side-to-side anastomoses: Suture line reinforcement of the weak point of the anastomosis

BACKGROUND

Few studies have been designed regarding optimal reinforcement of the crotch of a side-to-side anastomosis. The purpose of this study was to clarify the weak point of the side-to-side anastomosis and to evaluate the effect of bioabsorbable reinforcement material.

METHODS

Fresh pig small bowel was used for all experiments. A side-to-side anastomosis was performed using a linear stapler, and the burst pressure of the anastomosis was measured. Three separate experiments were done. In experiment 1, the weak point and the burst pressure of that point were defined. In experiment 2, the burst pressure of the side of the anastomosis was measured. In experiment 3, we evaluated the effect of Neoveil(®) to strengthen the weak point of the anastomosis.

RESULTS

The weak point of the side-to side anastomosis was the crotch and the burst pressure was 39.8 ± 5.7 mmHg. The burst pressure of the side of the anastomosis was 109.9 ± 7.9 mmHg. This was significantly higher than the burst pressure of the crotch (P = 0.008). The burst pressure of the crotch in the group with Neoveil(®) was 83.3 ± 14.9 mmHg. This pressure was significantly higher than the group with no Neoveil(®) reinforcement (P = 0.001).

CONCLUSION

These findings suggest that the use of Neoveil(®) as a buttressing material is associated with reinforced staple lines and increased crotch burst pressures compared to non-buttressed staple lines. Neoveil(®) was found to perform comparably to clinically available buttress materials in this ex vivo model. Reinforcement of the weak point of the side-to-side anastomosis with Neoveil(®)may lead to fewer anastomotic leaks.

Ambulatory laparoscopic cholecystectomy: An audit of day case vs overnight surgery at a community hospital in Japan

AIM: To evaluate the applicability and safety of ambulatory laparoscopic cholecystectomy (LC) and to compare day case and overnight stay LC.

METHODS: Data were collected retrospectively and consecutively for day case and overnight stay LC patients from July 1, 2009 to April 30, 2011. Outcomes were analyzed for patient demographics, operation time, blood loss during operation and frequency and reasons for unexpected or prolonged hospitalization in each group.

RESULTS: There was no hospital mortality and no patient was readmitted with serious morbidity after discharge. 50 patients received a day case LC and 19 had an overnight stay LC. There was a significant difference in age between both groups (P < 0.02). There were no significant differences between the day case LC performed (n = 41) and failed (n = 9) groups and between the day case LC performed and the one night stay LC (n = 12) groups. There was a significant difference in age between the one night stay and more nights stay LC groups (P < 0.05). Thus, elderly patients showed a tendency to like to stay in hospital rather than being a day case. The proportion of unexpected or prolonged hospitalization was not significantly different between the day case and overnight stay LC groups, when the patient’s request was excluded.

CONCLUSION: Day case LC can be performed with a low rate of complications. In overnight stay patients, there are many who could be performed safely as a day case. Moreover, we need to take special care to treat elderly patients.

36 EFFECT OF DNA METHYLTRANSFERASE INHIBITOR, RG108, ON IN VITRO DEVELOPMENT AND ntES ESTABLISHMENT RATE IN CLONED MOUSE EMBRYOS

Somatic cell nuclear transfer technique increased expectations among many for its potential to advance the regenerative therapy field. Cloned embryos, however, exhibit several epigenetic abnormalities, such as low histone acetylation or high DNA methylation levels compared with normal fertilized embryos. Therefore, increasing histone acetylation or reducing DNA methylation levels in cloned embryos using chemical treatments may improve cloning efficiency. We recently succeeded in improving the success rate of mouse cloning by using class IIb histone deacetylase inhibitors, such as trichostatin A (TSA), scriptaid and suberoylanilide hydroxamic acid. It has also been reported that 5-aza-2′-deoxycytidine, a DNA methyltransferase inhibitor that is a chemical analogue of cytidine, inhibits the potential of embryos to develop into blastocysts and later to fetuses. In the present study, another DNA methyltransferase inhibitor RG108, which is thought to strongly interact with the DNMT1 active site to inhibit DNMT1 activity, was used to examine whether it could improve cloning efficiency. To determine the effects of RG108, cloned embryos were treated with 100 to 500 μM RG108. When cloned embryos were treated at the 1-cell stage (from artificial activation to 10 h, n = 219), the cloning efficiency was similar to the control group (8.2 vs 10.8%). On the other hand, when 500 μM RG108 was added to the culture medium from the 2-cell to morula/blastocyst stage (n = 113), although the developmental rate to blastocyst stage did not change significantly (79.6% vs 72.3%), higher Oct3/4 expression and more ICM cells were observed compared with non-treated, control cloned embryos. Moreover, we tried to establish ES cell lines from those cloned embryos and 11 ntES lines were generated from 21 blastocysts, which was higher than that of control (6 ntES cell lines from 20 blastocysts). All ntES lines showed AP staining positively. This finding showed that the quality of cloned mouse blastocysts increased when treated with a DNA methyltransferase inhibitor, suggesting a possible means for improving cloning efficiency in the future.

Aberrant nuclear localization of beta-catenin without genetic alterations in beta-catenin or Axin genes in esophageal cancer

Background

β-catenin is a multifunctional protein involved in two apparently independent processes: cell-cell adhesion and signal transduction. β-catenin is involved in Wnt signaling pathway that regulates cellular differentiation and proliferation. In this study, we investigated the expression pattern of β-catenin and cyclin D1 using immunohistochemistry and searched for mutations in exon 3 of the β-catenin gene and Axin gene in esophageal squamous cell carcinoma.

Materials and methods

Samples were obtained from 50 esophageal cancer patients. Immunohistochemical staining for β-catenin and cyclin D1 was done. Mutational analyses of the exon3 of the β-catenin gene and Axin gene were performed on tumors with nuclear β-catenin expression.

Results

Four (8%) esophageal cancer tissues showed high nuclear β-catenin staining. Overexpression of cyclin D1 was observed in 27 out of 50 (54%) patients. All four cases that showed nuclear β-catenin staining overexpressed cyclin D1. No relationship was observed between the expression pattern of β-catenin and cyclin D1 and age, sex, tumor size, stage, differentiation grade, lymph node metastasis, response to chemotherapy, or survival. No mutational change was found in β-catenin exon 3 in the four cases with nuclear β-catenin staining. Sequencing analysis of the Axin cDNA revealed only a splicing variant (108 bp deletion, position 2302–2409) which was present in the paired normal mucosa.

Conclusion

A fraction of esophageal squamous cell carcinomas have abnormal nuclear accumulation of β-catenin accompanied with increased cyclin D1 expression. Mutations in β-catenin or axin genes are not responsible for this abnormal localization of β-catenin.

Excision repair cross complementing 3 expression is involved in patient prognosis and tumor progression in esophageal cancer

The prognosis of patients with esophageal cancer remains poor. TNM classification is not sufficient to predict the prognosis. Therefore, novel predictive markers of the prognosis of esophageal cancer patients are awaited. The abnormality of the nucleotide excision repair (NER) is often involved in human cancers. Excision repair cross complementing 3 (ERCC3) contributes to NER. In esophageal cancer, ERCC3 expression has not been studied. Expression of ERCC3 was quantified by real-time reverse transcription polymerase chain reaction (RT-PCR) using LightCycler in 43 primary esophageal squamous cell carcinomas (ESCCs) and their paired normal esophageal mucosa. We examined the correlation between the ERCC3 expression and the clinicopathological factors and prognosis of ESCC patients. ERCC3 expression level was significantly correlated with the pathologic stage, tumor size and local invasiveness (t-factor) in esophageal cancer tissues. Reduced expression of ERCC3 was accompanied with tumor progression (p=0.0049) and higher pathologic stage (p=0.020). Moreover, ESCC patients with low ERCC3 mRNA expression had significantly shorter post-operative survival time than those with high expression (p=0.0003). In esophageal cancer, reduced expression of ERCC3 was correlated with local tumor progression and poor prognosis after operation.

Decreased expression of DFF45/ICAD is correlated with a poor prognosis in patients with esophageal carcinoma

BACKGROUND

DNA fragmentation factor 45 (DFF45)/inhibotor of caspase activated DNAse (ICAD) forms a complex with DFF40/CAD and inhibits its DNA cleaving function during apoptosis. DFF45 also functions as a chaperone for native DFF40 and is necessary for its function. It has been indicated that defects in the apoptotic pathway may exist in neoplastic cells.

METHODS

The authors investigated mRNA expression of DFF45 in a series of 46 esophageal squamous cell carcinoma (ESCC) specimens using polymerase chain reaction amplification. The results were correlated with the patients' clinicopathologic characteristics.

RESULTS

DFF45 mRNA expression was significantly lower in tumors with higher pathologic stage, higher tumor status (T status), lymph node metastasis, or more extensive lymphatic invasion. Patients who had low DFF45 mRNA expression (indicated by the ratio of DFF45 mRNA expression in tumor to DFF45 mRNA expression in normal esophageal mucosa [tumor:normal] < 1) had a significantly shorter survival after undergoing surgery compared with patients who had high DFF45 mRNA expression (tumor:normal > 1, P = 0.0006; log-rank test, P = 0.0003; median follow-up, 14.6 months).

CONCLUSIONS

Patients with ESCC with decreased DFF45 mRNA expression levels had a poor prognosis compared with patients who had high DFF45 mRNA expression levels.

Chfr expression is downregulated by CpG island hypermethylation in esophageal cancer

Cell cycle progression is monitored by checkpoint mechanisms to ensure the integrity of the genome and the fidelity of sister chromatid separation. Failure of such checkpoint functions results in genomic instability, a condition that predisposes cells to neoplastic transformation and tumor progression. Recently, Scolnick and Halazonetis defined a new mitotic checkpoint that acts at prophase and delays chromosome condensation in response to mitotic stress, and identified a gene, named checkpoint with FHA and ring finger (Chfr), that seems to be required for delaying prophase in human cells. In the present study, we examined human Chfr mRNA expression in 15 human esophageal cancer cell lines and 43 primary esophageal cancers to investigate the potential involvement of Chfr in the pathogenesis of esophageal cancers. We report here that a significant proportion of human esophageal cancer has loss of expression of Chfr gene. Furthermore, we found aberrant hypermethylation of the promoter region of this checkpoint gene in four of 15 (26.7%) esophageal cancer cell lines and in seven of 43 (16.3%) primary cancers.

Decreased peroxisome proliferator-activated receptor gamma gene expression is correlated with poor prognosis in patients with esophageal cancer

BACKGROUND

Peroxisome proliferator-activated receptor gamma (PPAR gamma) induces apoptosis by ligand stimulation in various tumor cell lines. In esophageal cancer cell lines, PPAR gamma activation also has suppressed the proliferation.

METHODS

In 55 primary esophageal squamous cell carcinomas (ESCCs) we examined the correlation between the expression of PPAR gamma mRNA with prognosis of esophageal cancer patients. The expression of PPAR gamma mRNA was quantified by real-time reverse transcription polymerase chain reaction using LightCycler. Immunohistochemistry was used to study the expression of PPAR gamma protein.

RESULTS

The expression of PPAR gamma mRNA was significantly decreased in esophageal cancer cells compared with normal esophageal mucosa (P = 0.0084). Among the clinical factors, PPAR gamma mRNA expression was lower in the tumors with extensive lymph node metastasis (n4) than those with less extensive lymph node metastasis (n0-3) (P = 0.0059). Patients with low PPAR gamma mRNA expression had significantly shorter postoperative survival time than those with high PPAR gamma mRNA expression (P = 0.0191). In immunohistochemistry, PPAR gamma protein was expressed in the nuclei of cells in some cases and expressed in the nuclei and cytoplasm in others. The expression of PPAR gamma protein is decreased in esophageal cancer tissue compared with normal esophageal squamous epithelium. However, we could not deduce the apparent relation for the expression between PPAR gamma mRNA and PPAR gamma proteins in immunohistochemistry (P = 0.284).

CONCLUSIONS

In esophageal cancer tissues, the expression of PPAR gamma was decreased compared with normal esophageal epithelium. The mRNA expression level of PPAR gamma may be a marker of prognosis after operation in esophageal cancer patients.

Expression of PTTG (pituitary tumor transforming gene) in esophageal cancer

BACKGROUND

Recently, a vertebrate securin [pituitary tumor transforming gene (PTTG) in humans] has been identified that inhibits sister chromatid separation and is involved in malignant transformation and tumorigenesis. Abundance of this protein would disrupt cell division, generate chromosomal instability and thereby increase cell susceptibility to acquisition of further mutations during subsequent division. Esophageal cancer is a disease with poor prognosis with early local invasion and lymph node metastasis. It is important to identify factors that influence the aggressiveness of esophageal cancer.

METHODS

Expression of PTTG messenger ribonucleic acid (mRNA) was evaluated by real-time reverse transcription polymerase chain reaction in 48 esophageal cancer specimens and matched normal esophageal mucosa. The data were analyzed with reference to clinicopathological factors.

RESULTS

Tumor tissue expressed a significantly higher level of PTTG1 mRNA than the corresponding normal tissue (P < 0.0001). PTTG1 mRNA expression was significantly higher in tumors with higher pathological stage (IV vs 0-III, P = 0.0442) or more extensive lymph node metastasis (pathological N factor; N4 vs N0-3, P = 0.003). The median survival for patients with high PTTG1 expression (8.5 months) was less than that for patients with low PTTG1 expression (14.0 months, P = 0.039). PTTG1 expression was one of the significant predictors of survival on univariate analysis (hazard ratio 2.225; 95% confidence interval 1.007-4.915).

CONCLUSIONS

Detection of high PTTG1 expression in surgically excised esophagus tumor tissues might help to identify patients with aggressive disease who require adjuvant therapy and provide prognostic information.