Immunohistochemical study of nuclear factor-κB expression in esophageal squamous cell carcinoma: prognostic significance and sensitivity to treatment with 5-FU

Nuclear factor-κB (NF-κB) is expressed in many types of cancers. It has been suggested that the expression of NF-κB is associated with poor prognosis and resistance to chemoradiation therapies. This study evaluated the relationship between the expression of NF-κB and the prognosis and sensitivity of esophageal squamous cell carcinoma (ESCC) to chemotherapy. One hundred and nine ESCC specimens, from patients who had undergone radical esophagectomy, were divided into two groups depending on the expression of NF-κB. Surgical data and prognosis were compared between the two groups. NF-κB-positive tumors were detected in 61.5% of the cases. In 69 patients with stage II and III disease, 41 patients who were NF-κB-positive showed poor survival. The sensitivity of esophageal squamous cell carcinoma cell lines to 5-fluorouracil (5-FU) was analyzed by their NF-κB expression, and the effect of 5-FU was evaluated on the proliferation and activity of two cell lines of cultured ESCCs expressing NF-κB. ESCCs with activated NF-κB had poor sensitivity to 5-FU. These results suggest that the increased expression of NF-κB is associated with poor prognosis in patients with ESCC. NF-κB may be a target for ESCC therapy because of its selective expression in this type of cancer.

Inverse correlation between NKG2D expression on CD8+ T cells and the frequency of CD4+CD25+ regulatory T cells in patients with esophageal cancer

Although malignant diseases are known to be associated with immune suppression, detailed mechanisms of this phenomenon are still unknown. NKG2D is an activating cell surface receptor expressed by natural killer (NK) cells and CD8+ T cells, and it has been reported that NKG2D engagement is extremely important for T cell activation. In the current study, NKG2D expression on CD8+ T cells and the frequency of CD4+ CD25+ regulatory T (Treg) cells were determined by multicolor flow cytometry to investigate one of the mechanisms responsible for immune evasion in esophageal cancer patients. NKG2D expression on CD8+ T lymphocytes in esophageal cancer patients was significantly lower than in those of normal controls. NKG2D expression in T3/T4 esophageal cancer was significantly lower than that in T1/T2 esophageal cancer. CD8+ T cells from patients with lymph node metastasis expressed significantly lower NKG2D than those without lymph node metastasis. Moreover, significantly lower NKG2D expression was observed in stage III/IV cancer in comparison with stage I/II. The frequency of CD4+CD25+ Treg cells in esophageal cancer patients was significantly higher than those in normal controls. NKG2D expression on CD8+ T cells was significantly inversely correlated with the frequency of CD4+CD25+ Treg cells in esophageal cancer patients. Our data indicates that decreased NKG2D expression on CD8+ T cells is correlated with disease severity. Decreased NKG2D expression and an increase in Treg cells may be one of the key mechanisms responsible for immune evasion in esophageal cancer.

Tumor progression and chemoradiosensitivity in relation to the expression of apoptosis related proteins in esophageal squamous cell carcinoma

4588

To study apoptosis related protein expression and their impact on patient’s survival time and sensitivity to postoperative chemoradiotherapy (CRT), we examined the expression of RB, mutant p53, MDM2 and Bax proteins using immunohistochemistry in 115 (CRT; 42) surgically resected esophageal squamous cell carcinoma (ESCC). We also investigated the survivin mRNA expression with quantitative analysis by real-time RT-PCR in 57 (CRT; 30) patients with ESCC. CRT contained 40–60 Gy radiation and continuous infusion of 5-FU (300mg/sqm, day1–5qw). Expression of RB, mutant p53, MDM2, Bax proteins and survivin mRNA were detected in 65%, 46%, 33%, 37% and 32% of patients, respectively. Patients with RB(+), MDM2(-), Bax(+) or survivin(-) tumor had significantly better survival rates than those with RB(-), MDM2(+), Bax(-) or survivin(+) tumor, respectively. However, there was no significant difference in survival between patients with and without mutant p53 expression. In patients not treated with CRT, those with RB(+) or survivin(-) tumor survived significantly longer than those with RB(-) or survivin(+) tumor, respectively. In patients treated with CRT, the expression of Bax protein and survivin mRNA was prognostic indicator. The 5-year survival rates of patients with Bax(+) and survivin(-) tumors were 65% and 39%, significantly superior to 21% and 0% of those with Bax(-) and survivin(+) tumors (P<0.05 and P<0.01, respectively). These results indicate that the expression levels of apoptosis related proteins are important for predicting the prognosis of ESCC patients. Furthermore, CRT may be effective in patients with Bax(+) or survivin(-) tumors. Further investigations are required for clarifying the relationship between the efficacy of postoperative CRT and apoptosis promoting status of ESCC.

No significant financial relationships to disclose.

Phase III randomized controlled trial of hypotonic intraperitoneal cisplatin combined with oral UFT/PSK for the adjuvant treatment of gastric cancer invading the serosa

4027

Background: Peritoneal seeding is the most common pattern of recurrence in patients with gastric cancer invading the serosa who underwent curative gastrectomy. We developed hypotonic intraperitoneal cisplatin for preventing peritoneal recurrence in experimental models. Hypotonic cisplatin had a significant tumorcidal effect in vitro and in vivo. Hypotonic intraperitoneal cisplatin was tolerable in phase I clinical study. Now, we investigated the efficacy of the treatment in a multicenter prospective randomized controlled trial. Methods: 134 pts treated with curative resection for gastric cancer invading the serosa were randomized during surgery to one of 2 treatment arms. As per protocol, eligibility was confirmed by pathology and treatment course in 108 pts as follows: A -Hypotonic intraperitoneal cisplatin (100mg/m2) during surgery and systemic UFT (300mg/day) + PSK (protein-bound polysaccharide, 3g/day) (n=54) and B-Systemic UFT + PSK (n=48). Cisplatin diluted in 1,000 ml of warmed distilled water was injected to the abdominal cavity before closure of the abdomen. Drains were closed for 1 hour after injection of cisplatin. Results: Median follow up was 6.8 years. Postoperative complication rate and side effects were 21.3% and 30.8% in A-arm and 22.4% and 24.0% in B-arm. Tolerance was good in both arms. Peritoneal recurrence rate was 26.9% in A-arm and 40.0% in B-arm (chi-square p=0.16). Overall survival at 5 years was 62.0% and 31.0% in pts with or without hypotonic intraperitoneal cisplatin (log-rank p=0.03). Conclusions: Combining hypotonic intraperitoneal cisplatin and systemic oral chemotherapy improves the efficacy of oral chemotherapy after curative surgery for gastric cancer invading the serosa.

No significant financial relationships to disclose.

The gene expression level of transforming growth factor-beta (TGF-beta) as a biological prognostic marker of hepatocellular carcinoma

The question that transforming growth factor-beta (TGF-beta) provides a tumor-suppressive or a tumor promoting role is still unknown in hepatocellular carcinoma (HCC). In the present study, we quantitatively investigated the gene expression levels of TGF-beta in liver tissues from patients with HCC. We also evaluated the prognostic importance of TGF-beta gene in HCC patients. A total of 59 patients with primary HCC who underwent hepatectomy between 1993 and 2001 were enrolled. TGF-beta gene expression levels of tumors and of noncancerous livers were analyzed by real-time reverse transcriptase polymerase chain reaction (RT-PCR). The percentage of apoptotic cells in tumor cells (apoptotic index: AI) was evaluated with immunohistochemistry. Also the expression of survivin protein (apoptosis inhibitor) in tumors was detected by immunohistochemistry. TGF-beta gene expression levels of tumors were compared with clinicopathological findings of patients. The relative expression level of TGF-beta mRNA of 59 tumor tissues did not differ from those of 8 normal liver tissues or 59 noncancerous liver tissues. The mean AI of 29 tumors with normal expression levels of TGF-beta gene (4%) was significantly higher than that of 30 tumors with low expression levels of TGF-beta gene (2.5%, p = 0.03). Thirteen out of 30 tumors (43%) with low expression level of TGF-P gene showed survivin positive, while only 4 out of 29 tumors (14%) with preserved expression of TGF-beta gene showed survivin positive. This difference was significant (p = 0.012). The overall 5-year survival rate of 29 patients with tumors with preserved TGF-beta gene prolonged to 72% compared with that of 30 patients who had tumors with suppressed TGF-beta gene (58%, p = 0.156). In HCC, TGF-beta gene may play a defensive role against tumor progression by regulating survivin protein expression and by controlling occurrence of spontaneous apoptosis in tumors.

CD8+ lymphocyte infiltration and apoptosis in hepatocellular carcinoma

AIMS

Tumour-infiltrating lymphocytes (TILs) play a role in local anti-tumour immunity. Tumour cells may escape from immune surveillance by expressing RCAS1, a receptor-binding cancer antigen expressed on SiSo cells, which inhibits T cell growth. In this study, the correlation between the density of CD8+ TILs, tumour cell apoptosis, and tumour RCAS1 expression was investigated in hepatocellular carcinoma (HCC).

METHODS

We obtained tissues from 60 patients with surgically resected HCCs. CD8+ TILS, apoptotic cancer cells, and RCAS1 expressing cancer cells were identified by immunohistochemistry.

RESULTS

The density of CD8+ T cells in tumours (mean: 9.5/HPF, HPF: high power field) was significantly less than in non-cancerous hepatic lobules (17.8/HPF, p<0.001) and in relation to the progression of tumour stage. The density of CD8+ T cells in tumours positively correlated with the occurrence of tumour cell apoptosis, but did not correlate with RCAS1 protein expression.

CONCLUSIONS

CD8+ TILs may play a role in the occurrence of tumour cell apoptosis in HCC, but CD8+ TILs may not be controlled by RCAS1 in HCC.

Heparanase gene expression and its correlation with spontaneous apoptosis in hepatocytes of cirrhotic liver and carcinoma

Heparanase (hep) degrades heparan sulphate proteoglycans (HSPGs), which are the main components of the extracellular matrix. This process has been considered as the first step of tumour invasion or metastasis. However, HSPGs play an important role in signal transduction. Thus, the degradation of HSPGs by hep may suppress tumour cell growth. In the present study, we investigated the clinicopathological importance of enhanced hep mRNA expression in 48 hepatocellular carcinomas (HCCs) and in 48 non-cancerous liver samples obtained from the same patients by quantitative real-time reverse transcriptase polymerase chain reaction (RT-PCR). Spontaneous apoptosis in the hepatocytes was evaluated by immunohistochemistry. The relative hep mRNA expression levels were described as hep/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) ratios. The hep mRNA levels of HCCs were significantly lower than those of non-cancerous livers (P<0.001). Hep mRNA levels decreased with increasing liver fibrosis. A significant positive correlation between hep gene expression and spontaneous apoptosis was detected. Hep expression in the tumours did not correlate with tumour differentiation or with tumour stage. However, low hep gene expression was associated with a poor disease-free survival of the patients. Thus, hep gene expression may play an important role in programmed cell death and this gene expression may be lost during the malignant transformation of hepatocytes.

survivin messenger RNA expression is a good prognostic biomarker for oesophageal carcinoma

Oesophageal squamous cell carcinoma is one of the most malignant tumours. To identify patients with a high risk of recurrence of oesophageal squamous cell carcinoma, we investigated the prognostic significance of survivin mRNA expression in oesophageal squamous cell carcinoma, which has recently been reported to be a good marker for unfavourable prognosis in various tumours. Tumours and non-cancerous epitheliums adjacent to tumours were obtained by surgical resection from 57 patients with oesophageal squamous cell carcinoma. Expression levels of survivin and glyceraldehyde-3-phosphate dehydrogenase mRNA were analysed quantitatively by real-time reverse transcriptase polymerase chain reaction (RT-PCR). The survivin/glyceraldehyde-3-phosphate dehydrogenase ratios of tumours were higher than those of non-cancerous tissues (P=0.0003). Tumour-survivin/glyceraldehyde-3-phosphate dehydrogenase ratio did not correlate with histologic type, lymph node metastasis, and stage of tumours. In 53 surviving patients, the 5-year survival rate of 17 patients with high survivin mRNA expressed oesophageal squamous cell carcinoma (14.1%) was significantly poorer than that of 36 with low survivin mRNA expressed oesophageal squamous cell carcinoma (46.8%, P=0.0018). In these patients, tumour-survivin mRNA expression was recognised as a good marker of cancer recurrence independently from tumour stage. These findings indicate that survivin mRNA expression in oesophageal squamous cell carcinoma may be a good biomarker for identifying patients with high risk of cancer recurrence.

Combined resection of invaded organs in patients with T4 gastric carcinoma

BACKGROUND

To understand the efficacy of gastrectomy combined with the resection of other organs and to refine the indications for this type of surgery, the records of 156 patients with carcinoma of the stomach directly invading adjacent organs or structures (T4 gastric carcinoma) were analyzed retrospectively.

METHODS

The patients were divided into three groups, as follows: in group A, curative resection was performed by the combined resection of invaded organs or structures; in group B, although combined resection was performed, curative resection could not be performed because of the extent of lymph node metastasis, liver metastasis, and/or peritoneal metastasis; in group C, combined resection was not performed.

RESULTS

In patients with peritoneal or liver metastasis, there was no significant difference in prognosis among the three groups. In patients without peritoneal and liver metastasis, the prognosis of group A was significantly better than that of group B or group C, irrespective of the extent of lymph node metastasis or the number of invaded organs. In these group A patients, the 5-year survival rates of those with localized tumors and no lymph node metastasis, those with localized tumors and lymph node metastasis, those with infiltrating tumors and no lymph node metastasis, and those with infiltrating tumors and lymph node metastasis were 100%, 56.2%, 57.1%, and 13.6%, respectively.

CONCLUSIONS

Combined resection of involved organs should be carried out with curative intent in patients with localized gastric cancer or infiltrating gastric cancer without lymph node metastasis.

Clinicopathological findings in patients with gastric adenocarcinoma with familial aggregation

BACKGROUND/AIMS

The clinicopathological characteristics of gastric cancer (GC) with a positive family history of site-specific GC have not been well discussed. The aim of this study was to estimate the risk of familial aggregation of GC in a hospital-based case-control study and to analyze the clinicopathological characteristics of GC with familial aggregation of GC.

METHODS

Our series was comprised of 926 histologically confirmed patients with GC (588 males and 338 females) and 2,052 non-cancer outpatients between 1985 and 1996. The odds ratios (ORs), as estimators of relative risks, together with the corresponding 95% confidence intervals (CIs) for a family history of GC and for a family history of other cancers were calculated. Moreover, the clinicopathological findings of patients with GC who had a GC family history were compared with those of patients with GC who had no GC family history.

RESULTS

A positive family history of GC was associated with a statistically significant increase in the risk of GC (OR = 2.15; 95% CI = 1.77-2.63), while no association was observed between the risk of GC and a family history of other cancers (OR = 1.11; 95% CI = 0.91-1.36). The incidence of a multifocal occurrence of GCs was higher in patients with a family history of GC (19.4%) than in patients without a family history of GC (12%, p = 0.005). The risk (OR) of occurrence of multiple cancers in the stomach in patients who had a family history of GC was 1.77 (95% CI = 1.19-2.64).

CONCLUSIONS

Our results suggest that a family history of GC seemed to be a risk factor for the development of GC. Further, a family history of GC was found to be associated with a multifocal occurrence of GC.

Re-expression of the cadherin-catenin complex in lymph nodes with metastasis in advanced gastric cancer: the relationship with patient survival

The cadherin-catenin complex has been recognized as an important factor associated with tumor metastasis. However, the clinical significance of the expression of adhesion molecules in lymph nodes with metastasis remains unclear. The aim of this study was to investigate the clinical significance of the re-expression of the cadherin-catenin complex in metastatic lymph nodes in patients with advanced gastric cancer. Immunohistochemical expression of E-cadherin, alpha- and beta-catenin were analyzed in 96 primary gastric cancers with serosal invasion and in 79 lymph nodes with metastasis. The expression levels of these adhesion molecules in primary tumors and lymph nodes with metastasis were compared. Ninety-four out of 96 primary tumors (98%) showed reduced expression of adhesion molecules. Out of 79 cases with lymph node metastasis, increased expression of one or more adhesion molecules in metastatic foci as compared with primary tumors was detected in 52 cases (66%). Re-expression of adhesion molecules in metastatic lymph nodes was detected in a more advanced stage. The overall 5-year survival rate of the 52 patients who had lymph nodes with metastasis with re-expression of adhesion molecules (8%) was significantly poorer than that of the 27 who had lymph nodes with metastasis without re-expression of adhesion molecules (33%, P = 0.0012). The re-expression of the cadherin-catenin complex in lymph nodes with metastasis may play an important role in the growth of cancer cells in metastatic foci. A comparison of the expression patterns of adhesion molecules between the primary tumor and metastatic lymph nodes may provide new prognostic information for patients with advanced gastric cancer.

Correlation between cathepsin D expression and p53 protein nuclear accumulation in oesophageal squamous cell carcinoma

AIM

The lysosomal protease cathepsin D has been reported to be associated with tumour progression in malignant tumours. Expression of the gene encoding cathepsin D is known to be stimulated by oestrogen in mammary cancer cells. Recent experiments revealed that a p53 DNA binding site is located in the promoter region of the cathepsin D gene. This fact indicates that cathepsin D expression may correlate with p53 protein expression. The purpose of this study is to evaluate the expression patterns of the cathepsin D and p53 proteins in oesophageal squamous cell carcinoma (SCC).

METHODS

In 154 patients with oesophageal SCC, expression of the cathepsin D and p53 proteins was measured in tumours by means of immunohistochemistry using monoclonal antibodies against cathepsin D (clone, 1C11) and p53 (clone, BP53-12).

RESULTS

Cathepsin D was detected in tumour cells, although it was not found in normal oesophageal epithelium adjacent to carcinoma. High cathepsin D expression (positive tumour cells > 10%) was detected in 76 of 154 cases (49%) and high p53 nuclear expression (positive tumour cells > 50%) was detected in 70 cases (46%). High cathepsin D expression was significantly associated with invasive tumour growth (p = 0.002), poor prognosis (p = 0.049), and nuclear accumulation of p53 protein (p = 0.001). Overexpression of both p53 and cathepsin D was seen in 45 of the 154 cases (29.2%). In addition, there was a positive correlation between the cathepsin D index (percentage of cathepsin D positive tumour cells) and Ki-67 labelling index (percentage of Ki-67 positive tumour cells) in 154 oesophageal SCCs (rho = 0.257; p = 0.009). However, in multivariate survival analysis, cathepsin D expression by the tumours was not an independent prognostic factor in patients with oesophageal SCC (p = 0.236).

CONCLUSIONS

The expression of cathepsin D by cancer cells may play an important role in the invasive growth of oesophageal SCC. Overexpression of both p53 and cathepsin D was seen frequently in tumours; p53 gene abnormalities may correlate with cathepsin D overexpression in oesophageal SCC.

Expression of survivin mRNA and protein in gastric cancer cell line (MKN-45) during cisplatin treatment

Survivin is a member of the inhibitor of apoptosis protein (IAP) family. Survivin has been reported to be expressed in many cancers, but not in differentiated normal tissue. Recent studies revealed that survivin correlated with the chemo-resitance of cancer cells. In the present study, the changes in expression levels of survivin messenger RNA (mRNA) and survivin protein in a gastric cancer cell line (MKN-45) during cisplatin (CDDP) treatment were analyzed and compared with the occurrence of apoptotic cell death. Cell growth was inhibited even with a low dose CDDP (0.1 or 1 microg/ml) 1 hr treatment. However, the percentage of apoptotic cells did not change after 48 hr incubation with low dose CDDP. Only with high dose CDDP (10 microg/ml), did the percentage of apoptotic cells explosively increase between 12 and 24 hr treatment. Relative expression levels of survivin mRNA and survivin protein increased after CDDP treatment. The cell expression rates of survivin mRNA after 48 hr treatment with 0.1 and 1 microg/ml of CDDP were 2 to 6 fold higher than that of the survivin mRNA of untreated cells. Also, the relative cell expression level of survivin protein after 24 hr treatment with 0.1 or 1 microg/ml of CDDP was 3 to 6.5 fold higher than that of the survivin protein of untreated cells. These results indicate that survivin expression may correlate with the chemo-resistance of malignant cells.

The expression of thymidine phosphorylase suppresses spontaneous apoptosis of cancer cells in esophageal squamous cell carcinoma

OBJECTIVE

Thymidine phosphorylase (TP) is an enzyme which converts thymidine to thymine. TP is expressed in a variety of human carcinomas and is known to be a potent angiogenic factor. A recent in vitro study indicated that TP is involved in the intracellular apoptotic signal transduction pathway. The aim of this study was to investigate the correlations between the expression of TP, microvessel density (MVD) and the occurrence of spontaneous apoptosis in esophageal squamous cell carcinoma (ESCC).

METHODS

The expression of TP, intratumoral MVDs and percentages of apoptotic cancer cells, expressed by the apoptotic index (AI), of 155 tumors from 155 patients with ESCC were analyzed by immunohistochemistry and compared.

RESULTS

Positive TP expression in cancer and stromal cells was detected in 89 (57.4%) and 104 (67.1%) cases, respectively. The mean MVD and mean AI of the 155 tumors were 288/mm(2) (range: 36-668/mm(2)) and 2.1% (range: 0-20.4%). The mean MVD of 104 tumors with TP-positive stromal cells (336/mm(2)) was higher than that of 51 tumors with TP-negative stromal cells (188/mm(2), p < 0.001). However, the mean MVD of 89 tumors with TP-positive cancer cells (293/mm(2)) did not differ from that of 66 tumors with TP-negative cancer cells (280/mm(2), p = 0.509). On the other hand, the mean AI of 89 tumors with TP-positive cancer cells (1.2%) was lower than that of 66 tumors with TP-negative cancer cells (3.4%, p < 0.001). However, the mean AI of 104 tumors with TP-positive stromal cells (1.9%) did not differ from that of 51 tumors with TP-negative stromal cells (2.6%, p = 0.058). No significant correlation between the MVDs and the AIs was observed (rho = -0.067, p = 0.409).

CONCLUSION

In ESCC, TP may play an important role in tumor progression by increasing microvessels and suppressing apoptosis of cancer cells.

Significant correlation between micrometastasis in the lymph nodes and reduced expression of E-cadherin in early gastric cancer

BACKGROUND

E-cadherin has been recognized as an important factor associated with tumor metastasis. However, the relationship between micrometastasis in the lymph nodes and the expression of E-cadherin in the primary tumor in gastric cancer remains unclear.

METHODS

Two consecutive sections of 4522 lymph nodes from 162 patients with early gastric cancer were prepared for simultaneous hematoxylin and eosin (H&E) and cytokeratin (CK) staining. Sections of primary tumors from 135 of these patients were prepared for E-cadherin immunostaining.

RESULTS

The incidence of lymph node involvement was significantly increased, from 6.8% (11/162 patients) by H&E staining, to 27% (43/162 patients) by CK immunostaining (P < 0.0001). Micrometastasis in the lymph node was found in 32 of 151 (21%) patients who had no lymph node metastasis evidenced by H&E staining. Micro-lymph node metastasis was frequently found in tumors with a diameter more than 1.0 cm, of those that were poorly differentiated, deeply invaded, showed lymphatic on vascular invasion, and in those that showed reduced expression of E-cadherin. Loss of expression of E-cadherin in the primary tumor was closely correlated with micro-lymph node metastasis. Patients with tumors with micro-lymph node metastasis detected by CK immunostaining had a significantly lower 5-year survival rate (P < 0.01) than those without such metastases.

CONCLUSION

Tumors more than 1.0 cm in diameter and those that exhibit poor differentiation, deep invasion (i.e., to the submucosa), lymphatic or vascular invasion, and reduced expression of E-cadherin are risk factors for lymph node metastasis in early gastric cancer. Thus, it is recommended that cancers confined to the mucosa (m-cancers) that are more than 1.0 cm in diameter should not be treated with limited surgery without lymphadenectomy.

Changes in survivin messenger RNA level during cisplatin treatment in gastric cancer

Survivin is a member of the inhibitor of apoptosis protein (IAP) family. The expression of survivin has not been reported in differentiated normal tissues, but it has been observed in many cancerous tissues. Recent studies have revealed that survivin may correlate with the chemo-radio resistance of certain malignant cells. In the present study, the correlation between the occurrence of apoptosis and the level of expression of survivin messenger RNA (mRNA) was investigated in a gastric cancer cell line (MKN-45) and in patients with advanced gastric cancer during cisplatin (CDDP) treatment. In the gastric cancer cell line, the percentage of apoptotic cells (apoptotic index: AI) did not change after 48 h incubation with low-dose CDDP (1 microg/ml), whereas the AI explosively increased between 12 and 24 h treatment with high-dose CDDP (10 microg/ml). Relative levels of expression of survivin mRNA and survivin protein increased after low- and high-dose CDDP treatment. Survivin mRNA was not detected in normal gastric mucosas. Also, in 13 patients with advanced gastric cancer who underwent CDDP-based preoperative chemotherapy, survivin mRNA was detected in only 2 cases (15.4%). Survivin mRNA was observed in the resected tumor specimens of two cases. No significant correlation between survivin mRNA expression and the occurrence of apoptosis in resected tumors or between survivin mRNA expression and patient survival was observed. These findings indicate that survivin may play an important role for the chemoresistance of this cancer cell line. However, the clinical importance of survivin expression remains unclear in patients with gastric cancer.

[Immunohistochemical study of dihydropyrimidine dehydrogenase (DPD) and p53 in biopsied specimens of esophageal cancer before chemoradiotherapy]

We studied whether the immunohistochemical status of dihydropyrimidine dehydrogenase (DPD) and p53 can be used to predict the sensitivity to chemoradiotherapy (CRT) in patients with esophageal cancer. In 19 patients who did not undergo preoperative CRT, the immunoreactivity of DPD and p53 in biopsied specimens correlated well with those in surgically resected specimens (DPD: 100%, p53: 73%). Fifteen patients were treated with 5-FU (250-300 mg/body/day: day 1-5, 8-12), low-dose cisplatin (10 mg/body/day: day 1, 8) and radiotherapy (30-40 Gy). The response rate (CR + PR) for CRT in these patients was 40%. All tumors that showed CR or PR demonstrated low expression of DPD. However, all tumors with high DPD expression showed MR or NC. However, the expression of p53 did not correlate with the response rate for CRT. Therefore, the effect of CRT for esophageal cancer may be predicted by immunohistochemical examination of DPD in biopsied tumor specimens.

Prognostic factors in patients with advanced gastric cancer treated by noncurative resection: a multivariate analysis

BACKGROUND/AIMS

The relationship between prognostic factors and survival time after noncurative gastric resection in patients with advanced gastric cancer was examined by a retrospective review of data on 364 patients.

METHODOLOGY

There were 168 patients without metastasis to the liver or peritoneum (group A), 127 with peritoneal metastasis and no liver metastasis (group B), 50 with liver metastasis and no peritoneal metastasis (group C) and 19 with synchronous liver and peritoneal metastases (group D). Patients were primarily treated with the following 3 drugs: the fluorinated pyrimidines, cisplatin, and mitomycin C.

RESULTS

Patients in group D had a very poor prognosis as compared with the other groups. Multivariate analysis using the Cox's proportional hazard model adjusted for sex, age, and other covariants indicated that lymph node metastasis, lymph node dissection, and fluorinated pyrimidines for group A, cisplatin for group B, and lymph node dissection for group C were independent prognostic factors. An analysis of patients excluding cases who died within 30 days after surgery revealed that lymph node dissection for group A, lymph node dissection and cisplatin for group B, and lymph node dissection for group C were independent prognostic factors.

CONCLUSIONS

Treatment protocol specific for the residual disease may improve the survival of patients with advanced gastric cancer treated by noncurative resection.

Cyclin D1 expression and retinoblastoma gene protein (pRB) expression in esophageal squamous cell carcinoma

PURPOSE

Alterations in the cell cycle regulatory cyclin/retinoblastoma protein (pRB) pathway play a important role in tumor progression in esophageal squamous cell carcinoma (ESCC). In the present study, we evaluated the prognostic significance of the combined analysis of cyclin D1 and pRB in ESCC retrospectively.

METHODS

Immunoreactivities of cyclin D1 and pRB were evaluated in 148 surgically resected ESCC by use of monoclonal antibodies. Disease-free survival of patients was compared among the four subgroups according to the phenotypes of cyclin D1 and pRB expressions.

RESULTS

High immunoreactivities of pRB and cyclin D1 were detected in 64.2% and 40.5% of tumors, respectively. The loss of pRB expression and overexpression of cyclin D1 correlated with short survival. However, these factors were not detected as independently prognostic in multivariate analysis. In 107 surviving patients who underwent curative operation, co-expressed pRB and cyclin D1 (pRB+/cyclin D1 +: 29 patients) were correlated with unfavorable prognosis (disease-free 5-year survival rate: 42.7%) and high cancer recurrence rate (44.8%) compared with that of 40 patients with pRB +/cyclin D1- tumors (70.5% and 27.5%). The disease-free 5-year survival rate of patients with pRB+/cyclin D1- tumors was significantly better than that of other groups (P=0.001). However, the disease-free 5-year survival rate of 29 patients with pRB+/cyclin D1 + tumors was equivalent to that of 29 patients with pRB-/cyclin D1tumors (48.3%), and that of nine patients with pRB-/cyclin D1+ tumors (22.2%, P=0.237).

CONCLUSIONS

Our results suggest that overexpression of cyclin D1 may suppress pRB function, and that combined analysis of pRB and cyclin D1 may be a useful parameter of patient prognosis in ESCC.

Postoperative morbidity and mortality after gastrectomy for gastric carcinoma

BACKGROUND/AIMS

Surgical technique and postoperative care for gastric cancer have significantly improved in recent years. However, whether postoperative morbidity or mortality rates after gastrectomy for gastric cancer were reduced or not in recent years was unclear. In this study, we analyzed the chronological changes of postoperative morbidity and mortality rates, and we analyzed risk factors for postoperative morbidity and mortality in patients undergoing gastrectomy for carcinomas of the stomach.

METHODOLOGY

A total of 887 patients with gastric cancer were gastrectomized in our hospital between January 1985 and December 1996. The patients were divided into three groups on the basis of chronology. The first group included patients treated over the period 1985 to 1988 (n = 324); the second group, 1989 to 1992 (n = 300); and the third group, 1993 to 1996 (n = 263). Postoperative morbidity rates and mortality rates were compared among the three groups. Also, significant risk factors affecting postoperative morbidity and in-hospital mortality were analyzed by the multiple logistic regression analysis.

RESULTS

Postoperative complications were detected in 95 patients (10.7%) and in-hospital mortality rate was 2.4% (21/887). Postoperative morbidity rates were 10.5%, 11%, and 10.6% in the first, second, and third groups, respectively and postoperative mortality rates were 2.5%, 2%, and 2.7%, respectively. These postoperative morbidity and mortality rates were not different between the groups (P = 0.979 and P = 0.866). The most common postoperative complication was anastomotic leakage (56/95, 58.9%). Significant risk factors affecting in-hospital mortality were Stage IV (P = 0.006) and noncurative gastric resection (P = 0.004). However, the extent of lymph node dissection, combined resection, or the existence of preoperative complications were not significant risk factors of in-hospital mortality by multiple logistic regression analysis.

CONCLUSIONS

These results indicate that patients with far-advanced gastric cancer might have a high risk of postoperative mortality. In noncurative operations for patients with advanced gastric cancer, unnecessary lymph node dissection or combined resection should be avoided.

Clinicopathological significance of cathepsin D expression in gastric adenocarcinoma

OBJECTIVE

An estrogen-regulated lysosomal protease, cathepsin D, has been detected in a variety of tissues. This proteinase has been described as closely associated with tumor progression and metastasis in malignant tumors. The purpose of this study was to determine the clinicopathological and prognostic significance of cathepsin D expression in gastric adenocarcinoma.

METHODS

In a consecutive series of 478 patients with gastric carcinoma (median follow-up period: 93 months, range: 1-285 months), cathepsin D expression in tumors was quantitatively analyzed with immunohistochemistry using a monoclonal antibody against cathepsin D (clone: 1C11). The percentage of cathepsin-D-positive cancer cells (the CD index) was calculated. In addition, the amount of cathepsin-D-positive stromal cells was evaluated; three grades (high, intermediate, and low) were used for the classification.

RESULTS

The mean CD index of 478 tumors was 12.8% (range: 0-100%, median: 8%). The mean CD index of diffuse-type gastric carcinomas (14.9%) was significantly higher than that of intestinal-type carcinomas (10.1%, p < 0.0001). Cathepsin D expression of cancer cells was significantly associated with the depth of tumor invasion in both types. The percentage of tumors with high cathepsin D expression in stromal cells was significantly higher in well-differentiated tumors (25.5%) than in moderately differentiated (12.8%) or in poorly differentiated tumors (19.1%). Cathepsin D expression of stromal cells was significantly associated with the depth of tumor invasion in the intestinal type, in contrast to the diffuse type. Highly expressed cathepsin D in cancer cells was associated with a poor prognosis in both types of carcinoma, but in stromal cells highly expressed cathepsin D was associated to a poor prognosis in the intestinal type only.

CONCLUSION

These results indicate that cathepsin D expression in cancer cells may play an important role in tumor progression in diffuse-type gastric carcinoma, whereas in the intestinal type of carcinoma, cathepsin D expression in stromal cells may play an important role in tumor progression.

Thymidine phosphorylase activity in liver tissue and its correlation with multifocal occurrence of hepatocellular carcinomas

BACKGROUND

In hepatocellular carcinoma (HCC), new tumors develop in the residual liver within a few years after hepatectomy. However, the biological risk factors of multifocal occurrence of cancers remains unclear. In this study, the thymidine phosphorylase (TP) activity, which is known as an angiogenic factor, of cancerous and non-cancerous liver tissues in HCC was analyzed to determine its suitability as a biological marker of the multifocal occurrence of HCCs.

MATERIALS AND METHODS

Fresh tissues (tumor: HCC and adjacent liver tissue: N-HCC) from 63 patients with HCC and normal liver tissues (NL) from 6 patients without HCC were obtained. The TP activities of the tissues were analyzed by an enzyme-linked immunosorbent assay (ELISA).

RESULTS

The mean TP activity of 63 HCCs (136 U/mg protein) was higher than that of 63 N-HCCs (81 U/mg protein) and that of 6 NLs (47 U/mg protein, p < 0.001). Multifocal occurrence of HCCs were detected in 17 patients. In these 17 patients, the mean TP activity of HCCs (145 U/mg protein) was not different from that of HCCs from the remaining 46 patients (133 U/mg protein, p = 0.272), however the mean TP activity of N-HCCs (110 U/mg protein) was significantly higher than that of N-HCCs from the remaining 46 patients (71 U/mg protein, p = 0.038). Moreover, only a high TP activity of N-HCCs was detected as a significant risk factor of multifocal occurrence of HCCs.

CONCLUSION

Patients who have tumors with high TP activity in the non-cancerous livers may have a risk of multifocal occurrence of HCCs in the residual liver.

Micro-lymph node metastasis and its correlation with cathepsin D expression in early gastric cancer

BACKGROUND AND OBJECTIVES

Limited operations for early gastric cancer (EGC) have been recommended based on data from lymph node (LN) metastasis detected by hematoxylin and eosin (HE) staining. Recently, the clinical importance of micro-LN metastasis has been reported. In this study, the indication of limited operations for EGC was re-evaluated based on the data from micro-LN metastasis detected by cytokeratin (CK) immunostaining. Also, the correlation between micro-LN metastasis and lysosomal acidic protease cathepsin D (CD) expression in primary tumors was evaluated.

METHODS

A total of 5,949 LNs from 160 patients with EGC were stained by anti-CK monoclonal antibody (CAM 5.2). Also, the 160 primary EGCs were stained by CD.

RESULTS

The incidence of LN metastasis increased from 7.5% (12/160) by HE-staining to 27.5% (44 of 160) by CK immunostaining. The incidence of micro-LN metastasis increased according to the depth of tumor invasion (mucosal cancer: 19% and submucosal cancer: 36.8%) and the size of tumors (< or = 1.0 cm: 5.9%, 1.1-2.0 cm: 25.6%, and > 2.1 cm: 31.7%). The CK-staining patterns were classified into the three subgroups (CK-negative, n = 116; single cell type, n = 27; and clustered type, n = 17). The occurrence of cancer recurrence was significantly higher in clustered type (17.6%) than in single cell type (3.7%) and in CK-negative (0%, P < 0.0001). The mean percentage of CD-positive cancer cells of primary tumors in clustered type (17.2%) was significantly higher than in single cell type (12.3%) and in CK-negative (7.5%, P = 0.0036).

CONCLUSIONS

The acidic protease CD may play an important role of cancer metastasis in EGC. The limited operation without lymphadenectomy should be indicated for EGC with CD-negative.

Clinical significance of E-cadherin-catenin complex expression in metastatic foci of colorectal carcinoma

BACKGROUND AND OBJECTIVES

Reduced expressions of cell adhesion molecules (E-cadherin, alpha-catenin, and beta-catenin) has been reported to be associated with tumor metastasis. However, the clinical significance of such adhesion molecules in the metastatic foci remains unclear. In this study, we evaluated the prognostic significance of E-cadherin, alpha-catenin, and beta-catenin expressions in the metastatic foci of patients with colorectal carcinoma.

METHODS

The expressions of E-cadherin, alpha-catenin, and beta-catenin were detected immunohistochemically in 105 primary tumors, in 30 metastatic lymph nodes, and 13 metastatic liver tumors from consecutive patients with colorectal carcinoma.

RESULTS

Reduced normal expression of E-cadherin, alpha-catenin, and beta-catenin in comparison with normal epithelium was detected in 78 primary tumors, respectively. Patients who had tumors with reduced expression of adhesion molecules showed unfavorable prognosis and the reduced expression of adhesion molecules was detected as one of the independent prognostic factors for patients with colorectal carcinoma. In 30 patients with lymph node metastasis, the increased expression of adhesion molecules in metastatic lymph nodes compared with primary tumors was detected in 13 patients. The prognosis of these 13 patients was poorer than that of remaining 17 patients (P = 0.0296). Also, in 13 patients with liver metastasis, even no significant difference was observed, the mean survival time of 6 patients who had metastatic liver tumors with increased expression of adhesion molecules (10 months) was shorter than that of the remaining 7 patients (16 months; P = 0.1718).

CONCLUSIONS

These results suggest that increased expression of the cadherin-catenin cell-cell adhesion system in metastatic foci may play an important role in progression of metastatic colorectal carcinomas.

Epigenetic heterogeneity at imprinted loci in normal populations

Genomic imprinting is the phenomenon by which the two alleles of certain genes are differentially expressed according to their parental origin. Extensive analysis of allelic expression at multiple imprinted loci in a normal population has not performed so far. In the present study, we examined the allelic expression pattern of three imprinted genes in a panel of 262 Japanese normal individuals. We observed differences in the extent of maintenance of allele-specific expression of the three genes. The allelic expression of small nuclear ribonucleoprotein N (SNRPN) was stringently regulated while that of multimembrane-spanning polyspecific transporter-like gene 1 (IMPT1) showed a large degree of variation. Significant biallelic expression of insulin-like growth factor II (IGF2) was observed in about 10% of normal individuals. Our findings add to the accumulating evidence for variable allelic expression at multiple loci in a normal human population. This epigenetic heterogeneity can be a stable trait and potentially influence individual phenotypes.

Correlation between spontaneous apoptosis and the expression of angiogenic factors in advanced gastric adenocarcinoma

The aim of this study was to investigate whether angiogenic factors influence the occurrence of spontaneous apoptosis in advanced gastric cancer. The apoptotic indices (AIs) of 97 tumors from 97 patients with advanced gastric cancer (pT3, pN0, pM0, Stage II) were analyzed by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end labeling (TUNEL) method. Intratumoral microvessel densities (IMVDs) of tumors stained with anti-CD34 monoclonal antibody were quantified under x 200 magnification using computer-assisted image analysis. The expressions of angiogenic factors, such as vascular endothelial growth factor (VEGF), thymidine phosphorylase (dThdPase), transforming growth factor-alpha (TGF-alpha), and p53 were analyzed immunohistochemically and compared with IMVDs and AIs. The mean IMVD of the 97 tumors was 365/mm2 (range 147-990/mm2). The mean AI of tumors was 2.1% (range 0-11.3%). A significant inverse correlation between the AIs and the IMVDs was shown (p = -0.278, P = 0.0064). The mean IMVDs of tumors with high expressions of dThdPase, TGF-alpha, or p53 were significantly higher than those of tumors with low expressions of these factors. The mean AI of tumors with high expressions of dThdPase was significantly lower than that of tumors with low expressions of dThdPase (P = 0.023). However, no significant correlations were detected between AIs and the expression levels of VEGF, TGF-alpha, or p53. In gastric cancer, dThdPase may play an important role in tumor progression by increasing microvessels and by suppressing apoptosis of cancer cells.

Pharmacokinetics of intraoperative intrapleural cisplatin chemotherapy of various osmolarities in cases of esophageal cancer

Intraoperative intrapleural (i.pl.) cisplatin (CDDP) treatment during thoracotomy was performed for esophageal cancers. Three patients underwent isotonic (308 mOsm/l) CDDP treatment. Hypotonic CDDP treatments with a 154 mOsm/l solution and a 62 mOsm/l solution were administered to 4 and 9 patients, respectively. The maximum concentrations (Cmax) of both total and filterable platinum in the plasma after injection of the hypotonic solution were significantly higher than those after injection of the isotonic solution. The area under the curve of concentration versus time (AUC) of the plasma of the 62 mOsm/l solution was significantly higher than that of the 154 mOsm/l and isotonic solution. Although higher levels of the Cmax may increase side-effects, the hypotonic condition of the i.pl. fluid and increased AUC in the plasma may escalate the accumulation of platinum in i.pl. cancer cells. These results suggest that hypotonic i.pl. CDDP is tolerable and may be useful for treatment of the incipient phase of pleural carcinomatosis and for prophylaxis of postoperative recurrence.

Dihydropyrimidine dehydrogenase activity of cancerous and non-cancerous tissues in liver and large intestine

5-fluorouracil (5-FU) is a widely used chemotherapeutic agent for various carcinomas. However, the therapeutic effect of 5-FU differs among patients. The differences in the effectiveness of 5-FU are thought to be based on the different enzymatic activity which inactivates 5-FU of the host tissue. 5-FU is catabolized to 2-fluoro-beta-alanine by dihydropyrimidine dehydrogenase (DPD) in liver and tumors. In this study, we investigated the clinical significance of detecting DPD activity in patients with hepatocellular and colorectal carcinomas. DPD activity in 63 hepatocellular carcinomas (HCCs), 3 cholangiocellular carcinomas (CCCs), 63 non-cancerous liver tissues adjacent to HCCs (N-HCCs), 6 normal livers (NLs), 189 colorectal carcinomas (CRCs), and 189 non-cancerous colorectal mucosas (N-CRCs) was analyzed by enzyme-linked immunosorbent assay (ELISA). The mean DPD activities of these tissues were 209 +/- 187 Unit (U)/mg protein (HCC), 140 +/- 34 (CCC), 105 +/- 50 (N-HCC), 93 +/- 24 (NL), 58 +/- 45 (CRC), and 83 +/- 92 (N-CRC). DPD activity of HCC was higher than that of CRC (p < 0.0001). DPD activity of N-HCC was higher than that of N-CRC (p < 0.0001). DPD activity of HCC was higher than that of N-HCC (p = 0.0014), on the other hand, DPD activity of CRC was lower than that of N-CRC (p < 0.0001). Tumor DPD activity in HCC and CRC did not correlate with tumor differentiation or progression nor with patient survival. In 20 CRC patients with synchronous liver metastasis, who underwent post-operative 5-FU chemotherapy through the hepatic artery, the mean survival time (29 months) of 9 patients with high DPD was not significantly different from that of 11 patients with low DPD (18 months, p = 0.3412). These findings could provide an explanation for the relative 5-FU resistance of HCC compared with CRC. However, the DPD activities of tumors may not reveal tumor differentiation or progression in HCCs or in CRCs. Moreover, the DPD activity of primary CRC may not be a good indicator of the 5-FU chemosensitivity of synchronous liver metastasis.

Bax expression as a prognostic marker of postoperative chemoradiotherapy for patients with esophageal cancer

Postoperative chemoradiotherapy was introduced to improve the survival of patients with esophageal squamous cell carcinoma (ESCC). However, considerable number of patients still die of cancer recurrence despite curative operation plus chemoradiotherapy. This indicates that some ESCCs are chemoradio-resistant. To prevent unnecessary treatment and to improve the effect of post-operative adjuvant therapy, it seems to be important to investigate biological markers of chemoradio-sensitivity in ESCC. Loss of Bax expression has been reported to be associated with poor response to chemotherapy in breast cancer, and Bax promotes apoptosis in cells. Abnormal expression of Bax may play an important role in chemoradio-sensitivity in malignant tumors. In this study, we retrospectively investigated the prognostic significance of the expressions of Bax and p53 in patients with ESCC. Immunoreactivities of Bax and p53 were evaluated in 141 surgically resected ESCC by using monoclonal antibodies. Prognoses of 141 patients with or without postoperative chemoradiotherapy were compared among groups with high and low expressions of Bax or p53. High immunoreactivities of Bax and p53 were detected in 49 cases (33.1%) and in 70 cases (47.3%), respectively. Loss of Bax expression was detected more frequently in p53-positive tumors. Bax expression correlated with favorable prognosis (P=0.016) in 57 patients with postoperative chemoradiotherapy. However, in 84 patients without adjuvant therapy, the prognostic significance of Bax was minimal. Moreover, in patients with or without postoperative chemoradiotherapy, p53 expression did not correlate with the prognosis. Bax expression may be a good marker for chemoradio-sensitivity in patients with ESCC.

A partially unfolded state of equine beta-lactoglobulin at pH 8.7

The urea-induced unfolding transition of equine beta-lactoglobulin was studied at pH 8.7 using circular dichroism (CD), ultracentrifugation, and gel filtration chromatography. The unfolding transition curves showed that at least one intermediate accumulates at moderate concentrations of urea. Furthermore, analytical ultracentrifugation experiments indicated that the intermediate forms a dimer. Thus, the urea-induced unfolding transition was measured by CD at various protein concentrations and was analyzed by a model assuming the four conformational states (the native, intermediate, dimeric intermediate, and unfolded states). The characteristics of the intermediate are markedly different from those of the intermediate previously observed at pH 4.0 or 1.5. The intermediate at pH 8.7 does not show the intense far-ultraviolet CD suggestive of the nonnative alpha-helix.

Molecular dynamics study on hydrophobic effects in aqueous urea solutions

Hydrophobic effects in aqueous urea were analyzed by molecular dynamics simulations. The contribution of solvents to the potential of mean force between two methane molecules was calculated by using molecular dynamics simulations and was compared with the solubility data of hydrocarbons in aqueous urea. Both the simulation results and the solubility data indicated that urea stabilizes methane-methane association. The stabilization was due to increasing the solvation free energies of small hydrocarbons such as methane by addition of urea. The solvation free energies of larger hydrocarbons, on the other hand, are decreased by addition of urea. This effect of the solute size on hydrophobic free energies in aqueous urea was also analyzed by using molecular dynamics simulations by means of division of the solvation process into two parts: the cavity formation and the introduction of the solute-solvent attractive interactions. In the cavity formation, urea increased hydrophobic free energies, and in the introduction of the solute-solvent attractive interactions, urea decreased hydrophobic free energies. The influence of urea on hydrophobic free energies was determined by the balance of effects of the two parts of the solvation process.

Prediction of survival period for patients with postoperative recurrence after curative resection for advanced gastric carcinoma

BACKGROUND/AIMS

Although many studies have attempted to clarify the prognostic indicators for gastric carcinoma, there have been few studies regarding the factors that correlate with the survival period of patients with postoperative recurrence.

METHODOLOGY

Among 504 advanced gastric adenocarcinoma patients who had undergone curative gastrectomy, 188 patients who had died of recurrence were used in this study.

RESULTS

Univariate analysis indicated that age, the presence of lymph node metastasis and blood vessel invasion, the number of positive lymph nodes, and gastrectomy significantly correlated with the survival period. Multivariate analysis indicated that the length of the survival period was independently influenced by the number of positive lymph nodes and blood vessel invasion. The survival time of patients with less than 3 positive lymph nodes and no accompanying blood vessel invasion was significantly longer than that of other patients.

CONCLUSIONS

The number of positive lymph nodes and the presence of blood vessel invasion are the most important factors predicting the survival period of patients with postoperative recurrence after curative resection for advanced gastric carcinoma.

Mutated p53 in tumors, mutant p53 and p53-specific antibodies in the circulation in patients with gastric cancer

The accumulation of mutated p53 in tumor cells results in the presence in the circulation of mutant p53 (p53m) and the production of p53-specific antibodies (p53Ab). We examined the relationships among these phenomena and analyzed their clinical implications in 62 patients with gastric cancer at various stages. Expression of p53 in tumors was studied by an immunohistochemical method and circulating p53m and p53Ab were quantitated with commercially available enzyme-linked immunosorbent assay kits. The detectable expression of p53 in tumors and circulating p53Ab was recognized in 28 (45.2%) and 7 (11.3%) of the 62 patients, respectively. The number of patients with higher levels of circulating p53m increased with the progression of the depth of cancer invasion. Patients with any positive findings for the three p53-related parameters had a poorer prognosis, and the difference was statistically significant in patients with p53Ab. When survival was analyzed in terms of the combination of the three p53-related parameters (detectable expression of p53 in tumor cells, high levels of p53m and p53Ab in the circulation), a significantly poorer prognosis was associated with an increase in the number of positive parameters. Analysis of p53 in tumor cells, together with analysis of circulating p53m and p53Ab, could improve the accuracy of prognosis in patients with gastric cancer.

Cisplatin combined with prostaglandin E1 chemotherapy in rat peritoneal carcinomatosis

Cisplatin intraperitoneal (i.p.) chemotherapy is frequently performed for patients with peritoneal carcinomatosis. However, cisplatin penetrates only the surface of the peritoneal tumor and has serious side effects on renal cells. Thus, cisplatin i.p. chemotherapy had been limited to use for these patients. Prostaglandin E1 (PGE1) has been used for reducing the toxic effects of anticancer drugs because of its cytoprotective effects and has been reported to enhance tumoricidal activity of anticancer drugs. In our study, the effects of PGE1 on the rat peritoneal carcinomatosis model treated with cisplatin i.p. chemotherapy were evaluated. Cisplatin (5 mg/kg) was given in an i.p. administration to 70 tumor-free rats. PGE1 was administered to 35 rats through the tail vein at an infusion rate of 0.1 microg/kg/min (1 ml/hr), and the remaining 35 rats were injected with physiological saline. Forty rats were given an i.p. injection of 1 x 10(7) AH100B cells. Ten days after injection, cisplatin (5 mg/kg) was administered with PGE1 to 20 and the remaining 20 were injected with physiological saline. The accumulation of platinum in the tissues and apoptotic renal cells were analyzed. The maximum concentrations of platinum in the kidneys of PGE1 untreated rats (tumor-free: 10.11 microg/g; tumor-bearing: 11.45 microg/g) did not differ from those of platinum in the kidneys of PGE1-treated rats (tumor-free: 10.28 microg/g; tumor-bearing: 13.28 microg/g). The number of apoptotic renal cells was significantly reduced by PGE1 administration in both tumor-free and tumor-bearing rats. Moreover, PGE1 increased the maximum platinum concentration in tumor masses (5.31 microg/g) of the treated group compared with that in tumor mass of the control group (2.72 microg/g, p = 0.009). These results indicate that PGE1 may increase the anticancer effect of cisplatin by increasing tumor platinum concentration and may reduce the chance of cisplatin-induced renal failure. Intraperitoneal cisplatin chemotherapy combined with PGE1 treatment may have a therapeutic benefit for patients with peritoneal carcinomatosis.

Limited operation for patients with T1 esophageal cancer

BACKGROUND/AIMS

Transhiatal esophagectomy without thoracotomy has been introduced as a minimally invasive operation to prevent postoperative complications in patients with relatively early-stage esophageal cancer who have preoperative pulmonary or cardiovascular complications or who are in a high age bracket. However, this procedure for patients with esophageal cancer remains controversial, especially as regards curative surgery because complete intrathoracic lymphadenectomy cannot be performed in this operation. Thus, cancer recurrence after this operation has been considered to be high. To evaluate the benefits of this less invasive surgery for patients with T1 esophageal cancer, the prognoses of patients who underwent transhiatal esophagectomy without thoracotomy were compared with those of patients who underwent traditional esophagectomy with thoracotomy.

METHODS

Between 1989 and 1998, 33 patients with T1 esophageal cancer were operated on in our hospital. We introduced transhiatal esophagectomy without thoracotomy in 19 patients who were over 70 years old or who had preoperative complications (transhiatal group). The remaining 14 patients were treated with the transthoracic procedure (transthoracic group). These 33 patients were followed up at our hospital until the end of 1999. The postoperative complications and prognoses in the two groups were compared.

RESULTS

We were able to reduce the operation time using the transhiatal procedure. Even though no significant difference was detected, there were fewer postoperative pulmonary complications with this procedure (11%) than with the transthoracic procedure (21%). The incidences of in-hospital mortality did not differ between the two groups. Cancer recurrence was detected in 5 of 19 patients (26%) in the transhiatal group and in 5 of 14 patients (36%) in the transthoracic group; no difference was observed (P=0.562). The 5-year survival rate (58%) of the transhiatal group was no different from that of the transthoracic group (62%, P=0.69).

CONCLUSIONS

Complete intrathoracic lymphadenectomy cannot be performed along with transhiatal esophagectomy; however, the prognoses of patients who were treated with this procedure were no different from those of patients who were treated with transthoracic esophagectomy. Thus, transhiatal esophagectomy without thoracotomy might be a justifiable operation for compromised patients with T1 esophageal cancer.

An elevated serum level of transforming growth factor-beta 1 (TGF-beta 1) significantly correlated with lymph node metastasis and poor prognosis in patients with gastric carcinoma

BACKGROUND

Overexpression of transforming growth factor beta s (TGF-beta s), multifunctional polypeptides, have been reported in the tissue of various types of carcinomas, including gastric carcinoma. To our knowledge, serum levels of TGF-beta 1 have not previously been examined in patients with gastric carcinoma as a possible indicator of prognosis.

METHODS

Preoperative serum levels of TGF-beta 1 were measured in 111 patients with gastric carcinoma by an enzyme-linked immunosorbent assay.

RESULTS

An elevated level of TGF-beta 1 was significantly correlated with lymph node metastasis and poor prognosis. Moreover, the preoperative serum levels of TGF-beta 1 in patients with peritoneal recurrence were significantly higher than those in patients both with lymph node recurrence and without recurrence.

CONCLUSION

The serum level of TGF-beta 1 might be useful for predicting recurrence patterns and prognosis in patients with gastric carcinoma.

Nuclear profiles of cancer cells reveal the metastatic potential of gastric cancer

Nuclear profiles have been reported as useful prognostic predictors in various cancers. Data from computerized morphometry are objective and can be quickly derived using conventional microscopic analysis, but image analysis of nuclear features has only rarely been applied to investigations of gastric cancer. The aim of this study was to evaluate the correlation between one of these morphological nuclear features and the clinicopathological parameters in patients with gastric cancer. The morphometric nuclear feature (nuclear area) was analysed in 400 patients with gastric cancer. In each case, 300 cancer nuclei on routine haematoxylin and eosin-stained slides were analysed through the use of a computer-assisted image analysis system which traced the nuclear profiles (magnificationx400) on a computer monitor. The morphometric data were compared with the patients' clinicopathological status and survival rate. The mean nuclear area (NA) of cancer cells from 400 cases of gastric cancer was 47.2 microm(2). The NAs of cancer cells from tumours with microvessel invasion (lymphatic or venous invasion), lymph node metastasis or hepatic metastasis at the time of operation were significantly larger than those of cancer cells from tumours without such invasion or metastases. Cytokeratin (CK) immunostaining was performed on 2577 lymph nodes from 91 patients with advanced gastric cancer (pT3, pN0, pM0, stage II) to detect micrometastases. CK-positive lymph nodes were detected in 350 of 2577 lymph nodes (13. 6%) and in 62 of 91 patients (68.1%). The mean NA of cancer cells from 62 tumours with micrometastases (44 microm(2)) was larger than that of cancer cells from 29 tumours without micrometastases (38.8 microm(2), p=0.043), and a significant positive correlation was detected between the NAs of cancer cells from 91 tumours and the number of micrometastatic lymph nodes of 91 patients (rho=0.278, p=0. 008). Cancer cells with large NA correlated strongly with haematogenous and lymph node recurrence or relapse after gastrectomy and the NA of cancer cells was identified as an independent prognostic factor in gastric cancer. Nuclear morphometry is an objective, reproducible, and technically uncomplicated procedure. The NA of cancer cells correlates closely with the metastatic potential of gastric cancer. Nuclear morphometry may therefore be useful for the selection of patients who are at risk of haematogenous or lymph node metastatic recurrence after surgery.