Metastases-related genes in the classification of liver and peritoneal metastasis in human gastric cancer

INTRODUCTION

With the aim of identifying metastases-related genes in gastric cancer, we performed a broad analysis of differential gene expression between low-metastatic parental cell lines and established highly metastatic sublines.

MATERIALS AND METHODS

We established novel cell lines, AZ-H5c, NUGC-3H5, and TMK-1H7, with a high potential of liver metastasis, and AZ-P7a, NUGC-3P4T, and TMK-1P4a, with a high potential of peritoneal metastasis. These cell lines were derived from low-metastatic parental AZ-521, NUGC-3, and TMK-1 cell lines, respectively. Furthermore, to investigate different levels of gene expression implicated in metastatic potentials in gastric cancer, we investigated approximately 2000 expressed genes in each cell line using a DNA microarray.

RESULTS

Varieties of genes were up-regulated or down-regulated in highly metastatic liver and peritoneal cell lines. Fifty-eight genes, including the transferrin receptor, ras-related rho, and osteopontin, and 22 genes, including apolipoprotein E and inhibin A-submit, were up-regulated and down-regulated in two or three liver metastatic sublines. On the other hand, 19 genes, the transferrin receptor, c-fos, and RANTES, and 26 genes, including MAC25, PISSLRE, and RNA polymerase, were up-regulated and down-regulated in two or three peritoneal metastatic sublines.

CONCLUSION

How gene expression is implicated in gastric cancer metastasis has never been thoroughly explained, and further studies are necessary to understand the involvement of genes in cancer metastasis more thoroughly. We hope that our highly metastatic liver and peritoneal experimental models are helpful for further study and gene therapy of human gastric cancer.

Profiling analysis of differential gene expression between hematogenous and peritoneal metastatic sublines of human pancreatic cancer using a DNA chip

We established the novel sublines HPC-1H5, HPC-3H4, HPC-4H4, and Panc-1H5, which have a high potential of liver metastasis, and HPC-1P5a, HPC-3P4a, HPC-4P4a, and Panc-1P5a, which have a high potential of peritoneal dissemination, derived from low metastatic HPC-1, HPC-3, HPC-4, and Panc-1cell lines, respectively. To clarify the molecular mechanisms of cancer metastasis and of the different levels of gene expression in a variety of metastatic potentials in pancreatic cancer, we performed a broad analysis of differential gene expression analysis between parental cell lines and metastatic sublines. In comparison with the parental cell lines, 65 and 36 genes were overexpressed and underexpressed in highly liver-metastatic sublines. On the other hand, 43 and 45 genes were overexpressed and underexpressed in highly peritoneal-metastatic sublines. uPAR and Serin protease were overexpressed, and E2A and IGF1R were underexpressed in both metastatic sublines. Hierarchical clustering analysis revealed 22 genes classifying liver, peritoneal metastatic sublines and low-metastatic parental cell lines. These genes might be targeted genes separating those two major metastatic forms after surgery. A greater number of cell line samples and more genes will have to be utilized in future studies in order to understand the involvement of genes in cancer metastasis more thoroughly. However, these results will help to clarify the molecular mechanisms of pancreatic cancer metastasis.

Metastatic-associated biological properties and differential gene expression profiles in established highly liver and peritoneal metastatic cell lines of human pancreatic cancer

To elucidate metastasis mechanisms, we established a Panc-1H5 subline with a highly liver metastatic cell line and a Panc-1P4a with a highly peritoneal metastatic cell line, which were sequentially selected from the parental pancreatic cancer cell line Panc-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed genes involved in cancer metastasis with a cDNA macroarray. The tumorigenicity, motile activity, adhesive activity and cytokine production of metastatic sublines were higher than those of parental Panc-1 cells. Particularly, in Panc-1H5 cells, adhesive activity to the extracellular matrix and angiogenetic factors increased, whereas in Panc-1P4a cells, motile activity was extremely enhanced compared with Panc-1 cells. Histopathological findings for the three cell lines were the same. In cDNA macroarray analysis of Panc-1H5 cells, 11 genes were up-regulated and 20 genes were down-regulated compared with parental Panc-1 cells. In Panc-1P4a cells, 7 genes were up-regulated and 13 genes were down-regulated compared with parental Panc-1 cells. This study provides a demonstration of global gene expression analysis of pancreatic cancer cells with liver and peritoneal metastasis and these results provide new insight into the study of human pancreatic cancer metastasis.

Differential gene expression screening between parental and highly metastatic pancreatic cancer variants using a DNA microarray

To clarify the difference in genes expressed in hematogenous metastasis and peritoneal dissemination, a broad analysis of differential gene expression analysis between parental cell lines and established metastatic sublines was performed. Using an oligonucleotide array (Gene Chip, Affymetrix), approximately 2,000 genes involved in cancer were analyzed for each of the cell lines. HPC-4H4 (highly metastatic lines to the liver) compared with HPC-4 (low metastatic parental lines), in which 20 overexpressed genes and 5 underexpressed genes were recognized. HPC-4P4a (highly metastatic to the peritoneum) compared with HPC-4, in which 12 overexpressed genes and 15 underexpressed genes were also recognized. Analysis of HPC-4H4 and HPC-4P4a showed comparative up-regulation of 20 genes and down-regulation of 13 in the former, HPC-4H4. Further studies are needed to validate our hypothesis that some of the resulting differentially expressed genes might be implicated in the development of metastasis in pancreatic cancer. In conclusion, this genome-wide expression analysis will help to clarify the molecular mechanisms of cancer metastasis and of the different levels of gene expression in a variety of metastatic potentials in pancreatic cancer.

Proximal gastrectomy and jejunal pouch interposition: evaluation of postoperative symptoms and gastrointestinal hormone secretion

Reflux esophagitis, dumping syndrome and malnutrition are included in the postgastrectomy complications. To prevent or minimize such sequelae, proximal gastrectomy with an interposed jejunal pouch has been advocated as an organ-preserving surgical strategy to improve quality of life for the patients. Proximal gastrectomy was performed in 44 patients with tumors in the upper third of the stomach; 21 had reconstruction using jejunal pouch interposition between the esophagus and the remnant stomach (JP group), while 23 had reconstruction by esophagogastrostomy (EG group). Re-construction method was selected by each patient on the basis of the informed consent. Thirty-five patients had early gastric cancer. Postoperative courses of patients were reviewed in terms of symptoms, weight maintenance, nutritional status, blood chemistry values, endoscopic findings, and radiographic appearances after a barium meal. Concentrations of gastrointestinal hormones were measured in response to a test meal. The JP procedure permitted increased dietary volume. The JP group showed fewer severe postoperative symptoms than the EG group. After operation, all patients examined in both groups showed hypergastrinemia and all patients examined in the JP group showed hypersecretinemia. In proximal gastrectomy, the JP procedure improved patient's post-operative quality of life.

A novel experimental mouse model of peritoneal dissemination of human gastric cancer cells: analysis of the mechanism of peritoneal dissemination using cDNA macroarrays

We established a new cell line, NUGC-3P4T, with high peritoneal metastatic disseminating potential in nude mice. NUGC-3P4T cells were derived from the human gastric carcinoma line NUGC-3, which has low capacity for peritoneal dissemination. NUGC-3P4T cells developed peritoneal dissemination in 10 / 10 (100%) mice, whereas the parental NUGC-3 cells developed dissemination in 1 / 5 (20.0%) mice. The metastatic foci in the peritoneum showed essentially the same histological appearance as those induced by parental cells. The tumorigenicity, the motile activity and the adhesive activity to the laminin of NUGC-3P4T cells were stronger than those of NUGC-3 cells. Production of IL-8 was significantly higher in NUGC-3P4T than in NUGC-3. cDNA macroarrays analysis showed that a variety of cytokines, interleukins, and other immunomodulators and their receptors were up- or down-regulated at the mRNA level in NUGC-3P4T cells, compared with NUGC-3 cells. Thus, this unique cell line and in vivo model might be useful to study the biology of peritoneal dissemination of human gastric cancer.

A new peritoneal dissemination model established from the human pancreatic cancer cell line

We established a new cell line, HPC-3P4a, with high peritoneal disseminated potential in nude mice. HPC-3P4a was derived from a human pancreatic carcinoma cell line (HPC-3) that had low capacity for peritoneal dissemination. HPC-3P4a developed peritoneal dissemination in 10 of 11 (90.9%) cases, whereas parental HPC-3 developed peritoneal dissemination in one of six (16.7%) cases. The metastatic foci in the peritoneum showed essentially the same histologic appearance of parental involvement. The tumorigenicity, motility, and adhesive activity of HPC-3P4a to the extracellular matrix were stronger than were those of the HPC-3. In FACS analysis, HPC-3P4a significantly increased the expression of alpha6 and alpha(v)beta5 integrins, while it decreased alpha2 integrin, hCD44H, and hCD44v 10, as compared with HPC-3. The VEGF production of HPC-3P4a was significantly lower than that of HPC-3. Analysis of gene macroarrays showed a variety of cytokines, interleukin, and other immunomodulatory, and their receptors were up-regulated and down-regulated on an mRNA level in HPC-3P4a cells, compared with HPC-3 cells. Intrasplenic injection of HPC-3P4a produced no liver metastasis. We named our original highly liver metastatic cell line HPC-3H4 (previously reported). This HPC-3H4 cell was established by repeated intrasplenic injection from parental cell HPC-3; thus, it developed high liver metastasis. Moreover, HPC-3H4 developed peritoneal dissemination by intra-abdominal injection. In contrast, HPC-3P4a did not develop liver metastasis by intrasplenic injection. These findings are very interesting and might suggest that the process of hematogenous metastasis differed from that of peritoneal dissemination. Thus, this cell line may be useful for investigating the mechanism of peritoneal dissemination in human pancreatic cancer.

Epstein-Barr virus-associated gastric cancer in a patient with dermatomyositis

A 59-year-old man was admitted presenting systemic rash and muscle weakness. He was diagnosed to have dermatomyositis and a check was made for internal malignancy. Gastrointestinal endoscopy revealed a Borrmann type II tumor on the middle body of the stomach. Biopsy specimens showed a well differentiated adenocarcinoma, and total gastrectomy was performed. The final diagnosis was moderately differentiated adenocarcinoma invading into the proper muscular layer, with metastases to regional lymph nodes. Most of the neoplastic cells were shown to be positive for Epstein-Barr virus by means of EBV-encoded RNA in situ hybridization. The symptoms of dermatomyositis disappeared completely after surgery.

Liver metastatic model for human gastric cancer established by orthotopic tumor cell implantation

We have established an orthotopic implantation model that is highly metastatic to the liver. A human gastric carcinoma cell line, AZ521, with low capacity for liver metastasis was implanted as a single-cell suspension in the stomach of nude mice. The tumor cells derived from a few liver metastatic foci were subsequently implanted orthotopically, and we established a cell line, AZH5G, by repeating the in vivo stepwise selection method. This metastasizing line (AZH5G) developed liver metastasis in seven of eight (87.5%) cases, whereas parental AZ521 developed in 3 of 20 (15.0%). The in vitro growth activities of AZH5G were lower than that of AZ521, although the in vivo tumorigenicity of AZH5G was clearly higher than that of AZ521. Motility assays demonstrated higher motility of AZH5G than of AZ521. Flow cytometric analysis demonstrated that the expression of alpha 6-integrin significantly decreased in AZH5G (4.9% +/- 4.1%) compared to in AZ521 (17.7% +/- 8.1%) (p < 0.05). The adhesive activity of AZH5G cells to laminin was lower than that of AZ521 cells. In contrast, the adhesive activity of AZH5G cells to fibronectin was clearly higher than that of AZ521 cells. These findings suggested that changes in the expression of integrins on the cell surface might play an important role in metastatic ability. This well characterized line and its in vivo experimental model should be useful to investigate the mechanisms of liver metastasis and to develop a new therapeutic approach for human gastric cancer.

Helicobacter pylori infection: augmentation of telomerase activity in cancer and noncancerous tissues

Telomerase adds hexameric repeats of 5'-TTAGGG-3' to the ends of chromosomal DNA (telomere) and has been implicated in cell immortalization and cellular senescence. The aim of this study was to measure quantitatively the telomerase activity and human telomerase RNA component (hTR) content in gastric cancer and to examine the relation between these values and histologic factors including Helicobacter pylori as a risk factor for gastric cancer. Telomerase activity was measured by a modified telomeric repeat amplification protocol in cancerous and noncancerous tissues (intestinal metaplasia, chronic gastritis, normal mucosa) from 27 gastric cancer patients; hTR expression was examined by the quantitative reverse transcriptase-polymerase chain reaction using fluorescent probes. Telomerase activity was higher in cancers (total product generated: 33.7) than in noncancerous tissues. Telomerase activity was higher in intestinal metaplasia (16.7) and chronic gastritis (10.6) than in normal mucosa (3.5). In patients with intestinal-type gastric cancer, telomerase activity was higher in intestinal metaplasia with H. pylori infection than in that without infection. hTR expression was not correlated with telomerase activity. H. pylori infection may influence telomerase activity in cancer and noncancerous tissues.

A novel experimental mouse model of peritoneal dissemination of human gastric cancer cells: different mechanisms in peritoneal dissemination and hematogenous metastasis

We established a new cell line, AZ-P7a, with high peritoneal-metastatic potential in nude mice. AZ-P7a cells were derived from the human gastric carcinoma line AZ-521, which has low capacity for peritoneal dissemination. AZ-P7a cells developed peritoneal metastasis in 11 / 14 (78.6%) mice, whereas the parental AZ-521 cells developed metastasis in 2 / 6 (33.3%) mice. The metastatic foci in the peritoneum showed essentially the same histological appearance as those induced by parental cells. The tumorigenicity and the motile activity of AZ-P7a cells were stronger than those of the parental AZ-521 cells; in contrast, adhesion to the extracellular matrix and the production of vascular endothelial growth factor by AZ-P7a cells were decreased. In fluorescence-activated cell sorter (FACS) analysis, AZ-P7a cells expressed significantly greater levels of integrins alpha2, alpha3, alpha5, alpha6 and alphavbeta5, as compared with AZ-521 cells. However, alpha1, alpha4, alphavbeta3, hCD44H, hCD44v3, hCD44v6 and hCD44v10 were not expressed in either cell line. AZ-P7a cells developed no liver metastasis when administered by the intrasplenic injection method, though the highly liver metastatic cell line AZ-H5c showed the same rate of peritoneal dissemination as that exhibited by AZ-P7a cells after intraabdominal injection. These findings suggested that the mechanism of peritoneal dissemination differed from that of hematogenous metastasis. Moreover, the latter appears to be controlled by more complex mechanisms than the former. Thus, this cell line might be useful for investigating the mechanism of peritoneal dissemination of human gastric cancer.

Establishment and characterization of a human gastric carcinoma cell line that is highly metastatic to lymph nodes

The actual mechanisms by which carcinoma cells metastasize to lymph nodes are still unclear, and there is a need to establish in vivo experimental models suitable for the investigation of lymph node metastasis. For the purpose, we established a highly lymph node-metastasizing line, designated AZL5G, derived from a human gastric cancer cell line, AZ521, which had low capacity for lymph node metastasis. AZL5G cells transplanted orthotopically in the nude mouse stomach metastasize predominantly to the regional lymph nodes, showing little potential for hematogenous metastasis. AZL5G tumors developing in the stomach and regional lymph nodes showed poorly differentiated adenocarcinoma with medullary growth, and their histologic appearance strongly resembled that of parental AZ521. The growth activities in vitro of low-metastatic AZ521 and high-metastatic AZL5G were almost the same, but the tumorigenicity in vivo of AZL5G was significantly higher than that of AZ521. AZL5G cells also showed clearly higher abilities of cell locomotion and adhesion to type IV collagen and fibronectin in vitro as compared with AZ521 cells. Flow cytometric analysis demonstrated that the expression of integrin beta1 subfamily except for alpha6 integrin was generally increased in AZL5G cells than in AZ521 cells. Especially, the expression of alpha1 and alpha2 integrins in AZL5G cells was clearly higher than in AZ521, while alpha(v)beta3 integrin, E-cadherin, ICAM-1 and CD44H were not expressed by either cell line. The cell adhesion blocking assay showed that DGEA-containing peptide, which is composed of alpha2 integrin recognition sequence, significantly reduced the adhesiveness of AZL5G cells to type IV collagen as well as to type I collagen and laminin. Furthermore, the administration of anti-alpha2 integrin mAb or DGEA peptide in AZL5G-transplanted nude mice produced a significant reduction in the number of lymph node metastases. These data suggest that the up-regulation of alpha2 integrin expression by gastric cancer cells may play a critical role in the process of lymph node metastasis through the increased adhesiveness to type IV collagen. In conclusion, we established a gastric cancer cell line, AZL5G, with a highly metastatic potential to lymph nodes. This well-characterized line and its in vivo experimental model should be useful for investigation of the mechanisms of lymph node metastasis and for establishment of a new therapeutic approach for human gastric cancer.

Nitric oxide induces a decrease in the mitochondrial membrane potential of peripheral blood lymphocytes, especially in natural killer cells

Increased levels of nitric oxide (NO) at an inflammatory site may affect the biological activity of lymphoid cells. To investigate the effects of NO on the immune system, we measured the mitochondrial membrane potential (delta psi m) of the peripheral blood lymphocytes (PBL) cultured with a chemical NO donor. PBL from healthy volunteers were cultured with NOC18, a NO-generating compound, at various concentrations. The delta psi m of the PBL was measured by flow-cytometry using 3,3-dihexyloxacarbocyanine iodide (DiOC6(3)). NOC18 induced a decrease in the delta psi m of the PBL in a dose-dependent fashion, induced an increase in the levels of reactive oxygen species (ROS), and caused these cells to undergo apoptosis. Dual-color staining of the delta psi m and lymphocyte surface markers demonstrated that CD3-CD56+ natural killer (NK) cells were responsive to NO. Trolox, a vitamin E analog, partially reversed the NO-induced decrease in the delta psi m of the PBL. We showed that the delta psi m of peripheral NK cells were decreased by NO, which suggests that abundant NO at an inflammatory site may impair NK cell function.

Pharmacokinetic study of S-1, a novel oral fluorouracil antitumor drug

S-1 is a novel oral fluorouracil antitumor drug that combines three pharmacological agents: tegafur (FT), which is a prodrug of 5-fluorouracil (5-FU); 5-chloro-2,4-dihydroxypyridine (CDHP), which inhibits dihydropyrimidine dehydrogenase (DPD) activity; and potassium oxonate (Oxo), which reduces gastrointestinal toxicity. Phase I and early Phase II clinical trials have already been completed. On the basis of the results of these trials, 80 mg/m2/day, given daily in two divided doses after breakfast and supper, a 28-day consecutive oral regimen is recommended. In this study, we investigated the pharmacokinetics of 5-FU, intact FT, CDHP, and Oxo, after administration of S-1, at a standard dose of 80 mg/m2/day, in advanced cancer patients. Twelve patients were recruited to the study; 5 patients with gastric cancer, 4 with colorectal cancer, and 3 with breast cancer. Among them, analysis was conducted on 12 patients for single administration and on 10 patients for consecutive administration. The initial dose of S-1 for each patient was determined according to his/her body surface area (BSA) as follows: for BSA < 1.25 m2, 80 mg/body/day; for 1.25 m2 < or = BSA < 1.5 m2, 100 mg/day; and for 1.5 m2 < or = BSA, 120 mg/day. For single administration, half of the standard dose was used. For 28-day consecutive administration, the standard dose was given daily in two divided doses. The average single dose per BSA was 35.9 mg/m2 (31.7-39.7 mg/m2). Pharmacokinetic parameters of plasma 5-FU were as follows: Cmax, 128.5 +/- 41.5 ng/ml; Tmax, 3.5 +/- 1.7 h; AUC(0-14), 723.9 +/- 272.7 ng x h/ml; and T(1/2), 1.9 +/- 0.4 h. In the 28-day consecutive regimen, there were no fluctuations in pharmacokinetics nor any drug accumulation. Because the pharmacokinetics of orally administered S-1 is almost similar to that of continuous i.v. infusion of 5-FU, we concluded that S-1 may improve patients' quality of life.

A case of partial autotransplantation of the liver in advanced hepatocellular carcinoma

Hepatocellular carcinoma in Japan is frequently complicated by chronic hepatic disease such as chronic hepatitis and liver cirrhosis, and it is often impossible to decide the range to be resected only based on clinical stage and other tumor factors. We experienced a case with advanced hepatocellular carcinoma complicated by liver cirrhosis that directly infiltrated into the right and middle hepatic vein. Right trisegmentectomy was performed, the tumor site was extracorporeally removed and the hepatic posterior segment was autotransplanted. An anastomosis of the right hepatic vein and the inferior vena cava was performed with a vascular prosthesis. The patencies of the anastomosed vessels in the vascular reconstructions were confirmed by Doppler sonography, which was very useful, providing an easy and exact evaluation of hepatic blood flow at the patient's bedside. Throughout the post-operative course before the patient's discharge, no abnormal hepatic function was found. Though cases for which partial hepatic autotransplantation is appropriate may be few, this operation procedure, which applies hepatic transplantation techniques, is significant in that it increases the resectability and achieves curative resection of hepatocellular carcinoma.

Establishment and characterization of human pancreatic carcinoma lines with a high metastatic potential in the liver of nude mice

To investigate of human pancreatic cancer metastasis to the liver, a pancreatic carcinoma line, HPC-3, was injected into the spleens of nude mice. The cells from a few liver metastatic foci of the mice injected with HPC-3 were expanded in vitro and subsequently injected into the spleens of nude mice. By repeating these procedures, we were able to obtain a cell line, designated HPC-3H4. The mice were observed to have liver metastasis in 6 of 6 (100%) cases injected with HPC-3H4, whereas the rate was 0% at 3 weeks after the intrasplenic injection of HPC-3. The tumorigenicity of HPC-3H4 was more rapid than that of HPC-3. The motile activity of HPC-3H4 was also stronger than that of HPC-3, and the adhesion to the extracellular matrix of HPC-3H4 was stronger than that of HPC-3. We also analyzed the cell surface expression of the metastasis-related adhesion molecules. As a result, no substantial changes were observed in the expression level of adhesion molecules. These results suggest that HPC-3H4 is useful for studies aimed at the prevention of liver metastasis.

[Bacteria isolated from surgical infections and their susceptibilities to antimicrobial agents: special references to bacteria isolated between July 1996 and June 1997]

The annual multicenter studies on isolated bacteria from infections in general surgery and their antimicrobial susceptibility have been conducted in 20 facilities in Japan since July 1982. This paper describes the results obtained during period from July 1996 to June 1997. The number of cases investigated as objectives was 217 for one year. A total of 406 strains were isolated from 177 cases (81.6% of total cases). From primary infections 162 strains were isolated, and from postoperative infections 244 strains were isolated, respectively. From primary infections, anaerobic bacteria were predominant, while from postoperative infections, aerobic Gram-positive bacteria were predominant. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus spp. was the highest. In postoperative infections, the majority of them were Enterococcus faecalis, while in primary infections, many of them were Enterococcus avium. The isolation rate of Staphylococcus spp., especially from postoperative infections, followed that of Enterococcus spp. Among anaerobic Gram-positive bacteria, Peptostreptococcus spp. and Streptococcus spp. were commonly isolated from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa in this order, and from postoperative infections, P. aeruginosa was the most predominantly isolated, followed by E. coli and Enterobacter cloacae. Among anaerobic Gram-negative bacteria, Bacteroides fragilis group was the majority of isolates from both types of infections. The isolation rate of aerobic Gram-negative bacillus has decreased with time, while those of anaerobes like B. fragilis group and of aerobic Gram-positive bacteria have gradually increased in both types of infections. We found vancomycin-resistant strains of neither Staphylacoccus aureus nor Enterococcus spp.; however, the MIC of arbekacin for one of strains of S. aureus was 100 micrograms/ml. Both the MIC90's of meropenem and imipenem/cilastatin against P. aeruginosa isolated in this term were 25 micrograms/ml, which were higher than those against the strains isolated in the previous years. Compared with the isolated strains in the year 1995, progress of resistance against carbapenem antibiotics was confirmed.

[Biochemical modulation of 5-FU--effect of low dose CDDP]

A pilot study of continuous or intermittent low dose 5-FU and cisplatin chemotherapy (low-dose FP therapy) was conducted at the Department of Surgery of Sapporo Medical University School of Medicine (Group A) and Sapporo Tsukisamu Hospital, and at the Department of Internal Medicine of the Kochi Prefectural Center Hospital (Group B). The cases with esophageal cancer, stomach cancer, pancreatic cancer, hepatocellular carcinoma or colonic cancer co-existing with their inoperable lesion(s) were considered in this chemotherapy. The rates of complete and partial response and of side effects were studied. Also, the effects of low-dose FP on the prognosis of the patients with pancreatic or colonic cancers were investigated. The procedure consisted of continuous 5-FU 320 mg/m2 i.v. with daily CDDP 2.5 mg/m2 i.v. for five days/week rescue was performed for at least four weeks as a rule. The rates of complete response and partial response were 64% (Group A) and 56% (Group B) in esophageal cancer, 62% (Group A and B) in stomach cancer, 48% (Group A) and 57% (Group B) in colonic cancer, and 8% (Group A) and 21% (Group B). The overall response rate was 57.8%. The frequencies of severe side effect(s) (grades 3 and 4) were within three to eight percent, and no death from side effect(s) was experienced. The effects of low-dose FP therapy on the prognosis of stage IV colonic cancer and stage IV b pancreatic cancer were studied retrospectively. It is suggested that this chemotherapy might contribute to the survival of patients with these two cancers. Otherwise, the chemotherapy of intermittent administration (day by day) of 5-FU 750 mg/m2 i.v. and CDDP 2.5 mg/m2 i.v. was selected in order to decrease the rate of side effects and their severity. The pilot study encountered no severe side effects, no cases with grade 4 side effect were experienced but the remission rates were mostly similar to that of sequential low-dose FP therapy. However, the side effect of low grade ones as symptoms in gastrointestinal tract were observed in more patients. We concluded that sequential or intermittent 5-FU/CDDP therapy might be fairly effective, and since the adjuvant chemotherapy of choice for advanced or recurrent gastrointestinal cancer, their FP therapy might be one of the adjuvant treatments.

Biochemical modulation therapy for pancreatic cancer

It is well known that the clinical course in most patients with advanced pancreatic cancer is not influenced substantially by chemotherapy and/or radiotherapy. However, new chemotherapy, based on the synergistic antitumor activities of 5-fluorouracil (5-FU) and cisplatin (CDDP) producing biochemical modulation in solid cancers diagnosed as adenocarcinoma, has recently been reported to be effective. In gastrointestinal cancers, the optimal concentrations of each drug and the duration of the anticancer effects, as well as adverse effects have been confirmed in pharmacodynamic studies. Our experience of this treatment for advanced pancreatic cancer (stage IV) indicates the usefulness of the antitumor effect in terms of both effect on the tumor size in unresectable patients and prognosis in resectable patients. These results were remarkable in patients diagnosed as stage IV b and/or curability C. Although there were adverse effects, none were severe. However, anything compromising the patient's quality of life must be prevented. Randomized prospective studies of the combination of 5-FU and CDDP are expected in the near future.

Surgical treatment for recurrent tumors of primary malignant melanoma of the esophagus: a case report and review of the literature

The purpose of this communication is to present a case of resection performed for local recurrent tumors of primary malignant melanoma of the esophagus (PMME) and to review the relevant literature. The patient was a 54 year-old man who had received an intraabdominal esophagectomy with a total gastrectomy for primary malignant melanoma of the abdominal esophagus in another hospital, in November 1995. After the initial operation, he was treated as an outpatient. In August 1997, computed tomography and ultrasonography revealed recurrent tumors in the dorsal pancreatic lymph node and in the right adrenal gland. The recurrent tumor of the dorsal pancreas directly invaded the dorsal pancreas parenchyma and occluded the superior mesenteric vein and splenic vein, and the other metastatic tumor in the right adrenal gland existed in the absence of circumference invasion. Metastases of the PMME were confirmed in the dorsal pancreas, the superior mesenteric vein, splenic vein, and right adrenal gland, and were removed by a total pancreatectomy on October 7, 1997. By immunohistochemical staining, we found that the focal areas expressed S-100 protein and HMB-45 antibody. Currently (February 1998), the patient is alive and disease-free. PMME is an extremely rare tumor with a poor prognosis for survival. Only 2 cases of removal of recurrent tumors, including the present case, have been reported. The treatment of choice is surgical resection, even in cases of recurrence, because radiotherapy and/or chemotherapy have not been proven to be beneficial; however, they may play a palliative role if surgery is not possible.

Development of an ulcer in the side-to-side anastomosis of a jejunal pouch after proximal gastrectomy reconstructed by jejunal interposition: report of a case

We present herein the first reported case of a deep ulceration developing in the pouch of a jejunal side-to-side anastomosis following the interposition of a jejunal U-shaped pouch (jejunal pouch), performed as reconstruction. A 47-year-old woman underwent a proximal gastrectomy and interposition of a jejunal pouch for early gastric cancer, 4 months after which she began to develop a fever. Esophagogastroscopy revealed a deep ulceration in the side-to-side anastomosis of the jejunal pouch. Her serum gastrin level was much higher than the normal range, and 24-h monitoring of the intraremnant stomach pH revealed that it was below 7.0 at night. A peptic ulcer was thought to be one of the causes of the pouchitis. Due to the drug-resistant ulceration and fever, a reoperation was performed, in which the jejunal pouch and remnant stomach were removed and Roux-en-Y reconstruction was done. There were no postoperative complications, and the fever resolved after surgery. Reconstruction of the jejunal pouch after proximal gastrectomy is recommended from the standpoint of quality of life (QOL); however, further studies on the size of the remnant stomach and the length of the interposed jejunal pouch are necessary.

Separate functions of alpha2beta1 and alpha3beta1 integrins in the metastatic process of human gastric carcinoma

The expression of alpha2beta1 and alpha3beta1 integrins was studied immunohistochemically in 110 resected human gastric carcinomas. Formalin-fixed and paraffin-embedded samples were serially sectioned and stained with monoclonal antibodies specifically against the alpha2 and alpha3 subunits of beta1 integrins. Approximately 27% of the tumors expressed alpha2beta1 integrin, and 20% expressed alpha3beta1 integrin. The expression of alpha2beta1 integrin was associated with lymph node and liver metastases (P < 0.05 and P < 0.05, respectively), and the expression of alpha3beta1 integrin was associated with liver and peritoneal metastases (P < 0.005 and P < 0.0005, respectively). A multivariate analysis by the logistic regression model revealed that the expression of alpha2beta1 and/or alpha3beta1 integrins was an independent factor related to liver metastasis, and that the expression of alpha3beta1 integrin was as strong an influence on the formation of peritoneal metastases as the depth of invasion. The expression of alpha3beta1 integrin also correlated with increased invasiveness of the tumor; however, there was no correlation between alpha2beta1 integrin expression and the invasiveness. These results suggest that alpha2beta1 and alpha3beta1 integrins have separate influences on the metastatic properties of cancer cells.

[Clinical study of hypopharyngeal carcinoma]

A clinical study was performed of 83 patients with hypopharyngeal cancer treated in the Sapporo Medical University Hospital from 1982 to 1995. Five-year cumulative survival rate was 34.9% in the whole group and 37.2% in the radical surgical and/or radiation treatment group. In the radiation treatment group, the patients with T1, T2, N0 or N1 stage disease, especially those whose original disease responded almost completely to 40Gy irradiation, showed high tumor control rates following full-dose irradiation with or without radical neck dissection. In the radical surgery group, the patients with T4 or N2 stage disease showed better prognosis than those in the radiation group. However, among the patients with N3 lymph node metastases, there were no long-term survivors in either the radiation or the surgery groups.

Inhibition of liver metastasis of human pancreatic carcinoma by angiogenesis inhibitor TNP-470 in combination with cisplatin

The anti-tumor and anti-metastatic effects of O-(chloroacetyl-carbamoyl) fumagillol (TNP-470), an angiogenesis inhibitor, and cisplatin (CDDP), an anti-neoplastic agent, were investigated using our established liver-metastasizing pancreatic carcinoma line, HPC-3H4. HPC-3H4 was injected into the spleens of nude mice. Mice were randomly divided into 5 groups; a control group given saline solution, a group receiving 45 mg/kg TNP-470, a group receiving 90 mg/kg TNP-470, a group receiving 90 mg/kg TNP-470 in combination with 0.25 mg/kg CDDP, and a group receiving 0.25 mg/kg CDDP. In the control group, liver metastasis developed in 14 of 15 mice (93.3%). Liver metastasis developed in 9 of 11 mice (81.8%) receiving 0.25 mg/kg CDDP. It developed in 11 of 15 mice (73.3%) receiving 45 mg/kg TNP-470, in 17 of 18 mice (94.4%) receiving 90 mg/kg TNP-470, and in 4 of 10 mice (40%) receiving 90 mg/kg TNP-470 in combination with 0.25 mg/kg CDDP. TNP-470 in combination with CDDP displayed a significant inhibitory effect on liver metastasis compared to the control. Although TNP-470 alone and CDDP alone had no effect on the tumor growth in vivo, 90 mg/kg TNP-470 in combination with 0.25 mg/kg CDDP had a significant effect. In vitro examinations demonstrated that the growth of HPC-3H4 cells was only mildly inhibited by TNP-470, but the production of vascular endothelial growth factor (VEGF) by HPC-3H4 was clearly inhibited by TNP-470. The inhibitory effect on the production of VEGF was not strong with CDDP treatment. These results indicate that the angiogenesis inhibitor TNP-470 in combination with low-dose CDDP has inhibitory activity against liver metastasis of human pancreatic carcinoma.

[Mechanism of the development of organ failure]

Multiple organ failure (MOF) is a critical condition developing in patients with overwhelming bodily injury resulting from major surgical insult, severe trauma, extensive burns, acute pancreatitis, and sepsis. It has recently become evident that the host response to such injury is the main pathogenetic factor contributing to the development of MOF. The proinflammatory cytokines tumor necrosis factor (TNF) and interleukin (IL)-1 are known to play a pivotal role in the pathogenetic mechanisms of MOF. In response to bodily injury, macrophages produce and release TNF and IL-1, which subsequently induce the production of other cytokines (IL-6, IL-8, etc.) and other endogenous chemical mediators. The resultant systemic inflammation may develop into MOF mainly through neutrophil-endothelial cell interaction when the primary injury is overwhelming or a second inflammatory insult such as sepsis triggers an exacerbated inflammation. It has recently been confirmed that the transcription factor NF-kappaB is involved in the up-regulation of a variety of proinflammatory genes and that cell-mediated immunity is down-regulated in the event of major bodily injury through a shift in the balance between T helper 1 (Th1) and Th2 cytokine response patterns. The molecular immunological mechanisms by which these factors participate in the development of MOF should be characterized.

Carcinoma arising from ectopic pancreas in the stomach: endosonographic detection of malignant change

We present a case of a submucosal tumor in the stomach that was suspicious for malignancy on preoperative endosonography. The resected tumor was histologically diagnosed as a ductal adenocarcinoma that originated in ectopic pancreatic tissue in the gastric wall. Although malignant transformation in ectopic pancreas is extremely rare, it remains an important consideration in the differential diagnosis of gastric submucosal masses.

Lack of survival benefit of extended lymph node dissection for ductal adenocarcinoma of the head of the pancreas: retrospective multi-institutional analysis in Japan

It has not been established that extended lymph node resection is necessary for ductal adenocarcinoma of the head of the pancreas. According to the general rules for the study of pancreatic cancer, a multiinstitutional, retrospective clinical study was undertaken to investigate the efficiency of extended lymph node dissection for this malignancy. Altogether 501 patients underwent resection of the pancreas between 1991 and 1994 at 77 medical facilities; the surgical procedures, staging, lymph node dissection, curability, and survival rate were analyzed retrospectively. Eighteen of the patients died within 30 postoperative days, leaving 483 patients to be studied. The resection was curative microscopically in 94 patients, resulting in a 3-year survival of 29%. Macroscopically curative resection resulted in a 3-year survival of 14%; noncurative resection produced a 3-year survival of 6%. Although extended lymph node dissection was performed on 38 patients in stage I, 42 patients in stage II, 206 patients in stage III, and 1 patient in stage IV, there was no improvement in survival when the results were compared to those seen after standard or palliative lymph node dissection. The extent of lymph node dissection has not affected the prognosis for ductal adenocarcinoma of the head of the pancreas at any stage of the course of the disease. Excessive lymph node dissection in advanced cases does not necessarily lead to a favorable prognosis. The patients who undergo a radical operation with an adequate lymph node dissection have longer survivals.

[The significance of telomerase activity in patients with gastric cancer]

The activation of telomerase is one of step in carcinogenesis. Therefore, it indicates that the detection of telomerase activity in tissues is useful for cancer diagnosis. TRAP assay developed by Kim et al. is sensitive enough to detect telomerase activity from a telomerase expressing cell. Using TRAP assay kit provided by Oncor Inc., we estimated quantitatively the telomerase activity from benign (atrophic gastritis), premalignant (intestinal metaplasia), and malignant tissues in the stomach. Telomerase activity in gastric cancer tissues was significantly higher than that in tissues which are characterized histologically as intestinal metaplasia or atrophic gastritis. In addition, to exclude interference with TRAP assay by telomerase or PCR inhibitor when telomerase activity was not observed in cancer tissues, the use of internal control (ITAS or TSNT) and dilution of samples should be performed.

Close correlation between increased sialyl-Lewisx expression and metastasis in human gastric carcinoma

Expression of sialyl-Lewisx (sLex) antigen was studied immunohistochemically in 110 resected human gastric carcinomas using an anti-sLex monoclonal antibody. Lymph node, liver, and peritoneal metastases were clearly more prevalent in tumors expressing high levels of sLex than in those with no or low-level sLex expression. No correlation was found between sLex expression and histologic grade or histologic type of the Lauren classification. Among the tumors with lymph node metastasis, 44% expressed high levels of sLex in both the primary tumor and involved lymph nodes, and 14% of the metastatic lesions demonstrated increased sLex expression. The 5-year survival rate of the patients undergoing complete (R0) gastric resections was 60% in the sLex high-expression group, which was significantly lower than that of the sLex low-expression group (81%) and of the no-expression group (87%) (p < 0.05). These results suggest that high-level sLex expression is related to both an increased risk of metastasis and poor prognosis in gastric cancer patients.

Results of 1001 pancreatic resections for invasive ductal adenocarcinoma of the pancreas

OBJECTIVE

To evaluate the recent results of pancreatic resection in patients with invasive ductal adenocarcinoma of the pancreas.

DESIGN

Retrospective study.

SETTING

Seventy-seven medical facilities belonging to the Japan Society of Pancreatic Surgery.

PATIENTS

One thousand one patients who underwent a resection of the pancreas between January, 1, 1991, and December 31, 1994.

MAIN OUTCOME MEASURES

Morbidity and survival after surgery for pancreatic cancer according to the modified TNM classification of the International Union Against Cancer.

RESULTS

After pancreatic resection, the cumulative postoperative survival rates at 1 and 3 years were 44.5% and 10.3%, respectively. Patients with early-stage cancers had a more prolonged survival time, ie, the cumulative 3-year survival rates for patients with stage I or stage II cancers were 50.4% and 45.5%, respectively; the survival rates for patients with stage III and stage IVa and IVb cancers were 17.6%, 5.7%, and 0%, respectively. The survival rate for patients with N1 or N2 metastasis did not differ appreciably, and both groups had significantly better survival rates than patients with N3 metastasis (P < .001). A significant difference in the postoperative survival time of N1 metastasis was observed between patients with no lymph node dissection (mean survival, 326.4 days) and patients who received a lymph node dissection (D1) (mean survival, 478.2 days) (P < or = .01).

CONCLUSIONS

The recent results of pancreatic resection for invasive ductal adenocarcinoma of the pancreas are generally unsatisfactory. Although the outcome of the patients with an N1 metastasis can be improved if they receive N1 lymph node dissection (D1), an extensive lymph node dissection in advanced cancers does not necessarily produce a favorable prognosis.

[Combination chemotherapy of continuous infusion 5-fluorouracil and daily low-dose cisplatin in advanced gastrointestinal and lung adenocarcinoma]

Continuous intravenous infusion (c.v.i.) of 5-fluorouracil (5-FU) plus daily low-dose cisplatin (CDDP) was evaluated in 45 patients with advanced and recurrent unresected colorectal, lung, gastric and pancreatic adenocarcinoma. 5-FU was given at a dose of 320 mg/m2/day, c.v.i. for 4 weeks, and CDDP between 3.5 to 7 mg/m2/day, infused for one hour five times a week for 4 weeks. Patients received 1 to 3 cycles of treatment (average 1.5 cycle). Pancreatic cancer cases needed longer treatment periods (2.25 cycles). The response rate of colorectal cancer cases was 57.7% (15/26), pancreas cancer 40%, gastric cancer 62.5%, and lung cancer 66.7%. The overall response rate was 57.8%. No severe side effects occurred in any of these cases. These data indicate that this combination 5-FU + daily low-dose CDDP chemotherapy is effective in the treatment of advanced gastrointestinal and lung adenocarcinoma.

[Isolation rate of Enterococcus spp. from surgical infections and their susceptibilities]

Enterococcus spp. isolated from surgical infections during the period from July 1982 to June 1995 were investigated in a multicenter study involving 19 hospitals in Japan, and the following results were obtained. 1. Though the isolation rate of Enterococcus faecalis and other Enterococcus spp. were not high from primary infections, and from postoperative infections the isolation rate of other Enterococcus spp. was also low, the isolation rate of E. faecalis was highest from postoperative infections after 1993. 2. Vancomycin (VCM) showed strongest activity against E. faecalis, and followed by those of ampicillin (ABPC), imipenem. levofloxacin (LVFX) and meropenem in this order. Against other Enterococcus spp., VCM showed strongest activity, and followed by those of ABPC and LVFX. There were no resistant strains against VCM.

[Bacteria isolated from surgical infections and their susceptibilities to antimicrobial agents. Special references to bacteria isolated between July 1995 and June 1996]

Isolated bacteria from infections in general surgery during the period from July 1994 to June 1995 were investigated in a multicenter study in Japan, and the following results were obtained. One hundred and sixty-four strains were isolated from primary infections, and 202 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-positive bacteria were predominant, while from post operative infections, aerobic Gram-positive bacteria were predominant. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus faecalis was the highest, followed by that of Staphylococcus aureus from postoperative infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among anaerobic Gram-negative, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa in this order, and from postoperative infections, P. aeruginosa was the most predominantly isolated, followed by Enterobacter spp. and Klebsiella spp. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. We noticed that MICs of cefazolin against three out of 23 strains of E. coli were higher than 100 micrograms/ml. Among anaerobic bacteria, there were many resistant strains against penicillins and cephems with MICs higher than 100 micrograms/ml, and the same trend was observed among other Bacteroides spp. and Prevotella spp.

Beneficial effects of administering intraportal prostaglandin E1 postoperatively to hepatectomy patients with massive intraoperative blood loss

Massive intraoperative blood loss is a major cause of complications following hepatectomy. To evaluate the efficacy of intraportal prostaglandin E1 (PGE1) for preventing liver deterioration in hepatectomy patients with an intraoperative blood loss of over 2000 ml, a retrospective analysis was conducted on 10 patients given intraportal PGE1 (portal group), 6 given intravenous PGE1 (venous group), and 10 given no treatment (control group). PGE1 was infused at 250 or 500 micrograms/day in the portal group and at 720 micrograms/day in the venous group, and continued for 3 days postoperatively. Alanine aminotransferase (ALT) and total bilirubin (T.Bil) were measured on postoperative days (PODs) 1, 3, 5, and 7. ALT was lower in the portal group than in the other two groups on each POD, and significantly lower than in the control group on POD3 (P < 0.05). T.Bil was significantly lower in the portal group than in the control group on PODs 5 and 7 (P < 0.05). T.Bil on POD 7 was under 1.5 mg/dl in 1 (10.0%), 6 (60.0%), and 2 (33.3%) of the control, portal, and venous group patients, respectively, with a significant difference between the control and portal groups (P < 0.05). These results confirmed that intraportal PGE1 was beneficial for improving hepatic function and preventing cholestasis in patients with a blood loss of over 2000 ml at risk of developing postoperative liver deterioration.

[Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents. Special references to bacteria isolated between July 1994 and June 1995]

Isolated bacteria from infections in general surgery during the period from July 1994 to June 1995 were investigated by a multicenter study in Japan, and the following results were obtained. One hundred and fifty-three strains were isolated from primary infections, and 143 strains were isolated from postoperative infections. From primary infections, both anaerobic Gram-positive and-negative bacteria were predominant, and from postoperative infections, aerobic Gram-positive bacteria were predominant. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus faecalis was highest, followed by that of Staphylococcus aureus from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Streptococcus intermedius was highest from primary infections, but from postoperative infections anaerobic Gram-positive bacteria was uncommon. Among aerobic Gram-negative bacteria, Escherichia coli was most predominantly isolated from primary infections, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa in this order. From postoperative infections, P. aeruginosa was most predominantly isolated, followed by Serratia marcescens and E. coli. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. We have noticed that resistant strains against imipenem and ofloxacin were increasing among P. aeruginosa and resistant strains against cefazolin were increasing among E. coli. MICs of cefazolin against four out of 30 strains of E. coli were higher than 100 micrograms/ml, and MICs of imipenem was higher than 50 micrograms/ml against 5 out of 22 strains of P. aeruginosa.

Inhibition of liver metastasis of human gastric carcinoma by angiogenesis inhibitor TNP-470

The anti-tumor and anti-metastatic effects of TNP-470, an angiogenesis inhibitor, and mitomycin C (MMC), a representative anti-neoplastic agent, were investigated using our established liver-metastasizing gastric carcinoma line, AZ-H5c. AZ-H5c was injected into the spleen of nude mice which had been randomly divided into 4 groups; a control group given saline solution, a group receiving 15 mg/kg TNP-470, a group receiving 30 mg/kg TNP-470 and a group receiving 2 mg/kg MMC. TNP-470 was given s.c. on alternate days for 5 weeks from day 10 after intrasplenic injection, and MMC was administered intraperitoneally (i.p.) once a week from day 10 after intrasplenic injection. In the control group, liver metastasis developed in 13 of 16 mice (81%). Liver metastasis developed in 6 of 11 mice (55%) receiving MMC. In contrast, liver metastasis developed in 4 of 8 mice (50%) receiving 15 mg/kg TNP-470, and in 0 of 14 mice (0%) receiving 30 mg/kg TNP-470. However, TNP-470 had no effect on the tumor growth. These results indicate that the angiogenesis inhibitor TNP-470 has a strong inhibitory activity against in vivo liver metastasis of human gastric carcinoma.

[Isolation rate of Pseudomonas aeruginosa from surgical infections and their susceptibilities]

Pseudomonas aeruginosa isolated from surgical infections during the period from July 1982 to June 1995 were investigated in a multicenter study involving 19 hospitals in Japan, and the following results were obtained. 1. Though the isolation rate of P. aeruginosa was not high from primary infections, it was more frequently isolated from postoperative infections throughout the study period. Enterococcus spp., P. aeruginosa and Staphylococcus aureus including MRSA were predominant among postoperative infections. From the postoperative cases that had previous antibiotic treatment, Enterococcus spp., MRSA and P. aeruginosa were more predominantly isolated than from those without previous treatments with antibiotics. 2. Cefozopran, ceftazidime, cefsulodin, aztreonam, carumonam, gentamicin, amikacin and ofloxacin had strong activities against P. aeruginosa. We recognize recently that antibiotic-resistant strains of P. aeruginosa against imipenem and ofloxacin have been increasing year by year.

[Isolation rate of E. coli from surgical infections and their susceptibilities]

Escherichia coli isolated from surgical infections during the period from July 1983 to June 1995 were investigated in a multicenter study involving 19 hospitals in Japan, and the following results were obtained. 1. Although the isolation rate of E. coli was not high from postoperative infections, it was most frequently isolated from primary infections throughout the study period. E. coli, Klebsiella spp. and anaerobic bacteria were predominant from fresh infections. From the cases that had previous antibiotics treatment, Enterococcus spp. were the most predominant isolates followed by MRSA and Pseudomonas spp. in this order. 2. Against E. coli, cefozopran, carumonam and aztreonam had the strongest activity, followed by cefmenoxime, imipenem, latamoxef, gentamicin and ofloxacin. Recently, we have noticed that antibiotic resistant E. coli strains particularly against cefazolin are increasing year by year.

Correlation between nm23 protein and several cell adhesion molecules in human gastric carcinoma

The correlation between nm23 protein (nm23) expression and the expression of several cell adhesion molecules was studied immunohistochemically in 110 resected gastric carcinomas. Formalin-fixed and paraffin-embedded samples were serially sectioned and stained with antibodies against nm23, integrin beta1 subfamily members (alpha2beta1, alpha3beta1 and alpha4beta1), LFA-1, ICAM-1, sialyl Lewis(x) (sLex) and CD44H, -V3, and -V6. Primary carcinomas presenting with either lymph node involvement or liver metastasis expressed significantly reduced levels of nm23 compared to tumors without metastasis. The percent of tumors expressing each adhesion molecule was as follows: alpha2beta1, 27.3%; alpha3beta1, 20.0%; alpha4beta1, 14.5%; LFA-1, 14.5%; ICAM-1, 12.7%; sLex, 67.3%; CD44H, 55.5%; CD44V3, 20.0%; and CD44V6, 4.5%. Expression of alpha2beta1 integrin and high levels of sLex were significantly correlated with lymph node metastasis, and expression of alpha3beta1 integrin and high levels of sLex were correlated with liver metastasis. Expression of ICAM-1 was inversely correlated with liver metastasis. Comparing the expression of each cell adhesion molecule with nm23 immunoreactivity, expression of sLex was significantly associated with nm23 expression. Of tumors expressing high levels of sLex, 75% showed reduced nm23 expression, compared to 52% of tumors with weak or no sLex expression (P < 0.05). A similar tendency was also observed in the metastasized secondary tumors. These results suggest that reduced nm23 expression may promote the metastatic properties of cancer cells in concert with increased sLex expression.

Glutamine-enriched total parenteral nutrition enhances plasma glutathione in the resting state

Glutathione (GSH) is the major intracellular antioxidant and is essential to normal cell function and replication. Cysteine and other thiol compounds have been considered rate-limiting for GSH biosynthesis, but recent studies have demonstrated that glutamine (GLN) becomes essential during metabolic stress to replete tissue GSH levels which have become depleted. To determine the role of GLN supplementation in the resting, nonstressed state, we studied three groups of Wistar rats. The animals were catheterized and randomly assigned to one of three groups; (1) chow ad libitum group receiving iv saline (control), (2) standard total parenteral nutrition (STA-TPN) group, and (3) glutamine-enriched TPN (GLN-TPN) group. The intravenously fed animals received no rat chow. The infusions were administered at a rate of 2.2 ml/hr for 4 days and all animals were harvested on the fifth day of study. The GLN-TPN group had a significantly higher plasma GSH level than STA-TPN or control animals (P < 0.01). The hepatic concentration of GSH and the oxidized GSH/reduced GSH were similar in all groups. GLN-TPN had a significantly lower plasma ALT level than the control group (P < 0.05). The control group had a significantly higher ALP level than STA-TPN and GLN-TPN animals (P < 0.01). There were no significant differences in other measures of hepatic functions among the three groups. Our data demonstrate that in this model GLN-enriched TPN enhances plasma GSH concentrations, while maintaining hepatic GSH stores. This suggests that GSH turnover is altered during glutamine-enriched TPN, which may explain how dietary GLN supplementation enhances tissue antioxidant capacity.

Establishment and characterization of human gastric carcinoma lines with high metastatic potential in the liver: changes in integrin expression associated with the ability to metastasize in the liver of nude mice

There is a need to establish animal models which are suitable for investigation of human gastric cancer metastasis to the liver. To this end, a human gastric carcinoma line, AZ521 was injected into the spleens of nude mice. Cells from the few liver metastatic foci of injected AZ521 were expanded "in vitro" and subsequently injected into the spleens of nude mice. By repeating these procedures three times, we were able to obtain a cell line, designated as AZ-H3c, with high metastatic potential in nude mice. Liver metastasis developed in 15 of 21 (71%) animals injected with AZ-H3c, but only in 14% of those injected with parental AZ521. Further, AZ-H3c caused faster tumor development than did AZ521. However, the primary AZ-H3c tumors and liver metastatic AZ-H3c tumors showed essentially the same histological appearance. We also analyzed the cell surface expression of adhesion molecules. The data showed that the expression of VLA-1, VLA-2, VLA-3, VLA-4, VLA-5 was enhanced in AZ-H3c. In contrast, the expression of VLA-6, (alpha(v)beta3), E-cadherin, ICAM-1 and LFA-1 was reduced in this high-metastatic line. These results suggest that (beta1) integrins play an important role in the liver metastasis of human gastric carcinoma cells. Our high-metastatic line should be useful for studies aimed at the prevention of liver metastasis.

The enhanced effect of parenteral nutrition on hepatotoxicity

Recent studies have demonstrated that enteral feedings are associated with decreased morbidity and mortality when compared with parenteral feedings. In this study, we hypothesized that (1) route of feeding affects morbidity and mortality in a model of drug-induced hepatotoxicity and (2) glutamine and polymyxin B, which have been reported to reduce bacterial translocation, attenuate this effect when TPN is used. Male virus-free Wistar rats were divided into six groups receiving: (1) ad libitum chow infused with intravenous (IV) saline (Chow), (2) standard total parenteral nutrition solution administered via gastrostomy (Enteral), (3) standard total parenteral nutrition infused via a central catheter (TPN), (4) standard TPN containing polymyxin B (TPN-PolyB), and (5) glutamine-enriched TPN (TPN-GLN). A final group of animals was not manipulated but harvested at time 0 to serve as controls. The dose of polymyxin B used in this study has previously been shown to significantly reduce bacterial translocation. After 4 d of feeding, all rats received 5% dextrose infusion after an intraperitoneal (IP) injection of acetaminophen (ACM). Rats were sacrificed 0, 6, and 24 h after ACM administration. The TPN group had a lower liver glutathione level after 6 and 24 h, greater levels of liver enzymes after 24 h, and a lower survival rate after 24 h compared with Chow. The Enteral group had less morbidity than TPN but greater morbidity than Chow. Addition of polymyxin B or glutamine had a minimal effect on morbidity or mortality when compared to the TPN group. We conclude that rats receiving IV nutrition have greater morbidity and mortality following a standard hepatic insult than chow-fed rats. We speculate that alteration of microsomal cytochrome P-450 or drug clearance may be related to the benefits of providing nutrients by the gastrointestinal route.

The significance of nm23 protein expression in human gastric carcinomas

The clinical significance of nm23 protein (nm23) expression was studied in tissue samples from 110 patients with primary gastric cancer by immunohistochemical staining with the anti-nm23 antibody. Primary carcinomas with either lymph node involvement or liver metastasis expressed significantly reduced levels of nm23 compared to those without metastasis. This relationship was clearer in the more differentiated adenocarcinomas than in the poorly differentiated adenocarcinomas. However, there was no correlation between nm23 expression and depth of invasion, quantity of stroma, infiltrating growth pattern, or macroscopic type. The cumulative 5-year survival rates based on nm23 immunoreactivity within the primary tumor were significantly higher in the nonreduced expression group (72%) than in the reduced expression group (45%). A multivariate analysis revealed that nm23 expression levels influence the outcome of patients as strongly as depth of invasion and more strongly than the other clinicopathological factors. These results suggest that the degree of nm23 expression is closely related to the metastatic potential of gastric carcinoma cells and can be used as a prognostic indicator independent of the clinicopathological features.

The ratio of reduced glutathione/oxidized glutathione is maintained in the liver during short-term hepatic hypoxia

Controversy persists as to whether reperfusion-induced injuries actually occur in the hepatocyte. The liver is the major source of glutathione, a scavenger of hydrogen peroxide. The aim of this study was to evaluate the sensitivity of the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) [GSH:GSSG] as an index of hepatic metabolic stress. A total of 121 rats were studied. The superior mesenteric vein (SMV) was occluded for 30 min, and this was followed by 0, 10, or 120 min of reperfusion. Total glutathione and GSSG levels in the liver, bile, and plasma were quantified, using glutathione reductase-coupled enzymatic assays. Results indicated that the hepatic GSH/GSSG ratio was maintained after an occlusion of the SMV, despite a decrease in adenosine triphosphate (ATP) level and energy charge potential. However, plasma levels of total glutathione and GSSG in the inferior vena cava increased after SMV occlusion and continued to increase after reperfusion. Biliary GSSG efflux decreased during 30-min occlusion of the SMV, and remained low even after reperfusion. The liver maintains homeostasis despite a decrease in biliary GSSG efflux, probably by secreting excess GSSG into the hepatic vein when the SMV is occluded. We conclude that the total amount of glutathione and GSSG in the plasma is directly correlated with oxidative stress in the liver.

[Bacteria isolated from intraabdominal infection and their susceptibilities to antimicrobial agents]

Bacteria isolated from intraabdominal infections during the period from July 1982 to June 1993 were investigated with regard to their classifications according to a joint research by 9 university hospitals in Japan. The following results were obtained. 1. A total of 971 strains were isolated from 684 out of 597 patients with peritonitis, and 287 strains out of 971 were isolated from postoperative peritonitis. 2. The most predominant organism isolated from patients with acute peritonitis was Escherichia coli (28%), followed by Bacteroides fragilis group (17%), Gram-positive anaerobic cocci (16%), Enterococcus spp. (9%) and Klebsiella spp. (8%). 3. Against E. coli, cefmenoxime, cefuzonam, cefozopran, aztreonam and carumonam showed MIC50 less than 0.05 micrograms/ml. Against B. fragilis group, erthromycin, clindamycin, imipenem, lincomycin and latamoxef showed MIC50 less than 0.78 micrograms/ml. 4. The most predominant organism isolated from patients with postoperative peritonitis was Enterococcus spp. (20%) and followed by Pseudomonas spp. (14%), and Staphylococcus spp. (13%), E. coli (9%), Enterobacter spp. (8%) and Klebsiella spp. (8%). We suggest that cefazolin, cefmetazole, flomoxef, cefmenoxime, cefuzonam, and latamoxef are the first choice agents in empiric therapy for the treatment of acute peritonitis.

[Year to year changes in isolation frequencies of different bacteria from postoperative infections]

Bacterial species isolated from postoperative infections during the period from July 1982 to June 1993 were studied regarding isolation frequencies of different species in different years in a joint research project involving nine (9) university hospitals in Japan. The obtained results are summarized as follows. (1) Altogether, 1,453 strains were isolated with 153 strains obtained during the most recent one year from July of 1992 through June of 1993. The most numerous source of isolation was postoperative intra-abdominal sepsis. (2) Gram-positive cocci were the most often isolated, among them methicillin-resistant Staphylococcus aureus was isolated in increasing frequencies until June, 1992. (3) In the last one year, Enterococcus spp. was isolated the most from postoperative infections followed by Staphylococcus spp. and Pseudomonas spp. Rates of isolation of anaerobic bacteria were relatively low with annual isolation frequencies ranging 8 to 15 per cent.

Unusual complications caused by endo-clip migration following a laparoscopic cholecystectomy: report of a case

We present herein the case of a woman who developed unexpected complications following a laparoscopic cholecystectomy. The clinical manifestations were unique in that symptoms of obstructive jaundice were in fact caused by endo-clips which had migrated into the common bile duct, and the resulting choledochoduodenal fistula presented as persistent cholangitis. While the overall safety of this new procedure appears to be superior to that of open cholecystectomy, the risk of bile duct injury seems more likely. This case stresses the need for caution by surgeons, and emphasizes the necessity for careful surveillance and strict follow-up to ensure the safety of this procedure.