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Biomedical subjects

R Denno

Publications and source records attributed to R Denno.

At least 19 recordsLinked to original sources

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.

Cell Line, Tumor↗

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.

Adenocarcinoma↗

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.

Adenocarcinoma↗

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.

Animals↗

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.

Adenocarcinoma↗

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.

Aged↗

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.

Antioxidants↗

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.

Adenocarcinoma↗

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.

Animals↗

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.

Animals↗

[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.

Adenocarcinoma↗

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.

Adult↗

[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.

Anti-Bacterial Agents↗

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.

Adenocarcinoma↗

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.

Duodenal Ulcer↗

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.

Extracellular Matrix Proteins↗

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.

Adult↗