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Yoshihide Otani

Publications and source records attributed to Yoshihide Otani.

At least 55 records · Page 3Linked to original sources

Matrix metalloproteinase inhibitor, marimastat, decreases peritoneal spread of gastric carcinoma in nude mice.

Marimastat, a matrix metalloproteinese inhibitor, was examined for the ability to prevent peritoneal dissemination of a human gastric cancer xenograft, TMK-1. Even with novel approaches such as molecular targeting of cancer chemotherapy, peritoneal dissemination of gastric cancer has little sensitivity to anticancer drugs, and it is impossible to inhibit its growth completely. Intraperitoneal injection of TMK-1 into nude mice at 5 x 10( 5) cells / body resulted in carcinomatous peritonitis that mimicked clinical cases. Continuous administration of marimastat (18 mg / kg / day) from 24 h after the tumor inoculation successfully inhibited the growth of peritoneal dissemination nodules. Combined administration of marimastat (18 mg / kg / day) and mitomycin C (MMC, 2 mg / kg) showed synergistic inhibition of growth of peritoneal dissemination, being superior to MMC alone (2 mg / kg). Although marimastat alone could not increase survival time with statistical significance, combined administration of marimastat and MMC had a survival benefit with statistical significance. The combination of marimastat and MMC increased the preventive effect on peritoneal dissemination. Marimastat seems to be a candidate for the prevention of peritoneal spread of gastric carcinoma.

Animals↗

Arteriovenous shunting blood flow is intravitally observed in the stomach after thermal injury in rats.

Microcirculatory disturbance of the gastric wall is a crucial factor in the development of gastric mucosal lesions induced by Helicobacter pylori, anti-inflammatory drugs and stress. Opening of the arteriovenous shunting channel after thermal injury is one of the possible mechanisms to reduce mucosal blood flow. However, no in vivo observation of arteriovenous shunting blood flow in the stomach has been reported. To assess gastric microcirculatory disturbance, especially arteriovenous shunting blood flow after thermal injury by in vivo microsciopy, male Wistar rats were anesthetized and thermal injury was inflicted on the back skin. Gastric microvascular images were observed by in vivo microscopy. Rolling of leukocytes labelled with carboxyfluorescein diacetate, succinimidyl ester were counted and blood flow dynamics were observed by flow of a micro dye, monastral blue B (MBB). The endothelial damage was assessed by deposits of MBB 5 min after the administration. Arteriovenous shunting blood flow is difficult to detect by normal methods, but it could be observed by How of MBB after thermal injury. Statistical analysis showed a significant difference in the ratio of arteriovenous shunting blood flow detection between the control (no injury) (0%; n = 15) and thermal injury (5 hrs after thermal injury) (28.6%; n = 14) groups. In the thermal injury group, the percentage of rolling leukocytes and the area of monastral blue B deposits increased, and the venular walls tended to be irregular. The total length of erosion increased time-dependently after thermal injury, and the length at 5 hrs was approximately 2 times larger than that at 2 hrs. Arteriovenous shunting blood flow is intravitally observed after thermal injury. A-V shunting blood flow can be a cause of mucosal hypoperfusion. It is suggested that the microcirculatory disturbance seen 5 hrs after thermal injury is contributed to the final step of erosion formation.

Animals↗

[A novel combined chemotherapy using TS-1 and low-dose cisplatin against liver metastasis of gastric cancer].

We used a novel combination chemotherapy of TS-1 and low-dose cisplatin (CDDP) with 4 gastric cancer patients with liver metastases (one far advanced and 3 recurrent patients). TS-1 was administered at 80 mg-120 mg/body/day, twice daily for 3 weeks followed by a 2-week interval as one cycle, and CDDP was administered at 6 mg/m2/day div, for 5 days followed by a 2-day interval (1 cycle for an inpatient) or at 6 mg/m2/day div, at 5 times for 2-3 weeks (1 cycle for an outpatient). Efficacy and toxicity were evaluated after 3-6 cycles of the regimen, as long as the patients tolerated the regimen without severe side effects. This regimen resulted in 1 complete response, 2 partial responses and 1 progressive disease, showing a 75% efficacy rate. One patient experienced grade 2 nausea from this regimen, which was ameliorated by means of prolonging the interval of CDDP-administration. Thus, the regimen is useful to maintain patients' quality of life without severe adverse effects, and has a high efficacy in gastric cancer patients with liver metastases.

Administration, Oral↗

Surgically treated Cronkhite-Canada syndrome associated with gastric cancer.

Cronkhite-Canada syndrome is generally accepted to be a benign disorder, with 374 reported cases to the present. Worldwide, there have been 18 previously reported cases of Cronkhite-Canada syndrome associated with gastric cancer. In this report we describe a case of a 52-year-old man with the clinical features of Cronkhite-Canada syndrome combined with gastric cancer. Although the gastric tumor was located at the antrum of the stomach, we performed a total gastrectomy because of the edematous swelling and high risk of malignancy in the remnant stomach. As Cronkhite-Canada syndrome may be a premalignant condition for gastric cancer, as well as for colorectal cancer, we suggest periodic examination of the stomach, colon, and rectum for patients with Cronkhite-Canada syndrome.

Journal Article↗

Pyrimidine nucleoside phosphorylase and dihydropyrimidine dehydrogenase indicate chemosensitivity of human colon cancer specimens to doxifluridine and 5-fluorouracil, respectively.

We have assessed pyrimidine nucleoside phosphorylase (PyNPase) and dihydropyrimidine dehydrogenase (DPD) activity to compare the chemosensitivity of 5-fluorouracil (5-FU) and doxifluridine (5'-DFUR). Tumor samples were prepared from fresh surgical specimens of 28 patients with advanced colon carcinoma. The activity levels of the two enzymes were assessed as indicators of chemosensitivity to 5'-DFUR and 5-FU. PyNPase activity was analyzed using the HPLC method, and DPD activity was assessed according to the methods of Naguib et al. (1985). A histoculture drug response assay (HDRA) was conducted according to the methods described by Furukawa et al. (1992). The mean and standard deviation of PyNPase activity in the tumor tissue was 110 +/- 48.6 &mgr;g 5-FU/mg protein/h, which was statistically higher than the corresponding value obtained in normal tissue (60 +/- 43.1 &mgr;g 5-FU/mg protein/h) (P < 0.005). When chemosensitivity to the two drug forms was compared in 16 samples obtained from 16 cases with colon cancer, 1 specimen was sensitive to both drug forms, 3 specimens were exclusively sensitive to 5'-DFUR, 5 specimens were exclusively sensitive to 5-FU, and the other 7 specimens were insensitive to both drugs, without significance. High PyNPase activity was associated with a high chemosensitivity to 5'-DFUR, and high DPD activity correlated with a low chemosensitivity to 5-FU. However, the converse relationship was not found. We suggest that the activity of PyNPase and DPD represents a reliable indicator for the chemosensitivity of colon cancer to 5'-DFUR and 5-FU, respectively.

Journal Article↗

Docetaxel enhances the cytotoxicity of anthracyclines by increasing intracellular drug accumulation.

We assessed the combined antitumor activity of docetaxel and doxorubicin (DXR) and tetrahydropyranyl-adriamycin (THP) using the human breast carcinoma cell lines R-27 and MDA-MB-231. Synergistic antitumor activity was observed for both combined docetaxel and DXR, and docetaxel and THP against R-27 cells when contacted simultaneously. However, only additive effects were observed against MDA-MB-231 cells. Intracellular concentrations of DXR and THP in R-27 cells were significantly increased by docetaxel pretreatment, however, this increase was not observed in MDA-MB-231 cells, which exhibited only additive sensitivity to the treatment. Thus, docetaxel increased the antitumor activity of anthracyclines by increasing their intracellular concentrations.

Antineoplastic Combined Chemotherapy Protocols↗

Different pathways of 5-fluorouracil metabolism after continuous venous or bolus injection in patients with colon carcinoma: possible predictive value of thymidylate synthetase mRNA and ribonucleotide reductase for 5-fluorouracil sensitivity.

BACKGROUND: The mode of action of 5-fluorouracil (5-FU) was evaluated in patients with advanced colon cancer treated preoperatively with 5-FU. PATIENTS AND METHODS: After obtaining informed consent, 30 patients were randomized into three groups: untreated controls (n = 16), continuous intravenous infusion of 5-FU for 5 days at a dose of 320 mg/m2 (CIV group, n = 6), or bolus intravenous injection of 5-FU for 5 days at the same dose (bolus group, n = 8). Surgically-resected samples were analyzed by 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay to detect sensitivity to 5-FU. Samples were also assayed for thymidylate synthetase (TS) activity, levels of 5-FU RNA (F-RNA), ribonucleotide reductase (RNR) activity, and TS mRNA levels expressed as the ratio of TS mRNA to beta-actin mRNA. RESULTS: While similar levels of TS inhibition were observed in the civ and bolus groups, F-RNA levels were significantly increased in the bolus group. The TS mRNA ratio was significantly higher in the 5-FU-resistant group than 5-FU-sensitive group. In the control group, the 5-FU-sensitive group showed higher RNR enzymatic activity compared to the 5-FU-resistant group. CONCLUSION: Our results suggested that the method of administration resulted in the induction of different 5-FU metabolic pathways. High TS mRNA and low RNR activity may be concerned with 5-FU-resistance in patients with advanced colon carcinoma.

Colonic Neoplasms↗

Independent antitumor spectrum of UCN-01 (7-hydroxystaurosporine) against gastric and colorectal cancers as detected by MTT assay.

To evaluate the clinical usefulness of 7-hydroxystaurosporine (UCN-01), we compared the antitumor spectrum of UCN-01 with those of conventional antitumor agents against 40 fresh gastric and 40 fresh colorectal cancer specimens using the MTT assay. At a cut-off concentration of 30 micrograms/ml, UCN-01 showed a higher efficacy rate than mitomycin C (MMC), cisplatin, and 5-fluorouracil (5-FU) against both gastric and colorectal cancers. With respect to the gastric cancer specimens, the antitumor spectrum of UCN-01 was independent from those of the other agents, while the patterns of antitumor effects of the conventional agents all correlated significantly with each other. For the colorectal cancer specimens, the pattern of UCN-01-sensitivity did not correlate with the patterns for 5-FU or MMC. In conclusion, UCN-01 may be useful for clinical application against gastric and colorectal cancer due to its different antitumor spectrum from conventionally available agents.

Aged↗

Preoperative combination chemotherapy with S-1 and low dose cisplatin against highly advanced gastric carcinoma.

We performed preoperative chemotherapy with S-1 and low-dose CDDP (TSLD) to treat 9 patients of highly advanced gastric cancer. Five cases showed significant effect with severe fibrosis diagnosed as grade 1b-2 effect in histology, and all 9 cases showed at least grade 1a effect in either primary lesion or lymph node. While toxicity of less than grade 3 (gastrointestinal disorder and/or bone marrow suppression) were observed in 5 out of 9 cases (55.6%), no symptom was observed in 3 out of the 5 patients. We conclude that the TSLD is useful to control highly advanced gastric cancer.

Adenocarcinoma↗

Antitumor activity of doxorubicin in combination with docetaxel against human breast cancer xenografts.

In this study we assessed the in vivo antitumor activity of combined docetaxel (DOCE) and doxorubicin (DXR) treatment using 2 human breast carcinoma cell xenografts (R-27 and MX-1) in the nude mouse model. The transplanted tumors were allowed to reach exponential growth, whereupon 10 or 40 mg DOCE per kg alone (i.p.), 8 mg DXR per kg alone (i.v.), or 10 mg/kg DOCE (i.p.) and 8 mg/kg of DXR (i.v.), in the sequence of DOCE followed by DXR, were administered. The in vivo antitumor activity of combined DOCE and DXR was synergistic against R-27 and additive against MX-1. P-glycoprotein (P-gp) was detected immunohistochemically, and was highly expressed in R-27, but not in MX-1. In conclusion, DOCE may increase the antitumor activity of DXR against P-gp-positive breast cancer xenografts, such that the DOCE and DXR combination may be a useful treatment in clinical breast cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Cancer chemotherapy chemosensitivity testing is useful in evaluating the appropriate adjuvant cancer chemotherapy for stages III/IV gastric cancers without peritoneal dissemination.

BACKGROUND: Because of the low chemosensitivity of gastric cancer to conventional antitumor agents, the role of adjuvant chemotherapy for patients with advanced gastric cancer is controversial. We have previously proposed the necessity to evaluate the appropriateness of particular adjuvant cancer chemotherapies in individual advanced gastric cancer patients using chemosensitivity testing. In the present study, we compared the chemosensitivity and clinical outcomes of patients with Stages III and IV gastric cancer. PATIENTS AND METHODS: A total of 282 patients with advanced gastric cancer were analyzed retrospectively in terms of chemosensitivity as detected by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and survival outcome after surgery. Patients were split into groups according to Stage III or IV gastric cancer, then categorized into those that received surgery without chemotherapy (surgery-alone), and those that received adjuvant chemotherapy, for which all the evaluable cases were further divided into sensitive and resistant cases as determined by MTT assay. RESULTS: For Stage III gastric cancer patients, the sensitive group had a more favorable survival outcome than the other two groups. For Stage IV gastric cancer patients, the sensitive groups, had a more favorable survival outcome than the other two groups, but only in the absence of peritoneal dissemination. CONCLUSION: Chemosensitivity testing, based on the MTT assay, was useful in evaluating the appropriate cancer chemotherapy for patients with Stages III/IV gastric cancer without peritoneal dissemination.

Aged↗

Alteration of DNA methylation status induced by epidermal growth factor in gastric cancer cell line, MKN-74.

DNA methylation dynamics are an important key to understanding various biological events, particularly regulation of gene expressions. To test the hypothesis that epidermal growth factor (EGF) signaling may influence DNA methylation status in cancer cells, which will show several altered biological characters compared with those before EGF-stimulation, we evaluated DNA methylation status with/without EGF-stimulation. The specific alteration of biological character in the gastric cancer cell line, MKN-74, by EGF was demonstrated by DNA synthesis, apoptosis and morphology, revealing that high concentrations of EGF (10 nM) altered the morphology accompanying a moderate increase of cell growth with induction of apoptosis, while low concentrations of EGF (0.1 nM) induced a high increase of cell growth without either morphological change or apoptosis. Although DNA synthesis is almost the same between 0.1 nM of EGF (164%) and 10 nM of EGF (172%), 0.1 nM of EGF showed higher methyltransferase activity than 10 nM of EGF did with a significant difference. In addition, the studies for both the methyl-base uptake into DNA incorporated with DNA synthesis and the methyl-base accepting capacity in DNA showed that a high concentration of EGF (10 nM) induced the demethylated status of the DNA compared with that of 0.1 nM EGF. Thus, we demonstrated that DNA methylation status is affected by EGF-stimulation with alteration of cell biological character.

Adenocarcinoma↗

The inhibitory effect of matrix metalloproteinase inhibitor ONO-4817 on lymph node metastasis in tongue carcinoma.

BACKGROUND: ONO-4817 is a novel matrix metalloproteinase (MMP) inhibitor which has a broad inhibitory spectrum for MMPs. We investigated the inhibitory effect of ONO-4817 on cervical lymph node metastasis of tongue carcinoma. MATERIALS AND METHODS: HSC-3-M3, a cell line derived from human tongue carcinoma with high metastatic potential for lymph node, was used. The direct cytotoxicity of ONO-4817 was assessed by MTT assay and the gelatinolytic activity by gelatin zymography and film in situ zymography (FIZ). The inhibitory effect on lymph node metastasis was examined by orthotopic implantation model with nude mice. RESULTS: ONO-4817 had no direct cyototoxicity on HSC-3-M3 cells. Gelatin zymography and FIZ demonstrated a suppression of MMP-9 activation and a marked inhibition of gelatinolysis. Additionally, a suppression of cervical lymph node metastasis was shown by therapeutic experiment. CONCLUSION: The MMP inhibitor, ONO-4817, is a candidate for adjunctive therapy of cervical lymph node metastasis in tongue carcinoma.

Animals↗

No cross-resistance of taxotere and taxol to conventional chemotherapeutic agents against gastric cancers as detected by MTT assay.

To evaluate the clinical usefulness of taxanes as antitumor agents, we compared the antitumor spectrum of taxanes with those of conventional antitumor agents against 88 fresh gastric cancer specimens by MTT assay. At cut-off concentrations of 100 micrograms/ml for taxotere (Docetaxel, DOC) and 300 micrograms/ml for taxol (Paclitaxel, PAC), both agents showed a higher efficacy rate than mitomycin C (MMC), cisplatin (CDDP) and 5-fluorouracil (5-FU) against the gastric cancer specimens. The patterns of antitumor activity of DOC and PAC were independent from those of the conventional agents, while the patterns of antitumor activity of the taxanes significantly correlated with each other. Conventional agent antitumor activity patterns tended to correlate with the patterns of other conventional agents. In conclusion, taxanes may be useful for clinical application against gastric cancer due to their different antitumor spectrum as compared to conventional agents.

Aged↗

Combination chemotherapy with JTE-522, a novel selective cyclooxygenase-2 inhibitor, and cisplatin against gastric cancer cell lines in vitro and in vivo.

COX-2 over-expression occurs in various cancers, but the role of COX-2 in cancer progression remains to be elucidated. We examined the inhibitory effects of a novel selective COX-2 inhibitor, JTE-522 (JT), against gastric cancer cell lines (TMK-1, MKN-45 and MKN-74) alone and in combination with cisplatin (CDDP). The antitumor activity of JTE-522 was evaluated by MTT assay, which revealed that JT alone elicits a dose-dependent antitumor activity in vitro. The JT/CDDP combination elicited a synergistic antitumor effect in MKN-45 cells and an additive effect in the other cell lines. In an in vivo study, 10 mg/kg JT and 12 mg/kg CDDP together elicited a synergistic antitumor activity against MKN-45 cells that were subcutaneously transplanted into nude mice. We conclude that JT is a potent antitumor agent in vitro and in vivo and that, in combination with CDDP, it might be a useful treatment strategy for gastric cancer.

Animals↗

TZT-1027 elucidates antitumor activity through direct cytotoxicity and selective blockade of blood supply.

BACKGROUND: TZT-1027 is a newly developed antitumor agent derived from dolastatin 10. MATERIALS AND METHODS: The in vitro activity of TZT-1027 on MCF-7 and R-27 cells was evaluated by MTT assay. TZT-1027 1 mg/kg/week was administered i.v. for 4 weeks into nude mice bearing MCF-7 and R-27. Subsequently, primary cultured cells from xenografts were also used for CD-DST. Two mg of TZT-1027 or 40 mg docetaxel per kg were injected i.v. into nude mice bearing R-27. 0.2% Evans blue was injected to assess the blood flow. RESULTS: TZT-1027 suppressed the in vitro growth of MCF-7 cells, while R-27 cells were resistant to TZT-1027, although its in vivo antitumor activity was remarkable. TZT-1027 blockaded R-27 tumor blood flow immediately after injection; blood flow was not affected by docetaxel. CONCLUSION: TZT-1027 exerts its antitumor activity through direct cytotoxicity against MCF-7 cells and through selective blockade of tumor blood flow against R-27 cells.

Animals↗

Thymidylate synthetase (TS) genotype and TS/dihydropyrimidine dehydrogenase mRNA level as an indicator in determining chemosensitivity to 5-fluorouracil in advanced gastric carcinoma.

BACKGROUND: One of the target enzymes of 5-fluorouracil (5-FU) is thymidylate synthetase (TS). The DNA sequence of the TS gene includes either double or triple tandem 28-bp repeats within the promoter region, such that TS genotypes can be classified as homozygous 3R/3R heterozygous 2R/3R or homozygous 2R/2R Several recent studies have shown that TS genotype affects mRNA expression, with 3R/3R homozygotes showing higher TS mRNA expression compared to the other genotypes. PURPOSE: We analyzed the TS genotype and TS and dihydropyrimidine dehydrogenase (DPD) mRNA expression levels in 22 advanced gastric carcinoma patients, and analyzed results with respect to patient 5-FU chemosensitivity, as detected by the tetrazolium-based colorimetric (MTT) assay and survival outcome. PATIENTS AND METHODS: Between September 2001 and April 2002, 22 Japanese patients with advanced gastric carcinoma were evaluated. Informed written consent was obtained from all patients and the study was approved by the ethical committee at our University Hospital Fresh surgical specimens from carcinoma lesions were enzymatically dissociated and incubated with 5-FU at a concentration of 50 microg/ml for 48 hours to determine the inhibition rate as detected by MTT assay. Normal and tumor tissue and peripheral blood samples were collected and stored at -80 degrees C until assay for TS genotype and TS and DPD mRNA level The TS genotype was assessed by PCR assay using peripheral monocytes, since monocyte genotypes represent the genotype of normal and tumor tissues. Quantification of TS and DPD mRNA levels was performed using real-time PCRP Survival outcome was assessed according to the disease-free survival period in cases with similar clinical backgrounds. RESULTS: TS genotyping revealed 19 3R/3R homozygotes and 3 2R/3R heterozygotes. After analysis of normal and tumor tissues, samples from homozygote 3R/3R cases showed higher TS mRNA expression than heterozygote 2R/3R cases, which was statistically significant at p<0.05. We also observed a statistically significant correlation in TS mRNA levels between normal and tumor tissues, while no significant correlation was observed for DPD mRNA levels between normal and tumor tissues. While no relationship between 5-FU chemosensitivity and TS genotype or mRNA expression was observed, cases with high DPD mRNA expression were resistant to 5-FU and exhibited poor survival outcomes. CONCLUSION: While TS genotype affected TS mRNA expression in both normal and tumor tissues in advanced gastric cancer, there is no relationship between TS genotype or mRNA expression level and 5-FU chemosensitivity. CONCLUSION: Our finding, that DPD mRNA expression appears to be a factor in determining 5-FU chemosensitivity and the survival outcome of advanced gastric cancer patients, is comparable with previous reports.

Aged↗

Cyclooxygenase-2 gene induction causes CDDP resistance in colon cancer cell line, HCT-15.

Drug resistance to cisplatin (CDDP) would represent a major obstacle for cancer therapy. The adenosine triphosphate (ATP) binding cassette (ABC) family of transport proteins, such as the 170 kDa P-glycoprotein (multidrug resistance gene-1; MDR-1) and the 190 kDa multidrug resistance-associated proteins (MRPs), are associated with multidrug resistance, including resistance to CDDP. The purpose of the present study was to investigate the relationship between cyclooxygenase-2 (COX-2) expression and the level of chemosensitivity to CDDP. We established the COX-2-overexpressed colon cancer cell line TR-5 from HCT-15 cells. We quantified the expression of m-RNA for MRP-1 and MDR-1 by a real-time PCR method, determining that the values of each gene/standardized GAPDH in HCT-15 and TR-5 were 23+/-0.4 and 6.1+/-0.5 in MRP-1 (p<0.02) and 9.0+/-4.8 and 3.6+/-0.5 in MDR-1, respectively. With respect to chemosensitivity, survival rates for 3 microg/ml and 10 microg/ml of CDDP were 81.5+/-12.2% and 26.1+/-11.7% (IC50=6.5 microg/ml) for HCT-15 and 96.6+/-1.7% and 77.4+/-4.9% (IC50=18.5 microg/ml) for TR-5, respectively, thus TR-5 showed higher resistance to CDDP than HCT-15 did with statistical differences. We also demonstrated a successful re-sensitization to CDDP toxicity in TR-5 by means of the COX-2 selective inhibitor JTE-522, 4-(4-cyclohexyl-2-methyl-1, 3-oxazol-5-yl)-2-fluorobenzene sulfonamide, which markedly decreased the IC50 of CDDP for TR-5 (from 17.3+/-2.6 microg/ml to 8.6+/-2.5 microg/ml). In conclusion, COX-2 overexpression induced increased MRP-1 expression in a colon cancer cell line, TR-5, resulting in chemoresistance to CDDP that was approximately triple the level of chemoresistance observed in the original HCT-15 cells line, as measured by calculation of the IC50. We also confirmed the efficacy of pretreatment of TR-5 cells with the COX-2 selective inhibitor JTE-522 in restoring chemosensitivity of these cells to CDDP, suggesting a strategy for overcoming drug resistance to CDDP.

ATP Binding Cassette Transporter, Subfamily B, Mem↗