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Yoshihide Otani

Publications and source records attributed to Yoshihide Otani.

At least 37 records · Page 2Linked to original sources
PubMed2004

Diagnosis and treatment of a gastric hamartomatous inverted polyp: report of a case.

Gastric hamartomatous polyps are rare and difficult to diagnose. We report the case of a 43-year-old woman admitted to our hospital after an upper gastrointestinal series revealed a submucosal tumor. Upper gastrointestinal endoscopy showed a submucosal tumor (SMT), which was eroded with a depression on its surface, in the upper corpus. Endoscopic ultrasonography showed a heterogeneous tumor in the third layer. A laparoscopic wedge resection of the stomach allowed us to perform complete resection of the tumor, which measured 2.8 cm in diameter. The pathological diagnosis was a gastric hamartomatous inverted polyp. The postoperative course was uneventful. Only 27 cases of gastric hamartomatous polyps have been reported in Japan. Hamartomatous inverted polyps without a stalk are classified as the "SMT type" because the tumor is inverted into the submucosal layer, whereas polyps with a stalk are classified as the "polyp type." All of the polyps in past reports were resected endoscopically; however, laparoscopic wedge resection may be indicated for SMT-type hamartomatous inverted polyps larger than 2.0 cm in diameter.

Adult↗
PubMed2004

Clinical and pathological disappearance of peritoneal dissemination in a patient with advanced gastric cancer receiving chemotherapy with S-1 and low-dose cisplatin.

A 54-year-old woman with severe abdominal distention suffered from massive ascites. Cytological examination revealed adenocarcinoma cells, leading to a diagnosis of peritonitis carcinomatosa. Gastrointestinal fiberscopy (GIF) resulted in a histological diagnosis of type 4 advanced gastric cancer with signet-ring cell carcinoma. The clinical diagnosis was confirmed to be cT3(SE)cN1cM0cH0cP1, cStage IV gastric cancer, type 4, according to the Japanese classification of gastric carcinoma. The patient was treated with S-1 and low-dose cisplatin (CDDP) in order to alleviate the critical state of the disease. After the third cycle of the regimen, the clinical response of P1 was classified as a partial response (PR) according to the World Health Organization (WHO) criteria. The patient's appetite loss and abdominal discomfort were markedly alleviated. The patient experienced grade 2 leukocytopenia throughout the regimen. Surgery was performed. Ascites and peritoneal disseminated lesions were not observed, and cytological examination of the peritoneal washes was negative. Total gastrectomy with D1 lymph node dissection was performed, and the surgical diagnosis was sT3(SE)sN0sM0sH0sP0; sStage II. Microscopically, viable cancer cells were found to be scattered throughout the subserosal-serosal layers in the resected stomach. All of the samples from lesions that were potentially cancers involving peritoneal dissemination were diagnosed as fibrous scar tissues without any viable cancer cells. The patient is alive without recurrence at 10 months after surgery and 14 months after the initial chemotherapy. Thus, systemic chemotherapy with S-1/low-dose CDDP achieved desirable control of peritoneal disseminated cells, as assessed microscopically, suggesting that the regimen may be an effective strategy for the treatment of advanced gastric cancer with peritonitis carcinomatosa.

Ascites↗
PubMed2004

Differences between scirrhous and non-scirrhous human gastric carcinomas from the aspect of proMMP-2 activation regulated by TIMP-3.

Gastric carcinomas can be classified into scirrhous carcinomas (SC), i.e. 'linitis plastica' or Borrmann 4 gastric cancer, and non-scirrhous carcinomas (NSC). SC are characterized by diffuse invasive growth patterns with marked fibrosis, frequent peritoneal dissemination and lymph-node metastases and poor prognosis, while NSC show medullary growth patterns and common hematogenous metastases. To study the differences in local expression levels of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) between SC and NSC, we examined the expression of MMPs and TIMPs in human gastric carcinoma tissues by several methods including sandwich-enzyme immunoassay systems, gelatin zymography, reverse transcriptase-polymerase chain reaction (RT-PCR), real-time quantitative PCR, immunoblotting, immunohistochemistry and in situ zymography. Of the seven MMPs and two TIMPs tested, only proMMP-2 levels were remarkably higher in SC than in NSC (P < 0.01), and proMMP-2 activation ratio was significantly lower in SC than in NSC (P < 0.05). TIMP-3 mRNA levels were remarkably about 2-fold higher in SC than in NSC tissues (P < 0.01). TIMP-3 production in SC was confirmed by immunoblotting and TIMP-3 was immunolocalized to stromal fibroblasts in SC. TIMP-3 mRNA levels inversely correlated with proMMP-2 activation ratios, although the expression levels of MT1-MMP and MT2-MMP were not different in SC and NSC. By in situ zymography, gelatinolytic activity appeared to be weaker in SC than in NSC. All these data suggest that proMMP-2 activation is down-regulated by TIMP-3 expressed in scirrhous gastric carcinomas. Our findings may explain the differences in clinical behaviors of SC and NSC.

Adenocarcinoma, Scirrhous↗
PubMed2004

Docetaxel enhances the cytotoxicity of cisplatin to gastric cancer cells by modification of intracellular platinum metabolism.

We have examined the combined anticancer effects of docetaxel (DOC) and cisplatin (CDDP) in vitro using the gastric cancer cell lines MKN-45, MKN-74, and TMK-1. Treatment of the cell lines with 30 microg/ml of DOC for 24 h followed by incubation with 3 or 10 microg/ml of CDDP for 24 h showed a clear synergistic effect. Sequence dependency of the agents was observed in these cell lines: DOC followed by CDDP (DC) showed a stronger antitumor effect than CDDP followed by DOC (CD) in all cell lines. To clarify the mechanism of action of the DC combination, total intracellular platinum (Pt) levels were evaluated after treatment with CDDP alone or combined with DC. For the MKN-45 and -74 cell lines, cells treated with DOC (10 microg/ml for 12 h) and then CDDP showed significantly increased intracellular Pt accumulation compared to cells treated with CDDP alone. We also investigated alterations in intracellular glutathione (GSH) concentration in response to DOC and CDDP. MKN-45 and -74 cells pretreated with DOC (10 microg/ml for 12 h) showed significantly increased intracellular GSH levels compared to cells administered CDDP only. To explain these findings, messenger RNA (mRNA) levels for multidrug resistance-associated protein-1 (MRP-1), the ATP-dependent pump for Pt-GSH complexes, were quantified in CDDP-treated MKN-45 cells with and without DOC pretreatment. While CDDP administration increased MRP-1 mRNA expression in MKN-45 cells, MRP-1 was not up-regulated after CDDP administration in DOC pretreated MKN-45 cells. Our results suggested that the enhanced CDDP toxicity due to DOC pretreatment may be related to the accumulation of intracellular Pt-GSH complexes, because DOC appears to suppress the MRP-1 up-regulation induced by CDDP exposure in gastric cancer cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2004

Inhibition of DNA methyltransferase by antisense oligodeoxynucleotide modifies cell characteristics in gastric cancer cell lines.

DNA (cytosine-5-)-methyltransferase 1 (DNMT1) plays an important role in the maintenance of DNA methylation patterns via complicated networks including signaling pathways and transcriptional factors, relating to cell differentiation or carcinogenesis. In the present study, we designed an antisense oligodeoxynucleotide of DNMT1 (AS/MT: 5'-CGGTAC GCGCCGGCATCT-3') and demonstrated successful inhibition of DNMT1 expression by AS/MT at the protein level, using gastric cancer cell lines in vitro. E-cadherin protein expression was increased, and both cyclin D1 and PCNA were decreased by AS/MT treatment. AS/MT also induced suppression of cell growth as determined by BrDU uptake incorporation, in a dose-dependent manner, suggesting specificity of AS/MT. Simultaneously, morphological alterations were observed in both TMK-1 and MKN-45 cells after 24 h incubation with 2 micro M of AS/MT. The cells changed shape from their original forms to dispersed, fibroblast-like cells with neurite-like processes, accompanied by an increased adhesive potential of the cells. An in vivo model of peritoneal dissemination using the nude mouse system showed an increased malignant potential of AS/MT treated TMK-1 cells as demonstrated by a greater number of peritoneal tumor nodules in the AS/MT as compared to the NS/MT treated group, 34.8+/-4.3 vs. 22.4+/-3.0 nodules, respectively (p=0.0039). The total wet tumor weight in the AS/MT group (350+/-47.4 g) was significantly greater than that in the NS/MT group (248+/-41.5 g) (p=0.0065). In conclusion, the inhibition of DNA methylation by DNMT1 by an antisense oligodeoxynucleotide influences cell morphology and adhesion, as well as cell growth in gastric cancer cells in vitro. Moreover, these alterations in the characteristics of cancer cells resulted in an increased ability to attach onto the peritoneum in the nude mouse system in vivo, suggesting that strict clinical guidelines will be necessary to utilize such a DNA methylation inhibitor, since it does not always mean a therapeutic antitumor strategy.

Adenocarcinoma↗
PubMed2003

Chemosensitivity testing--present and future in Japan.

Radical surgery with extended lymph node dissection is the first and only curative treatment of gastrointestinal cancer. Although the combined cancer chemotherapy has achieved 30%-50% response rates, a controversy still remains over the significance of the adjuvant cancer chemotherapy after surgery. To break through this limitation, we have introduced the chemosensitivity test to evaluate the appropriate adjuvant cancer chemotherapy for advanced gastrointestinal cancer. Our plural studies indicated that the chemosensitivity test would be useful in evaluating the appropriated adjuvant chemotherapy by increasing survival in the sensitive group. Recently, the molecular targets have been clarified for the conventionally available antitumor agents, e.g., thymidylate synthetase for 5-fluorouracil, ATP-binding cassette transporters for anthracyclines, glutathione-related detoxification for platins, and topoisomerase I for CPT-11, which will be applied for dinical use in evaluating the appropriate cancer chemotherapy. The chemosensitivity test is approved as "advanced clinical medicine" by the Japanese Ministry of Health, Welfare, and Labor in five institutes at present. Because complete dissection and chemosensitivity test-guided adjuvant chemotherapy will result in a survival benefit for patients with advanced gastrointestinal cancer, this test should be approved as "social insurance" for further wide clinical application.

Antineoplastic Agents↗
PubMed2003

Complete response of a highly advanced gastric carcinoma to preoperative chemoradiotherapy with S-1 and low-dose cisplatin.

S-1 has been developed as a new oral anticancer drug, based on the biological modulation of 5-fluorouracil. We report a patient with highly advanced gastric carcinoma who was treated successfully with a new combination chemoradiotherapy using S-1 and cisplatin (CDDP). The patient was a 37-year-old man who was diagnosed with advanced gastric carcinoma (T4N3M0) that had invaded the diaphragm and the paraaortic tissues. Remarkable tumor reduction was observed in the primary tumor and metastatic lymph nodes around the stomach after three cycles of the therapy. Radiological examination before surgery determined that a partial response (PR) had been achieved by the initial therapy. Adverse effects included only a gastrointestinal disorder that was limited to grade 2 when low-dose CDDP was utilized in the regimen, while an initial high dose of CDDP resulted in grade 3 toxicity, due to myelosuppression. The patient underwent curative surgery, including total gastrectomy, D2 lymph node dissection, and splenectomy, after completion of the radiochemotherapy regimen. No surgical complication was observed. No tumor cells were detected by pathological evaluation of the resected stomach and all the regional lymph nodes, confirming a pathological complete response (CR; grade 3). This regimen is a potent treatment for advanced gastric carcinoma, especially when used as preoperative chemotherapy to control cancer cells.

Adult↗
PubMed2003

Gastric carcinoid tumors with aggressive lymphovascular invasion and lymph node metastasis.

We report a patient with multiple gastric carcinoid tumors without hypergastrinemia. An abdominal computed tomography (CT) scan was performed in a 66-year-old Japanese man who had abdominal discomfort. An abnormal, round, 2.5 cm mass close to the lesser curvature of the stomach was detected. Multiple small gastric carcinoid tumors were also detected by endoscopy. A total gastrectomy with lymph node dissection was performed after it was determined that the round mass was a lymph node metastasis of carcinoid tumor. Further pathological investigation of the surgical specimen revealed multiple gastric carcinoid tumors with severe lymphovascular invasion. The carcinoid tumors in the present patient were not related to hypergastrinemia. These lesions could not be grouped as any of the three types of gastric carcinoid tumors in the recent classification. Furthermore, as a simple distal gastrectomy is the standard treatment for multiple carcinoid tumors of the stomach, we recommend that a precise histopathological evaluation should be performed before an appropriate curative surgical treatment is selected.

Abdominal Pain↗
PubMed2003

Reduced angiogenesis in peritoneal dissemination of gastric cancer through gelatinase inhibition.

Marimastat is a broad-spectrum matrix metalloproteinase (MMP) inhibitor that inhibits almost all major MMPs, key enzymes in gastric cancer invasion and metastasis. We investigated the ability of marimastat to inhibit tumor angiogenesis in the severe combined immuno-deficient (SCID) mouse/human gastric cancer model of peritoneal dissemination. A human stomach adenocarcinoma cell line, TMK-1, was injected intraperitoneally into SCID mice. On the 7th day after tumor inoculation, the administration of marimastat (27 mg/kg/day) was initiated and the treatment was continued for 2 weeks using subcutaneously-inoculating mini-osmotic pumps. On the 21st day, the mice were killed and the disseminated nodules were evaluated. Total weights, numbers, and the microvascular density of the disseminating nodules were significantly lower in mice treated with marimastat compared to the control group. Film in situ zymography demonstrated that net gelatinolytic activity in the tissues was weaker in treated-group nodules than in control-group nodules. Thus, our results suggested that marimastat inhibited peritoneal dissemination of human gastric cancer cells through inhibition of tumor angiogenesis, possibly involving the down-regulation of gelatinases, in SCID mice injected with human gastric cancer cells.

Animals↗
PubMed2003

Histological complete response in a case of advanced gastric cancer treated by chemotherapy with S-1 plus low-dose cisplatin and radiation.

A 76-year-old male was diagnosed with stage IV (cT4, cN2, cP0, cH0, cM0) gastric carcinoma with a type 3 tumor in the cardia with lymph node metastases, determined by gastrofiberscope and abdominal computed tomography (CT). The patient was treated with chemotherapy consisting of S-1 and low-dose cisplatin (CDDP) during the first cycle (3 weeks). S-1 was orally administered at a dose of 100 mg/day (60 mg/m(2)/day) on days 1-21. CDDP was infused at a dose of 10 mg/day (6 mg/m(2)/day) on days 1-5, 8-12 and 15-19. After this cycle, the clinical response was evaluated as no change (NC). In the second cycle, radiation therapy (2 Gy/day for 5 days/week) was initiated along with the chemotherapy. The CDDP dose was decreased to 7.5 mg/day because of the grade 3 thrombocytopenia and grade 2 leukocytopenia that occurred during the first cycle. The second cycle was stopped at a total radiation dose of 48 Gy due to grade 3 thrombocytopenia and grade 2 leukocytopenia. Examination after this treatment showed remarkable reduction of tumor volume in the primary lesion and lymph nodes, which was defined as a partial response (PR). The patient then underwent total gastrectomy with D1 lymph node dissection. The postoperative course was uneventful without surgical complications. At this time, no gastric cancer cells were detected in the resected specimen, including the primary lesion and lymph nodes, confirming a pathological complete response (CR grade 3). Thus, the chemo-radiation treatment regimen described here may be a potent tool to control advanced gastric carcinoma.

Aged↗
PubMed2003

Possible chemoresistance-related genes for gastric cancer detected by cDNA microarray.

To identify chemoresistance-related genes of gastric cancer, we utilized cDNA microarray technology. Thirty-five gastric cancer specimens surgically resected at our institute between 1998 and 1999 were studied for quantification of expression of 6300 genes by means of oligonucleotide microarray methods, and the results were evaluated in comparison with the chemoresistance of the specimens, which was determined by MTT (tetrazolium-based 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Inhibition rates (IR) were determined for cisplatin (DDP), 5-fluorouracil (5-FU), mitomycin C or doxorubicin. IR of 60% or more was regarded as sensitive to each agent, and IR of less than 40% was defined as resistant. Clustering was successfully completed for DDP, resulting in selection of 23 candidates as DDP-resistance-related genes, including vascular permeability factor, 2 membrane transporting subunits, and retinoblastoma-binding protein-1. In addition, further selection of DDP-resistance-related genes was performed according to these criteria: 1) Expression of the gene can be detected in more than 70% of resistant tumors. 2) Expression can be detected in less than 30% of sensitive tumors. 3) Expression in tumors is more than twice that of normal mucosa in more than 50% of specimens. Then, metallothionein-IG and heparin-binding epidermal growth factor-like growth factor (HB-EGF) were identified as candidate DDP-resistance-related genes. When known DDP-resistance-related genes were analyzed according to the MTT assay result, families of glutathione-S-transferase and cyclooxygenase-2 genes were also evaluated as resistance-related genes. For 5-FU resistance, dihydropyrimidine dehydrogenase and HB-EGF-like growth factor genes were also suggested to be resistance-related genes. The present study demonstrated that oligonucleotide microarrays can provide information regarding chemoresistance factors in cancer.

Antineoplastic Agents↗
PubMed2003

A possible defensive mechanism in the basal region of gastric mucosa and the healing of erosions.

A possible defensive mechanism in the basal region of the gastric mucosa was hypothesized in the present study. In vivo microscopy was performed to observe the basal region after thermal injury to the back skin of rats. A donor of nitric oxide, 3-morpholinosydnonimine hydrochloride (SIN-1), or a serine protease inhibitor, camostat mesilate, was administered. Anti-vascular endothelial growth factor (VEGF) neutralizing antibody was administered 5 hours after thermal injury (anti-VEGF group). Post-capillary venules could be observed in the basal region of the gastric mucosa (PV-BGM). The PV-BGM was dilated 5 hours after thermal injury, and it was reduced by the administration of SIN-1 or pre-treatment with camostat mesilate. In the control group, the erosions did not reach the basal region of the gastric mucosa. Most of the erosions healed within 72 hours. Delayed healing was observed in the anti-VEGF group. In this group, exudation and congestion in the basal region were observed at 24 hours, and ulcer formation was observed at 72 hours after thermal injury. It is thus hypothesized that blood flow of the PV-BGM increases when superficial mucosal circulation is disturbed. The PV-BGM can contribute to defensive mechanisms in the basal region of gastric mucosa. The abnormal healing process may disturb the defensive mechanism at the base of the gastric mucosa, thereby resulting in ulcer formation.

Animals↗
PubMed2002

Rare case of early mucosal gastric cancer presenting with metastasis to the bulbar conjunctiva.

Early gastric cancer has an excellent outcome following surgical treatment. In particular, mucosal gastric cancer (m-cancer) very rarely results in metastatic dissemination and may be successfully treated by local surgical resection. We report a 64-year-old Japanese woman who presented with a recurrent cystic lesion on the left bulbar conjunctiva, with a biopsy specimen revealing metastatic signet-ring cell carcinoma. Gastrointestinal investigations revealed an early gastric cancer in the lesser curvature of the stomach. Biopsy specimen of the gastric lesion indicated poorly differentiated adenocarcinoma, which was identical to findings in the lesion in the bulbar conjunctiva. She underwent a distal gastrectomy and made an uneventful recovery. Histopathological analysis indicated a gastric signet-ring cell carcinoma that was limited to the mucosal layer, without evidence of lymphatic spread. Although the exact mechanism of metastatic dissemination to the bulbar conjunctiva is unclear, this case is very unusual, because ocular metastases almost invariably occur in the context of documented and established malignant disease. This is, to our knowledge, the first reported case of a patient with gastric mucosal cancer who presented with a conjunctival metastatic deposit and who subsequently received curative surgical treatment for both conditions.

Adenocarcinoma↗
PubMed2002

Minimally invasive surgery for gastric carcinoid tumor.

Minimally invasive laparoscopic wedge resection for gastric mucosal carcinoma and submucosal tumor was first performed in Keio University hospital in 1992. Since then, 172 gastric tumor patients, including four cases of carcinoid tumor, have been successfully treated at the Keio University hospital using this procedure. No local disease recurrence or distant metastases have been observed in follow-ups over as long as 10 years. Chronic atrophic gastritis patients with carcinoid tumors occurring secondary to hypergastrinemia are candidates for the minimally invasive surgery. With careful patient selection according to tumor size, depth of invasion, and histopathological findings of malignancy grade, endoscopic and laparoscopic therapy for these patients can be a safe, curative, and minimally invasive procedure.

Carcinoid Tumor↗