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H Tabara

Publications and source records attributed to H Tabara.

At least 19 recordsLinked to original sources
PubMed2001

Enhanced apoptosis and transforming growth factor-beta1 expression in colorectal adenomas and carcinomas after Sulindac therapy.

PURPOSE: We tried to elucidate the effects of sulindac on human colorectal carcinoma. METHODS: Sulindac (300 mg/day) was administered for two weeks before operation to 33 patients with sporadic colorectal carcinoma (Sulindac Group). Resected specimens were used to detect apoptosis by terminal dUTP nick end labeling and transforming growth factor (TGF)-beta1 expression by immunohistochemistry. The results were compared with those from the historical Control Group. Twenty-nine available preoperative biopsies taken from carcinomas before sulindac prescription and 22 concurrent colorectal adenomas (9 and 13 in Sulindac and Control Groups, respectively) in the resected specimen were also examined regarding TGF-beta1 expression. RESULTS: In the resected carcinomas and adenomas, more frequent apoptosis and higher TGF-beta1 scores were observed in the Sulindac Group than in the Control Group. Overexpression of TGF-beta1 and apoptosis occurred in the same region in adenomas but not in carcinomas. A positive correlation between TGF-beta1 scores and apoptotic frequency was found in adenomas (P = 0.01, rho = 0.91) but not in carcinomas (P = 0.89, rho = 0.03). CONCLUSION: We conclude that sulindac induces apoptosis in human colorectal carcinomas as well as in adenomas. Also, one of the antineoplastic effects of sulindac might be mediated by upregulating TGF-beta1 expression, particularly in colorectal adenomas.

Adenoma↗
PubMed2001

Concurrent expression of angiogenic growth factors and neovascularization during tumourigenesis in colorectal carcinoma patients.

Details of concurrent expression of angiogenic growth factors (AGFs) and microvessel density (MVD) in human colorectal adenomas and carcinomas remain obscure. Eighty lesions, 20 each from colorectal adenoma, Tis, T1 and T2 cancers were evaluated immunohistochemically for basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), thymidine phosphorylase (dThdPase) and MVD. MVD (p = 0.0001) and bFGF expression (p = 0.0001) increased in the order of adenoma, Tis, T1 and T2 cancers. VEGF expression was same in adenomas and cancers while dThdPase was weak in adenomas but strongly expressed in invasive carcinomas ( > T1). MVD had positive correlation with tumour size in small (< or = 4 cm) colorectal cancers. Concurrent expression of AGFs was noticed in invasive carcinomas. bFGF seems to be the strongest among the three AGFs expressed during colorectal carcinogenesis and had a significant correlation with tumour MVD. Concurrent expression of multiple AGFs is a crucial step in the transition from non-invasive to invasive carcinoma.

Adenocarcinoma↗
PubMed2000

Genetic requirements for inheritance of RNAi in C. elegans.

In Caenorhabditis elegans, the introduction of double-stranded RNA triggers sequence-specific genetic interference (RNAi) that is transmitted to offspring. The inheritance properties associated with this phenomenon were examined. Transmission of the interference effect occurred through a dominant extragenic agent. The wild-type activities of the RNAi pathway genes rde-1 and rde-4 were required for the formation of this interfering agent but were not needed for interference thereafter. In contrast, the rde-2 and mut-7 genes were required downstream for interference. These findings provide evidence for germ line transmission of an extragenic sequence-specific silencing factor and implicate rde-1 and rde-4 in the formation of the inherited agent.

Animals↗
PubMed2000

Concurrent expressions of metallothionein, glutathione S-transferase-pi, and P-glycoprotein in colorectal cancers.

PURPOSE: Because the status of the inherent drug-resistance of colorectal cancers remains obscure, human colorectal cancers with no neoadjuvant therapy were retrospectively investigated regarding the expression of three drug-resistant proteins: metallothionein, glutathione S-transferase-pi, and P-glycoprotein. METHODS: Paraffin-embedded tissues of 130 colorectal cancers (Dukes A, 20; B, 49; C, 41; D, 20) obtained by surgical resections from 1982 to 1989 were used. The three proteins were immunostained by the streptavidin-biotin complex method. The immunostaining was judged to be positive if more than 5 percent of cells showed positive staining by use of cell analysis system. The data were compared with clinicopathologic features (Dukes A-D) and patients' prognosis (Dukes AC). RESULTS: Metallothionein, glutathione S-transferase-pi, and P-glycoprotein were positively expressed in 91 (70 percent), 30 (23 percent), and 98 (75 percent), respectively. A total of 120 (86 percent) expressed at least one drug-resistant protein. No intergroup differences were observed between positive and negative expressions of the proteins and their clinicopathologic features except tumor location. Rectal cancers positively expressed P-glycoprotein and three proteins more frequently. Twenty-six (20 percent), 65 (50 percent), and 21 (16 percent) cancers positively expressed one, two, and three proteins, respectively. The disease-free survival rates of patients with Dukes A through C cancer with positive staining for one, two, and three proteins were 100, 94, and 83 percent (at 1 year); 100, 72, and 51 percent (at 3 years); and 94, 66, and 38 percent (at 5 years), respectively (Kaplan-Meier with log-rank test; P = 0.016). In the multivariate Cox analysis, age, Dukes stage, tumor size, and glutathione S-transferase-pi were independent prognostic factors. CONCLUSIONS: The patients with concurrent expression of drug-resistant proteins in their cancers had worse prognoses. Examining drug-resistant proteins in colorectal cancers may be useful in selecting adjuvant chemotherapy and in predicting prognosis more accurately.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Long-term survival of transmural advanced gastric carcinoma following curative resection: multivariate analysis of prognostic factors.

Patients with transmural (T2N0-T3N2) advanced gastric carcinoma comprise the largest group with uncertain outcome. These patients must be stratified according to the prognostic variables so the high risk group can be precisely identified. A total of 152 patients with transmural advanced gastric carcinomas were uniformly treated with a curative intent between 1979 and 1989 with at least a 7-year follow-up. Results and prognostic factors of long-term survival were analyzed by univariate and multivariate analyses. Seventy-five (49%) patients with advanced gastric carcinoma survived more than 7 years, which indicates the curative nature of surgery for gastric carcinoma. Seventeen variables were evaluated by univariate analysis. In the multivariate analysis, patient's age [>70 years, relative risk (RR) 2.4)], intraoperative blood loss (>500 ml, RR 1.7), blood vessel invasion (RR 2.3), ratio of invaded dissected lymph nodes (>0.2, RR 3.0), and tumors penetrating the serosa (RR 3.9) were the independent prognostic variables. The results of this study indicate that extensive lymphadenectomy and minimal intraoperative blood loss might be helpful for improving patient survival following a curative resection. Patients with vessel invasion, serosal involvement, and those >70 years of age should be considered at high risk and require appropriate adjuvant therapy to prolong survival.

Adenocarcinoma↗
PubMed2000

Gastric resection in the aged (> or = 80 years) with gastric carcinoma: a multivariate analysis of prognostic factors.

BACKGROUND: The incidence of gastric neoplasm is increasing in the elderly population. Therefore, a rational method of treatment for gastric cancer in the elderly should be constituted to improve the survival. The purpose of the present study was to clarify whether the patient's age is an independent prognostic factor and to determine clinicopathological characteristics in the elderly. METHODS: Curative resection of gastric cancer was carried out on 601 patients who were 40 years or older. They were divided into the following two groups: younger patients (between 40 and 79 years old) and elderly patients (80 years or older). The clinicopathologic features of these patients were reviewed retrospectively and multivariate analysis was carried out. RESULTS: The distinguishing features of gastric cancer in the elderly patients were intestinal and mixed types of cancer, distal third stomach dominance in the tumour location, advanced stage of disease, and a low rate of extensive lymph node dissection (D3 or more). Regarding the recurrence site, the liver was the dominant site in the elderly group (25.3% in the younger group vs 54.5% in the elderly group). The 10-year disease-free survival rate of the elderly group was 53.2%, which was significantly worse than that (79.9%) of the younger patients (P = 0.0004). In multivariate analysis, an age of > or = 80 years is an independent prognostic factor, as well as stage, depth of tumour invasion, lymph node metastasis, scirrhous carcinoma, and blood transfusion. CONCLUSIONS: Results indicate that gastric cancer in elderly patients has a poorer prognosis than that in younger patients.

Adult↗
PubMed2000

Body mass index determines the success of lymph node dissection and predicts the outcome of gastric carcinoma patients.

We tried to determine the role of the body mass index (BMI) on the extent of lymph node dissection in gastric cancer surgery. Seven hundred and eighty-seven patients with gastric carcinoma were reviewed. Ninety-two (11%) patients exceeded the upper limit of the optimum BMI. Significantly fewer lymph nodes were removed following D2 (p = 0.002) and >/=D3 (p = 0.023) dissections, and the lymph node ratio was significantly (p = 0.0383) higher in overweight patients. The recurrence-free survival was significantly (p = 0.0297) shorter in T2/T3 cases with high BMI, and BMI (relative risk 1.85) became an independent prognostic factor in multivariate analysis. Higher BMI hampers regional lymph node dissection in gastric cancer patients and became an independent predictor of disease recurrences in T2/T3 gastric cancers.

Aged↗
PubMed1999

The rde-1 gene, RNA interference, and transposon silencing in C. elegans.

Double-stranded (ds) RNA can induce sequence-specific inhibition of gene function in several organisms. However, both the mechanism and the physiological role of the interference process remain mysterious. In order to study the interference process, we have selected C. elegans mutants resistant to dsRNA-mediated interference (RNAi). Two loci, rde-1 and rde-4, are defined by mutants strongly resistant to RNAi but with no obvious defects in growth or development. We show that rde-1 is a member of the piwi/sting/argonaute/zwille/eIF2C gene family conserved from plants to vertebrates. Interestingly, several, but not all, RNAi-deficient strains exhibit mobilization of the endogenous transposons. We discuss implications for the mechanism of RNAi and the possibility that one natural function of RNAi is transposon silencing.

Amino Acid Sequence↗
PubMed1999

Prognostic factors in T1 and T2 squamous cell carcinoma of the thoracic esophagus.

BACKGROUND: Prognostic indicators in patients with T2 tumor have not been fully understood. OBJECTIVE: To clarify the clinicopathologic characteristics and long-term results of T1 and T2 squamous cell carcinomas of the thoracic esophagus. DESIGN: Consecutive case series. SETTING: Department of surgery in a university hospital. PATIENTS: Of 234 patients with primary squamous cell carcinoma of the thoracic esophagus, 142 patients underwent esophagectomy with curative intent: 97 patients had pT1 and pT2 tumors. INTERVENTIONS: Investigated were clinicopathologic characteristics of 65 of 97 patients with pT1 and pT2 tumors; excluded were 7 patients who died of postoperative complications and another 25 patients who died of causes other than esophageal cancer. MAIN OUTCOME MEASURES: Clinicopathologic characteristics and long-term results. RESULTS: Pathologic tumor stages were pT1 N0 in 23 patients, pT1 N(+) in 7 patients, pT2 N0 in 15 patients, and pT2 N(+) in 20 patients. Fifty patients are alive and free of cancer and 15 patients died of tumor recurrence (1 patient with pT1 N0 tumor, 1 patient with pT1 N[+][+] tumor, 1 patient with pT2 N0 tumor, and 12 patients with pT2 N[+] tumor). The sites of metastatic nodes in 6 survivors with pT1 N(+) tumor were a solitary perigastric node in 4 patients, a solitary mediastinal node in 1 patient, and 2 mediastinal nodes in 1 patient. The 5-year survival rates of patients with pT1 N0, pT1 N(+), and pT2 N0 tumors all exceeded 85%, and the rate of those with pT2 N(+) tumor was 33.9% (pT2 N[+] vs. others: pT1 N0, pT1 N[+], and pT2 N0; P = .003). The factors affecting survival rate by univariate analysis were Borrmann classification (0, 1 vs. 2, 3, 4), tumor size (<4.0 vs. > or =4.0 cm), combined T, N factor (pT2 N[+] vs. others), time of operation (< or =420 vs. >420 minutes), estimated blood loss (<1000 vs. > or =1000 mL), and lymph vessel invasion (marked vs. not marked). Stage pT2 N(+) tumor became a single independent prognostic factor for survival as determined by multivariate analysis (pT2 N[+] vs. others; P = .008). CONCLUSIONS: Stage pT1 N(+) tumors with a few diseased nodes and pT2 N0 tumors are considered to be a group with an excellent prognosis, similar to pT1 N0 tumors. Patients with pT2 N(+) diseases had worse prognoses and thus should have meticulous lymph node dissection and extensive adjuvant therapy.

Aged↗
PubMed1999

Prognostic significance of perioperative blood transfusions in resectable thoracic esophageal cancer.

OBJECTIVE: The perioperative blood transfusions have been associated with tumor recurrence and decreased survival in various types of alimentary tract cancer. There exist, however, contradictory studies showing no relationship between blood transfusions and survival. For patients with esophageal cancer, only one report suggested that blood transfusions did not by itself decrease the chance of cure after esophagectomy. METHODS: Among 235 patients with primary squamous cell carcinoma of the thoracic esophagus between December 1979 and March 1998, 143 patients (60.9%) underwent esophagectomy with curative intent (RO). To exclude the effects of surgery-related postoperative complications, 14 patients who died within 90 days during the hospital stay were excluded. Thus, clinicopathological characteristics and prognostic factors were retrospectively investigated between patients with no or few transfusions (< or = 2 units) (n = 58), and much transfused patients (> or = 3 units) (n = 71). RESULTS: Sixty-three patients are alive and free of cancer, and 66 patients are dead. A total of 98 patients (76%) received blood transfusions, whereas 31 patients (24%) had no transfusion. The amount of blood transfused was 1 or 2 units in 27 patients (27.6%), 3 or 4 units in 33 (33.7%), 5 or 6 units in 20 (20.4%), and > or = 7 units in 18 (18.4%). The 5-yr survival rate for patients with no or few transfusions was 69%, whereas that for much transfused patients was 31.7% (p < 0.0001). The much transfused patients had more prominent ulcerative tumor, longer time of operation, more estimated blood loss, and more marked blood vessel invasion than the group with no or few transfusions. The factors influencing survival rate were tumor location, Borrmann classification, size of tumor, depth of invasion, number of lymph node metastases, time of operation, amount of blood transfusions, lymph vessel invasion, and blood vessel invasion. Among those nine significant variables verified by univariate analysis, independent prognostic factors for survival determined by multivariate analysis were number of lymph node metastasis (0 or 1 vs > or = 2, p < 0.0001), amount of blood transfusions (< or = 2 units vs > or = 3 units, p < 0.0001), and blood vessel invasion (marked vs non-marked, p = 0.0207). CONCLUSIONS: There is an association between high amount of blood transfusions and decreased survival for patients with resectable esophageal cancer. To improve the prognosis, surgeons must be careful to reduce blood loss during esophagectomy with extensive lymph node dissection and subsequently must minimize blood transfusions.

Aged↗
PubMed1999

nm23 in the primary and metastatic sites of gastric carcinoma. Relation to AFP-producing carcinoma.

Tumor metastasis is the major cause of treatment failure and death in cancer patients. The present study was designed to extrapolate the association of nm23 expression with acquisition of metastatic potential of gastric carcinoma with special reference to the alpha-fetoprotein-producing gastric carcinoma (APGC). The primary tumor with surrounding normal mucosa and metastatic lymph nodes of 30 patients with APGC and 29 randomly selected matched controls of non-AFP gastric carcinoma (NAGC) were immunostained for nm23 and an image analyzer system was used for quantitative evaluation. Overexpression of nm23 was noted in 71% (42/59) of the primary tumors and 18% (10/55) of the metastatic tumors and there was no difference between the APGC and NAGC groups. The overexpression of nm23 in the primary tumors correlated with tumor invasion, metastasis and progression in all cases and similar results were obtained in the APGC and NAGC groups except for the tumor stage which was insignificant in the APGC group. The patient survival was adversely affected by the overexpression of nm23 in the primary sites and downregulation in the metastatic sites in all cases but lost their significance in the multivariate analysis. However, nm23 status did not affect patient survival in the APGC group.

Aged↗
PubMed1999

pos-1 encodes a cytoplasmic zinc-finger protein essential for germline specification in C. elegans.

Germ cells arise during early C. elegans embryogenesis from an invariant sequence of asymmetric divisions that separate germ cell precursors from somatic precursors. We show that maternal-effect lethal mutations in the gene pos-1 cause germ cell precursors to inappropriately adopt somatic cell fates. During early embryogenesis, pos-1 mRNA and POS-1 protein are present predominantly in the germ precursors. POS-1 is a novel protein with two copies of a CCCH finger motif previously described in the germline proteins PIE-1 and MEX-1 in C. elegans, and in the mammalian TIS11/Nup475/TTP protein. However, mutations in pos-1 cause several defects in the development of the germline blastomeres that are distinct from those caused by mutations in pie-1 or mex-1. The earliest defect detected in pos-1 mutants is the failure to express APX-1 protein from maternally provided apx-1 mRNA, suggesting that POS-1 may have an important role in regulating the expression of maternal mRNAs in germline blastomeres.

Amino Acid Sequence↗
PubMed1999

Antiangiogenic therapy of human esophageal cancers with thalidomide in nude mice.

BACKGROUND: Thalidomide (alpha-N-phthalimidoglutarimide) is attracting new attention because of its antiangiogenic effect in corneal neovascularization models. However, the effect of this agent on esophageal carcinoma is yet to be established. METHODS: The human esophageal squamous cell carcinoma strains ES63 and ES80 implanted subcutaneously in nude mice were used to evaluate the antiangiogenic effect of thalidomide (200 mg/kg/d) after daily gavage or intraperitoneal administration. Tumor size was measured, and assessment of microvessel density was performed histochemically with Griffonia simplicifolia lectin I. Characterizations of angiogenic growth factors, vascular endothelial growth factor, basic fibroblast growth factor, and thymidine phosphorylase in ES63 and ES80 tumors were done by immunohistochemical staining and reverse transcription-polymerase chain reaction. RESULTS: ES63 strongly expressed 3 angiogenic factors, but ES80 showed moderate expression of thymidine phosphorylase and only weak or no expression of vascular endothelial grown factor and basic fibroblast growth factor at protein and messenger RNA levels. In ES63 intraperitoneal injection of thalidomide produced significant (P < .05) inhibition of tumor growth, but there was no effect after gastric gavage. Also, a significantly (P < .0005) lower microvessel density was encountered in the intraperitoneal thalidomide group. However, in the ES80 tumor strain thalidomide had no antiangiogenic effect after either intraperitoneal or oral administration. CONCLUSIONS: These data indicate that thalidomide exerts an antiangiogenic effect on solid tumor after intraperitoneal administration. Thalidomide might be one of the hopeful antiangiogenic drugs for solid tumors.

Animals↗
PubMed1998

Prognostic factors and rational approach in the treatment of submucosal cancer of the stomach.

In early gastric cancer, lymph node metastasis is known to be a prognostic factor. A retrospective study of 134 patients with submucosal gastric cancer (SMGC) who had undergone gastrectomy with lymph node dissection was performed to evaluate the prognostic factors and indication of postoperative chemotherapy. Five-year disease-free survival rate for 121 patients without nodal metastasis was 100% with (n = 62) or without postoperative chemotherapy (n = 59). On the other hand, it was 72.9% for 13 patients with nodal metastases, although all patients had undergone D2 or D3 resection and received postoperative chemotherapy. Tumor recurrence occurred only in three patients (n = 3) with alpha-fetoprotein (AFP) producing cancer and lymph node metastasis. Multivariate analysis with the Cox's proportional hazard model revealed AFP positivity to be a new independent prognostic factor in addition to lymph node metastasis in the patients with SMGC. Our findings suggest that routine use of postoperative chemotherapy does not appear rational for the patients without nodal metastasis and that new modalities of operation and chemotherapy may be necessary for the patients with AFP producing SMGC with nodal metastasis. The necessity of chemotherapy in conventional-type SMGCs with nodal involvement remains to be studied in future.

Adenocarcinoma↗
PubMed1998

Tumor vascularity predicts recurrence in differentiated thyroid carcinoma.

BACKGROUND: New prognosticators are necessary for optimizing the extent of thyroidectomy and adjuvant radiotherapy in differentiated thyroid carcinoma. METHODS: Tumor microvessel density (MVD), expression of thymidine phosphorylase (dThdPase) and CD68 stained macrophages were evaluated in 71 differentiated thyroid carcinomas by an immunohistochemical method. RESULTS: The recurrence-free survival was significantly (P <0.05) shorter in patients with hypervascular tumors but was not related to the dThdPase expression. Significant (R = 0.323, P <0.001) correlation between dThdPase expression score and increment in MVD was documented. Frequent high MVD and dThdPase expression were encountered in tumors >3 cm. Twenty-two of the 27 (82%) patients expressing high dThdPase were also evaluated positive for CD68 (P <0.001). CONCLUSIONS: Tumor MVD might be a new prognostic indicator of differentiated thyroid carcinoma, whereas dThdpase expression with high MVD might serve to identify a subgroup of thyroid carcinoma patients as potential candidates for adjuvant radiotherapy.

Adult↗
PubMed1998

Thymidine phosphorylase (platelet-derived endothelial cell growth factor), microvessel density and clinical outcome in hepatocellular carcinoma.

BACKGROUND/AIMS: Angiogenesis plays an important role in tumor growth and metastasis. It is regulated by angiogenic factors. Thymidine phosphorylase (platelet-derived endothelial cell growth factor) is one such factor. Although the significance of platelet-derived endothelial cell growth factor has been studied for several types of tumor, the expression of platelet-derived endothelial cell growth factor and its correlation with microvessel density or clinicopathological factors in hepatocellular carcinoma are unknown. We evaluated microvessel density and platelet-derived endothelial cell growth factor expression in hepatocellular carcinoma to determine whether microvessel density and platelet-derived endothelial cell growth factor expression are correlated with the clinicopathological factors of hepatocellular carcinoma. METHODS: Using immunohistochemical staining with anti-platelet-derived endothelial cell growth factor antibody and the ELISA method, we evaluated the correlation among platelet-derived endothelial cell growth factor expression, microvessel density and clinicopathological factors in 84 hepatocellular carcinoma patients. Microvessels were stained with anti-human von Willebrand factor (anti-Factor VIII) and anti-CD34. RESULTS: In the surrounding liver, there was a significant correlation between microvessel density and platelet-derived endothelial cell growth factor expression (p=0.002), and hepatitis C virus-positive livers had higher microvessel densities than otherwise (p=0.003). However, this correlation was not found for hepatocellular carcinoma, but hepatitis C virus-positive tumors had higher expression of platelet-derived endothelial cell growth factor (p=0.018). Microvessel density in hepatocellular carcinoma obtained by Factor VIII staining inversely affected the recurrence-free survival rate (p=0.0416), but the microvessel density by CD34 staining was not a significant predictor. CONCLUSIONS: This study indicates that platelet-derived endothelial cell growth factor may not be a major regulator of angiogenesis of hepatocellular carcinoma, but this enzyme may play an important role in hepatocarcinogenesis cooperating with hepatitis C virus. Also, the density, not of sinusoid-like vessels, but of larger vessels in hepatocellular carcinoma could be a prognostic factor for hepatocellular carcinoma.

Antigens, CD↗