Biomedical subjects

N Onoda

Publications and source records attributed to N Onoda.

136 records · Page 8Linked to original sources

PubMedDate not supplied

Cyclin D1 overexpression and prognosis in colorectal adenocarcinoma.

Recently, it has been reported that cyclin D1 plays a major role in oncogenesis in various cancers; however, there have been few studies on the association of cyclin D1 overexpression and prognosis of patients with malignant tumors. We evaluated the prognostic significance of cyclin D1 overexpression in colorectal adenocarcinoma. One hundred twenty-three specimens resected from patients with colorectal adenocarcinomas were investigated by staining with a monoclonal antibody against cyclin D1. As a result, both overall survival and disease-free survival were significantly poorer in the patients with tumors strongly positive for cyclin D1 than in those with cyclin-D1-negative or weakly positive tumors. The 5-year survival rate of the patients with tumors strongly positive for cyclin D1 was 53.3%, while the 5-year survival rates of patients with cyclin-D1-negative and weakly positive tumors were 96.2 and 78.8%, respectively. Moreover, multivariate analysis indicated that cyclin D1 overexpression is an independent predictor of disease recurrence in our patients. In conclusion, cyclin D1 overexpression may be useful as a predictor of disease recurrence in colorectal adenocarcinoma.

Adenocarcinoma↗

PubMedDate not supplied

Predictive value of Bcl-2 and Bax protein expression for chemotherapeutic effect in gastric cancer. A pilot study.

We investigated tissue staining for Bcl-2 and Bax proteins, which regulate apoptosis, as indicators of chemotherapeutic effect in patients with gastric cancer. In 23 patients with gastric carcinoma biopsy specimens were obtained endoscopically prior to chemotherapy and stained immunohistochemically with anti-Bcl-2 and anti-Bax antibodies. Patients then were treated with continuous infusion of 5-FU and cisplatin. No correlation was seen between chemotherapeutic effect and Bcl-2 or Bax alone. However, among the Bax-positive cases, the patients with Bcl-2-positive tumors were significantly more chemoresistant (p = 0.036) and had worse prognoses (p = 0.008) than Bcl-2-negative cases. Therefore, immunohistochemical staining for Bcl-2 protein may predict chemotherapeutic efficacy or guide specific therapeutic choices in treating Bax-positive tumors.

Aged↗

PubMedDate not supplied

Expression of p53 and vascular endothelial growth factor associated with tumor angiogenesis and prognosis in gastric cancer.

Recently, it has been reported that p53 tumor suppressor gene plays an important role in controlling tumor angiogenesis by regulating expression of vascular endothelial growth factor (VEGF), which is a well-characterized angiogenic inducer. In this study, we investigated these antigens' expression together with microvessel density, and investigated their clinical importance. One hundred twenty specimens resected from patients with gastric carcinoma were investigated using immunohistochemical methods. p53 and VEGF expression was observed in 42 and 35% tumors, respectively. p53 and VEGF staining status was coincided in 72% tumors, and a significant correlation was found between p53 and VEGF status. The microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in p53-positive or VEGF-positive tumors. According to prognosis, patients with p53-positive tumors had significantly worse survival than those with p53-negative tumors. There was also a significant worse survival in the patients with VEGF-positive tumors than those with VEGF-negative tumors. Moreover, the 5-year survival rate was lowest in the patients with p53-positive and VEGF-positive tumors, while it was highest in the patients with p53-negative and VEGF-negative tumors. In conclusion, both p53 and VEGF significantly correlated with tumor vascularity and prognosis in patients with gastric carcinoma.

Adult↗

PubMedDate not supplied

Association of tumor cell proliferation with lymph node metastasis in early gastric cancer.

Recently, many studies have reported on the relationship between malignant potential of neoplasms and cell proliferation. Proliferating cell nuclear antigen (PCNA) is an auxiliary protein of DNA polymerase delta and is considered to correlate with the cell's proliferative state. In this study, we investigated the correlation between tumor cell proliferation and nodal status of early gastric carcinoma. One hundred two endoscopically biopsied specimens from patients with early gastric carcinoma prior to operation were investigated by an immunohistochemical study, using anti-PCNA monoclonal antibody. Correlation of PCNA labeling index (percentage of positive cells per over 500 tumor cells) with nodal status were studied. PCNA labeling index in patients with lymph node metastasis was significantly higher in those without metastasis. Moreover, multivariate analysis indicated that PCNA labeling index is an independent significant factor for lymph node metastasis. As a result of this study, PCNA labeling index was suggested to be effective as one of the predictors of lymph node metastasis.

Adult↗

PubMedDate not supplied

Elevation in putrescine level and spermidine/spermine N1-acetyltransferase activity coincide with tumor development in 1, 2-dimethylhydrazine-induced rat colon.

Spermidine/spermine N1-acetyltransferase (SSAT), rate-limiting enzyme of polyamine interconversion, has been demonstrated to play an important role in malignant transformation of cells. We examined the involvement of altered polyamine metabolism in the colonic carcinogenesis, using 1,2-dimethylhydrazine (DMH)-induced rat colon tumor model. Following findings were obtained: i) Ornithine decarboxylase demonstrated high activity from the early phase in colon mucosa, and increased significantly in tumors. ii) Spermidine and spermine levels gradually elevated in DMH-treated mucosa, while putrescine increased significantly in tumor tissues. iii) SSAT activity increased gradually in DMH-treated colon mucosa, which preceded elevation of tissue putrescine level, and coincided with tumor development. In conclusion, elevation of putrescine level and induction of SSAT activity are suggested to have a close association in colonic carcinogenesis.

1,2-Dimethylhydrazine↗

PubMedDate not supplied

Telomerase activity in thyroid tumors.

We quantified telomerase activities in thyroid tumors by a telomeric-repeat-amplification-protocol-based assay in an attempt to determine its clinical significance. Telomerase activity was detected in 10 of 18 (55.6%) malignant tumors, but in none of the four benign lesions, and the level of telomerase activity correlated significantly with the progression of the clinical stages. High activity was determined in 4 (80%) of 5 metastatic lesions in the lymph nodes. Five (45.5%) of 11 non-tumoral specimens from malignant cases showed telomerase activity, while none of the four from benign cases did. In conclusion, the determination of telomerase activity might be useful in determining the existence and progression of thyroid cancer.

Adult↗

PubMedDate not supplied

Evaluation of argyrophilic nucleolar organizer regions (AgNORs) in differentiated thyroid carcinoma as an indicator for disease recurrence.

Differentiated thyroid carcinoma (DTC) is one of the least aggressive cancers of the human malignancies, however, recurrent disease is occasionally found and is difficult to determine the risk for recurrence only by clinicopathological features. In the present study, we investigated argyrophilic nucleolar organizer regions (AgNORs) score, a well-known indicator for proliferative potential of the cancer cells, in 89 cases of DTC. In tumors with capsular invasion, or with extended contra-lateral lymph node metastasis, AgNORs score was significantly higher than in tumors without them, while was not correlated with age or gender of the patients, nor the histological type of the tumor (papillary or follicular). Disease recurrence was observed in one-third of the patients in high AgNOR score group (scored more than mean value +/- standard deviation) when the patients were divided into four groups according to the AgNOR score, and a significantly higher risk for disease recurrence was demonstrated in those cases with high AgNOR score than cases with lower score. These results clearly indicated the usefulness of AgNOR score in selecting the patients at high risk for disease recurrence. All 5 recurrent cases displayed local recurrence in high AgNOR score group, while 5 of 7 cases with low AgNOR score did in the manner of hematological metastasis. In conclusion, this method was technically simple and accurate giving an exact value in individual cases. Thus, we believe AgNOR score might be clinically applicable as a useful indicator for disease recurrence in DTC.

Adenocarcinoma, Follicular↗

PubMedDate not supplied

Expression of thrombospondin-1 inversely correlated with tumor vascularity and hematogenous metastasis in colon cancer.

Solid tumors require neovascularization for growth and metastasis. Angiogenesis depends on the local balance between various molecules that induce and inhibit neovascularization. Thrombospondin-1 (TSP-1) is thought to be an antiangiogenic factor. In this study, we examined the correlation between expression of TSP-1 and tumor vascularity, and determined its prognostic significance in colon cancer. Microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in tumors that were TSP-1-negative. TSP-1 expression was inversely correlated with prognosis. Patients with TSP-1-negative tumors had a significantly worse prognosis than did those with TSP-1-positive tumors. Frequency of hepatic recurrence was significantly higher in patients with tumors that were TSP-1-negative. In conclusion, TSP-1 is an important negative-regulator of tumor angiogenesis, and TSP-1 may be useful for predicting recurrence in patients with colon cancer.

Adenocarcinoma↗

PubMedDate not supplied

Bcl-2 expression in breast cancer is down-regulated by trans-arterial administration of chemotherapeutic agents.

Bcl-2 is one of the cytoplasmic oncoproteins, and has been shown to suppress apoptotic cell death. In this study, we investigated the relationship between Bcl-2 expression and effects of chemotherapeutic agents on human breast cancer cells. We examined 26 surgically resected breast tumors with preoperative trans-arterial administration of chemotherapeutic agents and 30 control cases using immunohistochemical methods. In all 26 cases in the chemotherapy group, the breast cancer cells were focally degenerated to various degrees, associated with inflammation and stromal desmoplastic changes. Bcl-2 expression was found in 46% (12/26) of the chemotherapy group and in 67% (20/30) of controls. Of the 12 Bcl-2-positive cases in the chemotherapy group, 5 were diffusely positive [Bcl-2(2+)] and 7 were focally positive [Bcl-2(+)]. Of the 20 Bcl-2-positive cases in the control group, 18 were diffusely positive and 2 were focally positive. We speculate that Bcl-2 expression was down-regulated by trans-arterial administration of chemotherapeutic agents and was associated with apoptosis and degeneration of breast cancer cells.

Adult↗

PubMedDate not supplied

Early stage carcinoma of the gastric remnant in Japan.

In recent years, the number of reported cases of early stage cancer of the remnant stomach has been on a gradual increase thanks to the improvement in diagnostic techniques and also to increasing dealings with cancer of the remnant stomach. In this study we reviewed 124 cases of early stage cancer of the remnant stomach which were reported in Japan by the end of 1990, including the 6 cases which we encountered ourselves, during the 11 years starting from 1980. Their average age was 57 years, with a range from 22 to 78 years. The male-to-female ratio was 2:7. There were 63 asymptomatic cases (61%). This fact suggests that periodical examinations are essential after the first operation on the stomach. Out of the 124 cases, 86 cases operated on for benign lesions (benign group) and the remaining 38 cases for malignant lesions (malignant group) for the first time. The average time between the first and the second surgery was 19.7 years in the benign group and 7.8 years in the malignant group. The initial surgery was performed mainly by Billroth II resection. The frequency of tumor development was higher in the nonsutured portion than in the anastomosed portion of the remnant stomach. Protuberant type lesions and differentiated carcinomas were prevalent according to the classification by gross type and histology, respectively. However, the anastomosed portion was most often involved in the subgroup of patients in whom lesions were detected more than 10 years after Billroth II resection for benign lesions.

Adult↗