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M Toi

Publications and source records attributed to M Toi.

At least 127 records · Page 7Linked to original sources

Quantitative analysis of vascular endothelial growth factor in primary breast cancer.

BACKGROUND: Recent clinical studies have demonstrated that tumor angiogenesis is a potent prognostic indicator for breast cancer patients. The quantitation of endothelial growth factors is thought to be useful to assess angiogenic phenotype in the tumor. Among the many new endothelial growth factors, vascular endothelial growth factor (VEGF) is known to be particularly responsible for promoting the neovascularization in human breast cancer. METHODS: Intratumoral protein levels of VEGF were measured by enzymatic immunoassay in 135 primary breast cancer tissues. The VEGF levels were compared with the microvessel density evaluated by immunostaining the endothelial antigen and also were compared with intratumoral protein levels of other endothelial growth factors, including basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF). RESULTS: Intratumoral VEGF concentrations varied from 3.3 pg/mg protein to 2032 pg/mg protein (average 148 pg/mg protein). An immunocytochemical analysis using anti-VEGF antibody confirmed that VEGF was located mainly in the cytoplasm of the tumor cells. The VEGF concentrations were significantly higher in vascularly rich tumors than in vascularly poor tumors. No significant association was found between VEGF concentrations and the two other endothelial growth factor concentrations. CONCLUSIONS: The quantitation of intratumoral VFGF levels seems to be useful for assessing the activity of tumor angiogenesis.

Breast Neoplasms↗

Protective effect of leuprolide acetate on 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis in rats.

The anti-carcinogenic effect of TAP-144-SR biodegradable microcapsules of copoly (DL-lactic/glycolic acid) copolymer containing a potent LHRH agonist, TAP-144 (D-Leu6-(des-Gly10-NH2)-LHRH ethylamide, leuprolide acetate) was investigated in 7,12-dimethylbenz(a)anthracene (DMBA)-induced rat mammary tumours. At 50 days of age, all rats were given 20 mg doses of DMBA by gastric intubation. Rats on the Initiation Group were given a single s.c. injection of TAP-144-SR (3 mg/kg) 1 week before DMBA treatment, and rats in the Promotion Group were given repeated s.c. injections every fourth week from 1 week after DMBA treatment until the end of the experiment. In the Initiation Group, tumour incidence and multiplicity were reduced to 20.8% and 15.0% of the Control Group values, respectively. In the Promotion Group, tumour incidence and multiplicity were also reduced to 17.7% and 7.9%, respectively. It was suggested that TAP-144-SR may be a potential candidate as an agent for hormonal chemoprevention in breast cancer.

9,10-Dimethyl-1,2-benzanthracene↗

[Breast cancer angiogenesis].

Recent clinical investigations have confirmed that angiogenesis is a basic property of solid tumors as well as proliferation, invasion and metastasis. In addition to the fundamental analysis of tumor angiogenesis in clinical tumors, the focus has been on clinical applications of tumor angiogenesis. Representatives are applications for prognostic indicators of primary breast tumor and for antiangiogenesis therapy. The clinical value of angiogenesis-related factors as a tumor marker and diagnostic applications targeting newly-developed vasculatures have been investigated. In this review, recent new findings on the clinical applications of tumor angiogenesis in human tumors, particularly breast cancer, will be summarized and discussed.

Biomarkers, Tumor↗

Regulation of endothelial growth factor expressions in breast cancer.

Expression of various endothelial growth factors including vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), Platelet-derived endothelial cell growth factor (PD-ECGF) and hepatocyte growth factor (HGF) was investigated in human breast carcinoma tissues, and the results were compared to the intratumoral microvessel density evaluated by the immunostaining to anti-factor VIII related antigen. VEGF and PD-ECGF were examined by immunostainings, and bFGF and HGF were assessed by enzymatic immunoassays. As a result, VEGF and PD-ECGF were significantly associated with the increment of microvessel density, although no significant correlation was found with bFGF and HGF. In addition, interestingly, a tendency of co-expression between VEGF and PD-ECGF was demonstrated. It was suggested that VEGF and PD-ECGF play important roles in the promotion of angiogenesis in human breast cancer.

Breast Neoplasms↗

[The importance of tumor angiogenesis as a prognostic indicator in primary breast cancer].

Recently, the importance of tumor angiogenesis in the process of tumor growth, progression and metastasis in solid tumors has been widely accepted. The prognostic value of angiogenesis has been demonstrated in a variety of solid tumors including breast cancer. In this report, we reviewed recent studies investigating on the value of intratumoral microvessel density (MVD), assessed by a sermiquantitative immunohistochemical assay with using factor-VIII related antibody or anti CD-31 antibody, as a prognostic indicator in primary breast cancer patients. Studies using factor-VIII related antibody showed that the average MVD ranged from 67.3 to 84.0 counts per mm2 area. When used by anti CD-31 monoclonal antibody, the average MVD were 120.3 approximately 135 counts per mm2 area in the range. More than 8 clinical investigations have showed that MVD was a potent prognostic indicator for relapse free survival and/or overall survival in both node-negative and -positive patients. Two reports concluded no prognostic value of MVD, however the average MVD of these two studies significantly differed from other reports. Thus, at present, angiogenesis grade seems to provide an independent prognostic value when the MVD was properly assessed. With respect to the relationship with conventional prognostic indicators, several reports showed the tendency that increased MVD was correlated with younger age and increase of tumor size below 3 cm diameter, however, some reports failed to demonstrate the tendency, suggesting that these correlations are still in controversial. Biological markers including ER, p53 and c-erB2 showed no correlation with the MVD in many studies including our investigation. Only a significant correlation we found was that MVD was increased in tumors with the expression of vascular endothelial growth factor and platelet-derived endothelial cell growth factor, which are noted to be potent endothelial growth factor. Since the evaluation of tumor angiogenesis as a prognostic indicator is now widely investigated in a prospective study, MVD might be introduced to the category of the criteria for determining the schedule of postoperative adjuvant therapy of breast cancer.

Age Factors↗

Growth inhibition of K-ras-expressing tumours by a new vinca alkaloid, conophylline, in nude mice.

Conophylline, a new vinca alkaloid isolated from the plant Ervatamia microphylla induced normal flat morphology in K-ras-NRK and K-ras-NIH cell lines, and lowered the increased uptake of 2-deoxyglucose in K-ras-NRK cells. Conophylline inhibited the growth of K-ras-NRK cells, but this inhibition was reversible. The alkaloid also inhibited the growth of K-ras-NRK and K-ras-NIH3T3 tumours transplanted into nude mice. On the other hand, it showed no effect on survival of the mice loaded with L1210 leukaemia. Thus, conophylline is a new antitumour vinca alkaloid that induced normal phenotypes in ras-expressing cells.

Animals↗

Concentrations of vascular endothelial growth factor in the sera of normal controls and cancer patients.

Vascular endothelial growth factor (VEGF) is known to play crucial roles in tumor angiogenesis. We have investigated the circulating level of VEGF in sera from cancer patients as well as from healthy normal controls using a sensitive enzymatic immunoassay. Immunoreactive VEGF proteins were detectable in normal sera, and the cutoff level was determined to be 180 pg/ml. In examined patients with all types of cancer, including breast, gastrointestinal, hepatobiliary, and lung cancer, an aberrant increase in the circulating level of VEGF was detected. For example, in 137 primary breast cancer patients, 12 (8.8%) showed an aberrant increase in VEGF levels. This aberrant expression of VEGF in sera was significantly associated with the progression of the disease, and with VEGF protein expression in tumor tissues. In addition, a Western blot analysis confirmed the presence of the VEGF165 form in sera from a patient with recurrent breast cancer. It was concluded that VEGF was detectable in normal sera, and its level was increased in some populations of cancer patients. A positive angiogenesis regulator, VEGF might function as an endocrine growth factor, particularly for solid tumors.

Adult↗

Expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase in human breast cancer.

We have investigated the expression of platelet-derived endothelial-cell growth factor/thymidine phosphorylase (PD-ECGF/dThdPase) in human breast-cancer tissues by the immunocytochemical method using anti-PD-ECGF/dThdPase monoclonal antibody. Out of 100 invasive-ductal-carcinoma tissue samples, 39 (39%) were evaluated as PD-ECGF/dThdPase-positive. The expression of PD-ECGF/dThdPase was identified mainly in the cytoplasma of tumor cells. The expression of PD-ECGF/dThdPase was significantly associated with the microvessel density assessed by immunostaining to factor-VIII-related-antigen (p < 0.05). However, there was no correlation between expression of PD-ECGF/dThdPase and menopausal status, tumor size, axillary lymph-node metastases, hormone-receptor status, epidermal-growth-factor receptor, or erb-B-2-protein and p53-protein expression. We suggest that expression of PD-ECGF/dThdPase plays an important role in the promotion of angiogenesis in human breast cancer.

Antibodies, Monoclonal↗

Tumor angiogenesis in breast cancer: its importance as a prognostic indicator and the association with vascular endothelial growth factor expression.

The importance of tumor angiogenesis in the process of tumor growth and progression in solid tumors has been widely accepted. We have investigated the significance of tumor angiogenesis as a prognostic indicator in a retrospective study including 328 primary breast cancer patients. The postoperative survey demonstrated that the microvessel density (MVD) evaluated by immunocytochemical staining for factor VIII-related antigen is a potent prognostic indicator. The relapse-free survival (RFS) rate of patients with over 100 microvessels/mm2 in a microscopic field was significantly worse compared to that of patients with less than 100 microvessels/mm2 (p < 0.00001). The significance of MVD was found in both node-negative and node-positive patients (p < 0.005 and p < 0.01, respectively). Multivariate analysis confirmed that MVD is an independent prognostic indicator for RFS. In the background factor analysis, MVD was significantly correlated with the number of metastatic nodes (p < 0.01). In addition, the immunocytochemical analysis for vascular endothelial growth factor (VEGF) demonstrated a close association between the increase in MVD and the expression of VEGF (p < 0.001). VEGF status also was a significant prognostic indicator in univariate analysis for RFS (p < 0.01). It was concluded that MVD is a potent prognostic indicator in primary breast cancer. Furthermore, it was also suggested that VEGF plays crucial roles in the promotion of angiogenesis in breast cancer.

Breast Neoplasms↗

[Significance of tumor angiogenesis as an independent prognostic factor in axillary node-negative breast cancer].

The value of tumor angiogenesis, EGFR and c-erbB-2 oncoprotein, a long with p 53 protein expression for predicting relapse-free survival was investigated in 110 node-negative breast cancer patients. The grade of neovascularization was assessed by the microvessel density which was obtained by an immunocytochemical staining by factor VIII-related antigen. EGFR, c-erbB-2 oncoprotein and p 53 oncoprotein were also determined by immunocytochemical assay. Univariate analysis showed no statistical significance of EGFR, c-erbB-2 and p53 status as a prognostic indicator. However, the microvessel density was a significant predictor of relapse-free survival. Patients with over 100 counts of factor VIII-RA positive cells per mm2 field in the most active areas of neovascularization showed significantly poorer prognosis compared to those with less than 100 counts (p < 0.005). Multivariate analysis demonstrated that microvessel density was an independent prognostic indicator in node-negative breast cancer patients (p < 0.0005). It was suggested that microvessel density might be of use in selecting the high-risk group in node-negative breast cancer patients needing adjuvant therapies.

Adenocarcinoma↗

Sweat gland carcinoma in a human immunodeficiency virus-infected patient.

Eccrine (sweat gland) carcinoma is a rare form of skin cancer that may be locally destructive. It is known to recur after resection and can metastasize to regional or distant lymph nodes. There have been two reported cases in association with patients immunocompromised as the result of organ transplantation (I. Penn: Prog Allergy. 37: 259, 1986). We report here the first case of sweat gland carcinoma in a patient infected with the human immunodeficiency virus.

Acquired Immunodeficiency Syndrome↗

[The effect of combination treatment consisted of 5'-deoxy-5-fluorouridine and medroxyprogesterone acetate for recurrent breast cancer patient].

The effect of the combination treatment consisted of 5'-deoxy-5-fluorouridine (5'-DFUR) and medroxyprogesterone acetate (MPA) was investigated in 20 recurrent breast cancer patients. Out of 20 patients, 8(40.0%) responded to the treatment. The average duration of response was 10.3 months. Response rates stratified by recurrence site were soft tissues 36.4%, bone 44.4%, liver 60.0% and lung 20.0%, respectively. No serious side effect except body weight gain, which was caused by MPA, was seen. In a 76-year-old woman with liver metastases, a marked response was obtained and has continued for more than 24 months. It was suggested that the combination of 5'-DFUR and MPA may be effective for recurrent breast cancer patients.

Administration, Oral↗

Vascular endothelial growth factor and platelet-derived endothelial cell growth factor are frequently coexpressed in highly vascularized human breast cancer.

Vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) are known to be angiogenic growth factors in vitro and in vivo. In this study, we have investigated the relationship between VEGF expression and PD-ECGF expression in human breast cancer tissues using immunocytochemical methods. Of 152 primary breast cancers, 84 (55.3%) and 71 (46.7%) were positive for VEGF and PD-ECGF, respectively. Fifty-three (63. 1%) of 84 VEGF-positive tumors had a PD-ECGF-positive phenotype, whereas only 18 (26.5%) of 68 VEGF-negative tumors had a PD-ECGF-positive phenotype. There was a significant correlation between the VEGF expression and PD-ECGF expression (P < 0.01). As a single factor, VEGF expression and PD-ECGF expression were significantly associated with an increase in the microvessel density assessed by the immunocytochemical analysis using antifactor VIII-related antigen mAb. Interestingly, in addition, of 53 tumors with more than 100 microvessel counts/1 mm2, 40 (75.5%) had both VEGF- and PD-ECGF-positive phenotypes. It was found that VEGF and PD-ECGF were frequently coexpressed in highly vascularized tumors with high microvessel counts. It is suggested that VEGF and PD-ECGF might cooperatively function in the neovascularization of human breast cancer.

Breast Neoplasms↗

Serum concentrations of hepatocyte growth factor in breast cancer patients.

Hepatocyte growth factor (HGF) was first identified as a potent stimulator of hepatocyte growth and DNA synthesis. Later, it was shown that HGF can promote cell motility and cell proliferation in various types of cells, including tumor cells and endothelial cells. We have examined serum concentrations of HGF in breast cancer patients using an ELISA. Of 134 primary breast cancer patients, 49 (36.6%) showed a significant increase in the circulating level of HGF as compared to healthy controls. The increase in the HGF level was significantly associated with axillary lymph node metastases and histological evidence of venous invasion. No significant correlation between serum HGF concentrations and intratumoral HGF concentrations was found; however, the removal of the primary tumor clearly decreased the serum HGF level, suggesting that the elevation of HGF in the serum was tumor related. Twenty-nine (82.9%) of 35 patients with recurrent breast cancer had an increase in the serum HGF level. The HGF level was significantly higher in patients with liver metastases compared to those with other sites of metastases. Postoperative sequential examinations confirmed that the increase in the serum HGF level was associated with the appearance of relapse. In conclusion, the serum HGF level was significantly increased in breast cancer patients. Circulating HGF might play important roles in tumor progression in this malignancy.

Adult↗

Role of epidermal growth factor receptor expression in primary breast cancer: results of a biochemical study and an immunocytochemical study.

We have conducted two series of studies, a biochemical study and an immunocytochemical study, to investigate the role of epidermal growth factor receptor (EGFR) expression in primary breast cancer patients. In the biochemical study, a consecutive 115 patients were included and EGFR was measured by a competitive binding assay with multipoint Scatchard analysis. In the immunocytochemical study comprising 126 patients, EGFR status was determined by immunostaining with anti-EGFR antibody EGFR1. Several agreements were found from these two studies. EGFR status was inversely correlated with estrogen receptor (ER) status. No significant correlation was found between EGFR status and tumor size, nodal metastases, or the expression of c-erbB-2 protein. Ki-67 immunoreactivity, a cellular proliferation marker, was enhanced in EGFR positive tumors over EGFR negative tumors, suggesting a linkage of EGFR expression to cellular proliferative activity. Post-operative follow up showed that relapse-free survival for EGFR positive patients was significantly worse than that for EGFR negative patients, particularly in node-positive patients. Multivariate analysis demonstrated a significance of EGFR status as an independent prognostic indicator in primary breast cancer. The group expressing EGFR and c-erbB-2 protein indicated a particularly high risk for relapse.

Biomarkers, Tumor↗