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T Toge

Publications and source records attributed to T Toge.

At least 91 records · Page 5Linked to original sources
PubMed1995

DT-diaphorase as a target enzyme for biochemical modulation of mitomycin C.

We studied a selective enhancement of the mitomycin C (MMC)-induced antitumor effect focusing on the intracellular metabolism by NAD(P)H:quinone oxidoreductase (DT-diaphorase, DTD). The level of cellular DTD activity related well to the degree of MMC-induced DNA total cross links and cell growth inhibition in human cancer cell lines, KB, PH101, SH101 and K562. A DTD inhibitor, dicoumarol (DIC) or flavin adenine dinucleotide (FAD), inhibited the MMC-induced DNA damage and cytotoxicity at a non-toxic concentration. The DTD-mediated MMC activation was pH-dependent, and highest at pH 6 and lowest at pH 8. Although an inverse relationship appeared to exist between DTD activity and MMC efficacy in human xenografts implanted into nude mice and 9 fresh human tumor specimens, the investigation in 3 culture cells, HEC-46, HCC-48 and HCC-50, established from those xenografts, showed that DTD activated MMC in a pH-dependent manner as well as the other cell lines. Significant tumor pH reduction from 7.1 to 6.7 by continuous glucose infusion also increased the MMC-induced tumor growth inhibition in the human tumor xenografts. Thus, we conclude that bioreductive activation by DTD in a pH-dependent manner may be of key importance in the MMC-induced antitumor effect and that an increased MMC efficacy at a reduced pH caused by hyperglycemia may be applied to clinical use as a new manipulation for a biochemical modulation of MMC.

Animals↗
PubMed1994

Modulation of suppressor cell activities by cyclophosphamide in breast cancer patients.

We investigated the immunomodulatory effect of cyclophosphamide on the induction of suppressor cell activities in peripheral blood lymphocytes. The sera from advanced breast cancer patients as well as concanavalin-A (Con-A) induced suppressor cell activities in lymphocytes from healthy volunteers. Pretreatment of these lymphocytes, including CD4+ T cells with 4-hydroperoxycyclophosphamide (4-HC), an active form of cyclophosphamide, abrogated the induction of suppressor cell activities by either cancer sera or Con-A. A decrease in CD4+CD45RA+ suppressor/inducer T cells and reduction of Con-A induced suppressor cell activities were observed in breast cancer patients with metastases that were treated with cyclophosphamide (CPM). These results suggest that cyclophosphamide may modulate the immune responses of breast cancer patients by interference with suppressor/inducer T cells.

Breast Neoplasms↗
PubMed1994

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↗
PubMed1994

The inhibitory effect caused by suramin on the paracrine growth of human cancer cells and fibroblasts.

The growth interactions between human cancer cells and primary cultured human fibroblasts, and the effects of suramin on them, were investigated using a double-chamber technique combined with a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) assay. Human fibroblasts obtained from various organs resected surgically were cultured in a monolayer and used after the third or fourth passage. In the double-chamber assay, the growth of cancer cells in the top chamber was significantly stimulated by some types of fibroblasts in the bottom chamber in a fibroblast density-dependent manner. Interestingly, the growth of cancer cells was stimulated at 140%-147% by fibroblasts obtained from an organ where cancer cells had developed, the MCF-7 versus mammary fibroblasts, and in LS-180 versus colonic fibroblasts, but not by their fibroblast-conditioned medium. Suramin completely inhibited the growth-enhancing interaction between MCF-7 and mammary fibroblasts, and between SH-101 and lung fibroblasts at a clinical concentration of from 50 micrograms/ml to 300 micrograms/ml. It also reduced the growth of LS-180 co-cultured with colon-fibroblasts, but the inhibitory effect was incomplete. These results suggest that mutual growth reliance exists between human cancer cells and primary cultured fibroblasts by diffusible factors secreted by both cells, and that these enhancing effects are related in part to the growth and metastasis of cancer cells in vivo. Suramin was found to have an inhibitory effect on their interaction at a clinically achievable concentration in vitro.

Cell Division↗
PubMed1994

[Comparison of duodenogastric reflux (DGR) to esophageal substitute between retro-sternal route and posterior mediastinal route].

To elucidate superiority of route among surgery of esophageal cancer with stomach tube, duodenogastric reflux (DGR) were examined in nine cases of retro-sternal bypass (RS) and 18 cases of posterior mediastinal group (PM) by means of questionnaire of reflux esophagitis, esophageal transit scintigram and 24 hour pH monitoring to those patients. Firstly, in order to readily compare the two groups, each section of reflux symptoms was expressed as a brief score by dividing each symptom into strength (0-3) and frequency (0-3). Mean score of reflux sensation was less in RS than in PM significantly (0.9 vs. 2.9, p < 0.01). The median value showed that patients in PM had much DGR symptoms than those in RS significantly (8.5 vs. 5.5, p < 0.01). In esophageal transit scintigram, TcO4- (85 MBq) was counted by gamma camera at the upper (ROI-1), center (ROI-2), and lower (ROI-3) sites of the sternum bone in the upright position. The descending time of RI peak from ROI-1 to ROI-3 in RS was shorter than PM (2.1 sec vs. 3.9 sec, N.S.). At ROI-2, clearance rate of RI in RS was similar to that in PM. At ROI-3, clearance rate of RI in RS was better than that in PM significantly (80.0% vs. 49.6%, p < 0.05). Scintigram revealed RI stasis in PM, which might be presumably concerned to DGR. Intragastric pH was measured continuously 5 and 15 cm below the esophagogastrostomy using 2-channeled antimony pH sensors.(ABSTRACT TRUNCATED AT 250 WORDS)

Duodenogastric Reflux↗
PubMed1994

[Skin reaction to OK-432 and its dosage for locoregional administration].

Establishment of optimal dosage of OK-432, a streptococcal preparation, was studied based on its skin test was studied. Locoregional immunotherapy using OK-432 was conducted for patients with malignant fluids. More OK-432 was administered to patients having a weaker skin reaction to OK-432 and less to those having a stronger one, corresponding to their redness diameter of skin reaction. There was a marked difference in OK-432-skin test among patients. Some patients with malignant fluids having small redness responded to the treatment after a large amount of OK-432, and others were well controlled by a smaller dosage of OK-432. It is suggested that OK-432-skin test may provide the optimal dosage for local treatment of malignant fluids.

Ascitic Fluid↗
PubMed1994

[Early phase II study of KW-2307 in advanced or recurrent breast cancer. KW-2307 Cooperative Study Group (Breast Cancer Section].

A multi-institutional early phase II study of KW-2307 (vinorelbine), a new vinca alkaloid derivative, in advanced or recurrent breast cancer was conducted in 15 nationwide hospitals. KW-2307 was intravenously administered once weekly at doses of 15 to 25 mg/m2. Sixty-five among the enrolled 69 patients were eligible. Response rates were 11.8% (2/17) with 15 mg/m2, 28.0% (7/25) with 20 mg/m2 and 17.4% (4/23) with 25 mg/m2, and the overall response rate was 20.0%. Once-weekly intravenous administration of 20 mg/m2 was estimated to be the optimal dose of KW-2307 from the results. The major side effect was leucopenia, which was the dose-limiting factor in this study. Other subjective or objective side effects included anorexia, nausea-vomiting, phlebitis, fever, general fatigue and stomatitis, but none of them was serious.

Adult↗
PubMed1993

Antiproliferative effects of isoflavones on human cancer cell lines established from the gastrointestinal tract.

Seven isoflavones, biochanin A, daidzein, genistein, genistin, prunectin, puerarin, and pseudobaptigenin were tested for cytostatic and cytotoxic effects on 10 newly established cancer cell lines of the human gastrointestinal origin. Proliferation of HSC-41E6, HSC-45M2, and SH101-P4 stomach cancer cell lines was strongly inhibited by biochanin A and genistein, whereas other stomach, esophageal, and colon cancer lines were moderately suppressed by both compounds. Biochanin A and genistein were cytostatic at low concentrations (< 20 micrograms/ml for biochanin A, < 10 micrograms/ml for genistein) and were cytotoxic at higher concentrations (> 40 micrograms/ml for biochanin A, > 20 micrograms/ml for genistein). DNA fragmentation was observed at cytotoxic doses of both compounds, indicating the apoptotic mode of cell death by the compounds. Chromatin condensation and nuclear fragmentation of each cell line were also observed. The advent of apoptosis was dose dependent for both isoflavones. Biochanin A suppressed tumor growth of HSC-45M2 and HSC-41E6 lines in athymic nude mice. Our results suggest that two of isoflavone derivatives, biochanin A and genistein, inhibit the cell growth of stomach cancer cell lines in vitro through activation of a signal transduction pathway for apoptosis. Moreover, in vivo experiments demonstrate that biochanin A can be used as an anticancer agent.

Animals↗
PubMed1993

Relevance of DT-diaphorase activity to mitomycin C (MMC) efficacy on human cancer cells: differences in in vitro and in vivo systems.

Using 4 human cancer cell lines, 4 tumors xenografted into nude mice, and 11 fresh tumor specimens removed at surgery, we investigated the relevance of NAD(P)H:quinone oxidoreductase (DT-diaphorase, DTD) activity (nmoles/min/mg protein) to mitomycin C (MMC)-induced cytotoxicity. In culture cell lines, KB cells had significantly higher levels of DTD activity (8260) than PH101 (1934), SH101 (1805) or K562 (1796), and the highest sensitivity to MMC. In contrast, the higher the DTD activity of xenografts, the greater their resistance to MMC, while the inhibition rate of relative tumor growth for MMC, as evaluated by the NCI protocol, was highest in SH-6, high in CH-5, lower in CH-4 and lowest in EH-6. The investigation using 11 fresh tumor specimens also showed an inverse relationship between IC50 values after a 30-min MMC treatment, as evaluated by ATP assay and DTD activities. Moreover, a non-toxic DTD inhibitor, dicoumarol (DIC), or flavin adenine dinucleotide (FAD), suppressed the efficacy of MMC in culture cells, but enhanced it in xenografts. Thus, we suggest that DTD may play an important role in MMC-induced cytotoxicity but MMC metabolism by DTD in solid tumors may differ from that in culture cells.

Animals↗
PubMed1993

Primary squamous cell carcinoma of the breast after cured Hodgkin's disease.

An unusual case of primary squamous cell carcinoma of the breast occurring after cured Hodgkin's disease is reported herein. A 27-year-old woman developed a left breast mass 2 years after chemotherapy and radiation for nodular sclerosing stage IIB Hodgkin's disease. Excisional biopsy revealed squamous cell carcinoma of the breast and a modified radical mastectomy was performed, however, no metastasis was found in the axillary nodes. She received etoposide, mitomycin-C, and doxifluoridine as adjuvant chemotherapy, and remains well without any evidence of recurrent Hodgkin's disease or breast cancer. To our knowledge, this is the first reported case of primary squamous cell carcinoma of the breast associated with Hodgkin's disease. The risk of patients treated for Hodgkin's disease developing breast cancer as a second malignant neoplasm is discussed following the report of this case.

Adult↗
PubMed1993

The role of lymphocyte surface binding sites for wheat germ agglutinin in the negative regulation of cancer patients.

The role of lymphocyte surface binding sites for wheat germ agglutinin (WGA) in the negative regulation of cancer patients was investigated. The number of WGA binding sites on the surface of each lymphocyte ranged from 10(7) to 10(8). Fluorescein isothiocyanate (FITC)-conjugated WGA, bound to the majority of peripheral blood lymphocytes (PBL) with two peaks of fluorescent intensity was expressed either dimly or brightly. The increase in lymphocytes brightly expressing WGA fluorescent intensity (WGA bright lymphocytes) significantly correlated with the number of WGA binding sites. The suppression of lymphocyte proliferation mediated by the purified soluble suppressor factor (SSF) significantly correlated with an increase in the WGA bright lymphocyte population (P < 0.05). A significantly greater number of WGA bright lymphocytes in PBL was found in patients with esophageal, gastric, breast, or colon cancer, than in those with benign diseases or in healthy controls. Furthermore, an increase in WGA bright lymphocytes was found in subsets expressing the antigens CD8 dimly or CD16. Thus, it is suggested that the number of WGA binding sites may increase mainly on the surface of effector cells such as NK cells and CD8-positive killer T cells in cancer patients, triggering the negative regulation mediated by SSF.

Adult↗
PubMed1993

Expression of growth factors and their receptors in human esophageal carcinomas: regulation of expression by epidermal growth factor and transforming growth factor alpha.

The expression of mRNAs for epidermal growth factor (EGF), transforming growth factor alpha(TGF alpha), EGFR, platelet-derived growth factor (PDGF) A and B chain, PDGF receptor (PDGFR), transforming growth factor beta (TGF beta), erbB-2 and estrogen receptor (ER) genes was first examined in 6 human esophageal carcinoma cell lines, 6 xenoplanted and 15 surgically resected esophageal carcinomas. Secondly, the effect of EGF and TGF alpha on the expression of these genes by the TE-1 esophageal carcinoma cell line was investigated. The expression of EGF mRNA was detected in 8 (29.6%) of 27 tumors including the cell lines, whereas the TGF alpha and EGFR genes were expressed in 21 (77.8%) and 24 (88.9%) tumors respectively. PDGF B chain and PDGFR were detected in 18 (66.7%) and 20 (74.1%), respectively, and ER mRNA was observed in 16 (59.3%) tumors. Genes for PDGF A chain and TGF beta and the erbB-2 gene were commonly expressed. On the other hand, exogenous EGF and TGF alpha stimulated the expressions of fos and myc genes by TE-1 cells. The expression of mRNAs for TGF alpha, PDGF A and B chain and the erbB-2 genes was also increased after treatment with EGF. TGF alpha increased the accumulation of mRNAs for EGF, TGF alpha, EGFR, PDGF A and B chain and the erbB-2 gene. Moreover, the expression of mRNAs for interstitial collagenase, stromelysin and type IV collagenase was increased after EGF or TGF alpha treatment. These results indicate that EGF and TGF alpha may regulate the multi-growth-factor receptor expression and may play a central role for tumor invasion and metastasis as autocrine modulators for human esophageal carcinoma.

Adenocarcinoma↗
PubMed1993

The expression and biological activity of IL-2 receptor on a human pancreas cancer cell line.

To ascertain whether the tumor cells can regulate the host immune systems through the production of the cytokines or their receptors, we examined the expressions of tumor necrosis factor alpha (TNF alpha), tumor necrosis factor beta (TNF beta), interleukin 2 (IL-2) and interleukin 2 receptor alpha chain (IL-2R alpha) on the human cancer cell lines by Northern blot analysis. We used K562 (leukemia cell line), MCF-7 (breast cancer cell line), LS180, HT29 (colon cancer cell lines), SH101 (gastric cancer cell line) and PH101 (pancreas cancer cell line). Expressions of TNF alpha, TNF beta and IL-2 mRNA were not detected in any of the tumor cell lines. However, 1.4 and 3.5 kilobases of the IL-2R alpha mRNA were expressed in the PH101 cells, but not in the other five cell lines. Furthermore, IL-2R alpha was detected on the cell surface of the PH101 cells by the flow-cytometric analysis with an anti-IL-2R alpha monoclonal antibody. Interestingly, the soluble IL-2R alpha (sIL-2R alpha) was found in the conditioned media obtained from the PH101 cell culture with a sandwich enzyme immunoassay. Moreover, the sIL-2R alpha secreted from the PH101 cells blocked the IL-2 dependent lymphocyte proliferation. These results indicate that the expression of IL-2R alpha on PH101 might suppress the IL-2 induced lymphocyte proliferation.

Cell Division↗
PubMed1993

Loss of VLA-2 collagen receptor in breast carcinoma, facilitating invasion and metastasis.

The integrin VLA-2 as a collagen receptor and VLA-5 as a fibronectin receptor were detected immunohistochemically in normal, benign tumor and carcinoma tissues of the breast. Both proteins were also detected by Western-blot analysis in some carcinoma cases. Epithelial and myoepithelial cells of both normal breast and benign tumor were in all cases immunoreactive for VLA-2 in the plasma membrane. Carcinoma cells in the invasive component were not immunoreactive for VLA-2 in 31 (46%) of 67 cases. Carcinoma cells in the intraductal components were negative for VLA-2 in only 4 (11%) of 36 cases, while 20 cases (56%) showed weak expression and 12 cases (33%) showed strong expression. Metastatic carcinoma cells in the lymph nodes of 6 cases showed no immunoreactivity except in one case, whereas, again with the exception of one case, the carcinoma cells in the primary tumors did show VLA-2 expression. With regard to VLA-5, there was no difference in its expression in the invasive components and the intraductal components. These findings suggest that the loss of VLA-2 plays a role in the invasion and metastasis of breast carcinoma.

Adult↗
PubMed1993

A role of VLA-6 laminin receptor in invasion of breast carcinoma.

The integrin VLA-6 as a laminin receptor and laminin as a ligand for laminin receptor were detected immunohistochemically in normal, benign tumor and carcinoma tissues of the breast. Epithelial cells of both normal breast and benign tumor were in almost all cases strongly immunoreactive for VLA-6 in the plasma membrane. Carcinoma cells in 34 of 70 cases (49%) with an invasive component were not immunoreactive for VLA-6, and no carcinoma cells showed strong positivity. Although carcinoma cells in only four of 51 cases (8%) with intraductal components were negative for VLA-6, 37 cases (72%) showed weak expression of VLA-6 and 10 cases (20%) showed strong expression of VLA-6. A concordant expression of VLA-6 on carcinoma cells and laminin around carcinoma cell nests with an invasive component was observed, and VLA-6 expression in carcinoma cells was correlated to tubular formation in carcinoma cell nests as an indicator of differentiation. These findings suggest that loss of VLA-6 plays a role in the invasion of breast carcinoma, and that VLA-6 laminin receptor and laminin may contribute to tubular differentiation of breast carcinoma cells.

Breast Diseases↗
PubMed1993

Myxoma of the breast: report of a case with unique histological and immunohistochemical appearances.

A case of myxoma of the breast is reported. The patient, a 19 year old Japanese woman, showed a lump in the left breast which had enlarged gradually over 3 years. A tumor measuring 5 x 5 x 4.5 cm was located mainly in the mammary parenchyma, but partially involved the overlying subcutaneous tissue. Histologically the tumor was multinodular and each nodule consisted of an abundant myxoid substance with a few spindle or stellate mesenchymal cells. The presence of hyaluronic acid was observed in the myxoid area, and a few constituent cells showed immunoreactivities for S-100 protein and alpha 1-antichymotrypsin. Electron microscopic studies revealed that some constituent cells looked like undifferentiated mesenchymal cells, while others showed a differentiation similar to fibroblast or histiocyte. These findings suggest that the constituent cells might derive from totipotential primitive mesenchymal cells.

Adult↗