Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Methotrexate (MTX) in high doses (3 to 7.5 g/m2) with leucovorin rescue (HDMTX-LCV) can be delivered on a weekly basis in a setting of proper pharmacologic monitoring. Myelosuppression occurs in 28 per cent of the patients and in 8 per cent of the courses and usually results from delayed MTX excretion secondary to mild reversible nephrotoxicity. The incidence of tumor regression was 50 per cent in head and neck cancer; 59 per cent in non-Hodgkin's lymphoma; 40 per cent in small cell lung cancer; 24 to 50 per cent in breast cancer and 50 per cent in osteogenic carcinoma, for an over-all response rate of 39 per cent (70 of 178) in patients with disseminated cancer. HDMTX-LCV is not recommended for the conventional treatment of metastatic cancer because of the potential for toxicity and the fact that the response rates cited are probably not superior to those which can be achieved by conventional doses of MTX. However, the relative lack of myelosuppression and mucositis, when compared to conventional unrescued MTS, and the achievement of therapeutic concentrations of MTX in the central nervous system with the HDMTX-LCV program have led to its incorporation into clinical trials of combination chemotherapy.
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PMID:High dose methotrexate with leucovorin rescue. Rationale and spectrum of antitumor activity. 696 19

Breast cancer has a prodigious capacity to metastasize to bone. In women with advanced breast cancer and bone metastases, bisphosphonates reduce the incidence of hypercalcaemia and skeletal morbidity. Recent clinical findings suggest that some bisphosphonates reduce the tumour burden in bone with a consequent increase in survival, raising the possibility that bisphosphonates may have a direct effect on breast cancer cells. We have investigated the in vitro effects of bisphosphonates zoledronate, pamidronate, clodronate and EB 1053 on growth, viability and induction of apoptosis in three human breast cancer cell lines (MDA-MB-231, Hs 578T and MCF-7). Cell growth was monitored by crystal violet dye assay, and cell viability was quantitated by MTS dye reduction. Induction of apoptosis was determined by identification of morphological features of apoptosis using time-lapse videomicroscopy, identifying morphological changes in nucleis using Hoechst staining, quantitation of DNA fragmentation, level of expression of bcl-2 and bax proteins and identification of the proteolytic cleavage of Poly (ADP)-ribose polymerase (PARP). All four bisphosphonates significantly reduced cell viability in all three cell lines. Zoledronate was the most potent bisphosphonate with IC50 values of 15, 20 and 3 microM respectively in MDA-MB-231, MCF-7 and Hs 578T cells. Corresponding values for pamidronate were 40, 35 and 25 microM, whereas clodronate and EB 1053 were more than two orders of magnitude less potent. An increase in the proportion of cells having morphological features characteristic of apoptosis, characteristic apoptotic changes in the nucleus, time-dependent increase in the percentage of fragmented chromosomal DNA, down-regulation in bcl-2 protein and proteolytic cleavage of PARP, all indicate that bisphosphonates have direct anti-tumour effects on human breast cancer cells.
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PMID:Bisphosphonates induce apoptosis in human breast cancer cell lines. 1078 May 27

Although docetaxel (Taxotere; TXT), a taxoid anticancer drug, is clinically and experimentally very effective against breast cancer, its antitumor effect is of very short duration. We addressed whether 5-fluorouracil (5-FU) and its derivatives can act synergistically with TXT against mammary tumors, with placing particular stress on their use by oral route. Mouse mammary tumor cell line, MM2, was propagated in culture and as ascites in mice. Carmofur (HCFU) and doxifluridine (5'-DFUR) were used as 5-FU derivatives. In vitro, the cytotoxic effects of antitumor drugs on MM2 cells were examined by MTS assay. In vivo, mice inoculated i.p. with MM2 cells were treated with i.p. injection of TXT and/or oral administration of 5-FU or its derivatives, and observed for curing tumor. In vitro, the synergistic effects were observed in the combination of TXT and 5-FU or HCFU, but not in that of TXT and 5'-DFUR. In vivo, all of these combinations cured tumors far more effectively than TXT alone. The discrepant result of the combination of TXT and 5'-DFUR between in vitro and in vivo was ascribed to up-regulation of pyrimidine phosphorylase in tumor cells in vivo by TXT. Thus, 5-FU, its masked compounds like HCFU and its prodrugs like 5'-DFUR can act synergistically with TXT in the therapy of cancer even when administered by the oral route.
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PMID:Docetaxel alone or orally combined with 5-fluorouracil and its derivatives: effects on mouse mammary tumor cell line MM2 in vitro and in vivo. 1160 57

Thymidylate synthase (TS) is responsible for the de novo synthesis of thymidylate, which is required for DNA synthesis and repair and which is an important target for fluoropyrimidines such as 5-fluorouracil (5-FU), and antifolates such as Tomudex (TDX), ZD9331, and multitargeted antifolate (MTA). To study the importance of TS expression in determining resistance to these agents, we have developed an MDA435 breast cancer-derived cell line with tetracycline-regulated expression of TS termed MTS-5. We have demonstrated that inducible expression of TS increased the IC(50) dose of the TS-targeted therapeutic agents 5-FU, TDX, and ZD9331 by 2-, 9- and 24-fold respectively. An IC(50) dose for MTA was unobtainable when TS was overexpressed in these cells, which indicated that MTA toxicity is highly sensitive to increased TS expression levels. The growth inhibitory effects of the chemotherapeutic agents CPT-11, cisplatin, oxaliplatin, and Taxol were unaffected by TS up-regulation. Cell cycle analyses revealed that IC(50) doses of 5-FU, TDX and MTA caused an S-phase arrest in cells that did not overexpress TS, and this arrest was overcome when TS was up-regulated. Furthermore, the S-phase arrest was accompanied by 2- to 4-fold increased expression of the cell cycle regulatory genes cyclin E, cyclin A, and cyclin dependent kinase 2 (cdk2). These results indicate that acute increases in TS expression levels play a key role in determining cellular sensitivity to TS-directed chemotherapeutic drugs by modulating the degree of S-phase arrest caused by these agents. Moreover, CPT-11, cisplatin, oxaliplatin, and Taxol remain highly cytotoxic in cells that overexpress TS.
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PMID:Characterization of a thymidylate synthase (TS)-inducible cell line: a model system for studying sensitivity to TS- and non-TS-targeted chemotherapies. 1170 73

Breast cancer is a rare, but frequently hidden pathology. A woman, 36 years old, during the early months of pregnancy found a little tumor in her right breast. A fine needle biopsy was negative for cancer. Despite this, the tumor rose and two months after delivery (the patient breast-fed her daughter for a month), she had pain in the right axillary region and the tumors involved all superior dials of the right breast. A Madden mastectomy was performed. The histopathological report was: ductal invasive breast cancer 3 of 19 lymph nodes involved, stage IIIA, TNM pT3N2M0, ER -, PgR +--. Chemotherapeutic regimens were: at first ADM 75 mg/m2 for 5 cycles, and after CMF 1-8 for 6 cycles. After six months the woman had a cutaneous recurrence in the scar of mastectomy, treated with surgery and RT. Thirteen months after, she had lung MTS and then brain MTS. The patient died thirty months after the mastectomy. The surgeons have to discover the women high-risk for the breast cancer before and during the pregnancy. Excisional biopsy is the diagnostic procedure of choice for breast lump during pregnancy. When a breast cancer develops during a pregnancy, the surgeon has to operate immediately the tumors. Chemotherapeutic regimens should be delayed until the second o third trimester or after delivery.
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PMID:[Breast carcinoma in pregnancy: a clinical case]. 1240

Exemestane, a non-steroidal aromatase inhibitor that shuts down estrogen synthesis, and paclitaxel, an antineoplastic drug, inhibiting microtubule formation and interfering with the cells potential to proliferate, are well established treatments for metastatic breast cancer. Given that exemestane is a treatment for hormone-sensitive tumors in postmenopausal women with more favorable prognosis, while paclitaxel is normally used for women suffering from hormone-insensitive breast cancers with less favorable prognoses, there is currently no experience with the combination of the two drugs. In order to find out to what extent exemestane and paclitaxel add to each other's effects when given concomitantly, the effect of the two drugs alone and in combination on the growth of various gynecological tumor cell lines was assessed. Tumor cell growth was measured according to the cell titer cell proliferation technique, also referred to as the MTS assay, by measurement of relative cell numbers. In gynecological cancer cells expressing aromatase, the effect of a treatment with paclitaxel (10 nM) on cell growth was enhanced by co-treatment with exemestane. This additive effect was independent of ERalpha expression, but dependent on the presence of androstenedione. It was observed in HEC-1A and Ishikawa endometrial adenocarcinoma cells as well as in SK-OV-3 ovarian cancer and in MDA-MB-231 breast cancer cells. Our findings suggest that a combination of paclitaxel with exemestane might be beneficial for the treatment of aromatase-positive gynecological cancer, because it may allow us to reduce the paclitaxel dosage and therefore the toxicity of the treatment.
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PMID:Effects of a combination of exemestane and paclitaxel on human tumor cells in vitro. 1509 Jul 44

Changes in the intracellular level of reactive oxygen species (ROS) including superoxide anion, hydroxyl radical, hydrogen peroxide and finally cellular acid-base equilibrium are reported to play an important role in the early step of apoptosis. All of which would precede the loss of mitochondrial membrane potential and releasing of those apoptotic inducing factors such as cytochrome c as well as caspases activation. Any potential chemotherapeutic agent that could drive such changes in ROS would be particularly attractive. Recently we have reported the potential use of Gleditsia sinensis extract (GSE) in cancer therapy including solid tumour and leukaemia cell lines as well as primary cultured leukaemia cells in vitro. We demonstrated that apoptotic activity is involved. Here we further showed that the mechanism of GSE induced apoptosis, including an early decreasing of intracellular superoxide anion as measured by nitroblue tetrazolium (NBT) reduction assay. This phenomenon readily occurred before any shrinkage of cancer cells including MDA-MB231 breast cancer, CNE-2 nasopharyngeal carcinoma, K-562 chronic myelogenous leukaemia and KG1-a, acute myelogenous leukaemia. Cell viability was determined by morphological investigation and the [3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] (MTS) assay. Furthermore, the superoxide dismutase activity from those cellular extracts after GSE treatment seemed to be increased. Taken together, we speculate that the GSE-induced apoptosis, via ROS pathway, involves an early decrease of intracellular superoxide anion.
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PMID:Superoxide anion is involved in the early apoptosis mediated by Gleditsia sinensis fruit extract. 1513 34

The effective microorganism (EM-X) fermentation extract is derived from rice bran and seaweed extract. It has been shown to possess anti-oxidation activity both in vitro and in vivo. To our knowledge, the possible in vitro anti-cancer potential of EM-X has not been demonstrated. Here we showed that the double concentrate of EM-X (EM-X2) at concentrations of 20-30% by volume, had growth inhibitory activity on MDA-MB231 breast cancer cell line and K-562 chronic myelogenous leukaemia cell lines by [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2-H-tetrazolium, inner salt] (MTS) assay. No characteristic features of apoptosis could be observed morphologically. Colony formation assay illustrated that both MDA-MB231 breast cancer and K-562 CML cells lost part of their regeneration potential after treatment with EM-X2 at 30% concentration by volume for 24 h. At these concentrations, only slight growth inhibitory effect was observed in 293 human kidney fibroblast cells and in three non-malignant bone marrows. Intracellular nitro blue tetrazolium (NBT) reduction assay showed that both MDA-MB231 breast cancer and K-562 CML cells had about 30% reduction of intracellular NBT after incubation with 30% of EM-X2. Increased activity of superoxide dismutase (SOD) could be detected from both MDA-MB231 and K-562 cell lines after incubating with 30% of EM-X2. Taken together, our data suggested that EM-X could inhibit growth and reduce the regeneration potential of cancer cells, possibly through its antioxidation activity.
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PMID:Growth inhibitory potential of effective microorganism fermentation extract (EM-X) on cancer cells. 1549 67

HER2 is the target of a new treatment for metastatic breast cancer using the humanized monoclonal antibody (MAb) trastuzumb (Herceptin). A novel alpha-particle emitting (213)Bi-Herceptin construct, targeting the HER2 extracellular domain on breast cancer cells, was produced by chelation and characterized in vitro in this study. We used Western blot and flow cytometry analysis to examine the expression of HER2 in a panel of established human metastatic breast cancer cell lines (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt) MTS assay to evaluate the cytotoxicity and the TUNEL assay to analyze cellular apoptosis. Our results demonstrate that the human breast cancer cell lines BT-474 and SK-BR-3 express high levels of HER2 protein while MDA-231 expresses low levels of HER2. (213)Bi-Herceptin alpha conjugate (AC) was specifically cytotoxic to these cell lines in a HER2 level-dependent fashion, resulting in the cellular death through apoptosis. These results suggest that (231)Bi-Herceptin AC could be a novel agent for the treatment of breast cancer cell clusters or micro-metastases with high levels of HER2 expression.
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PMID:Cytotoxicity of breast cancer cells overexpressing HER2/neu by 213Bi-Herceptin radioimmunoconjugate. 1567 Aug 95

2-Methoxyoestrogen sulphamates are a new class of compounds, which inhibit breast cancer cell proliferation and are also potent inhibitors of steroid sulphatase (STS) activity. In the present study, we have used two cell proliferation assays (MTS and AB) to identify potent new compounds in this class. Similar IC(50) values were obtained using these assays with two of the most potent compounds identified being 2-methoxyoestradiol-bis-sulphamate (2-MeOE2bisMATE) and 2-methoxyoestradiol-17beta-cyanomethyl-3-O-sulphamate (2-MeOE2CyMATE). Both compounds inhibited the proliferation of MCF-7 (ER+) and MDA-MB-231 (ER-) breast cancer cells. Using the AB assay, which allows repeat measurements of cell proliferation without killing cells, both compounds were shown to inhibit cell proliferation in an irreversible manner. As STS may be involved in the removal of the sulphamoyl moiety of these compounds, which could reduce their potency, their ability to inhibit the proliferation of MCF-7 cells transfected with the cDNA for STS was also examined. Although the STS activity was 20-fold higher in these cells than in non-transfected MCF-7 cells, no decrease in the ability of these compounds to inhibit cell proliferation was detected. To test the efficacy of these compounds in vivo, nude mice were inoculated with MCF-7 cells in Matrigel and stimulated to grow with oestradiol. Three weeks after the oral administration of 2-MeOE2bisMATE or 2-MeOE2CyMATE (20mg/kg/day, 5 days/week) tumour volumes had regressed by 52% and 22%, respectively. Both compounds also inhibited liver and tumour STS activity by >90%. The potent anti-proliferative effects of these compounds, and their ability to inhibit tumour growth and STS activity in vivo, indicates that they are suitable for development as novel therapeutic agents, which should be active against a wide range of cancers.
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PMID:The effects of 2-methoxyoestrogen sulphamates on the in vitro and in vivo proliferation of breast cancer cells. 1586 69


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