Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1261473 (sarcoma)
 25,952 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multidrug resistance (MDR) is considered multifactorial and has been associated with overexpression of the multidrug resistance protein (MRP). However, effective compounds for reversal of MRP-related MDR are limited. In the present study, the modulatory activity of the novel pyridine analogue PAK-104P on MRP-mediated resistance to doxorubicin and paclitaxel was investigated in two doxorubicin-selected human tumor cell lines [HT1080/DR4 (sarcoma) and HL60/ADR (leukemia)] and compared with the nonimmunosuppressive cyclosporine analogue PSC-833. In cell lines HT1080/DR4 (MRP/lung resistance-related protein phenotype) and HL60/ADR (MRP phenotype), doxorubicin resistance was significantly higher (250-fold and 180-fold, respectively) than that to paclitaxel (6-fold and 9-fold, respectively). With noncytotoxic concentrations of PAK-104P (1 and 5 microM), the reversal of doxorubicin resistance was significant but partial in HT1080/DR4 and HL60/ADR cells (dose-modifying factor for 5.0 microM PAK-104P, 25.0 and 31.2, respectively), whereas complete reversal of paclitaxel resistance was achieved in HL60/ADR cells. In contrast, PSC-833 modulation of doxorubicin and paclitaxel resistance was modest. Cellular drug uptake and retention studies by flow cytometry analysis demonstrated that PAK-104P was effective in restoring cellular doxorubicin concentrations in resistant cells to levels comparable to those obtained in parental cells. In athymic nude mice, PAK-104P significantly potentiated the therapeutic efficacy of doxorubicin and paclitaxel against resistant HT1080/DR4 xenografts. Of significance is that the maximum tolerated doses of doxorubicin and paclitaxel were administered in combination with PAK-104P, documenting improvement in the therapeutic index of these agents. In addition to reversing P-glycoprotein-mediated MDR, the pyridine analogue PAK-104P provides an example of an effective in vivo modulator of MRP-mediated MDR.
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PMID:PAK-104P, a pyridine analogue, reverses paclitaxel and doxorubicin resistance in cell lines and nude mice bearing xenografts that overexpress the multidrug resistance protein. 981 80

This paper presents findings from uptake studies to evaluate the ability of an "artificial lymphatic system" (ALS) to enhance large and small molecular weight drug transport into solid tumors and the therapeutic effect of the additional drug on their growth. These studies also served to test the effectiveness of an implantable multidrain ALS. Walker 256, Neuroblastoma, and Sarcoma dual-tumor models were used to evaluate the effect of ALS aspiration on the uptake of 3F8 monoclonal antibody, and doxorubicin. A tumor shrinkage experiment using Walker 256 dual tumors was used to evaluate the efficacy of an implantable ALS with cyclophosphamide chemotherapy. Drug uptake significantly increased in all aspirated tumors; 3F8 uptake was enhanced 37.4% in the Walker and 93.1% in the Neuroblastoma tumor lines (p<0.05). Doxorubicin uptake increased 23.2% in Sarcoma tumor (p<0.05). The shrinkage study demonstrated that one-drain aspirated tumors shrank 90% faster (p<0.01) than control tumors, while three-drain aspirated tumors shrank 123% faster than control tumors (p<0.01).
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PMID:Enhancing the uptake of chemotherapeutic drugs into tumors using an "artificial lymphatic system". 1092 53

Doxorubicin-based chemotherapy is used in the treatment of sarcomas. Toxic side effects and poor response rates underline the demand for an improvement in current chemotherapeutic protocols. Recently, it has been reported that parvoviruses confer various antineoplastic properties to infected cells, and that adeno-associated virus type 2 (AAV-2) infection sensitizes malignant epithelial cells to radiation- or chemotherapy-based genotoxic treatment. Thus, we analyzed whether AAV-2 infection leads to an improved efficacy of doxorubicin chemotherapy in malignant mesenchymal cells, using 13 human sarcoma cell lines. Therapeutic effects were analyzed by measuring cell viability and proliferation (WST-1, colony forming, and propidium iodide assays). Additionally, permissivity for AAV-2 infection was determined by Southern dot blot analysis. AAV-2 infection strongly increased the efficacy of doxorubicin treatment in rhabdomyo-, fibro-, osteo- and chondrosarcoma cells in a dose-dependent manner. This effect was not observed in liposarcoma and synovial sarcoma cells, although a susceptability to AAV-2 infection was documented. Our results indicate that the sensitization effects towards genotoxic treatment exerted by non-pathogenic AAV-2 infection are not restricted to epithelial malignancies but may also be exploited for the improvement of chemotherapy in patients suffering from rhabdomyo-, fibro-, osteo-, or chondrosarcomas.
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PMID:Sensitization of sarcoma cells to doxorubicin treatment by concomitant wild-type adeno-associated virus type 2 (AAV-2) infection. 1201 1

Twenty-one children (16 males, 5 females) with malignant primary hepatic tumors were admitted to the Pediatric Clinic of the University of Bologna between June 1973 and July 2001. The diagnosis was hepatoblastoma (HBL) in 16 cases; hepatocellular carcinoma (HCA) in 3 cases; undifferentiated sarcoma in 1, malignant rhabdoid tumour of the liver in 1. Median age at diagnosis was 1.8 year (1 mounth-13 years). As to intrahepatic tumor's extension, patients were classified in groups (from I to IV) according to International Society of Pediatric Oncology staging. 2 patients were ascribed to group I; 9 to group II; 9 to group III and I to group IV. At diagnosis 3 pts presented lung metastases. Seventeen patients (81%) were treated with surgery, in 11 cases as first approach to the tumor. In 10 patients, initially with unresesectable tumor, chemotherapy was started first. Drugs used were mostly Cisplatinum or Carboplatinum with Doxorubicin. Sussequently 6 patients were submitted to surgery. At a median follow up of 12.5 years, 52.3% of patients is alive without disease. This percentage rises to 58% taking into consideration only HBL and HCA cases (alive 11/19). We conclude that excluding metastases at diagnosis (3 deaths), the main prognostic factor is resectability and radical surgery: in our experience 4 patients with unresectable tumor died, as 2 patients with microscopical residual after surgery.
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PMID:[Malignant primary tumors of the liver in childhood]. 1223 33

More than 80% of patients with extremity sarcoma ultimately develop metastases to pulmonary sites. Doxorubicin alone or in combination with other chemotherapeutic agents may result in partial or complete tumor response for sarcoma pulmonary metastases. Regardless of the response, there has been no proven survival benefit from cytotoxic chemotherapy in the treatment of localized or metastatic soft tissue sarcoma. Insulin-like growth factor-I receptor (IGF-I-R) activation may contribute to resistance to chemotherapy in mesenchymal neoplasia. IGF-I-R activation by its ligand decreases in vitro cytotoxic response of sarcoma to doxorubicin, the most active agent against soft tissue sarcoma in adults. Furthermore, IGF-I-R is frequently overexpressed in soft tissue sarcoma and may predict poor response to traditional chemotherapy. The effect of doxorubicin on a human soft tissue sarcoma cell derived from a dedifferentiated lung metastasis was evaluated using titrated doxorubicin doses with and without exogenous IGF-I (100 ng/ml). Western blot analysis was performed to evaluate levels of phosphorylated IGF-I-R under control and experimental conditions. In vitro proliferation assays were performed. Nuclear activation through IGF-I receptor mediated pathways prior to exposing sarcoma cells to doxorubicin altered the pattern of response to doxorubicin with enhanced mitogenesis (>2-fold) and blunted doxorubicin cytotoxicity (>10% change in IC50). These data suggest that activation of IGF-I receptor in sarcoma cells is a potential mechanism for tumor resistance to doxorubicin. Inhibition of IGF-I receptor activation represents a novel approach to enhance the degree and duration of response to traditional chemotherapy against soft tissue sarcoma.
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PMID:Insulin-like growth factor-I receptor activation blocks doxorubicin cytotoxicity in sarcoma cells. 1246 67

Doxorubicin is an antineoplasic agent active against sarcoma pulmonary metastasis, but its clinical use is hampered by its myelotoxicity and its cumulative cardiotoxicity, when administered systemically. This limitation may be circumvented using the isolated lung perfusion (ILP) approach, wherein a therapeutic agent is infused locoregionally after vascular isolation of the lung. The influence of the mode of infusion (anterograde (AG): through the pulmonary artery (PA); retrograde (RG): through the pulmonary vein (PV)) on doxorubicin pharmacokinetics and lung distribution was unknown. Therefore, a simple, rapid and sensitive high-performance liquid chromatography method has been developed to quantify doxorubicin in four different biological matrices (infusion effluent, serum, tissues with low or high levels of doxorubicin). The related compound daunorubicin was used as internal standard (I.S.). Following a single-step protein precipitation of 500 microl samples with 250 microl acetone and 50 microl zinc sulfate 70% aqueous solution, the obtained supernatant was evaporated to dryness at 60 degrees C for exactly 45 min under a stream of nitrogen and the solid residue was solubilized in 200 microl of purified water. A 100 microl-volume was subjected to HPLC analysis onto a Nucleosil 100-5 microm C18 AB column equipped with a guard column (Nucleosil 100-5 microm C(6)H(5) (phenyl) end-capped) using a gradient elution of acetonitrile and 1-heptanesulfonic acid 0.2% pH 4: 15/85 at 0 min-->50/50 at 20 min-->100/0 at 22 min-->15/85 at 24 min-->15/85 at 26 min, delivered at 1 ml/min. The analytes were detected by fluorescence detection with excitation and emission wavelength set at 480 and 550 nm, respectively. The calibration curves were linear over the range of 2-1000 ng/ml for effluent and plasma matrices, and 0.1 microg/g-750 microg/g for tissues matrices. The method is precise with inter-day and intra-day relative standard deviation within 0.5 and 6.7% and accurate with inter-day and intra-day deviations between -5.4 and +7.7%. The in vitro stability in all matrices and in processed samples has been studied at -80 degrees C for 1 month, and at 4 degrees C for 48 h, respectively. During initial studies, heparin used as anticoagulant was found to profoundly influence the measurements of doxorubicin in effluents collected from animals under ILP. Moreover, the strong matrix effect observed with tissues samples indicate that it is mandatory to prepare doxorubicin calibration standard samples in biological matrices which would reflect at best the composition of samples to be analyzed. This method was successfully applied in animal studies for the analysis of effluent, serum and tissue samples collected from pigs and rats undergoing ILP.
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PMID:A validated assay for measuring doxorubicin in biological fluids and tissues in an isolated lung perfusion model: matrix effect and heparin interference strongly influence doxorubicin measurements. 1455 Aug 66

The management of soft tissue sarcomas has been highlighted in the last few years by the responsiveness of gastrointestinal stromal tumors to imatinib (Gleevec, Novartis). In this article, the use of chemotherapeutic agents in the management of this and some of the 50 or more subtypes of sarcomas are discussed, and a brief review of the use of chemotherapy in the adjuvant or neoadjuvant setting for people with large extremity sarcomas is provided. Doxorubicin and ifosfamide (Mitoxana, Bristol-Myers Squibb) remain the best individual drugs for sarcomas overall, although dacarbazine and gemcitabine (Gemzar, Eli Lilly) with or without a taxane has activity in at least a subset of sarcomas. The data regarding adjuvant chemotherapy for extremity soft tissue sarcomas is still quite mixed, with little if any overall survival advantage found to support its incorporation into disease management. The finding of tyrosine kinase inhibitors such as imatinib with demonstrated activity in gastrointestinal stromal tumors and dermatofibrosarcoma protuberans, as well as the finding of new agents such as ecteinascidin-743 (Yondelis, PharmaMar) with at least some activity against soft tissue sarcomas, reinforces the idea that we should target individual subtypes of sarcoma, just as treatment varies by subtype for the hematological malignancies.
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PMID:Role of chemotherapy in patients with soft tissue sarcomas. 1505 53

Peripheral primitive neuroectodermal tumor (PNET) belongs to the PNET/Ewing's sarcoma family. PNET is a small round cell tumor of putative neuroectoderm origin and is the second most common sarcoma among children and young adults. It may occur anywhere in the body and within any age group; however, it is most likely to occur in the bone and soft tissues. There have been a small number of case reports of PNET arising in the ovary. We presented a case of PNET arising in the right ovary of an 18-year-old woman. The tumor was metastased to the lymph nodes of the pelvis and para-aorta at surgical staging. We had persecuted Taxol/carboplatin chemotherapy, pelvic cavity radiotherapy, and Vincristine/Actinomycin, Cyclophosphamide/Doxorubicin (VACA). She died after 10 months due to septic shock.
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PMID:A case of peripheral primitive neuroectodermal tumor of the ovary. 1508 40

BACKGROUND: Soft tissue sarcomas comprise less than 1% of all solid malignancies. The presentation and behavior of these tumors differs depending on location and histological characteristics. Standard therapy consists of complete surgical resection in combination with adjuvant radiotherapy. The role of chemotherapy is not clearly defined and is largely restricted to clinical trials. Only a limited number of agents have proved to be effective in soft tissue sarcomas. The use of doxorubicin, epirubicin and ifosfamide allowed response rates of more than 20%. In addition, recent chemotherapy trials did not demonstrate any significant differences in efficacy for various histological subtypes. METHODS: The objective of this study was to gain additional information about the chemosensitivity of soft tissue sarcomas to seven 7 different chemotherapy agents as single drugs and 4 combinations. Therefore we used an established ATP based in-vitro testing system and examined 50 soft tissue sarcomas. Chemosensitivity was assessed using a luciferin-luciferase-based luminescence assay providing individual chemosensitivity indices for each agent tested. RESULTS: The sensitivity varied widely according to the histological subtypes. The tumors state of cellular dedifferentiation played a crucial role for the efficiency of the chemotherapeutic agents. The sensitivity also depended on the presentation of the sarcoma as a primary or recurrent tumor. The highest sensitivity was demonstrated for actinomycin D as a single agent, with 74% of the tumor samples exhibiting a high-grade sensitivity (20% low sensitivity, no resistance). The combination of actinomycin D and ifosfamide yielded a high sensitivity in 76% (2% resistance). Doxorubicin as a mono-therapy or in combination with ifosfamide achieved high sensitivity in 70% and 72%, respectively, and resistance in 6% of the samples. CONCLUSION: Chemosensitivity testing is feasible in soft tissue sarcomas. It can be used to create sensitivity and resistance profiles of established and new cytotoxic agents and their combinations in soft tissue sarcomas. Our data demonstrate measurable discrepancies of the drug efficiency in soft tissue sarcomas, sarcoma subtypes and tumor recurrencies. However, current therapeutic regime does not take this in consideration, yet.
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PMID:Feasibility of chemosensitivity testing in soft tissue sarcomas. 1583 92

Doxorubicin and ifosfamide are the two most active drugs in the treatment of patients with advanced, soft tissue sarcoma (STS) of most histologic subtypes, aside from gastrointestinal stromal tumor (GIST). However, after failure of these drugs, alone or in combination, patients with advanced STS have few therapeutic options and the search for new active drugs is well worth pursuing. ET-743, a DNA minor groove binder, which blocks cell cycle progression in G2/M phase through a p53-independent apoptotic process, represents the most promising among novel compounds in STS, since recently completed phase II trials have consistently shown high survival, in spite of the relatively low incidence of major objective responses. The potential for combination with other active compounds further increases the appeal of ET-743. Imatinib mesylate is being tested also in STS other than GIST, which can overexpress one or more of the tyrosine kinases inhibited by imatinib; however, negative data have recently been presented. Clinical studies with a number of other compounds are ongoing or planned. However, investigators involved in the management of patients with advanced STS are to be increasingly aware of the emergence of new molecular targets and genetic profiles in different histologic subtypes, according to which treatment strategies should be adapted.
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PMID:New emerging drugs in soft tissue sarcoma. 1653 4


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