Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Between April 1986 and March 1989, ten patients under 21 years of age with histologically confirmed malignant astrocytoma, received marrow-ablative chemotherapy with either thiotepa and Etoposide (five patients) or thiotepa, Etoposide and BCNU (five patients), followed by bone marrow 'rescue'. Nine patients had glioblastoma multiforme (GBM), and one patient had an intrinsic brain stem anaplastic astrocytoma (AA). Seven patients were treated for recurrent tumor. Two patients who developed GBM as second malignancies were treated directly following surgical resection. One patient had received irradiation only for recently diagnosed cervical spinal cord GBM. Thiotepa was administered at a total dose of 600-900 mg/M2 over three days, Etoposide was administered at a total dose of 1500 mg/M2 over three days, and BCNU was administered at a total dose of 600 mg/M2 over four days. Non-hematopoietic toxicities have been mainly transient, predictable and acceptable, consisting of oropharyngeal mucositis, cutaneous hyperpigmentation, erythema and desquamation. Four patients achieved complete responses (CR), as determined by radiographic evaluation (CT and/or MRI) on day 28 post-marrow infusion. The mean remission duration of those with CR is 290+ days; two patients presently remain in remission. Two patients achieved partial responses (PR, greater than 50% tumor shrinkage) by day 28 post-marrow infusion; both developed disease progression, at day 61 and 94 post-marrow infusion, respectively. One patient, with a brain stem AA, had stable disease maintained for 13 months post-marrow infusion. With a total (CR + PR) response rate of 60%, these regimens merit evaluation in broader categories of recurrent brain tumor patients, as well as in patients with newly-diagnosed GBM.
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PMID:High-dose multi-agent chemotherapy followed by bone marrow 'rescue' for malignant astrocytomas of childhood and adolescence. 196 62

The interaction of etoposide (VP-16), Vinca alkaloids, and verapamil with the P-glycoprotein (P-gp) was studied in human breast (MCF-7) and Chinese hamster lung (DC3F) cell lines and the corresponding multidrug-resistant MCF-7/ADR and DC3F/ADX tumor cell lines, selected for resistance to Adriamycin and actinomycin D, respectively, and overexpressing P-gp. Verapamil (10 microM) markedly reversed resistance to vincristine (11-fold in DC3F/ADX and 125-fold in MCF-7/ADR; 1-hr exposure), but it had a very modest effect on resistance to VP-16 (3- to 4-fold; 1-hr exposure). Resistant cells accumulated 2- to 4-fold less VP-16 and vincristine than the parental cell lines. Verapamil (10 microM) significantly increased accumulation and retention of vincristine, but not of VP-16, in resistant cell lines. Photoaffinity labeling of resistant cell lines with radioactive analogs of verapamil [N(p-azido-3-125I-salicyl)-N'-beta-aminoethylverapamil (NASVP)] and vinblastine[N-(p-azido-3-125I-salicyl)-N'-beta-aminoethylvindesine (NASV)] showed distinctly labeled P-gp bands in both resistant cell lines, compared with wild-type cells. Excess nonradioactive vinblastine or verapamil effectively competed with the P-gp photolabeling by either NASVP or NASV, with IC50 levels of 0.6 and 10 microM, respectively. In contrast, nonradioactive VP-16 was 100- to 500-fold less potent than vinblastine in competing with P-gp photolabeling, suggesting that VP-16 has significantly lower affinity for P-gp than Vinca alkaloids have. Taken together, our data indicate that P-gp glycoprotein by itself may not be important in the transport/efflux of VP-16 and, thus, in the mechanism of resistance to VP-16 in these cells.
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PMID:P-glycoprotein-independent mechanism of resistance to VP-16 in multidrug-resistant tumor cell lines: pharmacokinetic and photoaffinity labeling studies. 197 71

Cremophor EL (polyoxyethylene castor oil) and Tween 80, used as solvents for cyclosporin A and VP-16, respectively, were found to reverse the multidrug resistant (MDR) phenotype. In daunorubicin (DNR) resistant Ehrlich ascites tumor cells (EHR2/DNR+), both solvents at percentages of 0.01% (v/v) enhanced DNR accumulation to sensitive levels. Cremophor EL and Tween 80 did not influence DNR accumulation in drug-sensitive cells (EHR2). The concentration of cyclosporin A alone that enhanced DNR accumulation in EHR2/DNR+ cells to sensitive levels was 5 micrograms/mL whereas 0.2 micrograms/mL of cyclosporin A dissolved in 0.001% (v/v) Cremophor EL enhanced DNR accumulation to sensitive levels, thus indicating synergy between Cremophor EL and cyclosporin A. Cyclosporin A had a negligible effect on DNR accumulation in the drug-sensitive cells. In clonogenic assays, the LD10 of DNR was 1 microM in EHR2/DNR+ cells. Combining 1 microM DNR with non-toxic amounts of Cremophor EL (0.001% and 0.002%, v/v) potentiated the cytotoxicity of DNR and resulted in a cell kill of 77% and 86%, respectively, in the resistant cells. In non-toxic amounts, CrEL and Tween 80 acted synergistically with reduced concentrations of verapamil, resulting in DNR accumulation approaching close to the sensitive level. Azidopine photoaffinity labeling of P-glycoprotein in plasma membrane vesicles from EHR2/DNR+ cells was inhibited 100% and 80%, by 0.003% (v/v) Cremophor EL or Tween 80, respectively. These data permit the conclusion that non-toxic amounts of CrEL and Tween 80 modulated DNR resistance by raising intracellular DNR levels, due to their abilities to bind to the plasma membrane P-glycoprotein.
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PMID:The solvents cremophor EL and Tween 80 modulate daunorubicin resistance in the multidrug resistant Ehrlich ascites tumor. 197 41

This paper describes the cellular and tissue distribution of P-glycoprotein (P-GP) (mdr1 gene product), the role of P-GP in vivo and immunodiagnosis of multi-drug-resistant cancers. We mainly used MRK 16 monoclonal antibody (MAb) reactive with P-GP. P-GP was found to be expressed very strongly in the adrenal cortex of adults and strongly in the renal tubules of the kidney, capillary blood vessels of the brain, and also in placenta. Interestingly, P-GP was not distributed in fetal and neonatal adrenals, and thus may be closely related to adrenal maturation. A high level of P-GP expression was also seen in all cases of functional hormone-producing adrenal tumor, one case of insulinoma, two cases of untreated colonic cancer, one case each of untreated lung cancer, gastric cancer and breast cancer, six cases of renal cell carcinoma and 17 cases of bladder cancer. Using flow cytometry and immunocytochemistry, we investigated the reactivity of MRK 16 MAb with peripheral human mononuclear cells (mainly blastic cells and lymphocytes) from 31 patients with leukemia or malignant lymphoma. Reactivity with MRK 16 MAb was observed in five cases. Some cases reflected the prior administration of adriamycin, vincristine and VP-16, which are known to induce P-GP expression. P-GP-MRK 16-protein A-Sepharose complex derived from human adrenal possessed marked ATPase activity. These data suggest that P-GP may play a physiological role in the human adrenal. Finally, diagnostic criteria of multi-drug-resistant cancers are presented.
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PMID:Expression and functions of P-glycoprotein (mdr1 gene product) in normal and malignant tissues. 197 61

48 patients with advanced sarcomas were treated with regional hyperthermia (RHT) and systemic chemotherapy (ifosfamide/VP-16). 92% of the patients had been pretreated before entering the study. Pretreatment consisted of chemotherapy (33/48), surgery (9/48) or surgery plus irradiation (2/48). Following the conventional treatment, the patients had either relapsed (30/48) or had shown progressive disease (14/48) at the primary site with or without metastases. In 43 patients the overall response rate [5 complete responders (CR) and 6 partial responders (PR)] was 26%, 17 patients revealed no change (NC) and 15 patients showed local tumor progression (PD). A significant correlation of tumor response (responders [CR + PR] versus non-responders [PD]) with intratumoral averaged temperatures could be observed.
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PMID:[Regional deep hyperthermia of sarcoma for improving local tumor control]. 198 80

Etoposide (VP-16-213) is an antineoplastic agent with demonstrated efficacy against a broad spectrum of human malignancies, including testicular, germ cell, lung, and other cancers. Etoposide can be synergistic with other agents. As part of combination chemotherapy, etoposide has become a so-called standard in therapies for testicular cancer and small cell lung cancer. Its activity in tumors such as lymphoma and leukemia, as well as solid tumors, identifies etoposide as a highly important chemotherapeutic agent. Cellular and animal models have shown that the cell kill and tumor response depend on both dose and time of exposure. Recent clinical studies again show that dose and schedule of etoposide can have important effects on clinical response to the drug. Further research should now continue: (1) on the use of etoposide as part of initial therapy in several cancers, and (2) in higher doses and prolonged schedules to optimize this agent's potential.
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PMID:Etoposide. Current and future status. 198 22

Neuraxis radiation therapy (RT) for primary intracranial tumors is associated with major late effects if administered to very young children. To control residual tumor and to delay RT, we treated eight young children (median age 6.5 months) with primary central nervous system (CNS) tumors using combination chemotherapy: cisplatin, 20 mg/M2/day plus VP-16, 75 mg/M2/day i.v. for 5 days, given q. 3-6 weeks for 8 cycles. The tumors were medulloblastoma (one), malignant ependymoma (two), primitive neuroectodermal tumor PNET (two), malignant glioma (two), astrocytoma (one). Six had measurable disease; three had positive cerebrospinal fluid (CSF) cytopathology. All patients with measurable tumor had initial objective responses (three) complete response [CR], one partial response [PR], two minor response [MR], including cytopathology (three CR of three) and metastatic deposits (two CR of two). One patient relapsed during chemotherapy. Median time to disease progression was 17.5 months; median survival was 34 months. Three patients, none of whom received RT, have prolonged progression-free intervals of 47-67 months to date. Neurodevelopmental progress continued during and after chemotherapy. Chemotherapy toxicity was mild. Median neutrophil nadir was 312/mm3, platelets 72,000. Fever during neutropenia occurred in six of 61 courses. Moderate high-frequency auditory losses were detected in three patients, and mild renal injury (GFR less than 70 ml/min) was detected in two of seven evaluable children. This pilot study demonstrates the apparent efficacy and mild toxicity of 5 day courses of cisplatin plus VP-16, with delayed RT, in young children with CNS neoplasms. A POG treatment protocol that incorporates cisplatin plus VP-16 is evaluating primary chemotherapy with delayed radiotherapy in larger numbers of pediatric brain tumor patients.
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PMID:Efficacy of postoperative chemotherapy using cisplatin plus etoposide in young children with brain tumors. 199 Feb 53

The synergistic interaction of etoposide with cisplatin in certain tumors prompted an evaluation of its potential role in the i.p. treatment of ovarian cancer and other intraabdominal malignancies. We conducted a Phase I evaluation of etoposide as a single agent to determine the maximum tolerated dose i.p., to describe dose-limiting and other toxic effects, and to examine the pharmacokinetics of etoposide in this setting. Etoposide was diluted in 2 liters of normal saline, and instilled i.p. over 10 to 25 min following maximal drainage of ascites. The dwelling time was 4 h, followed by peritoneal drainage. Twenty-two patients received 56 courses at doses which ranged from 100 to 800 mg/m2. The median age was 49, the median performance status was 1, and 18 patients had received prior chemotherapy, with or without radiation. The principal acute toxicity was abdominal pain in 10 patients; this was usually accompanied by signs of peritoneal irritation and was always responsive to nonsteroidal antiinflammatory medications. The major toxicity was dose-related neutropenia; Grade 3 or 4 toxicity affected five of six patients at 800 mg/m2. Thrombocytopenia, nausea and vomiting, and alopecia were also observed. The recommended dose for further study is 700 mg/m2. The pharmacokinetics of etoposide in plasma and peritoneal fluid was measured in 19 patients. Peritoneal levels over the 4-h dwelling time declined monoexponentially with a harmonic mean half-life of 3.5 h (range, 1.9 to 7.8). Plasma levels rose to a peak at 2.9 +/- 1.7 (SD) h and then declined exponentially with a harmonic mean terminal half-life of 7.7 h (range, 4.2 to 15.6). The plasma area under the concentration-time curve increased linearly with respect to dose. The relative pharmacological advantage (ratio of peritoneal to plasma area under concentration-time curve) for i.p. administration was measured as 2.8 and was independent of dose. Based on the high plasma protein binding of etoposide (94%) and the minimal protein binding in the fluid instilled i.p., the ratio of the areas under the concentration-time curves of free drug is estimated to be 4%. These results illustrate that tumor confined to the peritoneal cavity would be exposed to substantially higher free (diffusible) drug concentrations following i.p. than following i.v. administration and support the further evaluation of etoposide by this route.
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PMID:Phase I pharmacokinetic study of intraperitoneal etoposide. 200 23

We report the results of a preclinical study comparing four different purging protocols using a promyelocytic human cell line HL-60 and myeloid leukemic progenitor cells (colony-forming unit-leukemic [CFU-L]) from acute myelogenous leukemia (AML) patients assayed in semisolid culture. We studied the antileukemic effect of (1) Single-cycle complement-mediated lysis by two different monoclonal antibodies (MoAbs) (M195 [CD33] and F23 [CD13] 40 micrograms/mL), reactive with distinct antigens found on early myeloid cells and monocytes, used alone and in combinations; (2) 4-Hydroperoxycyclophosphamide (4-HC) (80 mumol/L or 100 mumol/L) alone; or (3) combined with VP-16 (5 micrograms/mL) and (4) a cocktail of 1 through 3 as above (combined immunochemotherapy). More than 4 logs of HL-60 tumor cell elimination were observed after 1 hour of incubation with both MoAbs plus 4-HC + VP-16 while the single treatment (immunotherapy or chemotherapy) provided 1.5 and 3.5 logs of colony-forming inhibition, respectively. When the same protocols were tested on cryopreserved leukemic cells from eight patients with AML, we observed a mean value of CFU-L inhibition of 92.3% +/- 2.5% SD, 95.5% +/- 1.4% SD, and 99% +/- 0.8% SD after MoAbs and complement lysis, 4-HC, and 4-HC + VP-16 treatment, respectively. The combined treatment of MoAbs and 4-HC + VP-16 produced more than 3-log reduction of CFU-L colony formation. By comparison, the mean recovery of committed normal bone marrow progenitors after incubation with MoAbs and complement was 12% for CFU-granulocyte-macrophage (CFU-GM), 22.9% for burst-forming unit erythroid (BFU-E), and the recovery following 4-HC + VP-16 treatment was 4.4% for CFU-GM and 5.6% BFU-E. In subsequent experiments, highly purified CD34+ blast cells, enriched by positive selection, and stimulated in liquid culture by cytokines (interleukin-1 [IL-1], IL-3, and combination of both) or MO-conditioned medium (MoCM), demonstrated that immunochemotherapy spares hematopoietic colony-forming cells earlier than day 14 CFU-GM, in vitro.
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PMID:Autologous bone marrow transplantation in acute myelogenous leukemia: in vitro treatment with myeloid-specific monoclonal antibodies and drugs in combination. 201 6

It is generally difficult to treat patients with ovarian cancer. A Tenckhoff catheter was implanted in eighteen patients for intraperitoneal chemotherapy and drainage of ascites. Sixteen cases including 5 recurrent cases were treated with anticancer drug. It could not be used in two cases by bowel adhesion, so immediately catheters were removed. CDDP (100-150 mg/body) with or without Etoposide (180-300 mg/body) in 2 liters of saline was administered via Tenckhoff catheter over 30 minutes with a dwell time of 4 hours. We have studied the kinetics of CDDP and Etoposide in ascites and blood after intraperitoneal chemotherapy. High concentrations of free-CDDP and Etoposide were reached for 4 hours in the ascites but concentrations in the blood varied. These results showed obviously high values and direct effects on the tumor cells in the abdominal cavity and the peritoneal clearance depended on the severity of carcinomatous peritonitis in each case. Twelve cases showed decrease, but 4 cases increase of ascites. Five recurrent cases and one patient of stage IV died. Seven cases are outpatients and the disease free duration of their ranges are from 1 to 24 months. Three patients are now under treatment. Intraperitoneal chemotherapy elicited only mild nausea, myelosuppression and no significant changes of renal function. No patients had signs of catheter infection and peritonitis. These findings suggested that a Tenckhoff catheter was valuable to treat and manage ovarian cancer patients with little side effect.
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PMID:[The value of a Tenckhoff catheter in ovarian cancer]. 202 87


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