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)

It has previously been shown that B-859-35 ((-)-3-methyl-5- 3-(4,4-diphenyl-l-piperidinyl)-propyl-l,4-dihydro- 2,6-dimethyl-4-(3-nitrophenyl)-pyridine-3,5-dicarboxylate-hydrochloride) exerts a selective carcinostatic effect on some tumors. In order to evaluate whether the anti-cancer activity of B-859-35 can be modulated, we combined the new drug with several established anti-tumor drugs. A combination of B-859-35 with VP-16 (etoposide) in MDR(multi-drug-resistant-gene)-expressing Walker rat carcinoma cells shows synergism. A combination of B-859-35 with doxorubicin results in stronger synergism than verapamil/doxorubicin, especially at low concentrations of B-859-35. The resistance of mdrl(human multi-drug-resistance-gene)-expressing human HeLa KB-8-5 cells to doxorubicin can be reversed with non-toxic or weakly toxic concentrations of B-859-35 to the sensitivity of the parent KB-3-l cells. The finding that an anti-tumor drug is able to reverse multi-drug resistance makes B-859-35 an interesting drug for cancer treatment.
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PMID:B-859-35, a new drug with anti-tumor activity reverses multi-drug resistance. 184 22

Etoposide (VP-16) resistance is expressed following in vitro exposure of HN-1 and MCF-7 human tumor cells to the drug itself or to fractionated X irradiation. VP-16-selected sublines prove cross-resistant to Adriamycin, amsacrine and actinomycin D, whilst X-ray-pretreated sublines show cross-resistance to only actinomycin D. These differential responses, in the HN-1 series, are not associated with significant differences in amounts of immunoreactive topoisomerase (topo) II, altered topo-II catalytic activity of nuclear extracts or changes in susceptibility of the topo II to VP-16- or amsacrine-induced DNA-protein cross-link formation. Therefore significant modifications in topo II appear not to be implicated in VP-16 resistance in these HN-1 sublines.
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PMID:A lack of detectable modification of topoisomerase II activity in a series of human tumor cell lines expressing only low levels of etoposide resistance. 184 24

Investigations with the melphalan-resistant human rhabdomyosarcoma xenograft TE-671 MR were carried out to identify patterns of cross-resistance and collateral sensitivity and to define the mechanism(s) mediating melphalan resistance. TE-671 MR was cross-resistant to thio-TEPA, mitomycin, vincristine, and cisplatin, and partially resistant to chlorambucil and cyclophosphamide. TE-671 MR and the parent line TE-671 were both resistant to 1,3-bis(2-chloroethyl)-nitrosourea and expressed similar levels of O6-alkylguanine-DNA alkyltransferase. TE-671 MR retained full sensitivity to actinomycin D and demonstrated enhanced sensitivity to VP-16 compared to TE-671. Treatment of TE-671 MR with melphalan plus VP-16 resulted in greater than additive growth delays. The frequency of hypoxic regions was similar in TE-671 MR and TE-671, respectively. Measurement of tumor-to-plasma levels at 180 min following i.p. administration of melphalan at 0.5 of the 10% lethal dosage showed mean tumor-to-plasma ratios of 3.81 in TE-671 MR and 7.38 in TE-671, respectively. The lower drug levels in TE-671 MR may be contributing to the resistance to melphalan and thus indicate the need for further studies to define the reasons for these differences in tumor drug level.
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PMID:Therapeutic analysis of melphalan-resistant human rhabdomyosarcoma xenograft TE-671 MR. 185 7

Between September 1986 and December 1988, 125 patients with osteosarcoma of the extremities entered the second neoadjuvant study at the authors' institution. Patients received preoperatively two cycles of methotrexate (MTX) intravenously, followed by cisplatinum (CDP) intraarterially, plus adriamycin (ADM) intravenously. After surgery, the patients classified as "good responders" (more than 90% tumor necrosis) received ADM, MTX, and CDP, while the "poor responders" (less than 90% tumor necrosis) had a longer chemotherapy that included ifosfamide and etoposide (VP-16) in addition to MTX, ADM, and CDP. Limb salvage was possible in 85% of patients, 8% had an amputation, and 7% had a rotationplasty. The surgical margins were adequate (radical or wide) in 88% of cases and inadequate (marginal or intralesional) in 12%. At an average follow-up period of 28 months (range, 13 to 41), 109 patients (87%) remained continuously disease free, 15 (12%) relapsed with pulmonary metastases, and one patient (0.8%) had a local recurrence. Compared with the first neoadjuvant study at the authors' institution that used only MTX and CDP preoperatively, the percentage of limb salvages, "good responders," and continuously disease-free survival at two years was significantly higher in the second Rizzoli neoadjuvant study (85%, 74%, and 87% versus 77%, 52%, and 59%). Systemic toxicity because of chemotherapy was superimposable. A retrospective analysis of the real dose intensity for each patient demonstrated a correlation between the intensity of chemotherapy and prognosis.
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PMID:Neoadjuvant chemotherapy for nonmetastatic osteosarcoma of the extremities. 188 64

Anti-tumor effects of etoposide (VP-16), vincristine and mitomycin C were evaluated with four human neuroblastoma xenograft, according to Battelle Columbus Laboratories protocol. Etoposide is one of the agents which has been reported to be effective against advanced neuroblastoma clinically, if combined with other agents. While vincristine was effective against 1 out 4 neuroblastoma xenografts, TS-N-2, with 58.1% maximum inhibition rate, etoposide was assessed ineffective as a single agent in all of the 3 xenografts used. Since etoposide had no effect on the weight gain in nude mice in this xenograft experiment, the dose of etoposide was increased two-fold against 2 xenografts, but found ineffective also in the increased dose. Mitomycin C, which has not been used in childhood malignant tumors, was effective against 2 out of 4 xenografts, TNB-9 and SK-N-AS, with 72.0% and 78.4% maximum inhibition rates, respectively.
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PMID:[In vivo assessment on the therapeutic effects of etoposide, vincristine and mitomycin C against human neuroblastoma]. 190 21

Regional blood flow of brain tumors and normal brain tissue of rats before and during angiotensin II (AT II)-induced hypertension were measured using an electrolytic flowmeter and a laser flowmeter. Etoposide concentration in the tumor and brain tissue after intracarotid administration were also measured in brain tumor bearing rats with or without AT II-induced hypertension. A suspension of 5 x 10(5)/10 microliters 9L gliosarcoma cells was inoculated into the left caudate-putamen of CD Fischer 344 rats. Before induced hypertension, regional blood flow of the tumor (28.2 +/- 2.6 ml/100 g/min; mean +/- SEM) and the contralateral caudate-putamen (23.0 +/- 1.8 ml/100g/min) in the tumor bearing rats were significantly lower than that of the caudate-putamen (43.9 +/- 4.1 ml/100g/min) in the normal rats (p less than 0.01). Intravenous administration of AT II at a dose of 0.4-0.6 microgram/body/min increased the mean arterial blood pressure from 96.5 +/- 4.7 mmHg to 138.0 +/- 3.6 mmHg. AT II-induced hypertension resulted in an approximate 1.8(1.1 - 3.6)-fold increase in the regional tumor blood flow. On the other hand the regional blood flow of the contralateral caudate-putamen was slightly decreased at the rate of 6%. The mean concentration of etoposide with AT II-induced hypertension in the tumor tissue was 2.2-fold higher than that without AT II-induced hypertension. However, etoposide delivery to normal brain tissue was small. From these results, induced hypertension with intravenously administrated AT II selectively increase the tumor blood flow and drug delivery to brain tumor tissue. Intracarotid chemotherapy with AT II-induced hypertension might contribute to enhance therapeutic effect of malignant brain tumors.
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PMID:[Selective enhancement of tumor blood flow and drug delivery to brain tumors in experimental rat gliomas under angiotensin II-induced hypertension]. 191 Sep 50

We report herein, the histological observations taken at initial laparotomy from a 55 year old man with unresectable gastric cancer who responded almost completely to chemotherapy with Etoposide/Adriamycin/Cisplatin (EAP). The patient underwent a second operation after 2 cycles of EAP therapy and the stomach and adjacent lymph nodes were successfully resected. Histologic findings showed that cancer cells in the main tumor including the site of direct invasion had completely disappeared and been replaced by regenerated mucosa. The metastatic lymph node tumor was also partially killed, as indicated by a cluster of viable cancer cells which was divided by a strip of necrotic tissue. These findings led us to conclude that EAP therapy was remarkably effective for the patient.
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PMID:The effectiveness of a combination of etoposide/adriamycin/cisplatin (EAP) against inoperable gastric cancer--report of a histologically proven case. 196 Sep 1

Tyrosinase-dependent activation of hydroxybenzenes forms reactive compounds, including catechols and o-quinones, and some of which show antitumor activity against pigmented melanomas. Since VP-16 is a phenoxy-containing antitumor drug, forms free radicals and reactive o-quinones during peroxidative activation, we evaluated the cytotoxicity of VP-16 to both tyrosinase-containing and non-tyrosinase-containing tumor cells. Our results show that VP-16 is significantly more cytotoxic to B-16/F-10 melanoma cells than human MCF-7 breast tumor cells. Phenylthiocarbamide, an inhibitor of tyrosinase activity, selectively decreased VP-16 toxicity only in melanoma cells. Furthermore, VP-16 was readily activated to its phenoxy free radical intermediate by purified tyrosinase, indicating tyrosinase may play a role in VP-16 toxicity in pigmented melanomas.
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PMID:Tyrosinase-induced free radical formation from VP-16,213: relationship to cytotoxicity. 196 66

Chemoembolization using CDDP, VP-16 and lipiodol was carried out for 7 patients with hepatocellular carcinoma (HCC). CDDP/lipiodol, CDDP/VP-16, CDDP/lipiodol (lipiodol 2-10 ml, CDDP 1-2 mg/kg, VP-16 100 mg/body) and gelatine sponge were administered in that order through the catheter located in the proper, or right or left hepatic artery. Three patients underwent hepatic resection 38-50 days after this treatment. Complete necrosis of the tumor was recognized in the one case, although the portion of necrosis did not exceed 70% in large sized HCC as the diameter of more than 10 cm. In 4 unresectable cases the decreases in tumor size were observed by ultrasonography and computed tomography. The response was: 3 partial responses and 1 no change. One out of 4 cases could undergo hepatic resection 17 months after this treatment. Two patients are alive 20 months after this treatment, although one patient died of HCC after 25 months. Serious side effect was not observed.
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PMID:[Chemoembolization therapy with lipiodol, cisplatin and etoposide for hepatocellular carcinoma]. 196 31

Fifteen patients aged over 65 years of age with advanced non-small-cl lung cancer (mean age = 70.7, stage IIIb: IV = 4:11) were treated with combination chemotherapy consisting of Cisplatin (50 or 80 mg/m2) and a vinca-alkaloid (Vindesine 3 mg/m2 or Etoposide 80 mg/m2). The effectiveness and side effects of this cisplatin therapy in different combinations of vinca-alkaloid regimens (Vindesine vs Etoposide) were examined. The mean dose of Cisplatin in the Etoposide combination group (75.2 mg/m2) was significantly higher than that in the Vindesine combination group (54.3 mg/m2) (p less than 0.01). A notable reduction the tumor size was observed in 25% of the Etoposide group, only. The 6-month survival rate and one-year survival rate were respectively 85.7%, 57.1% in the Vindesine + Cisplatin group, and 87.5%, 50% in the Etoposide + Cisplatin group. The common side effects were nausea, vomiting, anorexia, and alopecia. These symptoms were either alleviated by antiemetic drugs or followed by spontaneous recovery. Leucopenia, anemia and thrombocytopenia were found in both groups, and there was no difference in the time course of myelosuppression between the two groups. The extent of nephrotoxicity was assessed by creatinine clearance rate. Its decrease in the Vindesine group (60.1----38.9 ml/min) was higher than that in the Etoposide group (64.9----48.9 ml/min), while there was no significant change in BUN, serum creatinine and urine NAG between the two groups. There were no cases in which chemotherapy schedules had to be interrupted due to myelosuppression and nephrotoxicity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Cisplatin and vinca alkaloid combination chemotherapy of advanced non-small-cell lung cancer in the aged]. 196 86


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