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PubMed1988

Effects of VM26, a specific inhibitor of type II DNA topoisomerase, on SV40 chromatin replication in vitro.

We have examined the influence of VM26 (teniposide), a specific inhibitor of mammalian type II DNA topoisomerase, on the replication of SV40 minichromosomes in vitro. The replication system we used consists of replicative intermediate SV40 chromatin as substrate which is converted to mature SV40 chromatin in the presence of ATP, deoxynucleotides and a protein extract from uninfected cells. The addition of 100 microM VM26 to this system reduces DNA synthesis to 70 to 80 percent of the control and leads to an accumulation of 'late replicative intermediates'. The VM26 induced block of replication was not released by the addition of large quantities of type I DNA topoisomerase. We conclude, that type II DNA topoisomerase is essential for the final replication steps leading from late Cairns structures of replicative intermediates to monomeric minichromosomes. It appears that type I DNA topoisomerase can function as a swivelase during most of the replicative elongation phase, but must later be replaced by type II DNA topoisomerase.

Animals↗

PubMed1994

Weekly carboplatin and VM-26 for elderly patients with small-cell lung cancer.

BACKGROUND: Elderly patients are excluded from chemotherapy trials, even though they represent 25% of those with small cell lung cancer. An effective chemotherapy regimen with limited toxicity should be developed with the aim not only of increasing the survival of these patients, but also of improving their quality of life and their independence. PATIENTS AND METHODS: Twenty-four patients with a median age of 72 years and small-cell lung cancer (SCLC) were included in the trial. Chemotherapy consisted of a weekly intravenous regimen of Carboplatin 80 mg/m2 and Teniposide 80 mg/m2 administered on an outpatient basis. RESULTS: Eight patients had limited and 16 extensive disease. After a median of 12 chemotherapy courses (2-31) the overall response rate was 66.7% (95% Cl: 44.7-84.4), with 5 patients in complete and 11 in partial remission. The median overall survival was 33 weeks, with 4 patients alive at more than one year. Improvement of symptoms occurred in 86% of patients. Toxicity, mainly hematological, was moderate. CONCLUSIONS: Weekly Carboplatin and VM-26 is an effective and non-toxic regimen for elderly patients, leading to results similar to those obtained with a more intensive regimen in a younger age group.

Aged↗

PubMed1987

Failure of combination chemotherapy of advanced follicular (low-grade) non-Hodgkin's lymphoma.

Twenty-two patients with Stage III and IV follicular non-Hodgkin's lymphoma were treated for 8 months by a chemotherapy regimen alternating between two different four-drug combinations (doxorubicin, teniposide, cyclophosphamide, prednisone; vincristine, cyclophosphamide, CCNU, prednisone). The overall response rate (complete and partial remission) was 68%. The complete remission rate was 23%. Twenty patients are alive, 50% of them are free of disease progression (median follow-up 76 months). It is concluded that our chemotherapy regimen is not satisfactory and that new therapeutic approaches are needed.

Adult↗

PubMedDate not supplied

Intensive alternating drug pairs after remission induction for treatment of infants with acute lymphoblastic leukemia: A Pediatric Oncology Group Pilot Study.

PURPOSE: Infants with acute lymphoblastic leukemia (ALL) often enter remission; however, they have a high rate of relapse. To prevent relapse, infants' tolerance of and benefits from early intensive rotating drug pairs as part of therapy were studied. METHODS: After prednisone, vincristine, asparaginase, and daunorubicin induction, 12 intensive treatments (ABACABACABAC) were administered in 30 weeks: A, intermediate dose methotrexate (MTX) and intermediate dose mercaptopurine (MP); B, cytosine arabinoside (Ara-C) and daunorubicin (DNR); C, Ara-C and teniposide (VM-26). Triple intrathecal chemotherapy (Ara-C, MTX, and hydrocortisone) was administered for central nervous system prophylaxis. Continuation therapy consisted of weekly MTX and daily MP for a total of 130 weeks of continuous complete remission. RESULTS: Thirty-three infants (1 year old or younger) with newly diagnosed ALL were treated. Two infants did not respond to induction, 1 died from sepsis during continuation, 1 received a bone marrow transplant, and 24 relapsed. Median time to relapse was 39 weeks. The event-free survival rate at 5 years was 17% (standard error +/- 7.7%). The most significant toxicities occurred during intensification and included fever-neutropenia and bacterial sepsis. CONCLUSION: Although early intensive rotating therapy is tolerable, the relapse-free survival rate remains poor for infants treated with the schedule on this protocol.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1994

Different modes of cell-killing action between DNA topoisomerase I and II inhibitors revealed by kinetic analysis.

We compared the modes of cell-killing by DNA topoisomerase I and II inhibitors. The effects of camptothecin (CPT), KT-6528 and UCE6 upon colony formation by inhibiting DNA topoisomerase I, and of etoposide (VP-16), teniposide, amsacrine and UCT4-A as inhibitors of DNA topoisomerase II were analyzed based upon a kinetic method that distinguishes between cell cycle phase-specific and -nonspecific agents. Human colorectal cancer WiDr cells were exposed to several concentrations of each agent for various periods and 90%-inhibitory concentrations (IC90) at each time were determined by means of a clonogenic assay. When exposure times and corresponding IC90s were plotted on a log-log scale, all inhibitors of DNA topoisomerase II gave curves including a linear portion with a slope of -1, which is characteristic of cell cycle phase-nonspecific agents. In contrast, the curves for all inhibitors of DNA topoisomerase I had a much steeper slope than -1, which is typical of cell cycle phase-specific agents. In agreement with this finding, the cells were remarkably accumulated in the G2-M phase when exposed to VP-16, but in late S-phase when exposed to CPT as determined by a flow cytometric assay. These results indicated that the two classes of agents kill cells in a quite different manner although they are inhibitors of similar enzymes.

Amsacrine↗

PubMed1995

Biomodulation by hyperthermia of topoisomerase II-targeting drugs in human colorectal cancer cells.

We examined whether heat stress could enhance the sensitivity of human colon cancer WiDr cells to topoisomerase II-targeting anticancer agents, etoposide (VP-16) and teniposide (VM-26), and also determined the most effective timing for the drug administration after exposure to hyperthermia. Both topoisomerase II contents and topoisomerase II activity were significantly increased in WiDr cells 3 to 12 h after heat stress at 43 degrees C for 1 h, in comparison with those immediately after the heat stress. Cytotoxicity by VP-16 was most significantly enhanced 3 to 12 h after exposure to 43 degrees C for 1 h, but no synergistic effect was observed when the drug was administered immediately after the heat stress. A combination of VM-26 with heat stress, but not that of a topoisomerase I-targeting camptothecin derivative (CPT-11), or vincristine, showed a synergistic cytotoxic effect on WiDr cells. VP-16 alone induced cellular accumulation at the G2 + M phase, whereas the combination of VP-16 and heat stress further increased the cell population at the G2 + M phase, and decreased S-phase cells. A possible application of the combination of VP-16 and hyperthermia in clinical use is discussed.

Adenocarcinoma↗

PubMed1985

Drug induced red blood cell autoantibodies co-developed with drug specific antibodies causing haemolytic anaemias.

Four individuals with anti-glafenine, anti-latamoxef and anti-teniposide antibodies were found to have an associated red blood cell autoantibody. The two components could be separated by selective absorption and showed distinct time course patterns. In three patients a well-defined blood group antigen was recognized as the receptor for both auto- and drug specific antibodies. Similarities between this type of immune response to drugs and the well-known hapten and carrier specificities developed in animals immunized by hapten-carrier conjugates are discussed.

Aged↗

PubMed1992

Failure of intensive chemotherapy in poor prognosis non-Hodgkin's lymphoma.

In an attempt to improve response and survival rates in patients with non-Hodgkin's lymphoma, a relatively intense six drug regimen MATCOP was developed comprising four-weekly cycles of methotrexate (100 mg/m2, IV, day 8), Adriamycin (30 mg/m2, IV, days 1,2), teniposide (75 mg/m2, IV, day 1), cyclophosphamide (300 mg/m2, po, days one to five), Oncovin (1.4 mg/m2, IV: maximum 2 mg, days 8, 15) and prednisolone (100 mg, po, days one to five). A randomised trial was conducted comparing MATCOP with the standard CHOP regimen, comprising three-weekly cycles of cyclophosphamide (750 mg/m2, IV, day 1), Adriamycin (50 mg/m2, IV, day 1), Oncovin (1.4 mg/m2 IV: maximum 2 mg, day 1) and prednisolone (100 mg, po, days two to six). Eighty patients with large cell lymphoma, diffuse mixed small cleaved and large cell lymphoma or diffuse small cleaved cell lymphoma were randomised, 47 to MATCOP and 33 to CHOP. MATCOP patients experienced increased granulocytopenia, thrombocytopenia (p less than 0.0001), mucositis (p = 0.002) and infections (p = 0.01) compared to CHOP patients. Complete response rates were similar: 66% for MATCOP patients and 61% for CHOP patients. There were no apparent differences in the time to relapse for patients achieving CR, the time to treatment failure or the overall survival time. Thus despite an increase in toxicity, the more intense regimen MATCOP failed to confer any therapeutic benefit compared with the standard CHOP regimen. Survival was not influenced but toxicity was increased by dose intensification.

Adolescent↗

PubMed2006

Results of the PETHEMA ALL-96 trial in elderly patients with Philadelphia chromosome-negative acute lymphoblastic leukemia.

BACKGROUND AND AIM: Only 20-30% of elderly patients with acute lymphoblastic leukemia (ALL) are enrolled in clinical trials because of co-morbid disorders or poor performance status. We present the results of treatment of Philadelphia chromosome-negative (Ph-) ALL patients over 55 yr treated in the PETHEMA ALL-96 trial. PATIENTS AND METHODS: From 1996 to 2006, 33 patients > or = 55 yr with Ph- ALL were included. Induction therapy was vincristine, daunorubicin, prednisone, asparaginase, and cyclophosphamide over 5 weeks. Central nervous system (CNS) prophylaxis involved triple intrathecal (IT) therapy, 14 doses over the first year. Consolidation-1 included mercaptopurine, methotrexate, teniposide and cytarabine, followed by one consolidation-2 cycle similar to the induction cycle. Maintenance consisted of mercaptopurine and methotrexate up to 2 yr in complete remission (CR) with monthly reinduction cycles (vincristine, prednisone and asparaginase) during the first year. RESULTS: Median (range) age was 65 yr (56-77). Phenotype (30 patients): early-pre-B 7, common/pre-B 18, T 5. Cytogenetics (28 patients): normal 12, complex 10, t(4;11) 2 and other 4. CR was achieved in 19/33 (57.6%) patients, early death occurred in 12 (36.4%) and 2 (6%) were resistant. Overall survival and disease-free survival probabilities (2 yr, 95% CI) were 39% (21%-57%) and 46% (22%-70%), respectively (median follow up of 24 months). Removal of asparaginase and cyclophosphamide from the induction decreased induction death (OR 0.119, CI 95% 0.022-0.637, P = 0.013) and increased survival (20% vs. 52%, P = 0.05). CONCLUSIONS: The prognosis of elderly Ph- ALL patients is poor. In this study, less intensive induction decreased toxic death, allowing delivery of planned consolidation therapy and increased survival probability.

Aged↗

PubMed1991

Familial hemophagocytic lymphohistiocytosis. Clinical review based on the findings in seven children.

Clinical, laboratory, and histological findings in FHL of diagnostic importance were intermittent fever, hepatosplenomegaly, peripheral blood cytopenia, hypertriglyceridemia, hypofibrinogenemia, and a lymphohistiocytic accumulation with hemophagocytosis in the mononuclear phagocytic system. Fine-needle aspiration biopsy from the spleen appeared to be a useful method for revealing hemophagocytosis. The treatment of induction and relapses, as well as the maintenance therapy, included administration of teniposide, etoposide, and corticosteroids. The regimen had to be individualized for each child since the clinical course was highly variable. Half of the children given successful induction therapy (3/6) are still alive with over a 3-year survival after diagnosis.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1997

Relationship between lethal effects and topoisomerase II-mediated double-stranded DNA breaks produced by anthracyclines with different sequence specificity.

The role of the site selectivity of topoisomerase II poisoning in the cytotoxic activity of anthracyclines has not been established. In this article, we have thus studied the levels and persistence of double-stranded DNA breaks (DSB) along with the cytotoxic activity in human leukemic HL60 cells of seven anthracyclines, including doxorubicin, daunorubicin, and idarubicin, as well as sugar-modified analogues characterized by an altered sequence specificity. Epimerization at the 3' position of the sugar moiety markedly affected the biological activity; indeed, a dramatic reduction of drug effects was evident for 3'-deamino-3'-epi-hydroxy-4'-deoxy-4'-amino-daunorubicin. The studied analogues could be gathered into three groups based on the DSB/cytotoxicity ratio. At equitoxic concentrations: (a) parent drugs and 3'-deamino-3'-epi-hydroxy-4'-deoxy-4'-amino-daunorubicin endowed with the same sequence specificity stimulated low DSB levels; (b) 3'-epi-daunorubicin and 3'-deamino-4'-deoxy-4'-epi-amino-idarubicin, which have a different sequence specificity, and teniposide (a structurally unrelated poison) stimulated higher amounts of DSB; and (c) 4-demethoxy-3'-deamino-3'-hydroxy-4'-epi-doxorubicin stimulated the highest DSB levels. For the last agent, a faster rate of cleavage resealing, which is consistent with a reduced DNA binding affinity, could account for the increased DSB/cytotoxicity ratio compared with parent drugs. However, for other analogues, the observed differences in DSB persistence/resealing could not completely explain the different DSB/cytotoxicity ratios. The results thus suggest that the cytotoxic potency of anthracyclines may be the result of an interplay of the level, the persistence, and the genomic localization of topoisomerase II-mediated DNA cleavage.

Antibiotics, Antineoplastic↗

PubMed2004

A mutation in Escherichia coli DNA gyrase conferring quinolone resistance results in sensitivity to drugs targeting eukaryotic topoisomerase II.

Fluoroquinolones are broad-spectrum antimicrobial agents that target type II topoisomerases. Many fluoroquinolones are highly specific for bacterial type II topoisomerases and act against both DNA gyrase and topoisomerase IV. In Escherichia coli, mutations causing quinolone resistance are often found in the gene that encodes the A subunit of DNA gyrase. One common site for resistance-conferring mutations alters Ser83, and mutations to Leu or Trp result in high levels of resistance to fluoroquinolones. In the present study we demonstrate that the mutation of Ser83 to Trp in DNA gyrase (Gyr(S83W)) also results in sensitivity to agents that are potent inhibitors of eukaryotic topoisomerase II but that are normally inactive against prokaryotic enzymes. Epipodophyllotoxins, such as etoposide, teniposide and amino-azatoxin, inhibited the DNA supercoiling activity of Gyr(S83W), and the enzyme caused elevated levels of DNA cleavage in the presence of these agents. The DNA sequence preference for Gyr(S83W)-induced cleavage sites in the presence of etoposide was similar to that seen with eukaryotic type II topoisomerases. Introduction of the Gyr(S83W) mutation in E. coli strain RFM443-242 by site-directed mutagenesis sensitized it to epipodophyllotoxins and amino-azatoxin. Our results demonstrate that sensitivity to agents that target topoisomerase II is conserved between prokaryotic and eukaryotic enzymes, suggesting that drug interaction domains are also well conserved and likely occur in domains important for the biochemical activities of the enzymes.

Anti-Bacterial Agents↗

PubMed1990

Inhibition of topoisomerase II does not inhibit transcription of RNA polymerase I and II genes.

Injection of VM-26 (teniposide) into Xenopus oocytes inhibits the activity of topoisomerase II but does not inhibit transcription by RNA polymerases I and II. A specific assay for topoisomerase II, resolution of catenated DNA molecules into product rings, was used to quantitate VM-26 inhibition in vivo. When catenanes were injected without VM-26, about 60% of them were separated into product rings in the first 5 min after injection, and decatenation of the remainder was complete within 15 min. When VM-26 was coinjected, 60% of the catenanes were separated into product rings in the first 5 min after injection, but the remaining 40% were stable over the next 40 min. At 1 h after injection catenanes were no longer detected in the gel analysis, but the increasing numbers of linear product rings indicated that topoisomerase II continued to be inhibited by VM-26. These results suggest that a short lag of approximately 5 min is required for VM-26 to inhibit topoisomerase II and that after this initial period topoisomerase II is inhibited by more than 90%. There was no detectable decrease in transcription of injected rRNA and thymidine kinase (TK) genes or in the activity of the rRNA enhancer when these transcription templates were coinjected with VM-26. The time required for assembly of injected DNA into chromatin doubled in the presence of VM-26.

Animals↗

PubMed1986

In vivo localization of DNA topoisomerase II cleavage sites on Drosophila heat shock chromatin.

Similar to its inhibitory effect on mammalian DNA topoisomerase II, the cytotoxic drug VM26 (teniposide) also interferes with the breakage-reunion reaction of Drosophila melanogaster DNA topoisomerase II. VM26 induces topoisomerase II-mediated DNA breakage in vitro and in cultured D. melanogaster cells presumably by stabilizing an enzyme-DNA cleavable complex. The drug-induced DNA breaks on D. melanogaster hsp70 genes were mapped in cultured cells using the indirect end-labeling procedure. Multiple and specific cleavage sites occurred at both the 3' and 5' ends of the hsp70 genes. A number of these cellular topoisomerase II cleavage sites mapped close to the DNase I-hypersensitive regions of the hsp70 genes. The intensities of several topoisomerase II cleavage sites changed significantly on heat shock induction. Treatment of cultured D. melanogaster cells with VM26 at 25 degrees C resulted in the stimulation of transcription of the hsp70 genes. These results suggest that inhibition of DNA topoisomerase II may lead to heat shock transcription.

Animals↗

PubMed1992

P-glycoprotein but not topoisomerase II and glutathione-S-transferase-pi accounts for enhanced intracellular drug-resistance in LoVo MDR human cell lines.

The biochemical bases of the multidrug-resistant (MDR) phenotype were investigated in drug-resistant sublines derived from LoVo human colon carcinoma cell lines by doxorubicin (DOX) and teniposide (VM26) selection. In addition to P-glycoprotein-mediated drug extrusion through the plasma-membrane, LoVo MDR cells display a further drug-resistance mechanism. That is, to achieve equitoxic effects, LoVo MDR sublines require much higher intracellular drug concentrations than those required by LoVo drug-sensitive parent cell line. Involvement of mdr1, topoisomerase II and glutathione-S-transferase-pi (GST-pi) drug-resistance systems in intracellular drug resistance was investigated. Pharmacologic and biochemical data indicated that intracellular drug resistance in LoVo MDR sublines is uniquely consequent to the drug-transporting property of intracytoplasmic membrane-bound P-glycoprotein molecules which compartment drugs in vacuole-like structures.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2006

Standard chemotherapy with interferon compared with CHOP followed by high-dose therapy with autologous stem cell transplantation in untreated patients with advanced follicular lymphoma: the GELF-94 randomized study from the Groupe d'Etude des Lymphomes de l'Adulte (GELA).

The purpose of this study is to compare our standard chemotherapy regimen (CHVP [cyclophosphamide, doxorubicin, teniposide, and prednisone]) plus interferon with 4 courses of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) followed by high-dose therapy with autologous stem cell transplantation (ASCT) in treatment-naive patients with advanced follicular lymphoma. Four hundred one patients were included from July 1994 to March 2001: 209 received 12 cycles of CHVP plus interferon alpha for 18 months (CHVP-I arm) and 192 received 4 cycles of CHOP followed by high-dose therapy (HDT) with total body irradiation and ASCT (CHOP-HDT arm). Overall response rates were similar in both groups (79% and 78% after induction chemotherapy, respectively). One hundred thirty-one of the 150 patients eligible for HDT underwent transplantation (87%). Intent-to-treat analysis after a median follow-up of 7.5 years showed that there was no difference between the 2 arms for overall survival (P = .53) or event-free survival (P = .11). Patients with a complete response at the end of the induction therapy had a statistically longer event-free survival and overall survival (P = .02 and < .001, respectively). After long-term follow-up, our study showed that there was no statistically significant benefit in favor of first-line high-dose therapy in patients with follicular lymphoma. High-dose therapy should be reserved for relapsing patients.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2006

Body mass index does not influence pharmacokinetics or outcome of treatment in children with acute lymphoblastic leukemia.

There is conflicting information about the influence of body mass index (BMI) on the pharmacokinetics, toxicity, and outcome of chemotherapy. We compared pharmacokinetics, outcome, and toxicity data across 4 BMI groups (underweight, BMI < or = 10th percentile; normal; at risk of overweight, BMI > or = 85th and < 95th percentile; overweight, BMI > or = 95th percentile) in 621 children with acute lymphoblastic leukemia (ALL) treated on 4 consecutive St Jude Total Therapy studies. Chemotherapy doses were not adjusted to ideal BMI. Estimates of overall survival (86.1% +/- 3.4%, 86.0% +/- 1.7%, 85.9% +/- 4.3%, and 78.2% +/- 5.5%, respectively; P = .533), event-free survival (76.2% +/- 4.2%, 78.7% +/- 2.1%, 73.4% +/- 5.5%, and 72.7% +/- 5.9%, respectively; P = .722), and cumulative incidence of relapse (16.0% +/- 3.7%, 14.4% +/- 1.8%, 20.6% +/- 5.1%, and 16.7% +/- 5.1%, respectively; P = .862) did not differ across the 4 groups. In addition, the intracellular levels of thioguanine nucleotides and methotrexate polyglutamates did not differ between the 4 BMI groups (P = .73 and P = .74, respectively). The 4 groups also did not differ in the overall incidence of grade 3 or 4 toxicity during the induction or postinduction periods. Further, the systemic clearance of methotrexate, teniposide, etoposide, and cytarabine did not differ with BMI (P > .3). We conclude that BMI does not affect the outcome or toxicity of chemotherapy in this patient population with ALL.

Adolescent↗

PubMed1986

Intensive and sequential combination chemotherapy for aggressive malignant lymphomas (protocol LNH-80).

Ninety-seven patients with aggressive malignant lymphoma (ML) were treated with an intensive and sequential chemotherapy (protocol LNH-80). There were 42 patients with intermediate grade ML, 53 patients with high-grade ML, and two patients with true histiocytic ML. Most of the patients were in advanced stage: 21 stage III and 61 stage IV. The LNH-80 protocol schedule comprised three phases: (1) induction with three courses of an intensified CHOP-Bleo (cyclophosphamide, doxorubicin, vindesine, methylprednisolone, and bleomycin); (2) consolidation with cytarabine, followed by high-dose methotrexate and folinic acid rescue, then asparaginase; and (3) final intensification with two courses of CVAP-Bleo (cyclophosphamide, teniposide, cytarabine, methylprednisolone, and bleomycin). CNS prophylaxis included one injection of methotrexate during each induction course and the drugs of the consolidation phase. In cases of initial CNS localization, cranial radiotherapy was added. Eighty-four patients (87%) went into complete remission (CR), 18 (21%) of whom relapsed, usually during the phase of treatment or within 6 months of completing chemotherapy. Sixty-three patients are alive with an overall median follow-up of 24 months. The median survival time and the median disease-free survival have not been reached, and the survival curve seems to have plateaued at above 60%. There was no statistical difference between intermediate-grade ML (CR 90%, relapse 18%) and high-grade ML (CR 84%, relapse 24%). The toxicity of this treatment is mainly encountered during the induction phase: almost all patients had short-term neutropenia, less than 0.500 g/L in 57, with a documented infection in 25. Overall treatment-related mortality was 6%, with four patients dying during the induction phase.

Adolescent↗