Search results for "topotecan"
showing 10 items of 18 documents
Investigation of Isoindolo[2,1-a] quinoxaline-6-imines as Topoisomerase I Inhibitors with Molecular Modeling Methods
2017
Background: Isoindolo[2,1-alpha] quinoxalines constitute an important class of compounds which demonstrated potent antiproliferative activity against different human tumor cell lines and topoisomerase I inhibitors. In particular, their water soluble imine or iminium salts recently synthesized showed potent growth inhibitory effect on NCI-60 tumor cell line panel and biological studies performed on the most active compounds demonstrated that they cause DNA damage via topoisomerase I poisoning. Objective: Herein, we investigate with molecular modeling methods, the common features responsible for topoisomerase I inhibition of the water-soluble isoindolo[2,1-alpha] quinoxalin-6-imines, by compa…
Structure-Activity Relationships of Cytotoxic Lactones as Inhibitors and Mechanisms of Action.
2020
Background: Some lactones prevent protein Myb-dependent gene expression. Objective: The object is to calculate inhibitors of Myb-brought genetic manifestation. Methods: Linear quantitative structure–potency relations result expanded, among sesquiterpene lactones of a variety of macrocycles (pseudoguaianolides, guaianolides, eudesmanolides and germacranolides), to establish which part of the molecule constitutes their pharmacophore, and predict their inhibitory potency on Myb-reliant genetic manifestation, which may result helpful as leads for antileukaemic therapies with a new mechanism of action. Results: Several count indices are connected with structure–activity. The α-methylene-γ-lacto…
Sorafenib plus topotecan versus placebo plus topotecan for platinum-resistant ovarian cancer (TRIAS): a multicentre, randomised, double-blind, placeb…
2018
Summary Background Antiangiogenic therapy has known activity in ovarian cancer. The investigator-initiated randomised phase 2 TRIAS trial assessed the multi-kinase inhibitor sorafenib combined with topotecan and continued as maintenance therapy for platinum-resistant or platinum-refractory ovarian cancer. Methods We did a multicentre, double-blind, placebo-controlled, randomised, phase 2 trial at 20 sites in Germany. Patients (≥18 years) with platinum-resistant ovarian cancer previously treated with two or fewer chemotherapy lines for recurrent disease were stratified (first vs later relapse) in block sizes of four and randomly assigned (1:1) using a web-generated response system to topotec…
Topoisomerase 1 inhibition suppresses inflammatory genes and protects from death by inflammation
2015
Unwinding DNA and unleasing inflammation Fighting infections often comes with collateral damage, which sometimes can be deadly. For instance, in septic shock, the overwhelming release of inflammatory mediators drives multi-organ failure. Rialdi et al. now report a potential new therapeutic target for controlling excessive inflammation: the DNA unwinding enzyme topoisomerase I (Top1) (see the Perspective by Pope and Medzhitov). Upon infection, Top1 specifically localizes to the promoters of pathogen-induced genes and promotes their transcription by helping to recruit RNA polymerase II. Pharmacological inhibition of Top1 in a therapeutic setting increased survival in several mouse models of s…
Topotecan plus ifosfamide in patients with platinum refractory advanced/metastatic non-small cell lung cancer: A phase II trial
2005
A number of second line treatments have been proposed in patients with advanced pretreated non-small cell lung cancer (NSCLC). However, either single agents or two or three drug combinations achieved very poor results with no superiority of any combination over monotherapy. We have treated 42 patients (30 males) affected by advanced/metastatic NSCLC progressing during front line cisplatin-based chemotherapy with a combination of topotecan (1.2 mg/m2) plus ifosfamide (1200 mg/m2) for 3 consecutive days every 3 weeks. The median age was 63 years (range 43-76); cell types were: squamous carcinoma (n=17), adenocarcinoma (n=16), large cell carcinoma (n=3), broncho-alveolar carcinoma (n=2) and un…
A phase II study of pegylated liposomal doxorubicin oxaliplatin and cyclophosphamide as second-line treatment in relapsed ovarian carcinoma
2006
We carried out a phase II nonrandomized study to examine the level of activity of oxaliplatin, pegylated liposomal doxorubicin, and cyclophosphamide in a patient population with relapsed ovarian cancer pretreated with platinum derivatives and paclitaxel. Patients received oxaliplatin (85 mg/m2), pegylated liposomal doxorubicin (30 mg/m2), and cyclophosphamide (750 mg/m2). A total of 49 patients (39 assessable for toxicity and response) were enrolled in this trial. Neutropenia grade 3 was observed in six patients (15%) and anemia grade 3 in one patient (0.2%). Fatigue grade 1–2 occurred in 26 patients (66%), nausea/vomiting grade 1 in 23 patients (58%), and alopecia grade 1–2 in 19 patients …
Sodium phenylbutyrate induces apoptosis in human retinoblastoma Y79 cells: The effect of combined treatment with the topoisomerase I-inhibitor topote…
2001
Our results demonstrate that sodium phenylbutyrate, a compound with a low degree of toxicity, exerted a cytotoxic effect on human retinoblastoma Y79 cells in a time- and dose-dependent manner. Treatment of Y79 cells for 72 h with phenylbutyrate reduced cell viability by 63% at 2 mM and 90% at 4 mM. Cell death caused by phenylbutyrate exhibited the typical features of apoptosis, as shown by light and fluorescent microscopy. Western blot analysis demonstrated that exposure of Y79 cells to phenylbutyrate decreased the level of the antiapoptotic factor Bcl-2 and induced the activation of caspase-3, a key enzyme in the execution phase of apoptosis. Moreover, treatment with phenylbutyrate markedl…
Topotecan-triggered degradation of topoisomerase I is p53-dependent and impacts cell survival.
2005
Abstract The anticancer drug topotecan belongs to the group of topoisomerase I (topo I) inhibitors. In the presence of topotecan, topo I cleaves the DNA but is unable to religate the single-strand break. This leads to stabilization of topo I-DNA–bound complexes and the accumulation of DNA strand breaks that may interfere with DNA replication. The molecular mechanism of controlling the repair of topo I-DNA covalent complexes and its impact on sensitivity of cells to topotecan is largely unknown. Here, we used mouse embryonic fibroblasts expressing wild-type p53 and deficient in p53, in order to elucidate the role of p53 in topotecan-induced cell death. We show that p53-deficient mouse embryo…
Loading profile of topotecan into polyvinyl alcohol microspheres (DC Bead™) over a 7-day period
2011
Purpose: DC Bead™ is successfully used for chemoembolization of various liver cancers. The purpose of this study was todetermine the loading capacity of the semi-synthetic topoisomerase-1 inhibitor topotecan into the DC Bead™ microspheres under static or agitated conditions and to assess the physicochemical stability over a period of 7 days. Methods: Commercially available topotecan hydrochloride powder (Hycamtin®) was reconstituted with water for injection to yield a nominal concentration of 1 mg/mL topotecan. Polyvinyl alcohol (PVA)-based microspheres (DC Bead™, 300–500 µm, 2 mL/vial) were mixed with 4 mL of the reconstituted topotecan solution. Vials were stored light protected at room …
Final results of OV16, a phase III randomized study of sequential cisplatin-topotecan and carboplatin-paclitaxel (CP) versus CP in first-line chemoth…
2013
5502 Background: Topotecan was evaluated in a novel combination regimen in comparison to standard therapy in front-line EOC. Methods: Women with newly diagnosed advanced EOC stages IIB-IV, ECOG performance status (PS) 0-1, age < 75, were randomized to either Arm 1: cycles 1 - 4: cisplatin 50 mg/m2 d1 plus topotecan 0.75 mg/m2 d1-5 IV; cycles 5 - 8: paclitaxel 175 mg/m2over 3 hrs d1 followed by carboplatin AUC5 day 1 or Arm 2: paclitaxel plus carboplatin as in Arm 1 for 8 cycles. The primary endpoint was progression free survival (PFS) and secondary endpoints included objective response, overall survival (OS), adverse event (AE) and Quality of Life (QoL). The sample size required 800 pts…