site stats

Camptothecin resistance

WebMay 13, 2015 · In continuation of our program aimed at the development of natural product-based pesticidal agents, three series of novel camptothecin derivatives were designed, synthesized, and evaluated for their biological activities against T. Cinnabarinus, B. brassicae, and B. xylophilus. All of the derivatives showed good-to-excellent activity … WebJan 1, 2013 · Camptothecin (CPT) is a water insoluble and cytotoxic monoterpene indole alkaloid, which is used as the substrate to form water-soluble derivatives (such as …

Camptothecin Sensitivity Is Mediated by the Pleiotropic Drug Resistance ...

WebJan 1, 2001 · The resistance ratio to CPT was >2000 fold. Western blot analysis using monoclonal antibody against top1 does not detect top1 in P388/CPT45. This cell line was used recently to show that the top1 inhibition might contribute to the antiproliferative activity of 1-β- d -arabinofuranosylcytosine (12). WebObjective: To determine the prognostic role of a K-ras mutation in tumor tissue of patients with refractory colon cancer who received irinotecan hydrochloride (CPT-11). Methods: DNA was extracted from paraffin-stored tumor tissue of 35 patients with progressive colon cancer failing treatment with 5-fluorouracil who subsequently received CPT-11 (100 mg/m2 i.v. … fixture \u0026 furnishing level翻译 https://wylieboatrentals.com

Use of Camptothecin-resistant Mammalian Cell Lines to Evaluate …

WebCamptothecin stabilizes a covalent enzyme-DNA intermediate that is converted into lethal double strand DNA lesions during S phase of the cell cycle. Yeast SCT1 mutants were … Studies have shown that substitution at position 7, 9, 10 and 11 can have positive effect on CPT activity and physical properties, e.g. potency and metabolic stability. Enlargement of the lactone ring by one CH 2 unit also enhances its abilities, as in homocamptothecin. Substitution at position 12 and 14 leads to inactive derivative. WebMar 31, 2016 · DNA topoisomerase I (Top1) is a DNA unwinding protein and the specific target of the camptothecin class of chemotherapeutic drugs. One of these, irinotecan, acting through its active metabolite SN-38, is used in the treatment of metastatic colorectal cancer. However, resistance to irinotecan represents a major clinical problem. Since … fixture \u0026 furnishing level

FL118, a novel camptothecin derivative, is insensitive to ABCG2 ...

Category:Mechanisms of Resistance to Camptothecins SpringerLink

Tags:Camptothecin resistance

Camptothecin resistance

Topoisomerase I inhibitors: camptothecins and beyond

WebOct 7, 2016 · The camptothecins are a new class of chemotherapeutic agents which have a novel mechanism of action targeting the nuclear enzyme topoisomerase I. Knowledge of the structure-activity relationships of the parent compound camptothecin has led to the development of effective soluble analogues with manageable toxicities. WebMay 6, 2008 · We found that CPT-producing plants, including Camptotheca acuminata, Ophiorrhiza pumila, and Ophiorrhiza liukiuensis, have Top1s with point mutations that confer resistance to CPT, suggesting the effect of an endogenous toxic metabolite on the evolution of the target cellular component.

Camptothecin resistance

Did you know?

WebSep 16, 2024 · This suggests that G363C and G737S mutations had only slight effects on CPT resistance. On the basis of these results, we set the concentration of CPT and Genz for further analysis as 10 μM... WebDec 1, 2024 · Camptothecin discovery and early development. Camptothecin (CPT) (Figure 1A) is a pentacyclic alkaloid that was first isolated from stem wood of Camptotheca acuminata by botanists working in the USDA’s Plant Introduction Division in the mid-1950s [].Camptotheca acuminata is a tree native to China and its bark is a recognized Chinese …

WebDec 31, 2013 · Camptothecin (CPT) is a kind of quinoline alkaloid that has gained great attention due to its unique anti-tumor activities . Two semi-synthetic water-soluble … WebApr 28, 2015 · Irinotecan is a camptothecin analogue currently used in clinical practice to treat advanced colorectal cancer. However, acquired resistance mediated by the drug efflux pump ABCG2 is a recognized problem. We reported on a novel camptothecin analogue, FL118, which shows anticancer activity superior to irinotecan.

WebSupported by detailed understanding of their mechanism of action, and facilitated by chemical manipulations that have amplified their solubility, the camptothecins have advanced to the forefront of several areas of therapeutic and developmental chemotherapy. Additive and synergistic laboratory interactions with other cytotoxic drugs have been … WebCamptothecins are broad-spectrum anticancer drugs that specifically target DNA topoisomerase I. Although the availability of camptothecins has had a significant impact on cancer therapeutics, de novo or acquired clinical resistance to camptothecins is common.

WebSep 11, 2007 · Camptothecin demonstrated strong anticancer activity in preliminary clinical trials but also low solubility and adverse drug reaction. Camptothecin is believed to be a …

WebBenedetti P, Fiorani P, Capuani L, Wang JC. 1993 Camptothecin resistance from a single mutation changing glycine 363 of human DNA topoisomerase I to cysteine. Cancer Res … canning town alcohol shopWebDec 5, 2024 · The highly toxic payloads, for instance, maytansine, camptothecin derivatives, auristatin, or doxorubicin are recommended to choose in the conjugates. 9 Finally, ... At the same time, the drug resistance, the recurrence and metastasis of cancer still seriously threaten the health of the patients. 34 Therefore, it is urgent to design highly ... canning town fireWebSep 15, 2000 · Several resistance mechanisms to camptothecin and its derivatives have been described, including mutations in topoisomerase I [1], decreased levels of topoisomerase I [2], and decreased topotecan accumulation in P-glycoprotein-overexpressing cells [3]. canning town efesWebcamptothecin-resistant. The catalytic and structural dy-namical properties of a human DNA topoisomerase I mutant in which Ala-653 in the linker domain was mu-tated into Pro have been investigated. The mutant is resistant to camptothecin and in the absence of the drug displays a cleavage-religation equilibrium strongly shifted toward religation. canning town banyafixture\u0027s 1wWebAug 1, 1998 · Recent Food and Drug Administration approval of the camptothecin analog irinotecan (CPT-11 [Camptosar]) for the treatment of colorectal cancer resistant to … canning town fcWebDec 16, 2024 · Camptothecin derivatives are precursors of potent anticancer agents, but their biosynthesis remains largely unknown. ... D. et al. Induction of multiple pleiotropic drug resistance genes in yeast ... fixture\u0027s by