How camptothecin works?
How camptothecin works?
Camptothecin binds to the topoisomerase I and DNA complex resulting in a ternary complex, stabilizing it and preventing DNA re-ligation and therefore causes DNA damage which results in apoptosis.
How does camptothecin cause apoptosis?
Camptothecin caused apoptosis in SiHa cells by inducing mitochondrial membrane permeability changes that lead to the loss of mitochondrial membrane potential, decreased Bcl-2 levels, cytochrome c release, caspase-3 activation, formation of reactive oxygen species and depletion of GSH.
How is camptothecin produced?
It is commercially produced from plants, mainly Camptotheca acuminata and Nothapodytes nimmoniana2. Camptothecin is the third most in-demand alkaloid after taxol and vinca-alkaloids for anti-cancer applications, and inhibits DNA topoisomerase I in cancer cells leading to cell death3.
Is camptothecin hydrophobic?
(2) However, camptothecin is extremely hydrophobic due to the planar structure without hydrophilic moieties, and it is not in clinical use because of its water insolubility.
Is camptothecin cytotoxic?
Abstract. Camptothecin is a specific topoisomerase I poison and is highly cytotoxic to eukaryotic cells. In the present study, we show, using a pulse field gel electrophoresis assay, that camptothecin induces DNA double strand breaks (DSBs) specifically in newly replicated DNA.
How do you prepare camptothecin?
- Prepare a 1 mM stock solution of Camptothecin (Sigma Cat.
- Add 4-6 µM (final concentration) Camptothecin to cell suspension (eg, 5 x 10 5 cells/ml in tissue culture medium).
- Perform a time course to obtain optimum results; a 2-12 hr incubation at 37°C is suggested.
Is Topotecan a camptothecin?
Irinotecan and topotecan are two water soluble camptothecin derivatives already approved for use in neuroblastoma. Their mechanism of action is based on inhibition of topoisomerase I.
Where is camptothecin from?
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 traditional medicine.
How is camptothecin extracted?
Extraction of camptothecin The dried biomass (0.3 g) was dissolved in 20 ml of distilled water and homogenized using a mortar and pestle, followed by liquid – liquid extraction, repeated thrice using 50 ml of chloroform: methanol solvent mixture (4:1).
Is camptothecin water soluble?
Camptothecin (CPT, 1) is a plant alkaloid from the Camptotheca acuminata tree. In in vitro assay, camptothecin exhibited excellent topoisomerase I inhibitory activity but poor water solubility (2.5×10−3 mg ml−1) and unpredictable toxicity.
Is camptothecin used in clinic?
Currently, irinotecan and topotecan are the most widely used camptothecin analogs in clinical use and clinical trials are ongoing to better characterize their spectra of clinical activity, to determine their optimal schedules of administration and to define their use in combination with other chemotherapeutic agents.
Does hydrogen peroxide induced apoptosis?
Hydrogen peroxide is currently the most widely used apoptosis inducer due to its broad cytotoxic efficacy against nearly all cell types.
Who discovered camptothecin?
The research team of Monroe E. Wall, Mansukh C. Wani, and colleagues discovered two life-saving anticancer agents from natural products. In 1966, they reported the first of these, Camptothecin, from the Chinese tree Camptotheca acuminata.
Is camptothecin a prodrug?
Methotrexate–Camptothecin Prodrug Nanoassemblies as a Versatile Nanoplatform for Biomodal Imaging-Guided Self-Active Targeted and Synergistic Chemotherapy.
How do you dissolve camptothecin?
At higher concentrations, heating is required for the product to dissolve completely (approximately 10 minutes at 95 °C), but some precipitation occurs upon cooling to room temperature. It is also soluble in 1 N NaOH (50 mg/ml).
What is the mechanism of action of camptothecin?
Camptothecin (NSC-100880, CPT, Campathecin, (S)- (+)-Camptothecin) is a specific inhibitor of DNA topoisomerase I (Topo I) with IC50 of 0.68 μM in a cell-free assay. Camptothecin induces apoptosis in cancer cells via microRNA-125b-mediated mitochondrial pathways. Phase 2.
Is DNA topoisomerase I necessary for the cytotoxic effects of camptothecin?
Eng WK, Faucette L, Johnson RK, Sternglanz R. Evidence that DNA topoisomerase I is necessary for the cytotoxic effects of camptothecin. Mol Pharmacol. 1988;34:755–760.
What is the new highly lipophilic camptothecin BNP1350 used for?
New highly lipophilic camptothecin BNP1350 is an effective drug in experimental human cancer. Int J Cancer. 2000;88:260–266. [PubMed] [Google Scholar] 277. Matsui S, Endo W, Wrzosek C, Haridas K, Seetharamulu P, Hausheer FH, Rustum YM.
How do you use camptothecin to remove dye from urethane treated cells?
Cells are incubated with Camptothecin for 48 hours and then with fresh medium for 48 hours. Camptothecin at each concentration is added in quadruplicate. Following a 4-hour incubation of treated cells with MTT, the reduced dye product is extracted from the cells with 0.2 mL of DMSO followed by 50 μL of Sorensen’s buffer.