4750 Etoposide A semisynthetic derivative of podophyllotoxin that exhibits antitumor activity. Etoposide inhibits DNA synthesis by forming a complex with topoisomerase II and DNA. This complex induces breaks in double stranded DNA and prevents repair by topoisomerase II binding. Accumulated breaks in DNA prevent entry into the mitotic phase of cell division, and lead to cell death. Etoposide acts primarily in the G2 and S phases of the cell cycle. 33419-42-0 36462 C29H32O13 White powder. 236 - 251°C 9.78e-01 g/L Absorbed well, time to peak plasma concentration is 1-1.5 hrs. Mean bioavailability is 50% (range of 25% - 75%). Cmax and AUC values for orally administered etoposide capsules display intra- and inter-subject variability. There is no evidence of first-pass effect for etoposide. Etoposide inhibits DNA topoisomerase II, thereby inhibiting DNA re-ligation. This causes critical errors in DNA synthesis at the premitotic stage of cell division and can lead to apoptosis of the cancer cell. Etoposide is cell cycle dependent and phase specific, affecting mainly the S and G2 phases of cell division. Inhibition of the topoisomerase II alpha isoform results in the anti-tumour activity of etoposide. The drug is also capable of inhibiting the beta isoform but inhibition of this target is not associated with the anti-tumour activity. It is instead associated with the carcinogenic effect. Primarily hepatic (through O-demethylation via the CYP450 3A4 isoenzyme pathway) with 40% excreted unchanged in the urine. Etoposide also undergoes glutathione and glucuronide conjugation which are catalyzed by GSTT1/GSTP1 and UGT1A1, respectively. Prostaglandin synthases are also responsible for the conversion of etoposide to O-demethylated metabolites (quinone). Route of Elimination: Etoposide is cleared by both renal and nonrenal processes, i.e., metabolism and biliary excretion. Glucuronide and/or sulfate conjugates of etoposide are also excreted in human urine. Biliary excretion of unchanged drug and/or metabolites is an important route of etoposide elimination as fecal recovery of radioactivity is 44% of the intravenous dose. 56% of the dose was in the urine, 45% of which was excreted as etoposide. Half Life: 4-11 hours 1, carcinogenic to humans. (L135) For use in combination with other chemotherapeutic agents in the treatment of refractory testicular tumors and as first line treatment in patients with small cell lung cancer. Also used to treat other malignancies such as lymphoma, non-lymphocytic leukemia, and glioblastoma multiforme. Side effects include alopecia, constipation, diarrhea, nausea and vomiting and secondary malignancies (leukemia). 2014-09-11T02:05:21Z 2026-03-31T17:50:04Z http://en.wikipedia.org/wiki/Etoposide C01576 4911 DB00773 EVP true [H][C@]12COC(=O)[C@]1([H])[C@H](C1=CC(OC)=C(O)C(OC)=C1)C1=CC3=C(OCO3)C=C1[C@H]2O[C@@H]1O[C@]2([H])CO[C@@H](C)O[C@@]2([H])[C@H](O)[C@H]1O C29H32O13 InChI=1S/C29H32O13/c1-11-36-9-20-27(40-11)24(31)25(32)29(41-20)42-26-14-7-17-16(38-10-39-17)6-13(14)21(22-15(26)8-37-28(22)33)12-4-18(34-2)23(30)19(5-12)35-3/h4-7,11,15,20-22,24-27,29-32H,8-10H2,1-3H3/t11-,15+,20-,21-,22+,24-,25-,26-,27-,29+/m1/s1 VJJPUSNTGOMMGY-MRVIYFEKSA-N 588.5566 588.18429111 Exogenous Solid 0.6 HMDB14911 CHEMBL44657 33510 <p><a href="http://www.drugsyn.org/Etoposide.htm">DrugSyn.org</a></p> CHEM003653 DTXSID5023035 NS00009585 (10R,11R,15R,16S)-16-{[(2R,4aR,6R,7R,8R,8aS)-7,8-dihydroxy-2-methyl-hexahydro-2H-pyrano[3,2-d][1,3]dioxin-6-yl]oxy}-10-(4-hydroxy-3,5-dimethoxyphenyl)-4,6,13-trioxatetracyclo[7.7.0.0^{3,7}.0^{11,15}]hexadeca-1,3(7),8-trien-12-one