Description
β-Lapachone (4707-32-8) is a naturally occurring quinone found in the bark of the Lapacho tree (Tabebuia avellanedae). A novel DNA topoisomerase I inhibitor which unlike camptothecin does not stabilize the cleavable complex indicating a novel mode of action.1?Induces apoptosis in a number of cancer cell lines.2?In cancer cells over-expressing NAD(P)H:quinone oxidoreductase, reduction of β-lapachone leads to futile cycling between quinone and hydroquinone forms3?resulting in the production of reactive oxygen species4. Suppresses radiation-induced activation of NFκB.5
Chemical Properties
Orange Solid
Uses
β-Lapachone has been used:
- as an anticancer compound in catalase-inhibitable luminol/hydrogen peroxide (HRP)-dependent chemiluminometric?assay in Lewis lung carcinoma (LLC) cells and isolated mitochondria
- as a naphthoquinone to study its effects on the growth and differentiation of mice granulocyte and macrophage progenitor cells
- as a substrate to study the enzyme activity of human recombinant NAD(P)H dehydrogenase 1 (NQO1) protein
Uses
β-Lapachone is a naturally occurring quinone obtained from the bark of the lapacho tree (Tabebuia avellanedae) with cancer chemopreventive properties. Induces apoptosis in HL-60 and human prostate cancer cells.
Definition
ChEBI: A benzochromenone that is 3,4-dihydro-2H-benzo[h]chromene-5,6-dione substituted by geminal methyl groups at position 2. Isolated from Tabebuia avellanedae, it exhibits antineoplastic and anti-inflammatory activi
ies.
Biochem/physiol Actions
β-Lapachone acts as a DNA topoisomerase type I inhibitor. It exhibits anti-fungal, anti-bacterial, trypanocidal, and antiviral properties. β-Lapachone also inhibits nitric oxide?(NO) and inducible NO synthase (iNOS) in alveolar macrophages.
References
1) Li?et al.?(1993),?beta-Lapachone, a Novel DNA Topoisomerase I Inhibitor With a Mode of Action Different From Camptothecin; J. Biol. Chem.,?268?22463
2) Wuerzberger?et al.?(1998),?Induction of Apoptosis in MCF-7:WS8 Breast Cancer Cells by Beta-Lapachone; Cancer Res.,?58?1876
3) Pink?et al.?(2000),?NAD(P)H:Quinone Oxidoreductase Activity Is the Principal Determinant of Beta-Lapachone Cytotoxicity. J. Biol. Chem.,?275?5416
4) Siegel?et al. (2012),?NAD(P)H:quinone Oxidoreductase 1 (NQO1) in the Sensitivity and Resistance to Antitumor Quinones; Biochem. Pharmacol.,?83?1033
5) Dong?et al.?(2010), Beta-lapachone suppresses radiation-induced activation of nuclear factor-kappaB; Exp. Mol. Med.,?42?327
