Actinomycetes are also a type of bacteria having filamentous or rod like shape. Many marine actinomycetes are found to be effective against many forms of cancer.
Thiocoraline is a compound obtained from a marine micro-organism i.e. Micromonospora marina, is found to be effective against colon cancer, lung cancer and melanoma.
Components in Actinomycetes:
Components, that are found in Actinomycetes and have anti-tumor activity, are anthracyclines, indolocarbazoles, macrolides, enediynes, isoprenoides, non-ribosomal peptides and others.
Many compounds have been derived from type-I polyketides, found in marine actinomycetes, that have antitumor activity.
Mechanism by which the components act as antitumor:
The mechanism by which they exert anti-tumor activity may include one or combination of the followings:
- Induction of apoptosis through DNA cleavage that is mediated by the inhibition of the enzyme topoisomerase-I or II
- Hindrance of the key enzymes in signal transduction like proteases or metabolism of cells
- Mitochondria permeabilization or
- Inhibition of tumor induced angiogenesis
Anti-tumor drugs from Actinomycetes:
Several clinically useful anti-tumor drugs are produced by Actinomycetes such as
- Aclarubicin, doxorubicin and daunomycin are produced by anthracyclines
- Actinomycin-D and bleomycin are produced by peptides
- Mithramycin is produced by aureolic acids
- Neocarzinostatin is produced by enediynes
- Pentostatin is produced by antimetabolites
Olano, C. et. al. (2009). Antitumor Compounds from Marine Actinomycetes. Marine Drugs, 7(2): 210–248.