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Year : 2010  |  Volume : 47  |  Issue : 1  |  Page : 87--88

Polyhydroxyalkanoates: Important in cancer and other drug discovery systems

R Jain1, S Kosta2, A Tiwari2,  
1 Piramal Life Sciences Limited, Nirlon Complex, Goregaon (E), Mumbai-63, India
2 School of Biotechnology, Rajiv Gandhi Proudyogiki Vishwavidyalaya, Airport Bypass Road, Gandhi Nagar, Bhopal-462 036, M.P, India

Correspondence Address:
S Kosta
School of Biotechnology, Rajiv Gandhi Proudyogiki Vishwavidyalaya, Airport Bypass Road, Gandhi Nagar, Bhopal-462 036, M.P

How to cite this article:
Jain R, Kosta S, Tiwari A. Polyhydroxyalkanoates: Important in cancer and other drug discovery systems.Indian J Cancer 2010;47:87-88

How to cite this URL:
Jain R, Kosta S, Tiwari A. Polyhydroxyalkanoates: Important in cancer and other drug discovery systems. Indian J Cancer [serial online] 2010 [cited 2020 Aug 5 ];47:87-88
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The resistance of synthetic polymers to biodegradation and their persistence in soil environment for a long time is one of the resulting problems of modern engineering and scientific development. However, inquisitive researchers sought a solution for this problem in the form of a biopolymer obtained from microorganisms or from plants, which are genetically engineered to produce such polymers and are likely to replace currently used synthetic polymers as plastics. [1] Known examples include high-molecular-weight polymeric compounds derived from microbes such as polyhydroxyalkanoates (PHAs), poly-3-hydroxy-n-butyric acid (PHB), polysaccharides, for instance, bacteria cellulose and pullulan, and polyamino acids, for example, poly-.gamma.-glutamic acid and polylysine. [2] Among the biodegradable polymers, polyhydroxyalkanoates (PHA) have been intensively investigated in targeted drug delivery systems as a vector for targeting drugs, particularly for one of the biggest medical challenge, cancer. PHA is composed of chiral hydroxyacids that have potential as synthons for anticancer drugs, anti-human immunodeficiency virus drugs, antibiotics, and vitamins. [3] Importantly, it has been observed that PHA-degraded products, including monomers and oligomers, are not harmful to the surrounding tissues and are compatible with a living body, thus, are expected to be imperative as soft materials for medical purposes.

A step ahead of the well-known fact that nanoparticles are useful as excipients in the treatment of diseases, a receptor-mediated, drug-specific, delivery system has been reported by scientists, based on the polyhydroxyalkanoates (PHA) granule binding protein PhaP (PHA granule-associated proteins). PHA granule-associated proteins (also called phasing) are accumulated at high levels in the PHA producing microorganisms. This system includes PHA nanoparticles, PhaP, and ligands fused to PhaP.

An experimental article published in "Biomaterial" described how PHA nanoparticles were used to package mostly hydrophobic drugs as drug carriers. PhaP fused with ligands were produced by over-expression of their corresponding genes in recombinant microorganisms. The researchers were able to attach the PhaP-ligands to hydrophobic PHA nanoparticles containing rhodamine B isothiocyanate (RBITC). Transplantable murine hepatoma22 (H22) model cells were used to evaluate the in vivo targeting effects of novel delivery systems, based on PHA nanoparticles on murine liver cancer, while the in vitro effects were evaluated on macrophages isolated from male Bal b/cAn mice, six to eight weeks of age (Shanghai Slac Laboratory Animal Co. Ltd, Shanghai, China), hepatocellular carcinoma cell Bel7402, 293FT cell line, and murine hepatoma22 cells. Furthermore, the ligand-PhaP-PHA nanoparticle specific drug delivery system was proven effectively both in vitro and in vivo.[4]

Being a biocompatible material for in vivo applications and an implantable tissue engineering material for hard tissue replacement, regeneration, and wound healing, PHA is a significant candidate in drug research.


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