Lets talk about natural ANTI-CANCER DRUGS

Another post based on another of my research proposal...

There are several anticancer drugs made from precursors obtained from plant extracts..lets see one of them..

Podophyllotoxin is an important natural lignin, used as a precursor for the synthesis of effective anticancer drugs like etoposide and teniposide which are used in the treatment of lung cancer, testicular cancer, a variety of leukemias and other tumours. It is a pharmaceutically active cytotoxin which acts by inhibiting the assembly of microtubules, leading to arrestation of cell division in the metaphase stage of mitosis. Due to its detrimental side-effects in natural form, its derivatives were synthesized which were produced into FDA approved drugs like etoposide, etc. Podophyllotoxin is also the precursor of novel drugs aimed to treat diseases like rheumatoid arthritis, veneral warts, measles, herpes, etc. Thus it is a very important natural drug. But, its commercially exploitable plant sources are few. One of the few exploitable species is Podophyllum hexandrum Royle or the Indian Podophyllum, a perennial rhizome found in the Himalayas. It has slow growth phase and is considered a 'critically endangered' plant. Also, total chemical synthesis of podophyllotoxin is complicated and expensive. Thus, several biotechnological approaches especially plant cell cultures have been attempted and recorded.

Many research papers record attempts being made to improve the accumulation of podophyllotoxin in in vitro cultures by optimizing culture conditions and nutrient levels, addition of elicitors and precursors, immobilization, etc. with varied success.

Bioreactor scale production represents the final stage leading to commercial production. Although a number of important phytochemicals have been produced by plant cell culture techniques, production on an industrial scale is still not extensive. Major factors that need to be focused on are: increasing the rate of growth of plant cells, production of a genetically stable cell line, optimization of sterilization procedure, meeting oxygen demand without hampering the process, prevention of shear, growth and production media optimization, type of reactor, inoculum density, etc.

Works reviewed:

11)      Majumder A, Jha S, “Biotechnological Approaches for the Production of Potential Anticancer leads Podophyllotoxin and Paclitaxel: an Overview”, e Journal of Biological Sciences, 2009, Dec; Volume 1, Issue 1.

22)      Farkya S, Bisaria VS, Srivastava AK, “Biotechnological Aspects of the Production of the Anticancer Drug Podophyllotoxin”, Appl Microbiol Biotechnol, 2004, Oct; 65(5):504-19. Epub 2004, Jul 28.

Drug Delivery and something else...

My new post...

This was actually my research proposal for an internship though I modified it a bit.

Please comment if you like it, dislike it or have any views..

Scientists and Engineers have from time immemorial tried to follow the perfection of nature in their works. Biological systems and processes have always intrigued and inspired man. In the recent years, there has been a growing interest in biomimetic methods to build bio-hybrid systems and bio-mimetic materials for drug delivery, drug testing and tissue engineering devices. Now Nanotechnology has enabled manipulation and control at molecular scale to mimic biological systems. This has led to an bloom in the biomimetic world leading to production of nano-structured tissue scaffolds and biomaterials for tissue repair and construction, bionanopores for probing, analyzing and sequencing of biological macromolecules, self-assembled novel biomaterials with molecular precision. 

An interesting theme is the design and development of micro and nanofabricated devices, like self-assembled drug delivery devices that aim to combine diagnostic and therapeutic actions for real-time analysis of targets and instantaneous administration of therapy. The recent advances of biotechnology and related areas have resulted in the discovery and design of several novel drugs and therapeutics. But most of the drugs still have limited action due to their pure solubility, nonspecific delivery, in vivo degradation, non-adaptability and unacceptability by body. Thus, effective targeted drug-delivery systems are essential for on-site administration of these new advances into clinical effectiveness. Additionally, they will increase patient compliance, extend product life cycle, offer strategic tool to repackage classic drugs and reduce healthcare costs.

This will have great implications in treating diseases like cancer where time is of prime importance. Several detailed research has been done in developing and studying the drug delivery of nanoparticles (NPs) in cancerous tissues by passive targeting, e.g. Doxil which acts by the enhanced permeability and retention (EPR) effect on ovarian cancer, metastatic breast cancer and AIDS-related Kaposi’s sarcoma; DOC (sodium deoxycholate)-heparin NPs for in vivo tumor targeting and inhibition of angiogenesis using EPR effect; tumor-targetting of cisplatin-loaded glycol chitosan NPs; localized delivery of transferrin (Tf) conjugated paclitaxel (Tx)-loaded biodegradable NPs to treat local cancers like prostrate, head and neck cancers; etc. and active targeting, e.g. PEGylated gold NPs decorated with various amounts of human Tf showed enhanced targeting, PLGA NPs surface-modified with monoclonal antibodies showed active targeting of cancer cells, aptamer (oligonucleotides that selectively binds to targets with high affinity and specifity)-coated paclitaxel-polylactide nanoconjugates having enhanced targeting to cancer cells,etc.  

The speed and precision with which a cancer is detected and treated has momentous implications.  Consequently, the designing of point-of-care(POC) diagnostic devices, e.g.  micro total analysis systems (µ-TAS) that enable diagnostic testing at the site of care and the immediate targeted supply of nanofabricated drugs at the site will substantially abbreviate analysis time and drug action time and decrease gap time between them, leading to exceptionally effective treatment. There is a long way to go before these dreams are realized, but hardcore research is the key to it.

Works Reviewed:

1)      Hilt J. Zachary, Nanotechnology and biomimetic methods in therapeutics: molecular scale control with some help from nature, Advanced Drug Delivery Reviews: 56 (2004), 1533– 1536.

2)      Parveen Suphiya, Misra Ranjita, Sahoo Sanjeeb K., Nanoparticles: a boon to drug delivery, therapeutics, diagnostics and imaging, Nanomedicine: Nanotechnology, Biology, and Medicine: 8 (2012), 147–166.

3)      Murday et al, Translational nanomedicine: status assessment and opportunities, Nanomedicine: Nanotechnology, Biology, and Medicine: 5 (2009), 251–273.

4)      Tirrell et al, The role of surface science in bioengineered materials, Surface Science: 500 (2002), 61–83.

5)      Langer R. and Peppas N.A., Advances in Biomaterials, Drug Delivery, and Bionanotechnology, Bioengineering, Food and Natural Products (book).

BIOMIMETICS-not another bio word..

So, here is my first post..

Biomimetics...what does the name suggest? No, its not an insect..Bio mimic? Mimicking Biological systems? Somewhat in the line. Biomimetics is the science of creating artificial materials and structures inspired by nature. Yeah, you could have googled the meaning. But I'm not here to give you word meanings or act as a translator for bio language. I'm here to tell you about the impact this word has on recent science and  technology and its research possibilities.

Let me start with a better known word-Nanotechnology. Yeah, that's something you would have heard and I guess many of you know quite a lot about it. Nanotechnology is the manipulation of materials at the nano level i.e. at the molecular and even atomic level. This new venture of science is not quite so new in reality. Scientists have been investigating matter at the molecular level since a very long time. But the actual manipulation at the nanoscale has been possible only in the last decade. This has resulted in the reshaping of the foundations on which basic science is based. We can design new substances from the very basic level. Just imagine the possibilities. Well, its not really that simple. There's still a very long way to go. But the implications of nanotechnology has already been visible in these last few years. Biochemists have been engineering molecular drug delivery systems; electrical engineers regularly etch features on chips less than 100 nm across: new polymers with better strength and other requisite qualities are being researched. There are national initiatives, billions of dollars in investment, convention-sized events, and whole publications devoted to nanotechnology. Nano is indeed big: a rallying cry marshalling an all-out assault on the next frontier in research.

So what has nanotechnology to do with biomimetics? No, they are not synonymous. Neither is one a part of another. Nanotechnology is one of the many tools by which we can use biomimetics. If you want synonyms to biomimetics-then they are biomimicry,bionics,etc. But you wont understand the meaning with a synonym, would you? In the simplest sense, bionics means the creating of anything resembling something in nature. Anything means anything. If you design a costume resembling an animal, if you design something based on natural occurrences(velcro), etc. All engineering is actually bionics. Biomimetic materials are the materials created resembling natural systems. Biomimetics is now being used for tissue engineering, tissue repair and most importantly, drug delivery. In the recent years, there has been a boom in research in the design, development and characterisation of  novel micro fabricated and nanofabricated devices for drug delivery. Such devices seek to develop a  platform of well-controlled functions at micro and nanoscales. 

In addition, biomimetic methods are now used to build bio hybrid systems or even biomimetic  materials for drug delivery, drug testing and tissue engineering devices. The synthesis and  characterization of biomimetic gels and molecularly imprinted drug release and protein delivery systems are significant focus of recent research. In particular, biomimetic methods are facilitating the fabrication and assembly of materials and  devices with molecular precision. In the near future, self-regulated micro-nanoscale drug delivery devices that will combine diagnostic and therapeutic actions will be created, enabling for real-time monitoring of target analyses and instantaneous administration of therapy. Interest and investment in this maturing field will continue to grow, and the resulting technologies will dramatically influence the nature and practice of medicine. 

With the largest investments being made in the healthcare sector, biomimetic materials have become one of the hottest areas of research.

In one of my next posts, I will deal with the concept of drug delivery.

Declaration

Hii,everybody!!!!

I'm going to start an online journal dealing with the latest trends of the biotech world and its implications in our day-to-day life. I know there are several online journals of this type and my blog may be nothing new. But, I would try my best to show how biotechnology has impact in each and every sector of science and commerce in this era and its far-reaching potentials in research and enterprise. I promise my language will be as simple and lucid as it can get.

I'm a junior in college studying Bachelor of Engineering in Biotechnology which is an amalgamation of molecular biology and chemical engineering. I have had the honor to be involved in several research projects both in my college and in other colleges under the guidance of esteemed researchers. Being a college student in a premier institute majoring in a comparatively new subject, I have faced both the challenges and stigma associated with new ventures. Biotechnology was my passion since high school and through this journal, I wish to show how important studying new technologies and embracing changes is to a society for its survival. 

I'm an amateur writer. So, I apologize at the very outset for the mistakes that may creep into my writing as there won't be anyone to review my writings except me myself. I would try my best to be avoid  any religious or ethical issues that may hurt anyone's sentiments. 

Thanking you in advance,

Yours

Anindita Roy