 |
S K Sahoo, Ph.D.
Scientist
Institute of Life Sciences
Nalco Square
Bhubaneswar-751023, India
Office:
0091 674 2300137/ 2301476 ext. 221
Fax: 0091 674 2300728
Email: sanjeeb@ils.res.in,
sanjeebsahoo2005@gmail.com
|
|
Research:
Magnetic nanoparticles as a theranostic tool in
cancer therapy-
Magnetic nanoparticles (MNPs) are a class of
nanoparticles (i.e., engineered particulate
materials of 100 nm) that can be manipulated
under the influence of an external magnetic
field. MNPs are most commonly employed for
biomedical applications due to their
biocompatibility and stability. Presently, MNPs
are being exploited for their theranostic
applications. The principles of magnetic
guidance of MNP-conjugated drugs have been
applied experimentally, and have reached
clinical trials as a cancer therapy. Apart from
that, currently significant attention has been
laid down for the multifunctional
characteristics and complementary role of MNPs
as a contrast agent for the magnetic resonance
imaging (MRI), which can be easily assimilated
in the human body. MRI is currently a very
popular noninvasive imaging technique that
differentiates pathological and normal tissues
based on the relaxation properties of hydrogen
atoms in water. The imaging property of MNPs
helps to track the systemic distribution of
drug-carrier complexes prior to and after drug
release to ensure therapy success.
Polymer therapeutics in cancer -
“Polymer therapeutics”, a technological podium
in the field of nanomedicine, has emerged as one
of the most promising platform for the efficient
delivery of anticancer agents for the
chemotherapy of cancer. Conjugation to polymers
saves the fate of these promising drugs since a
specific water soluble polymer, is linked by a
biodegradable polymer-drug linker to these
agents to increase their hydrodynamic size for
prevention of rapid renal clearance. In this
system, PEGylation has emerged as a trailblazer
innovation. The chemical coupling of
polyethylene glycol (PEG) chains to the drug
molecules increases their apparent molecular
weight (Mw) and thus extends their circulating
half-lives. PEG is an outstanding drug delivery
vehicle given that it is water-soluble,
biocompatible, nontoxic, and non-immunogenic
material; accepted by FDA for human intravenous,
oral, and dermal applications. The drugs upon
PEGylation adapt the strategy of passive tumor
targeting by taking the advantage of Enhanced
Permeability and Retention (EPR) effect in tumor
vasculature. PEGylation has already been an
effective strategy for enhancing the therapeutic
index of various protein and non-protein drugs.
In this regard, several pegylated peptides &
proteins have been successfully launched in the
market as a therapeutic agent, coupled with the
transfer of few PEGylated drugs entering into
clinical trials for several solid tumors. This
has provided a firm groundwork for more
sophisticated PEGylated drug constructs that
deliver the anticancer agents (e.g. modulators
of cell cycle, signal transduction inhibitors
and antiangiogenic drugs) for the cancer
therapy.
Dual drug loaded nanocarrier as therapeutic
strategy for cancer treatment-
Due to the high frequency of cancer, the use of
chemotherapy to evoke cure or prolongation of
survival has become critically important.
Research in cancer drug development achieved an
experimental breakthrough in the simultaneous
use of two or more chemotherapeutic agents for
treating cancer, known as combination therapy.
Ideally, the combination of two or more agents
should be more effective than each agent
separately due to synergistic effect, although
additive and even antagonistic combinations may
result in a higher therapeutic efficacy in the
clinic. Currently, nearly all successful cancer
chemotherapy regimens use multiple drugs in
combination as a cocktail having antimetabolites
for treatment of a broad spectrum of tumors.
Synergistic combinations of two or more agents
can overcome toxicity and other side effects
associated with high doses of single drugs by
countering biological compensation, allowing
reduced dosage of each compound or accessing
context-specific multitarget mechanisms. Much
interest is currently focused on the development
of combination therapies to prevent relapse of
cancer. Moreover, activation of multiple
biochemical cascades after dual drug treatment
supports the evolving concept that such dual
drug loaded strategy can be used for cancer
therapy in near future. Presently, our
laboratory has been involved in preparation of
such type of dual combination nanoparticles and
its therapeutic efficacy has been exploited for
the treatment of leukemia and other
malignancies.
|