Nanotherapy for targeted cancer treatment

Many researchers are currently investigating more effective, targeted ways of delivering cancer drugs and therapies to patients.

Two such innovative studies have looked at the use of wheat germ agglutinin and folic acid, respectively, as a conjugate to target tumors.

A team in Singapore have modified the nano-encapsulated drug, paclitaxel, with wheat germ agglutinin (WGA) to target colon cancer cells.¹ These cells express a greater amount of WGA-binding glycoproteins. Nanoparticles modified with WGA showed greater uptake into cancer cells when compared to unmodified particles. The WGA-modified particles also showed an enhanced anti-proliferative activit.

In India, a research team have modified nanoparticles loaded with grape seed extract(active as a neutraceutical), in order to target them to folate receptor over-expressing cancers.² The nanoparticles were conjugated with folic acid in order to target them to these cells. Folate receptor positive cancer cells readily took up the nanoparticles, showing enhanced bioavailability to tumor cells, sparing the normal ones.

Both these reports underline the application of modifications to target cancer therapies - strategies that may greatly improve the side-effects of chemotherapy.

¹ Wang C, Ho PC, Lim LY. Wheat germ agglutinin-conjugated PLGA nanoparticles for enhanced intracellular delivery of paclitaxel to colon cancer cells. Int J Pharm 400:201-10 (2010).

² Narayanan S, Binulal NS, Mony U, Manzoor K, Nair S, Menon D. Folate targeted polymeric 'green' nanotherapy for cancer. Nanotechnology 21:285107 (2010).

Neurorehabilitation - gaming systems

In a marriage of medicine and gaming culture, virtual reality games have been investigated in the rehabilitation of stroke patients.¹

Researchers in Barcelona have investigated novel technology-based neurorehabilitation techniques in the treatment of strokes. A special aspect of this technique was the fact that the game could be adjusted and personalized for each patient.

While a stroke causes massive damage, brain cells can reorganize themselves. Therefore the aim of rehabilitation is to maximize the effect of this plasticity. The Spanish research team developed the Rehabilitation Gaming System (RGS), a virtual reality-based neurorehabilitation program .

The RGS tracks arm and finger movements and maps them onto a virtual environment. The user controls the movement of two virtual limbs that are viewed on a screen. The RGS "game" that the researchers used was called Spheroids (see figure below). In this game the user has to catch and place spheres that move towards them. The idea behind this is that, when the patients use their limbs and observe the virtual limbs move in a way that is controlled by them, conditions are created that stimulate the reorganization of neurons involved in motor functions.


The researchers also tried to make the tasks just challenging enough to remain engaging for the patients. The RGS automatically adjusts the difficulty of the task with respect to the measured performance of a subject in order to keep them encouraged and to maximize effect.

The researchers concluded that the RGS is a promising neurorehabilitation tool that can be used to alleviate the deficits brought on by lesions to the central nervous system as the ones caused by stroke.

¹ Cameirão MS, Bermúdez i Badia S, Oller ED, Verschure1 PFMJ. Neurorehabilitation using the virtual reality based Rehabilitation Gaming System: methodology, design, psychometrics, usability and validation. Journal of NeuroEngineering and Rehabilitation 7:48 (2010).
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Stem cell therapy for cardiovascular disease

Stem cell therapy is controversial, mostly for the application of foetal stem cells in a large proportion of research.

A new type of stem cell has been developed by researchers in Japan, called induced pluropotent stem (iPS) cells. These cells derive from somatic (body) cells, and therefore are a lot less morally questionable than foetal cells.

A recent study has investigated the usage of iPS cells in the treatment of ischemia ¹ - the restriction of blood supply to a specific body part that can lead to tissue damage. Hind limb ischemia in mice was treated with iPS cells specifically treated to produce a protein called fetal liver kinase-1 (Flk-1). This protein plays an important role in the formation of blood vessels.

Transplantation of stem cells producing Flk-1 into the damaged limbs of mice accelerated the formation of new blood vessels, showing that this therapy could potentially rescue tissues that have suffered restricted blood flow. This could potentially be applied after events such as heart attacks.

¹ Suzuki et al. Therapeutic angiogenesis by transplantation of induced pluripotent stem cell-derived Flk-1 positive cells. BMC Cell Biology 11:72 (2010)