tumor homing self-amplifying drug-carrying nanomolecules

[Lani]

Hope over tumour fighting therapy

The technique could stop vital nutrients reaching tumours
Scientists believe they have found a way to block the supply of nutrients to cancer tumours.
Researchers mimicked the action of blood cells known as platelets by creating tiny nanoparticles to create clots to stop blood getting to tumours.

The particles may also be able to deliver chemotherapy drugs to the area, the California University team said.

The study, carried out on mice, was published in the Proceedings of the National Academy of Sciences journal.


The use of nanoparticles to deliver drugs to tumours is an exciting prospect for the future of cancer treatment, and is the subject of much research
Dr Anthea Martin, of Cancer Research UK

The researchers used the nanoparticles to zero in on the network of blood vessels that supply the tumours in mice with nutrients and oxygen.

A potentially powerful function of nanoparticles is the ability to home in on particular targets inside the body.

While various nanoparticles have been designed to target tumours, the efficiency is relatively low.

The researchers developed a technique for amplifying this homing ability by designing a multifunctional nanoparticle that binds to a protein structure found only in tumours and associated blood vessels.

To test the particles' homing ability, the researchers injected the nanoparticles into mice and found that the particles bound only to tumour vessels.

Upon binding, the particles induced selective blood clotting that attracted more nanoparticles, reminiscent of platelet and clotting action.

Tests

The tests showed that within hours of the injection, the artificial platelets began blocking the supply without harming normal tissues.

The scientists believe the nanoparticles could also be used to carry drugs to the tumour.

Lead researcher Dr Erkki Ruoslahti said: "Nanoparticle-based diagnostics and therapeutics hold great promise because multiple functions can be built into the particles.

"One such function is an ability to home to specific sites in the body.

"We envisage the design of drug-carrying nanoparticles that accumulate in tumour vessels and slowly release the drug payload while simultaneously occluding the vessels."

Dr Anthea Martin, cancer information officer at Cancer Research UK, said it was an exciting area of research, but there was still some way to go before it would be available to patients.

"The use of nanoparticles to deliver drugs to tumours is an exciting prospect for the future of cancer treatment, and is the subject of much research.

"The unique feature of this system is that once the particles start to bind to the tumour, they increase the rate at which more nanoparticles bind, setting off a chain reaction that leads to more and more nanoparticles binding.

"The system has not been tested in patients yet, but we look forward to hearing the results of further research."