Chemotherapy nanorobots hit tumours where it hurts

16 August 2016

Fusion of nanotechnology and bacteria used to create self-propelled and guided carriers, able to deliver drugs to the hypoxic regions of tumours, where they have the greatest effect.

As a tumour grows it outstrips its blood supply, resulting in portions of the tumour with not enough oxygen, known as hypoxic regions. These regions are resistant to most therapies, including radiotherapy and can play a role in driving tumour progression. Successfully delivering drugs to hypoxic regions is difficult, the reduced blood flow means that treatments don’t often achieve adequate penetration, resulting in the need for increased dosages with adverse effects. 

As an attempt to tackle the problem of hypoxic tumour regions, researchers from Polytechnique Montréal have developed a nanobot capable of propelling and guiding itself, delivering its payload of chemotherapy drugs to where they can do the most damage.

The robots utilise the Magnetococcus marinus bacterium. This bacteria propels itself by movement of its flagella in the direction of a magnetic field, and naturally seeks low oxygen concentrations. Once combined with drug loaded nanoliposomes the bacterium is guided by a computer controlled magnetic field, once it reaches the tumour, the bacterium’s own targeting mechanism means that it will head for the hypoxic regions.

The research, published in Nature Nanotechnology on Monday 15 August, details the results of their testing, which they carried out on mice.

Professor Martel, from the nanorobotics laboratory of Polytechnique Montréal, and one of the authors, argues that: ‘Chemotherapy, which is so toxic for the entire human body, could make use of these natural nanorobots to move drugs directly to the targeted area, eliminating the harmful side effects while also boosting its therapeutic effectiveness’.