Treating cancer with light-sensitive nanoscale biomaterials

New approaches using nanoparticles show some promise in improving existing techniques.

One technique, known as photothermal therapy (PTT), converts laser light into heat that can target and kill tumour cells. Another technique, photodynamic therapy (PDT), uses laser light to generate reactive Oxygen species (ROS), such as hydroxyl radicals, singlet Oxygen, superoxide radicals, and Hydrogen peroxide, which can wreak devastation on tumour cells.

The nanoparticles can be used to deliver chemotherapeutic agents or antibiotics to the tumour site. When light is applied, generating ROS molecules in the tumour and killing both tumour cells and bacteria, the antibiotics can be released to prevent infection in the treated area.

Other modifications to the nanoparticle surface could allow it to cross the blood-brain barrier so that brain tumours can be treated.

One set of studies reviewed in this work involved gold nanorods that had a glycoprotein from the rabies virus attached to their surface. Since this virus naturally infects the brain, the gold nanorods were able to penetrate the blood-brain barrier and target the brain tumour. Applying light from a laser then allowed the nanorods to generate localized heat, killing the tumour cells.

These techniques can also be used to treat other medical issues, such as atherosclerosis, scar removal, abscesses, nonhealing ulcers, or dental infections.