NUS researchers discover technology that paves way for safe treatment of deep cancer

Researchers from the National University of Singapore (NUS) have discovered a technology that paves the way for a new safe and non-invasive method of treating deep cancer. 

The team has proven that the technology could inhibit tumour growth and control gene expression in mice. 

NUS said on Monday that this is a world's first for the use of nanoparticles for non-invasive photodynamic therapy of deep cancer. 

The team discovered a way to control gene expression by using nanoparticles which are able to convert near-infrared (NIR) light to visible or UV light. 

These nanoparticles can be introduced into target sites of the patient to do their good work. 

Genes release certain proteins in the body to ensure that its internal "machinery" works well to stay healthy. 

However, sometimes, the process can go awry and cause the body to malfunction, leading to various disease. 

Doctors can put this right by manipulating the process of gene expression by using UV light. 

However, UV light may cause more harm than good. 

Team leader, Associate Professor Zhang Yong, said NIR is non-toxic and can penetrate deeper into the tissues. 

When NIR reaches the desired places in the body of the patient, the nanoparticles invented by the NUS researchers are able to convert the NIR back to UV light (up-conversion) to effectively activate the genes in the way desired - by controlling the amount of proteins expressed each time, as well as when and how long it should take place. 

As the up-conversion nanoparticles can also be used to produce visible light, the team has extended its application to other light-based therapies. 

Conventional light therapy for treating tumours uses visible light to activate light sensitive drugs that can kill cancer cells. 

However, such visible light is not penetrative enough to reach deep-seated tumours. 

The team's method of employing NIR is able to penetrate much deeper. 

The discovery promises a wide range of applications.

"By using our nanoparticles, drugs can be activated by NIR light which is safe. The light is also able to penetrate deeper into tissues to treat diseased cells," said Prof Zhang. 

For example, the innovation can be used for bioimaging, where the nanoparticles can be attached to biomarkers, which will then attach to cancer cells and allow for better imaging of tumours and cancerous cells. 

The six-member team comprises researchers from the faculties of Engineering and Science, as well as the NUS Yong Loo Lin School of Medicine. 

It's now working with researchers at the National Cancer Centre Singapore on a project funded by the Agency for Science, Technology and Research (A*STAR) to assess the safety and efficacy of the technology to pave the way for pilot clinical trials. 

The team's findings have been published online in Nature Medicine.