Might we one day pop a nano-pill to stop cancerous cells before they aggregate into tumours or metastases? Julia Ljubimova, MD, director of the Nanomedicine Research Center at Cedars-Sinai in Los Angeles, believes we might.
Her team is at the forefront of both detection and targeted treatment of metastasised tumours of the brain. In April, the team received its latest grant from the National Institutes of Health, $2.5m to further research into what the oncologist calls a “virtual biopsy” followed by targeted drug delivery. Under this approach, a biodegradable, nano-sized polymer less than the width of a human hair is armed with tracers that detect cancer biomarkers. Visible on an MRI, the tracers accumulate at the site of the cancerous cells and diagnose what kind of cells (breast, lung, etc) they are. After this “virtual biopsy”, a nanotech delivery system, armed with drug(s) tailored to the specific mutations, delivers the payload directly to the tumour.
Dr Ljubimova could see the technology some day detecting and targeting tumours originating in the brain. Brain tumours are notoriously difficult to treat, in part because the molecular structures of most chemotherapy drugs are too large to penetrate the blood-brain barrier (BBB), the system of protective blood vessels that surround the brain.
“Nanotechnology-based platforms may be our best hope for penetrating it,” says Dr Ljubimova.
MagForce AG, a German company, couldn’t agree more. The company uses nanotech to cross the BBB but bypasses drugs altogether: Once its iron nano-particles reach the brain tumours, they are heated to render tumours either more vulnerable to chemotherapy or to destroy them altogether. Commercial treatment of brain cancer patients using the technology recently commenced at Cologne University Hospital.
Targeting tumour cells with nanotechnology is not as easy at is sounds. Nanostructures tend to be unstable and insoluble in water—an issue in the largely aqueous human body. They also tend to clump, raising questions about how they would safely exit the body.
Dr Ljubimova’s team favours the employment of a natural, biodegradable polymer. Others are experimenting with nanodiamonds. Sonia Trigueros, MD, of Oxford University takes a different approach: She wraps carbon nanotubes in DNA to increase their stability and lower the chance of an immune response.
Another challenge is targeting cancer cells that have spread.
“Metastases, not primary tumours, tend to be what kill patients,” says Sofia D. Merajver, MD, who heads the breast oncology programme at the University of Michigan’s Comprehensive Cancer Center. Her research uses nano and micro technologies to tease out the gene expression of the most aggressive, mobile cells and understand better their high metastatic potential. Little is understood about why certain cells spread and others don’t.
Not all barriers are technical, however. Raising money, say all the scientists interviewed, is the biggest hurdle of all. Dr Ljubimova’s NIH grant does not cover clinical trials. Dr Trigueros, who hopes a nano-pill could one day destroy hazardous cells before they aggregate into a tumour, says she spends 80% of her time fund-raising for trials and calls lab time a “luxury”. Dr Merajver adds, “Cancer could be a chronic disease, not a death sentence. We have invented everything we need [for this research]. The only thing we’re limited by is money.”
Nanotech may be small, but in view of its potential for fighting cancer, investments in it should be anything but nano.
This article is published in collaboration with GE Look Ahead. Publication does not imply endorsement of views by the World Economic Forum.
To keep up with the Agenda subscribe to our weekly newsletter.
Author: Holly Hickman writes for GE Look Ahead.
Image: A radiologist examines the brain X-rays of a patient who underwent a cancer prevention medical check-up. REUTERS/Rupak De Chowdhuri