To materials chemist Dale Huber (1132), most people remain unaware they have cancer precisely when the knowledge could help them most: when the number of harmfully mutating cells are treatably small.
But in a kind of catch-22, Dale says, when the number of mutant cells are still trivial, they fall below the detection threshold of current sensors. So when preventive action would be easiest, nothing is done.
“For example, mammography has a long history of not working well enough for early cancer detection,” Dale says. “The tumor has to be big and obvious. The radiologist has to be able to read it in the image.”
Improving early detection of cancerous cells is a particularly poignant problem when it comes to children, Dale says. “Leukemia is the number one childhood cancer. Even successfully treating it can knock as many as 20 IQ points off a developing child, according to some published studies.”
‘Left the comfort zone’
To help improve early detection capabilities, Dale has left his comfort zone of (as he puts it) “squishy soft polymers” and instead is working with iron oxide nanoparticles in the Sandia/Los Alamos national laboratories joint Center for Integrated Nanotechnologies, where he is a principal member of the technical staff. (CINT is sponsored by DOE’s Basic Energy Sciences office.)
Providing technical backup in an approved “user” project to retired LANL researcher Ed Flynn and his company Senior Scientific LLC, Dale uses CINT technologies to help grow iron oxide nanoparticles 20 to 30 nanometers in diameter that ride antigens designed to home in on the cells of a particular cancer.
Antigens that locate cancerous cells bind to those cells’ receptors, stabilizing their magnetic riders. Those antigens which locate no cancers go whirling off harmlessly, essentially lost in space (or rather, the bloodstream), iron oxide nanoparticles destabilized.
By subjecting the patient to a magnetic field that lasts three-tenths of a second, a clear signal is yielded by those nanoparticles attached to a stable base. Those unattached to a cancerous cell are rotated by random motion in a way that cancels any response. Thus, a signal is provided only from those iron oxide particles attached to cancerous cells.
The beauty of the system is that even cancer distributed throughout the body can be detected. The new system shows their location clearly.
“Death comes when the number of cancer cells in the body reach, roughly, 10 to the 12th power,” Dale says. “At 10 to the 9th power, the cancer is palpable. X-rays can detect cancers in amounts 10 to the 8th power. Our method, with its unambiguous signal, can detect it at 10 to the 4th power, literally doubling the time to treat the cancer.” Additional treatments, he says, should greatly improve survival rates from microtumors.
Could locate Alzheimers sites in brain
The interesting technique also could work to locate Alzheimers sites in the brain, he says. The antigen would be designed to attach to protein plaque called amyloids that haven’t folded properly — a key indication of the presence of the disease. The same iron oxide particles in a similar magnetic field should reveal pools of disease, no matter how small.
“We haven’t done it because we lack the patience to wait till laboratory mice get Alzheimer’s,” he gently jokes.
The ability to achieve iron nanoparticles of narrow size distribution, so that all particles have the same magnetic response, is one reason for the work’s success to date, says Dale. “If the iron particles nucleate slowly and then grow, there’s no catching up for the ones that nucleate later: they’ll always be smaller than the ones that nucleated earlier. So we want, and have achieved in this system, rapid nucleation and slow growth.”
The science is an interesting change for a polymer chemist used to working with materials that grow like microscopic snakes, forming slowly yet growing to the same size.
“I do a lot of different work I wouldn’t have done without outside suggestion,” says Dale. “Anyone can write a proposal to work with me; I welcome the chance to use CINT’s capabilities to complete the technical cores of outside projects that matter deeply.”
A formal process is available for interested researchers to apply to work with CINT personnel and available CINT equipment.
Federal agency approval will be required before testing the magnetic sensing technique in humans.