A tiny particle makes its way into the bloodstream and latches onto a newly dividing cancerous cell. The particle is specially designed to show up on a diagnostic scan, allowing doctors to easily locate the growing tumor. The particle may even have its own set of cancer-fighting drugs, which it could insert directly into the cell, avoiding the side effects of chemotherapy.
This scenario may soon be a reality thanks to the work of researchers like Chenjie Xu GS, who is the lead author of a recently published paper about a new nanoparticle he and other researchers created. Xu, a student in Professor of Chemistry Shouheng Sun's lab, collaborated on the paper with Baodui Wang, a visiting scientist at Brown. The nanoparticle they describe was developed with two parts: one containing a protein antibody that attaches to a cancerous cell and the other with cisplatin, a common chemotherapy drug.
Though both the antibody and the drug are commonly used separately in cancer treatment, this novel approach combines the two. The combination uses the specificity of the antibody and the potency of the drug to directly attack cancerous cells without harming healthy ones.
Current treatments use the antibody to inhibit the growth of tumor cells, but the patient must be given an antibody injection on an almost weekly basis, Xu said, adding that the new treatment inhibits the growth of the cell.
But, he said, "you want the tumor to shrink, not just stop growth." That's where Cisplatin comes in.
The drug, commonly used in chemotherapy, shrinks tumors, but is problematic because it is nonspecific. Usually it is injected into the body in large quantities and harms both healthy and cancerous cells. The new technique will allow doctors to release Cisplatin directly at the site of the tumor, avoiding the general side effects of chemotherapy.
Another advantage of the new particle is its clear visibility on diagnostic scans. The core of the particle is made of iron and gold, which give it a distinct magnetic signature, making it easy to identify with magnetic resonance imaging and computed tomography scans.
A "tumor cell used to be a healthy cell," Xu said, noting that in the early stages of tumor development it is difficult to distinguish cancerous tissue from healthy tissue through basic imaging alone.
Since early detection of cancer can vastly improve the efficacy of treatment, having better ways to detect cancerous cells early on can be very valuable, Xu said. The particle will show up on both MRI and CT scans, giving more precise information about the state of a tumor faster, Xu said.
Currently, the particles have not left the test-tube stage of development, but Xu said animal testing, in collaboration with Rhode Island Hospital, is scheduled to begin shortly. The researchers will first test whether the particles show up on diagnostic scans, and then examine how effective the particle is at administering the drug.
The particle will not be tested on humans for several years, Xu said.
Later, other antibodies and drugs could be substituted into the basic particle to allow different medications to be administered to other types of cells, he said.
The lab has received calls from several news stations and has been contacted by science-business companies about the new particle.
"We publish a lot of papers every year, this is the first time people are excited," Xu said. "This means our work is important."