University of California, Los Angeles (UCLA) researchers have hit a major milestone in cancer research. A method has been improved for capturing and analyzing cancer cells that break away from patients’ tumors and circulate in the blood.
With improvements to a device called NanoVelcro, even single cancer cells can be accurately detected and safely isolated from patient blood samples for continuous analysis, according to a new study published in the peer-reviewed journal Angewandte Chemie and is featured on the cover of the journal's March 2013 print issue.
For a cancer patient, when primary cancer cells called circulating tumor cells (CTCs) break away from a tumor and move through the body via the blood supply, it’s among the worst possible news.
That’s how cells “metastasize” or spread from one tumor to other parts of the body in the process of forming new cancer areas in the patient.
But these traveling cells can provide doctors with critical information about the cancer type, the characteristics of each individual cancer, and its possible progression when they are isolated early from the patient’s blood over the course of the disease.
Doctors can also tell from CTCs how to tailor a personalized treatment approach for each patient rather than a "one-size" regimen that may not be as effective.
That’s the beauty of the NanoVelcro chip, a nearly microscopic device developed by Crump Institute for Molecular Imaging and UCLA’s Jonsson Comprehensive Cancer Center.
When blood is passed through the tiny chip, it encounters hair-like nanofibers coated with antibodies from the immune system that exactly match proteins on the surface of cancer cells. These proteins act like tiny Velcro, trapping CTCs and isolating them for further studies.
Think of the process as a "liquid biopsy", said lead scientist and nanotechnology pioneer Hsian-Rong Tseng, an associate professor of molecular and medical pharmacology at the Crump Institute for Molecular Imaging, and a member of UCLA's California NanoSystems Institute and Jonsson Comprehensive Cancer Center.
Tseng's team reported that now that they have improved the NanoVelcro chip by replacing its original non-transparent silicon nanowire substrate with a new type of transparent polymer nanofiber-deposited substrate. This allows the device's nanowires to better "grab" cancer cells as blood passes by them.
"We now can not only capture cancer cells from blood with high efficiency but also hand-pick single CTCs for in-depth characterization to provide crucial information that helps doctors make better decisions," he said.
The team has been testing the improved chip on patients' blood that contains circulating melanoma cancer cells, the most deadly type of skin cancer which is prone to spreading quickly inside the body.
When researchers capture a single melanoma cancer cell they can target a specific mutation found in 60 percent of melanoma patients.
The target area, inside the cancer cell’s protein, is susceptible to drugs that inhibit the mutation by slowing — and often reversing — the growth of melanoma tumors. This is known as BRAF-inhibitor therapy.
"With this technology, we are getting closer to the goal of a widely clinically applicable liquid biopsy, where we can sample cancer cells by a simple blood draw and understand the genes that allow them to grow," Dr. Antoni Ribas, a hematology–oncology professor of medicine and Jonsson Cancer Center member, and a key collaborator in the study said in a news release.
Lynette Summerill is an award-winning writer and Scuba enthusiast who lives in San Diego with her husband and two beach loving dogs. In addition to writing about cancer-related issues for EmpowHER, her work has been seen in publications around the world.
Sources:
Shuang Hou, Libo Zhao, Qinglin Shen, Juehua Yu, Charles Ng, Xiangju Kong, Dongxia Wu, Min Song, Xiaohong Shi, Xiaochun Xu, Wei-Han OuYang, Rongxian He, Xing-Zhong Zhao, Tom Lee, F. Charles Brunicardi, Mitch André Garcia, Antoni Ribas, Roger S. Lo, Hsian-Rong Tseng. Polymer Nanofiber-Embedded Microchips for Detection, Isolation, and Molecular Analysis of Single Circulating Melanoma Cells. Angewandte Chemie International Edition, 2012; DOI: 10.1002/anie.201208452
and
UCLA researchers further refine 'NanoVelcro' device to grab single cancer cells from blood. Shaun Mason, UCLA Newsroom. 22 Feb. 2013. Access online at: http://newsroom.ucla.edu/portal/ucla/ucla-researchers-further-improve-243495.aspx
Reviewed March 5, 2013
by MIchele Blacksberg RN
Edited by Jody Smith