It seems that everyday there is something new about cancer. I am definitely astonished by all the different types of devices that are used to detect cancer cells in different parts of our bodies. Just to name a couple, there are Positron Emission Tomography (PET), lasers, electronic nose, and Canon’s advanced breast scanner detector. But most recently, there has been one device that has impressed many doctors and scientists.
Although it has not been given a name yet, this device, developed by a Harvard bioengineer (Mehmet Toner) and an MIT aeronautical engineer (Brian Wardle), can be very promising to efficiently detect malignant tumor cells circulating in our veins, as well as HIV, hepatitis B and C, and the human papilloma virus. However, we need to take into account that metastasis is highly inefficient. Many tumor cells might enter the bloodstream every day, but only a small portion ever succeeds in colonizing another tissue. Personally, I believe that the purpose of this device is only to detect tumor cells in the bloodstream; it does not confirms the formation of secondary tumors, but it is definitely helpful tool to know when a tumor has reached its malignant state, and to maybe be able to regulate cell proliferation with drugs such as Avastin. According to the article that I found, Small, a peer-reviewed interdisciplinary journal, published the study on March 17th, 2011, called “Nanoporous Elements in Microfluidics for Multiscale Manipulation of Bioparticles,” but unfortunately I did not have access to analyze the study, therefore, this blog entry is based on information found in the article that I read. The microfluidic device is about the size of a dime, and it is expected that in future years it could be developed at low cost, in order to provide doctors in developing countries with efficient and inexpensive equipment to detect cancer and other viruses. The device was improved from a previous device, which failed because of its lack of precision to detect a larger number of tumor cells in the bloodstream through the use of solid silicon posts coated with tumor-selective antibodies. Toner remodeled his device by replacing the inefficient silicon posts with porous made up by carbon nanotubes that would possibly carry tumor-selective antibodies. Carbon nanotubes have unique properties such as high surface area, hollow cavities, and excellent mechanical and electrical properties.
This device is a great invention for tumor metastasis detection as supported by Dr. Wardle, who reported, “Of all deaths from cancer, 90 percent are not the result of cancer at the primary site,” but instead these deaths occurred because of “the tumors that spread from the original site.” Additionally, the porous of these devices are made of about 1 percent nanotubes and 99 percent air or free space, which allows plenty of fluid to go through, yet is very effective at trapping target cells. I believe that this device seems to be really good and efficient, but I definitely think that more studies should be done before it is used by hospitals to analyze the possible sources of error. I still wonder if this device's tumor-selective antibodies are designed to recognize all types of tumor cells, or if maybe some other component in the blood stream could disrupt their function?
If you guys have any further interest in nanotubes, I would recommend this article, which is about 6 years old, but still have some interesting information about carbon nanotubes and some of their biological functions: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1187972/
Sources:
ScienceDaily. "Catching cancer with carbon nanotubes: New device to test blood can spot cancer cells, HIV on the fly." Science Daily: News & Articles in Science, Health, Environment & Technology. N.p., 30 Mar. 2011. Web. 1 June 2011. .
Grace D. Chen, Fabio Fachin, Marta Fernandez-Suarez, Brian L. Wardle, Mehmet Toner. Nanoporous Elements in Microfluidics for Multiscale Manipulation of Bioparticles. Small, 2011; DOI: 10.1002/smll.201002076
Silly, yet somewhat informative animation:
