For people facing cancer, the decision of which treatment to use is too often made blindly and with no true knowledge on whether the specific treatment is the best one for a certain individual. Microfluidics chips are aimed to solve just this problem. The small silicon-etched chip is fitted with microscopic columns which act as test tubes in which cancerous cells and chemicals can be mixed and evaluated. The chip is able to detect small changes in gene expression, not only a gene mutation, which had been a problem for scientists in the past.
How does this chip work? Most carcinomas (cancer in the epithelial tissue of the skin or in the lining of internal organs) “shed” malignant cells which then enter the blood stream and can continue to grow in a new area. The cancerous cells in the blood, CTC’s (cancerous tumor cells), are what the chip picks up. The microposts of the cell are coated with antibodies to the epithelial cell adhesion molecule (EpCAM) which is present in almost all carcinoma cells but not on the surface of normal blood cells. The chip can therefore pick up only the cancerous cells which was in itself a difficult job before because the percentage of CTC’s in blood can be less than one in a million (particularly with early-staged patients in which the tumors may have not fully spread and then the CTC number will be even smaller). However, the chip has been able to find cancer cells as rare as 1 in a million; about 100 times better than commercial fluidic devices. Also, with the accustom procedure of having a large sample of blood drawn and add antibody-coated microbeads to find the cancer cells, the sample is more damaged than when the CTC chip retrieves the cancer cells.
The data obtained through the chips will allow for more precise treatments based on the molecular characteristics of the malignant cells (for example, whether certain hormones or genetic mutations are present). The chip can also help patients whose cancer cells may have mutated to resist a certain drug or have metastasized. In certain cancers, like lung cancer, the necessary biopsy to examine the cancer cells cause a risk of blood loss, infection, or even a collapse lung. However, the studies by a group in
Sites used: http://www.scientificamerican.com/article.cfm?id=a-chip-against-cancer , http://www.technologyreview.com/biomedicine/23551/page1/
1 comment:
Mary, this is a truly amazing stepping stone for medical proffesionals treating people with cancer. These chips would be able to save so many lives by detecting cancer at an early stage and also help protect those with cancer at an earlier stage. I found out that these chips are not only beneficial in discovering cancer cells, but they can also be used for various other purposes, ranging from ink jet printers to labs-on-a-chip for fast and cheap DNA sequencing. Psychiatrists have been able to use these chips to chemically and electrically express DNA sequences. This allows them to predict how a person's body will metabolize about 25 percent of drugs on the market! The chip tests for mutations in genes of each person that break down drugs, and enables doctors to see how effective certain drugs are. Obviously, microfluidic chips are an increasingly important emerging element of medical treatment. It is amazing to see the medical stages that the human race has reached with the use of technology!
http://www.sciencedaily.com/videos/2006/0805-gene_chip_for_personalized_meds.htm
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