CTC Chip Tracks Lung Cancer Cells

Armen Hareyan's picture

New technique makes it possible to identify genetic fingerprint of lung cancer cells. Circulating tumor cells (CTC) will help doctors to identify cancer cell mutations, choose targeted therapies for each patient individually, track cancer cell changes during treatment and change it if necessary.

A joint team of researchers from Massachusetts General Hospital Cancer Center and Harvard Medical School examined 27 patients with non-small-cell lung cancer. Twenty three patients in the study were found to have EGFR gene mutations. They were taken blood tests to find and examine circulating cancer cells.

Researchers used Circulating tumor cells chip technology, which is examining circulating tumor cells (CTC) in lung, pancreatic, prostate, breast and colon cancers. CTCs are the cells circulating through blood and spreading cancer to other parts of body. This cancer spread process is called metastasis, which is the main reason of why cancers are deadly. CTC chip is a business card sized chip with 80000 coded columns. Columns have antibodies on them which are identifying cancer cells in blood easily.

CTC chip technology successfully found 99% of all circulating cancer cells from blood samples and 92% of EGFR gene mutations.


This new technology is a huge step forward to individual targeted cancer treatment. Health professionals now clearly understand the importance of targeted therapies, because some patients may successfully respond to a cancer treatment, but some others may not. Using CTC chip technology they will be able to define how exactly a patient will respond to a certain treatment and if the treatment will be successful or not.

Besides, even if treatment of cancer is successful, cancer cells may adapt to the treatment and make it useless to go on with the same therapy. This technology will enable doctors to track cell gene mutations during therapy period and change it if necessary.

CTC chip technology is still in development and lots of work needs to be done to have the chip automated so that big amount of blood samples can be checked, but the innovation is already promising, because it looks at cancer source, not only at symptoms.

CTC chip is yet expensive, but researchers mention that if a patient gets proper therapy which will work for him, he will save a lot on other cancer treatments which will be useless for him.

We had earlier published on CTC Chip Discovery from the Massachusetts General Hospita writing that "A team of investigators has developed a microchip-based device that can isolate, enumerate and analyze circulating tumor cells (CTCs) from a blood sample. CTCs are viable cells from solid tumors carried in the bloodstream at a level of one in a billion cell. Because of their rarity and fragility, it has not been possible to get information from CTCs that could help clinical decision-making, but the new device - called the "CTC-chip,"- has the potential to be an invaluable tool for monitoring and guiding cancer treatment."



The interest in and the knowledge of gene expression profiling in cancer medicine has heighten since the completion of the human genome project. However, researchers have cautioned the science of gene expression profiling, in which scientists examine the genetic signature of a cell. The gene chip is a device that measures differences in gene sequence, gene expression or protein expression in biological samples. It may be used to compare gene or protein expression under different conditions, such as cells found in cancer. Hence the headlong rush to develop tests to identify molecular predisposing mechansims whose presence still does not guarantee that a drug will be effective for an individual patient. Nor can they, for any patient or even large group of patients, discriminate the potential for clinical activity among different agents of the same class. The challenge is to identify which patients the targeted treatment will be most effective. Tumors can become resistant to a targeted treatment, or the drug no longer works, even if it has previously been effective in shrinking a tumor. Drugs are combined with existing ones to target the tumor more effectively. Most cancers cannot be effectively treated with targeted drugs alone. What is needed is to measure the net effect of all processes within the cancer, acting with and against each other in real time, and test living cells actually exposed to drugs and drug combinations of interest. The key to understanding the genome is understanding how cells work. How is the cell being killed regardless of the mechanism? The core understanding is the cell, composed of hundreds of complex molecules that regulate the pathways necessary for vital cellular functions. If a targeted drug could perturb any of these pathways, it is important to examine the effects of drug combinations within the context of the cell. Both genomics and proeomics can identify potential therapeutic targets, but these targets require the determination of cellular endpoints. Sources: Eur J Clin Invest, Volume 37(suppl. 1):60, April 2007 BMJ 2007;334(suppl 1):s18 (6 January), doi:10.1136/bmj.39034.719942.94 Gregory D. Pawelski