(523b) Biosensor Incorporating Cell Barrier Architectures For Screening Cancer

According to American Cancer Society 559,650 deaths are expected from cancer making it the second most death causing disease after heart diseases. In most cases, detection of cancer at the early stages is not possible as it involves complicated invasive procedures. In the absence of a quick screening tool, many individuals are diagnosed in the latter stages of the disease thereby reducing the chance of successful therapy. It is a known fact that early screening of cancer can reduce cancer death by nearly 50%. Screening can not only detect cancer at early stages but can also identify an individual showing an inclination towards developing cancer. Thus at present there is an urgent need for a quick screening tool for cancer. Research efforts have demonstrated that higher concentrations of cytokines like VEGF, HGF, bFGF, TNF-alpha, etc are released in the blood of cancer patients as compared to healthy individuals. These angiogenic molecules are also known to modulate the permeability of endothelial cells. A cell based biosensor has been developed in our laboratory. This sensor consists of a confluent monolayer of human umbilical vein endothelial cells (HUVECs) seeded on the surface of an asymmetric cellulose triacetate (CTA) membrane of ion selective electrode (ISE). Earlier studies demonstrated that upon confluent monolayer formation, complete inhibition of ion transport occurs across the membrane resulting in reduced response. Exposing the sensor to permeability modifying agents results in a concentration dependant response from the sensor. The present study focused on applying the biosensor as a screening tool for cancer. For this purpose, the biosensor was exposed to the above mentioned cytokines, individually and in combinations, at concentrations observed in the blood of cancer patients and compared to the responses obtained when exposing the sensor to the cytokines at concentrations found in healthy patients. The study demonstrates the ability of the sensor to differentiate between these concentrations of cytokines when measuring both individual and combinations. Currently, multiplexed ELISA is capable of simultaneously detecting a number of individual growth factors. However, since during the early stages of cancer, individual concentrations of these factors are low, detection using ELISA poses a difficult problem. Since, the biosensor can measure not only individual cytokines but also combinations of them; we hypothesize that this biosensor will be able to detect cancer at the early stages. Present studies are directed towards exposing the biosensor to the serum of healthy individuals and cancer patients and measuring the responses. These results will also be discussed.