(676a) Tethered Immunolipoplex Nanoparticle (tILN) Device for Detection of Circulating Tumor Cells (CTCs) for Lung Cancer Diagnosis

Lung cancer is the leading cause of cancer deaths worldwide with a disappointing 15% overall 5-year survival rate. Circulating tumor cells (CTCs) which may constitute origin of metastasis have been identified in the peripheral blood of cancer patient. Detection of CTCs have showed great potential in cancer diagnosis and surveillance. However, because CTCs are rare, CTCs detection technique was limited by tremendous technical challenges including a lack of interlaboratory reproducibility, low numbers of isolated CTCs and loss of cell viability during processing which limiting further biological assessment.

We have recently developed a novel and simple ‘tethered ImmunoLipoplex Nanoparticle (tILN)’ method to detect CTCs in the blood of lung cancer patients. In this study, microRNA-21 (miR-21) and lung specific TTF-1 mRNA were selected as the biomarkers for lung cancer early detection. Briefly,  intracellular molecular probes, such as molecular beacons (MBs) corresponding to miR-21 and TTF-1 mRNA respectively  and cell surface marker receptors, are encapsulated and inserted respectively in liposomal nanoparticles tethered on a pretreated surface.

The tLN device as first test with non-small cell lung cancer cells (A549) .The results demonstrated A549 with high miR-21and TTF1 expression could be detected by our tLN device, suggesting possibility of CTC detection in whole peripheral blood. To further test our tLN device, prestained A549 cells were spike into health people blood sample. A549 cells on tLN showed stronger green and red fluorescence signals which are corresponding to miR-21 and TTF1 expression respectively  compared to peripheral blood mononuclear cells( PBMC), strongly indicating A549 cells were detectable in health people blood. Nanoparticles uptake is enhanced and optimized by utilizing the combined antibody and lipid interactions.  Compared to conventional method, tILNs have advantages of higher molecular beacons uptake and lower antibody and molecular beacons consumption.

Our method represents an innovative approach to characterizing the peripheral blood lung cancer. tILNs showed great potential to be an alternative CTCs detection and isolation device which may contribute to cancer diagnosis and understanding of metastasis mechanism.