| Cancer is the number one killer disease in the world and lung cancer leads to the highest number of deaths annually. About 85% of lung cancer is Non Small Cell Lung Cancer (NSCLC) and is diagnosed at a later stage. Despite many decades of work to improve lung cancer diagnosis, there is a lack in effective early diagnostic tools. The routine biopsy approach is unable to monitor primary tumors and its evolution. The liquid biopsy approach to study the molecular properties of the circulating tumor cells can help in better monitoring of the disease progression, thereby improving survival among NSCLC patients.;The goal of this study is to establish a promising panel of RNA biomarkers of circulating tumor cells (CTCs) in NSCLC patients. This study will identify the roles of specific genes: N-acetylgalactosaminyltransferase (GALNACT) and Melanoma-associated Antigen-3 (MAGEA3), in CTCs, as biomarkers for NSCLC, by their expression profile. Since CTC are very low in number in the blood of cancer patients (less than 10 cells per 10 ml of blood), we worked towards an assay which can assess the sensitivity and specificity of the markers. For this, we identified six NSCLC cell lines and established a range of expression of the selected gene markers for each type against a background of 1 million blood cells. Three out of the six cell lines were selected based on their expression for the markers in less than 40 cycles, for "limiting cell dilution" analysis beginning with cell numbers of 10000, 1000, 500 and then we went down to 100, 50 and 25 cells for the cell lines to determine the minimum cell numbers required to still detect the selected markers. We established the consistency of the expression profile in the genes of interest with decreasing cell number and thus concluded that it will be possible to detect these biomarkers in CTCs of NSCLC patients. |
