Characterization of the Cancer Stem Cell Inhibitor

Accumulating evidence has indicated that in many cancer types including lung, contain a subpopulation of cells that exhibit stem-like cell properties thus generally termed lung cancer stem cells (LCSCs). LCSCs are characterized by their resistance against radiation and cytotoxic chemotherapy and implicated as a key contributing factor for therapy failure and disease relapse. Thus selective elimination of these LCSCs may lead to a more effective and perhaps curative therapeutic strategy. Here we propose to utilize a Connectivity Map (CMAP)-based platform to screen known agents whose potential “off-targeting” effect could selectively eliminate LCSCs. Since all the compounds within CMAP database are structurally defined and many of them are clinically proven drugs, repurposing these compounds (or synthesis of their derivatives) as clinical anti-LCSC agents will be significantly more cost and time-effective than developing a brand new drug. The following specific aims are proposed to accomplish our overall goal. (1) Isolation and characterization of LCSCs. Using flowcytometric method and CD markers, we will isolate LCSCs from different lung cell lines and assay for the acquisition/maintenance of “stemness”, metastatic switch and drug-resistance. Importantly, these data will serve to improve LCSC gene signature inputs for CMAP-based anti-LCSC agent searching algorithms. (2) In silico screening of potential anti-LCSC lead agents using LCSC gene signatures and examining their biological properties. LCSC gene signatures obtained from lung cancer cell lines (established in aim 1) will serve as our new input for querying CMAP database. Initially, we used embryonic stem cell (ESC) and several lung cancer adenoma signatures to query CMAP database and identified Antimycin A (AMA) as one of the potential candidates against putative LCSCs. AMA-mediated anti-LCSC effects will be examined and validated both in vitro and in vivo. Data obtained from this aim will be fed back into CMAP and further refine our search algorithms. (3) Preclinical evaluation of AMA as anti-LCSC agent. AMA and other top-ranked candidates will be selected as lead compounds for chemical modification. Preclinical evaluation including pharmacokinetics/pharmacodynamics properties and safety of these candidate drugs will be performed. Technology transfer or patents of these candidate drugs will be prepared and filed. We believe that our platform represents a shortcut for identifying and pipelining urgently needed anti-LCSC agents. The successful completion of this project may lead to accelerated clinical trials of these agents for treating drug-resistant lung cancer patients.