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G. Tarjan



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    P3.01 - Poster Session 3 - Cancer Biology (ID 147)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Biology
    • Presentations: 1
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      P3.01-017 - Nitric Oxide Adapted Lung Tumor Cells Express Tumor Stem Cell-Like Markers (ID 2367)

      09:30 - 09:30  |  Author(s): G. Tarjan

      • Abstract

      Background
      Recent studies in our laboratory show that tumor cells exposed to progressively higher concentrations of DETA-NONOate grow more aggressively than the parent cells. The currently accepted tumor stem cell model proposes that rare tumor stem cells produce both tumor cells (TCs) and rare tumor stem cells (TSCs). A number of TSC markers have been proposed, including CD antigens expression, Hoerscht 33342 exclusion, ALDH1/2 expression, and ALDH1/2 activity. In this study, we compare the TSC-like properties of parent and HNO cells. We hypothesized that human lung tumor cells adapted to high nitric oxide (HNO) levels will exhibit enhanced tumor stem cell-like properties relative to analogous cells not adapted to NO (“parent” cells).

      Methods
      The human lung adenocarcinoma cell line A549-Parent and the previously reported A549-HNO adapted cell lines were used in these studies. Immunohistochemistry was used to measure the expression of ALDH1/2 and six different CD antigens. Gene expression was measured using chip microarray analysis. FACS analysis was used to measure the population of H33342-positive and H33342-negative cells. ALDH activity was assessed using the ALDEfluor assay.

      Results
      The ALDEFLUOR assay demonstrated that ALDH activity of A549-HNO has increased compared to that of A549-parental. Relative to the A549-parental cells, A549-HNO cells showed markedly higher H33342-exclusion in the FACS analysis and greater ALDH1/2 expression in the immunostaining studies. Shocking these cells with 700 mM NO donor prior to treatment produced even more pronounced stem cell-like properties, suggesting that NO might be able to influence TCs into becoming more TSC-like. Gene chip results show that CD44, ALDH1A1, and ALDH2 are more highly expressed in A549-HNO cells than in A549-Parent cells. Cytospin results showed that ALDH1/2, CD44, and CD133 were more highly expressed in the A549-HNO cells, relative to A549-Parent cells.

      Conclusion
      The TSC markers tested in this study are consistent with the A549-HNO cells being more TSC-like than the A549-Parent cells. Having a large population of TSC-like cells would allow for improved drug screening of therapeutic candidates specifically designed to target TSCs.