Tracking Functional Tumor Cell Subpopulations of Malignant Glioma by Phasor Fluorescence Lifetime Imaging Microscopy of NADH

Cancers

Eric R. Siegel¹  Michelle A. Digman²  Hongtao Chen²  Andrew L. Trinh²  Zhenzhi Li³  Mark E. Linskey³  Yuanjie Hu³  Yi-Hong Zhou³  Ping H. Wang⁴  Yumay Chen⁴ 

[1] Department of Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA;Laboratory for Fluorescence Dynamics and Department of Biomedical Engineering, University of California, Irvine, CA 92697, USA;UC Irvine Brain Tumor Laboratory and Department of Surgery, University of California, Irvine, CA 92697, USA;UC Irvine Diabetes Center and Department of Medicine, University of California, Irvine, CA 92697, USA;

关键词: Reduced nicotinamide adenine dinucleotide (NADH);    cellular bioenergetics;    malignant glioma;    tumor cell subpopulation;    fluorescence lifetime imaging microscopy (FLIM);    stem-like tumor-initiating cells;    tumor mass cells;    intra-tumoral heterogeneity;   

DOI  :  10.3390/cancers9120168

来源: DOAJ

【 摘 要 】

Intra-tumoral heterogeneity is associated with therapeutic resistance of cancer and there exists a need to non-invasively identify functional tumor subpopulations responsible for tumor recurrence. Reduced nicotinamide adenine dinucleotide (NADH) is a metabolic coenzyme essential in cellular respiration. Fluorescence lifetime imaging microscopy (FLIM) of NADH has been demonstrated to be a powerful label-free indicator for inferring metabolic states of living cells. Using FLIM, we identified a significant shift towards longer NADH fluorescence lifetimes, suggesting an increase in the fraction of protein-bound NADH, in the invasive stem-like tumor-initiating cell (STIC) subpopulation relative to the tumor mass-forming cell (TMC) subpopulation of malignant gliomas. By applying our previously studied model to transition glioma from a majority of STIC to a majority of TMC in serum-adherent culture conditions following serial passages, we compared changes in NADH states, cellular respirations (oxidative phosphorylation and glycolysis), EGFR expression, and cell-growth speed over passages. We identified a significant positive correlation between free-NADH fraction and cell growth, which was related to an increase of TMC fraction. In comparison, the increase of EGFR and cellular respirations preceded all these changes. In conclusion, FLIM of NADH provides a non-invasive method to monitor the dynamics of tumor heterogeneity before and after treatment.

【 授权许可】

Unknown