Abstract
Objectives
Aims of this study were to investigate the effect of HF on anchorage-independent tumor spheroid formation and its’ working mechanisms of lung malignant tumor cells.
Methods
Human NSCLC cells A549 were cultured in control (C) medium (2.2 μM folic acid) or HF medium (10, 30, 50 μM folic acid) for 4 days. Cells were harvested to explore the self-renewal capacity of cancer cells by observing the anchorage-independent tumor spheroid formation. Meanwhile, the L-lactate assay were conducted to evaluate the lactate-generating state and the cell protein extract for the western blotting analysis to realize expression of energy metabolism related proteins in cells.
Results
The results showed that numbers of tumor spheroids in HF group were significantly higher than the control group. Besides, compared to C group, HF50 group showed significantly reduced lactate release into medium with highly accumulation in cellular lactate levels. The glycolytic-related protein expression of hexokinase II (HKII), lactate dehydrogenase (LDH) were increased and glucose transporter 1 (GLUT1), pyruvate dehydrogenase (PDH) were decreased in HF group. The signaling-related protein expression of insulin receptor substract-1 (IRS-1), hypoxia-inducible factor-1 alpha (HIF-1α) were increased and PI3 kinase (PI3K), AMP-activated protein kinase (AMPK) were decreased in HF group.
Conclusions
Collectively, HF supplementation may reprogram glycolytic metabolism and increase anchorage-independent tumor spheroids formation to mediate malignant progress of NSCLC.
Funding Sources
Ministry of Science and Technology, Taiwan, R.O.C.
Core-shell hydrogel beads with extracellular matrix for tumor spheroid formation