Mechanistic Investigation on the Regulation of FABP1 by the IL-6/miR-603 Signaling in the Pathogenesis of Hepatocellular Carcinoma

Figure 2

Interactions between FABP1 and FFA. (a) FABP1 increases the uptake of FFA by Huh-7 cells. The lipid content in the cells increased significantly after adding FFA in the culture medium compared with the control group (NC+FFA). Red color represents the lipid content. When the cells were transfected with the FABP1 overexpression lentivirus and then cultured with FFA (FABP1+FFA), the lipid content increased in the cells, while lipid content decreased significantly after FABP1 RNA interference (RNAi) transfection (FABP1-RNAi+FFA). The lipid was stained in red; 10 randomly selected fields were checked under an inverted microscope, . (b) Quantification of the content of lipid in the cells. The relative content of lipid was measured by spectrophotometer at 500 nm (fold change from NC). Data are expressed as the , in each group. . (c) FFA increases the uptake of FABP1 by Huh-7 cells. Expression of the FABP1 protein in Huh-7 cells after FFA treatment. Huh-7 cells were induced by FFA at different concentrations (0, 0.5, 1.0, 2.0, and 4.0 mM), and the expression of FABP1 was detected at different induction concentrations by Western blot. GAPDH was used as the internal loading control. (d, f) Colocalization of FABP1 with Golgi apparatus and lysosome. Cells were transfected with FABP1-EGFP vector (green) alone or induced with FFA after (FABP1-EGFP+FFA) transfection, and then, the cells were stained with Golgi-Tracker or Lyso-Tracker. The Golgi apparatus or lysosome was stained in red, and the nuclear was stained by Hoechst in blue. Cells of 10 randomly selected fields were observed by a confocal microscopy (Olympus, Tokyo, Japan), and the fluorescence intensity was calculated by ImageJ software. . (e, g) Quantification of the green fluorescence intensity in the cells and the bar graph was drawn. Data are expressed as the , in each group. . Arbitrary units (AU).

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