Gene Network Analysis of Glucose Linked Signaling Pathways and Their Role in Human Hepatocellular Carcinoma Cell Growth and Survival in HuH7 and HepG2 Cell Lines

Figure 1

Cell density affects the rates of HepG2 and HuH7 cell growth, proliferation, and survival. (a) RTCA analysis represented by cell index (mean values ± SEM, ): (1) adhesion phase and (2) proliferative phase. (b) Flow cytometry analysis of cell cycle by propidium iodine incorporation. Graphs illustrate both cell distribution (FSC-A, SSC-A subset) and their corresponding propidium iodine incorporation for 5000 cells, 72 hr. Significant increase in Sub-G1 (dying cells) was observed in low density plated cells, that is, 5000 cells/cm² counteracted by reduced number of proliferative cells in S phase. In another way, proliferative cells were significantly reduced in high density plated cells, that is, 10000 to 20000 cells per well (mean values ± SD;Student’s -test -value, ). (c) Scepter cell count and cell size analysis of low density plated HepG2 cells (5000 cells/cm²) using 60 μm tips. Cell index was reduced after 24–48 hr and then was increased within 72 hr. Cell size distribution was different in cells plated at high (80% confluency) versus low density plated cells 72 hr after serum removal. In low density plated cells, living cells were selected in a range of 12–35 μm and smaller cells were considered as dying, dead cells, or cell fragments and thus they represent cell death. The fraction of cell death was significantly increased in low density plated cells and characterized by a significant reduction of mean size of living cells (mean values ± SD;Student’s test -value, ). (d) Phase contrast micrographs (5000 cells/cm², ×10) after 24 and 72 hours of cell culture. HepG2 cells were found to proliferate and grow in tridimensional groups.

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