Fig. 1.

Optimization of the oxygen level in in vitro culturing of MEC-1 cells based on gene expression profiling. Heat maps show the gene expression (TaqMan-based qRT-PCR) profiles of MEC-1 cells (control (Ctrl) and miR-155 deficient clone #48 (miR-155^–/–)) in normoxia vs hypoxia. A Heat map shows changes (as Fold Change, FC) in the mRNA/miRNA expression level in different hypoxia conditions. Hypoxia conditions were set as follows: 0.2, 1 and 5% O₂ for a period of 24 h. B Heat map shows changes in the mRNA/miRNA expression level in 1% O₂ (hypoxia) in MEC-1 ctrl and miR-155 ^–/– cells in different time-periods (24 h–120 h). C Heat map summarizes the expression level of selected hypoxia-related genes measured in the final hypoxia and time-period settings in MEC-1 cells, 1% and 24 h–48 h, respectively. In all 3 heat maps, the expression data were normalized to the expression level measured in normoxia and set as 1. The gene expression in all heat maps is shown as fold change (FC) and its intensity expresses the color scale next to each heat map