Fig. 1
Treatment of dihomo-γ-linolenic acid elevates 8-hydroxyoctanoic acid production and suppresses cell growth in delta-5-desaturase-KD HCA-7 cells. a Western blotting of delta-5-desaturase expression level in HCA-7 cells with or without delta-5-desaturase shRNA transfection. The expression level of delta-5-desaturase was normalized using β-actin as a loading control; b Quantification of dihomo-γ-linolenic acid/arachidonic acid ratio (Left) and 8-hydroxyoctanoic acid level (Right) from 1.0 × 106 of delta-5-desaturase-WT and delta-5-desaturase-KD HCA-7 cells after 24 h and 48 h incubation with 100 μM dihomo-γ-linolenic acid. The dashed line indicates the threshold level of 8-hydroxyoctanoic acid that can only be reached in delta-5-desaturase-KD cells; c Colony formation assay of delta-5-desaturase-WT and delta-5-desaturase-KD HCA-7 cells after exposed to 100 μM dihomo-γ-linolenic acid treatment for 48 h followed by additional 10 days incubation. The survival fractions for control groups were normalized to 100%; d Annexin V-FITC/PI staining of delta-5-desaturase-WT and delta-5-desaturase-KD HCA-7 cells after 48 h incubation with 100 μM dihomo-γ-linolenic acid. All of the data represent mean ± standard deviation with n ≥ 3. *: significant difference vs. control with p < 0.05