Fig 4. Effect of ER stress inducers alone and combined effect of ER stress inducers and 1,25D₃ on expression of genes involved in lipid synthesis and transcriptional regulators of VDR in mammary epithelial cells.

MCF-7 cells were pre-incubated in DMEM with 1% FBS and with either vehicle alone (DMSO, 0.1% v/v) or 1,25D₃ (10 or 100 nM) alone for 24 h and subsequently co-incubated in DMEM with 1% FBS and with either vehicle alone (DMSO, 0.1% v/v), TG (10 nm; A, C) or TM (1 mg/mL; B, D) alone or 1,25D₃ (10 or 100 nM) together with TG (10 nM; A, C) or TM (1 μg/mL; B, D) for additional 24 h. Bars represent relative mRNA levels expressed as fold of vehicle alone and are means ± SD from three independent experiments. Bars with unlike letters are significantly different (P < 0.05). 2-factorial ANOVA classification factors: treatment (T), experiment (E), interaction (T x E). Abbreviations: CEBPA, CCAAT enhancer binding protein alpha; FASN, fatty acid synthase; HMGCR, 3-hydroxy-3-methylglutaryl-CoA reductase; LDLR, low density lipoprotein receptor; RXRA, retinoid X receptor alpha.