Table 1.
Microarray results
| Microarray Analyses | Number of detected genes | Number of genes up/down- regulated (>1.5 fold change ) | Number of genes significantly up/ down- regulated (pvalue < 0.05) | % of genes altered out of detected spots |
|---|---|---|---|---|
| CTRL 2 vs. CTRL 1 | 23425 | 970 | 5 | 0.02% |
| NB vs. CTRL 1 | 33312 | 1036 | 13 | 0.04% |
| NB-DL vs. CTRL 1 | 23962 | 1773 | 344 | 1.44% |
| NB-DA vs. CTRL 2 | 22892 | 2079 | 428 | 1.87% |
| Pristine CeO2 vs. CTRL 3 | 33023 | 6020 | 1643 | 4.98% |
| H2O2 vs. CTRL 3 | 28900 | 14651 | 9307 | 32.2% |
Caco-2 cells were cultured and differentiated for 21 days. The cells were exposed for 72 h to 21.25 μg/mL CeO2 NPs, surface-treated or degraded (n = 2). Pristine CeO2 NPs at the same concentration and H2O2 (20 μM) were used as positive controls. After mRNA extraction, labeled cDNA (Cy3) was hybridized (n = 4) to an Agilent oligomicroarray (4 × 44,000 probes). The number of genes detected above the signal threshold was compared for each type of NP versus their own control. From these remaining spots, we selected those with fluorescence ratios (representing NP-treated samples versus untreated samples) above 1.5-fold change. Out of these spots, we selected those satisfying Benjamini-Hochberg multiple testing corrections. At the end of this analysis, we obtained lists of genes that were significantly induced or repressed after exposure to NPs.