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Fig. 3 MITF† directly regulates a redox program in melanoma in vivo. (A) Correlation of downregulated genes after MITF knockdown that are annotated with regulation of cellular redox levels across 61 melanoma cell lines in the CCLE microarray dataset. (Total available melanoma cell lines for microarray data at the Depmap portal: 61) MITF occupies promoter or enhancer regions of most of these genes (defined as MITF ChIP peaks within ± 20 kb of a transcription start site (TSS), indicated with bold) based on a publicly available MITF ChIP-sequencing dataset and a ChIP-ChIP dataset. The genes displayed in panel a were used to define an MITF-driven redox program, which was scored using the singscore algorithm in human patient tumor samples from TCGA. Singscore algorithm defined MITF-driven redox program significantly correlates with MITF mRNA levels across melanoma cell lines (CCLE, B, p < 0.001), and 474 human melanoma samples (TCGA, C, p < 0.0001). (D) mitfa:BRAFV600E;p53-/-;mitfa-/-;crestin:EGFP zebrafish were injected at the single cell stage with a MiniCoopR plasmid that rescues melanocytes and expresses human MITF under control of the zebrafish mitfa promoter (mcr:MITF) or with the same plasmid without the human MITF expression cassette (mcr:Empty), along with a plasmid expressing the mCherry marker from the zebrafish mitfa promoter (mitf:mCherry). (E) HPLC-based redox measurements in melanoma tumors from zebrafish re-expressing human MITF (mcr:MITF) or control plasmid (mcr:Empty) at 2 weeks post-fertilization show decreased 8-oxoG levels in MITF overexpressing zebrafish tumors. The mcr_Empty vectors was used as a negative control. Values represent the mean ± SEM. **p < 0.01. Abbreviation: MITF microphthalmia-associated transcription factor, CCLE cancer cell line encyclopedia, TCGA the cancer genome atlas, 8- oxo-G: 8-Dihydro- 8. oxoguanine.