HCAR1 and brain neoplasm: Staining for MCT1 and HCAR1 in sections of zebrafish brain tumors revealed an increase in the number of both MCT1+ and HCAR1+ cells (Figure 6D), whereas qPCR analysis of the mRNA expressions of mct1 and hcar1 revealed a significant increase in the expression for mct1 in adult tumors compared to the control brain and a significant increase in the expression of hcar1 in both adult brain tumors and in 5-dpf larvae expressing oncogenic RAS (Figure 6E).