Other mitochondrial metabolic and dynamic effects of 1,25(OH)2D include the suppression of the heme biosynthesis pathway by way of UROS, which is part of the catalytic steps of porphyrin biosynthesis and associated with cancer when heme production is left unchecked.(42) Furthermore, mitofusion 1 (MFN1) was downregulated after 1,25(OH)2D treatment that mediates mitochondrial fusion, suggesting reduced mitochondrial networks, ATP production, and OXPHOS. This evidence concerns the gene MFN1 and cancer.