MT-CO1 and colorectal cancer: Supporting the idea of RNAi within mitochondria, it was reported that transfected siRNAs are able to enter the mitochondria matrix and specifically silence their targeted mitochondrial mRNAs, downregulating the mitochondria‐encoded cytochrome c oxidase subunit 1 (MTCO1).[13,18] MTCO is a heme protein present in the mitochondria which plays an important role in the cellular respiratory chain in general,[19] as well as in colorectal cancers.[20,21]