Therefore, we analyzed TCGA transcriptomic data sets of TETs, breast and lung cancers (CBioPortal, http://www.cbioportal.org/ accessed on 9 March 2022) for the expression of the two key synthesizing enzymes (choline acetyltransferase [CHAT] and carnitine acetyltransferase [CRAT]), the key degrading enzyme (acetylcholine esterase [ACHE]) and several transporters (including the organic cation transporters, OCT1-3 [SLC22A1-3]) but did not find a unique RNA expression pattern that could easily explain the higher levels in TETs (Figure S5) [58]. Here, SLC22A13 is linked to lung cancer.