APC and neoplasm: First, the tumorigenic phenotype observed in pre-clinical models is primarily characterized by an increase in tumor number rather than an increase in tumor size.25 Additionally, in CRC cases harboring the pks+ E. coli mutational signature, the highest proportion of mutations matching the pks motif (AAWWTT) occur within the APC gene (5.3%),5 the most commonly mutated gene in CRC patients.