Although all the agents we used were validated in previous studies, we must acknowledge the possibility of off-target effects on other muscarinic receptor subtypes, e.g., M4R. We also acknowledge the possibility that field effects in ‘normal’ tissue adjacent to colon cancer cells may impact the analysis of muscarinic receptor expression depicted in Figure 1; that is, muscarinic receptor expression may be even lower in normal tissue more distant from the site of cancer. The gene discussed is CHRM4; the disease is cancer.