Healthy epithelial colon cells influence the growth of colorectal cancer cells. Soluble factors from the healthy microenvironment cells modulate gene expression. The drug NAMI-A is imidazolium trans-imidazoledimethylsulfoxidetetrachloro ruthenate. NAMI-A counteracts the effects of the microenvironment on gene expression. Gene expression control by NAMI-A supports its inhibition of tumour cell migration.