WNT1 and neoplasm: As the cooperation of clones was mediated by changes in the microenvironment, we were able to simulate each clone in the mixed tumor separately by modifications to the relevant node level to represent these changes; for example, increasing the activity of the Wnt1 node to represent that there is a source of paracrine Wnt1 for the Mychigh cells from the Myclow cells in the mixed tumors.