As the tumor-TME interactions include oncogenic, paracrine signaling, these differences in tumor and stromal populations produce complex, re-enforcing effects; thus, differences in Igf1-expressing myeloid populations correlate with differences in mTORC1 activation in tumor cells Differences in developmental history, therefore did not produce large differences in global gene expression profile, but significantly altered the heterogeneity within tumors, producing differences that can be self-amplifying. The gene discussed is IGF1; the disease is neoplasm.