TGFB1 and breast cancer: Most interestingly, our general kinetic model of genes regulation mechanisms at the single cell level could help one to understand some macroscopic physiological phenomena at the level of whole breast cancer cell population, such as the phenotypic equilibrium in subpopulations of breast cancer lines25, the “TGF-β paradox” in tumor therapy31–41, the five clinical subtypes of breast cancer cells42, 43, and the effects of transient TGF-β on cancer metastasis44.