Table 2.

Different models of multiple myeloma (MM) oncogenesis according to their initiating and promoting events.

Model of MM Oncogenesis	Standard	Unifying	Extended and Permissive	TiDiS
Initiation level	Cell	Cell	Cell	Tissue
Initiating event	Genetics	Genetics	Genetics	Microenvironment
Promoting event		Epigenetics	Epigenetics + microenvironment	Genetics + epigenetics
Supporting features of MM cells and their precursors	Genotype	Morphotype, phenotype, proliferation index	Extended phenotype to bones (LBL, generalized bone loss)	Abnormal cellular interactions within bone