GRN and cancer: It is asserted in the latter reference that cell surface-associated endogenous GRP78 is a determinant of cancer stemness development, which can be reversed by the GRP78 interactome protein, progranulin: Being expressed on the cancer cell surface, GRP78 is conducive to cancer stemness, but interactions of GRP78 with progranulin, if they occur, retain a non-stem cancer cell phenotype [245].