Unicellular drug-resistant models have been critical in elucidating intrinsic drug-resistant
mechanisms; however, these models do not consider resistance mechanisms that may be
elicited by extrinsic influences such as the tumor microenvironment. We propose that
specific niches within the tumor microenvironment may provide a sanctuary for
subpopulations of tumor cells to evade or circumvent drug-induced death and that this may
represent a form of de novo drug resistance. We have found that elements of the bone …