Effects of all-trans-retinoic acid incorporated into low-density lipoprotein on invasive properties of multidrug-resistant MCF-7 spheroids.

Cultured cells grown as spheroids provide an in vitro model that is closer to an in vivo tumour than conventional monolayer techniques. Previous work from our laboratory has demonstrated that spheroids formed from multidrug-resistant MCF-7 cells exhibit invasive characteristics which were not present in their sensitive counterparts. The treatment of these spheroids by all-trans-retinoic acid (ATRA), a potent inducer of in vitro and in vivo differentiation, decreases their proteolytic activity and ability to invade Matrigel-coated filters.

[Detection of metastatic activity of the MCF-7 multidrug resistant cell line cultured in spheroids].

The occurrence of solid tumors spreading through the body is a major concern for the clinicians. Moreover, in numerous cases, metastases exhibit a multidrug resistant (MDR) pattern. This dual characteristic still remains supported by few biological explanations.