It is already well known that a stiff extracellular matrix favors tumor and stromal cell migration and invasion, but what pertains to the topic of this review is that exposure to an oscillatory strain induced an increase in small EVs production, particularly of PD-L1 + small EVs, by TNBC cells, concomitantly to a rise in the number of MDSCs and M2 macrophages, thus resulting in a highly aggressive disease supported by an immunosuppressing TME [26, 62]. Here, CD274 is linked to neoplasm.