To clarify the function of TSP1 in exosomes released by breast cancer cells, we established MDA-MB-231/sh-THBS1, a TSP1-knockdown MDA-MB-231 cell line and MCF7/THBS1, a TSP1 stably expressing MCF7 cell line, and prepared exosomes derived from the transfectants as well as parent breast cancer cells (Figure 4C and Figure S5). Here, THBS1 is linked to breast carcinoma.