SDC1 and cancer: Recent studies have suggested that SDC1 (a cell surface proteoglycan syndecan-1) controls the migration of MDA-MB-231 TNBC cells via a mechanism dependent on TGF-β1-SMAD signaling and E-cadherin [161], while a transcription factor RUNX2 (runt-related transcription factor 2) influences chemoresistance by modulating cancer cell stemness through its direct interaction with TGF-β [162].