2002; Qian et al. 2013). Furthermore, high Syntenin expression in TNBC was linked to increased proliferation and migration, whereas estrogen receptor signalling counteracted Syntenin expression in Luminal A breast cancer cells (Koo et al. 2002; Qian et al. 2013). Accordingly, the observed differences between triple‐negative 4T1 and hormone receptor‐positive MCF‐7 cells regarding the impact of Syntenin depletion on sEV composition and function appear reasonable and should be addressed in comparative studies including human TNBC cell lines such as MDA‐MB‐231 (González‐King et al. 2022). Here, ESR1 is linked to breast cancer.