TLR7 and cancer: The study confirmed that the FMR1-AS1 exosomes were secreted from cancer stem-like cells (CSCs) of ESCC, which transferred stemness phenotypes to recipient non-CSCs in the TME through the mechanism of activating toll-like receptor 7-nuclear factor κ B (TLR7-NFκB) signaling, upregulating the c-Myc level in recipient cells.