The MTT assay results indicated that SZU-101 had no direct effect on EL4 tumour cells (Figure 2B), which was in line with others’ findings of another TLR7 agonist, imiquimod, on acute myeloid leukaemia (AML) cells, whereas the TLR7/8 agonist R848 may lead to terminal differentiation and suppressed cell proliferation in AML [22]. Here, TLR7 is linked to neoplasm.