A genetic engineering study of the NK-92MI using lentiviral transduction to express BCL-2 siRNA (siBCL-2), which is enriched in NEVs and successfully enhanced tumor-killing ability by inhibiting overexpression of BCL-2 in breast cancer (Figures 1F, 4D) (Kaban et al., 2021). The gene discussed is BCL2; the disease is breast cancer.