We used TargetScan, an miRNA target prediction algorithm, to discover the downstream targets of miR-20a in the autophagy pathway. Several autophagy related genes, including BECN1, ATG16L1 and SQSTM1 were identified as putative targets. To validate, we performed qPCR and immunoblotting analysis. Overexpression of miR-20a markedly reduced the transcript abundance of BECN1, ATG16L1 and SQSTM1 in both MDA-MB-231 and MCF7 cells (Figures 2a and c). Immunoblotting revealed that miR-20a suppressed BECN1, ATG16L1 and SQSTM1 protein expression in both cells (Figures 2b and d and Supplementary Figure S4). We were also interested to know whether knockdown of endogenous miR-20a would affect target genes expression. LNA-modified miR-20a inhibitor (LNA-20a) efficiently suppressed endogenous miR-20 expression (Supplementary Figure S3c). LNA-20a moderately increased the amounts of BECN1, ATG16L1 and SQSTM1 in both MDA-MB-231 and MCF7 cells (Figures 2b and d and Supplementary Figure S4).