High-throughput small RNA sequencing, identification of differentially expressed miRNAs, and prediction of target genes and networks in wt and BAG-1KO MCF-7 cells showed that PI3K/Akt signaling, ECM-receptor interaction, proteoglycans in cancer, and TGF-β signaling pathways were highly enriched in BAG-1KO samples compared to wt samples. This evidence concerns the gene PIK3CA and cancer.