Since no specific inhibitor for p70S6K is currently available, we prompted to use three different RPS6KB1 siRNAs for inhibition of p70S6K in cell lines with high-level amplification and overexpression of RPS6KB1. Altogether, 109 and 173 genes were differentially expressed in two RPS6KB1-suppressed breast cancer cell lines, including 68 genes of which expression was altered in both cell lines and 17 genes that overlapped with genes differentially expressed after the small molecule inhibitor treatments. Here, RPS6KB1 is linked to breast carcinoma.