In HT1080, SK-LMS-1, and DDLS8817 sarcoma cells, stable transduction of PIK3R3 shRNA did not alter proliferation in sarcoma cells grown as monolayers (Supplementary Fig. S1B) and had a small inhibitory effect in sarcoma cells grown as spheroids (Supplementary Fig. S1C). Here, PIK3R3 is linked to sarcoma.