The efficiency and specificity of IP3R1, IP3R2 and IP3R3 gene silencing following the transfection by specific siRNAs were confirmed by quantitative real-time PCR (Supplementary Figure 2 and Table 4A) and Western-blot (Supplementary Figure 3 and Table 4B) on the three breast cancer cell lines. This evidence concerns the gene ITPR1 and breast carcinoma.