Tumor-suppressing proteins in Lrp5 CM. CN = control, CM = osteoblast-derived conditioned medium, siLrp5 = Lrp5 siRNA, Lrp5 = Lrp5 overexpression, OPN = osteopontin overexpression, Hsp = Hsp90ab1, MSN = moesin, and Ob = osteoblasts. The single and double asterisks indicate p < 0.05 and 0.01, respectively. (A) Elevation of Hsp90ab1 and MSN in Lrp5 CM and OPN CM, and the reduction in Lrp5-silenced CM. (B) Levels of Hsp90ab1 and moesin in Ob CM and Lrp5 CM. (C-D) Reduction in the EdU-based proliferation and transwell invasion of EO771 mammary tumor cells by the application of 5 µg/mL Hsp90ab1 and MSN. (E-F) Tumor selectivity of Lrp5 Ob CM, Hsp90ab1, and MSN. Using MTT-based viability, tumor selectivity was defined as the reduction for tumor cells (EO771, MDA-MB-231, and TRAMP cells) to the reduction for non-tumor cells (MSCs, MC3T3, adipose-MSCs, and KTB6-hTERT control epithelial cells). Of note, N.D. (not defined) was used when the metabolic activities of non-tumor cells were stimulated.