The levels of ROR, miR-153-3p, and ABCB1 in cisplatin-resistant OS tissues and cells were detected by qRT-PCR and/or Western blot assay. 
qRT-PCR
The levels of ROR, miR-153-3p, and ABCB1 in cisplatin-resistant OS tissues and cells were detected by qRT-PCR and/or Western blot assay. 
Western blot assay
The interactions of miR-153-3p, ROR, and ABCB1 were predicted by miRcode Tools and StarBase v2.0 online database, respectively, and validated by Dual-Luciferase reporter assay.  MiRcode Tools and StarBase v2.0 predicted that miR-153-3p had complementary sequences with ROR and ABCB1 3'UTR, and following Dual-Luciferase reporter assay validated that miR-153-3p was a direct target of ROR and ABCB1. 
miRcode Tools
The interactions of miR-153-3p, ROR, and ABCB1 were predicted by miRcode Tools and StarBase v2.0 online database, respectively, and validated by Dual-Luciferase reporter assay. 
StarBase v2.0 online database
The interactions of miR-153-3p, ROR, and ABCB1 were predicted by miRcode Tools and StarBase v2.0 online database, respectively, and validated by Dual-Luciferase reporter assay.  MiRcode Tools and StarBase v2.0 predicted that miR-153-3p had complementary sequences with ROR and ABCB1 3'UTR, and following Dual-Luciferase reporter assay validated that miR-153-3p was a direct target of ROR and ABCB1. 
Dual-Luciferase reporter assay
The cell viability in different concentrations of DDP, cell proliferative capacity, migrated cells, and invaded cells were detected by MTT assay and transwell assay, respectively.



MTT assay
The cell viability in different concentrations of DDP, cell proliferative capacity, migrated cells, and invaded cells were detected by MTT assay and transwell assay, respectively.



transwell assay