Figure 4. siORC1 enhances HU sensitivity of additional tumour-derived cell lines (HeLa and MDA-MB-231) but does not affect non-tumour cells (BJhTERT, 48BR, and MRC5).

(A-G) BJhTERT and were transfected with 5nM, 48BR, MRC-5, and MDA-MB-231 with 1 nM, and HeLa with 0.6 nM siRNA oligonucleotides. (A) ORC1 protein was assessed by immunoblotting 48 hours later. (B) Viability was assessed 7 days later. Analyses using different siORC1 oligonucleotide concentrations are shown in Supplementary Fig. S4. (C-G) Viability was assessed as in Fig. 1D-E using indicated HU treatment times to achieve complete HU-induced S phase arrest (Supplementary Fig. S5A-E).