Fig. 1

Sorafenib induces nuclear accumulation of miR-21 and SNHG1 that are overexpressed in sorafenib-resistant HCC cells. a-c Huh7 cells were incubated with sorafenib (2.5 μM) for 48 h. Total RNA was extracted from nuclear (NU) and cytoplasmic (CY) fractions, and the expression of SNHG1 (a) and miR-21 (b) was measured by qRT-PCR and normalized. U1 and U6 were used as internal nuclear controls for SNHG1 and miR-21, respectively. GAPDH was used as a cytoplasmic control. The results were expressed as means ± SD (n = 3). c The above cells were subjected to in situ hybridizations of miR-21 (5′-DIG tagged probe, identified with Cy3-conjugated Ab in red) and SNHG1 (5′-DIG tagged probe, identified with FITC-conjugated Ab in green), and stained with DAPI (blue). Three images from the same cell were merged. d Huh7 and Huh7-SR cells were untreated (mock) or transfected with negative control (NC), siRNA targeting SNHG1 (SNHG1-si) and SNHG1-smart Silencer for 24 h. The expression of SNHG1 was detected in nuclear and cytoplasmic fractions as above. “*” (P < 0.05) and “**” (P < 0.001) indicate a significant difference