Fig 2: The expression levels of KCNQ1OT1 and PD-L1 were increased and the expression level of miR-506 was decreased in sorafenib-resistant HCC tissues. (A and B) The expression levels of KCNQ1OT1 and miR-506 in sorafenib-resistant HCC tissues and sorafenib-sensitive HCC tissues were measured by RT-qPCR. (C and D) RT-qPCR assay and immunohistochemistry were used to evaluate the level of PD-L1. Scale bar, 100 µm. (E-G) The correlations among KCNQ1OT1, miR-506 and PD-L1 were evaluated by Pearson's correlation analysis. *P<0.05. HCC, hepatocellular carcinoma; KCNQ1OT1, KCNQ1 overlapping transcript 1; PD-L1, programmed death-ligand-1; RT-qPCR, reverse transcription-quantitative PCR analysis.

Fig 3: KCNQ1OT1, miR-506 and PD-L1 were aberrantly expressed in sorafenib-resistant HCC cells. (A and B) SK-HEP-1, SK-HEP-1/sorafenib, Huh-7 and Huh-7/sorafenib cells were treated with different doses of sorafenib for 48 h and cell viability was evaluated by Cell Counting Kit-8 assay. (C-E) The expression levels of KCNQ1OT1, miR-506 and PD-L1 mRNA in SK-HEP-1 and SK-HEP-1/sorafenib cells were determined by RT-qPCR. (F) The protein level of PD-L1 in SK-HEP-1 and SK-HEP-1/sorafenib cells was examined by western blot assay. (G-I) The expression levels of KCNQ1OT1, miR-506 and PD-L1 mRNA in Huh-7 and Huh-7/sorafenib cells were determined by RT-qPCR. (J) The protein level of PD-L1 in Huh-7 and Huh-7/sorafenib cells was examined by western blot assay. *P<0.05. HCC, hepatocellular carcinoma; KCNQ1OT1, KCNQ1 overlapping transcript 1; PD-L1, programmed death-ligand-1; RT-qPCR, reverse transcription-quantitative PCR analysis.

Fig 4: Western blot analysis of EPO-related molecules in NSCLC cell lines. The expression of each protein was compared after 48 h intervention with rhEPO (0, 2, and 8 U/ml) under normoxic and hypoxic conditions. (A) The histogram showed the relative expression levels of VEGF, HIF-1a, and PD-L1 in A549 cells (*p < 0.05). (B) The histogram showed the relative expression levels of VEGF, HIF-1a, and PD-L1 in NCI-H838 cells (*p < 0.05). (C) Western blot bands. The immune response was developed by rabbit anti-VEGF antibody, rabbit anti-HIF-1a antibody, rabbit anti-PD-L1 antibody, and mouse anti-ß-actin monoclonal antibody. ß-actin was used as a loading control. The results represented the mean ± SD of three independent experiments. It showed a representative print. (N: Normoxia; H: Hypoxia). EPO, erythropoietin; HIF, hypoxia-inducible factor-1a; NSCLC, non-small-cell lung carcinoma; VEGF, vascular endothelial growth factor