Fig. 5From: Targeting IGF1R signaling enhances the sensitivity of cisplatin by inhibiting proline and arginine metabolism in oesophageal squamous cell carcinoma under hypoxiaIGF1R regulates the expression of ASS1 and PYCR1 through its signaling pathway–c-MYC axis under hypoxia. A Correlation between IGF1R expression and PYCR1 or ASS1 expression in OSCC tissues obtained from TMA analysis. B Protein levels of ASS1 and PYCR1 in OSCC cells transfected with siRNA-control/IGF1R cultured under limited-oxygen conditions. C Protein levels of RAS/MAPK and JAK/STAT in OSCC cells transfected with shRNA-control/IGF1R. D Protein levels of ASS1 and PYCR1 in OSCC cells transfected with siRNA-control/JAK (left) or siRNA-control/ERK (right). E Protein levels of ASS1 and PYCR1 in OSCC cells transfected with siRNA-control/c-MYC. F Protein levels of c-MYCT58 in OSCC cells transfected with siRNA-control/JAK (Top) or siRNA-control/ERK (Bottom). G, H, I Predicted sequences of c-MYC motifs (G) at the ASS1 (H) and PYCR1 (I) promoters determined using JASPAR. J, K ChIP-PCR analysis of c-MYC enrichment at the ASS1 (J) and PYCR1 (K) promoters. L, M Schematic diagram of luciferase reporter plasmids, which were constructed containing the wild ASS1(L)/PYCR1(M) promoters or mutant c-MYC motif. N, O Transactivation activity of indicated ASS1 (N) and PYCR1 (O) promoters in KYSE150 cells from luciferase reporter gene assays. P Protein levels of cMYC, c-MYC.T58, ASS1 and PYCR1 in OSCC cells transfected with siRNA-control/IGF1R cultured in limited oxygen. Student’s t test. *p < 0.05, **p < 0.01, ***p < 0.001Back to article page