IGF1R and neoplasm: Consistent with the observations in cell culture under hypoxia, immunoblotting analysis of tumor tissues indicated expression of both rPYCR1 Y135F and rPYCR1 T238A notably increased the protein level of ELK4-target genes like KLK10 and CNN1 (Fig. 6b and Supplementary Fig. 6d), in which the elevated IGF1R phosphorylation was associated with the induction of PYCR1-Y135 phosphorylation in groups of WT rPYCR1 and rPYCR1 T238A.