Figure 5.

Iron-(Fe³⁺) regulates colorectal cancer development via hTERT activation. A, Table showing the distribution of CMS among the patient cohort segregated by iron-(Fe³⁺) and Pirin levels in their tumor and normal sections. B, Graph showing the percentage distribution of CMS types among the patient cohort with positive and negative staining for iron and Pirin. C, List of primary patient-derived cell lines indicating the patient ID, tumor site, genomic alterations (microsatellite stable: MSS/microsatellite instable: MSI), and CMS status. D, qPCR-based expression quantification of hTERT gene in various patient-derived (primary) cell lines. Expression was normalized to β-actin levels. E, qPCR-based mRNA quantification of hTERT in PDCs treated with SP2509 (3 µmol/L) or DMSO for 48 hours. F and G, Telomerase activity (F) measured by TRAP and qPCR-based mRNA quantification of hTERT (G) in PDO representing different CMS types. PDOs were treated with SP2509 or DMSO for 48 hours. Each organoid represents a different CMS. Error bars indicate the standard deviation of three biological replicates. *, P < 0.05; **, P < 0.005; ***, P < 0.0001. H, Image of PDX tumors after termination of treatment in NSG mouse groups injected with SP2509 or DMSO. I, Graph showing tumor volume over a 2-week study period in NSG mice groups injected with SP2509 (30 mg/kg) or DMSO (twice weekly). *, P < 0.05; **, P < 0.005; ***, P < 0.0001.