The systematic analysis performed using spectroscopic techniques to compare the ability of AgTMPyP, ZnTMPyP, and the free base H2TMPyP to stabilize biologically relevant G4 DNA structures—particularly those associated with cancer-related sequences such as G4 Tel, MYC, and KRAS, revealed that AgTMPyP is a promising new ligand for stabilizing G4 structures, especially oncogenic sequences, followed by ZnTMPyP. This evidence concerns the gene MYC and cancer.