Fig. 1From: The DNA secondary structures at telomeres and genome instabilityTargeting G-quadruplex structures in telomerase positive or ALT cancer cells. Left: unresolved G4s block the function of telomerase for telomere elongation in telomerase positive cells; Middle: stabilized G4s at some oncogene promoters lead to the repression of those oncogenes; Right: Targeting G-loop with G4s ligands or R-loop inhibitors may be a potential therapeutics for ALT cancersBack to article page