Nanomaterials including metal or metal oxide nanoparticles, carbonous nanomaterial (e.g., carbon dots) or metal-organic framework nanoparticles provide porous, catalytically active surfaces and functional interfaces for binding of ions or molecular agents. By the conjugation of nucleic acids to the nanoparticles, hybrid nanostructures revealing emerging multimodal catalytic/photocatalytic activities, high loading capacities, and effective targeted cell permeation efficacies are formed. The review article exemplifies the application of nucleic acid-modified nanoparticles conjugates for therapeutic treatment of cancer cells. Stimuli-responsive reconfiguration of nucleic acid strands and the specific recognition and catalytic function of oligonucleotides associated with porous, catalytic, and photocatalytic nanoparticles yield hybrid composites demonstrating cooperative synergistic properties for medical applications. The targeted chemodynamic, photodynamic, photothermal and chemotherapeutic treatment of cancer cells by the oligonucleotide/nanoparticle conjugates is addressed. In addition, the application of oligonucleotide/nanoparticle conjugates for gene therapy treatment of cancer cells is discussed.