Nanotechnology for Multimodal Synergistic Cancer Therapy.

The complexity, diversity, and heterogeneity of tumors seriously undermine the therapeutic potential of treatment. Therefore, the current trend in clinical research has gradually shifted from a focus on monotherapy to combination therapy for enhanced treatment efficacy. More importantly, the cooperative enhancement interactions between several types of monotherapy contribute to the naissance of multimodal synergistic therapy, which results in remarkable superadditive (namely "1 + 1 > 2") effects, stronger than any single therapy or their theoretical combination. In this review, state-of-the-art studies concerning recent advances in nanotechnology-mediated multimodal synergistic therapy will be systematically discussed, with an emphasis on the construction of multifunctional nanomaterials for realizing bimodal and trimodal synergistic therapy as well as the intensive exploration of the underlying synergistic mechanisms for explaining the significant improvements in synergistic therapeutic outcome. Furthermore, the featured applications of multimodal synergistic therapy in overcoming tumor multidrug resistance, hypoxia, and metastasis will also be discussed in detail, which may provide new ways for the efficient regression and even elimination of drug resistant, hypoxic solid, or distant metastatic tumors. Finally, some design tips for multifunctional nanomaterials and an outlook on the future development of multimodal synergistic therapy will be provided, highlighting key scientific issues and technical challenges and requiring remediation to accelerate clinical translation.