Advances in anti-tumor research based on bionic micro-/nano technology

Abstract

<p indent="0mm">A malignant tumor is a serious disease that can cause great harm to human health. Currently, the clinical treatment of tumors primarily includes surgery, chemotherapy, and radiotherapy. However, these three methods can cause significant damage to patient health and are expensive, causing considerable financial duress to patients. Thus, there is a pressing need to determine safe, effective, and low-cost treatments for cancer. One of the primary reasons malignant tumors are difficult to treat is that tumor cells constantly adapt to their environment, thereby forming a suitable tumor microenvironment (TME) that supports their growth. The TME is composed of immune cells, inflammatory cells, cancer-associated fibroblasts, capillaries, and various cytokines and chemokines, thus forming a complex integrated system. As the living environment of tumor cells, it is closely related to tumor genesis, metastasis, and recurrence. It is believed that the TME is not a silent spectator but an active promoter of cancer progression. Compared with normal cells, tumor cells show a lack of oxygen, a weakly acidic environment, and physiological phenotypes that directly result in the lack of oxygen. Oxygen-dependent X-ray radiotherapy, chemical therapy, and photodynamic therapy; tumor cells also indirectly affect cell metabolism and largely reduce the toxicity of some drugs, thus greatly enhancing genetic instability. TME provides conditions for the rapid growth and evolution of tumor cells so that tumor cells develop strong drug resistance. Although physiological phenotypes, such as tumor hypoxia and weakly acidic microenvironment, affect the clinical efficacy of tumors to a certain extent, they also provide therapeutic targets and research entry points for new tumor diagnosis and treatment strategies. With the advances in bionics, molecular sciences, gene technology, and nanoscience, the bionic micro-nano fusion tumor therapy has become a research hotspot. Bionic treatment has opened new avenues for patients with malignant tumors owing to its good biocompatibility and is receiving increasing attention from researchers. This environmentally friendly, efficient, long-term, and low-cost treatment method has good clinical application prospects and is becoming an effective means of antitumor treatment. Researchers have drawn inspiration from nature to develop and design biomimetic antitumor materials with excellent biocompatibility compared with traditional medicine, stronger antitumor effect, and lower cost. From the perspective of improving the TME, this paper describes the advantages of four types of tumor biomimetic treatment materials, analyzes the therapeutic effects of each material, summarizes the problems faced in their commercial use, and prospects the future applications of these materials.