Nanobubbles: An emerging therapeutic paradigm for targeted cancer therapy

Recently, nanobubbles (NBs) have emerged as a groundbreaking platform for drug and gene delivery in the targeted treatment of cancer because of their unique advantages. The nanoscale dimensions, stability, and responsiveness to external triggers-for example, ultrasound-allow for highly selective localization and controlled release of therapeutic agents in tumor tissues. This review highlights the capability of NBs, when combined with ultrasound activation, to significantly improve the intracellular uptake, penetration, and therapeutic efficacy of chemotherapeutic agents, thus diminishing their off-target toxicity. In addition, NB-based strategies have also been extended to innovative applications, including their application utilizing gold nanoclusters to detect and eradicate residual cancer cells after surgery. Reduced surface tension due to the NB shell architecture is a critical element in ensuring stability, sustaining circulation, and targeted delivery of NBs. In addition, NBs also have great potential to reverse tumor hypoxia, sensitizing drug-resistant cancer cells, and provide gene editing therapy. This novel method represents a significant step forward in the development of site-specific, minimally invasive, and highly effective cancer treatments. In this review, the design, mechanisms, therapeutic applications, recent advances, and future prospects of NB-based strategies for the eradication of cancer are comprehensively discussed.