Cancer cells predominantly utilize aerobic glycolysis for energy production, preferentially converting glucose (Glu) to pyruvate (PA) and subsequently to lactate (LA). This metabolic reprogramming results in extracellular LA accumulation, acidifying the tumor microenvironment (TME) and facilitating tumor invasion and metastasis. The dynamics of Glu, PA, and LA are pivotal to tumor initiation and progression. This review comprehensively discussed therapeutic strategies targeting these key metabolites and systematically evaluates electrochemical and fluorescence-based techniques for their dynamic monitoring. We highlight the critical role of these monitoring approaches in advancing early cancer diagnosis, enabling personalized treatment, and accelerating anticancer drug development.

Confined catalysis enhances enzyme activity, stability, and selectivity by encapsulating enzymes in well-defined micro- or nanoscale environments. Unlike conventional immobilization strategies, which primarily stabilize enzymes, this approach actively regulates enzyme behavior, substrate transport, and product removal, addressing challenges in real-world biosensing. In this work, we connect confined catalysis principles with biosensor design requirements, emphasizing tailored microenvironments, hierarchical pore architectures, and cascade reaction optimization to improve sensitivity, selectivity, and operational stability. The review also highlights advanced strategies such as molecular imprinting, aptamer recognition, and DNA scaffold-guided co-localization, which enable precise substrate discrimination and efficient signal amplification. By integrating these confinement strategies with emerging materials, including biological macromolecular materials, amorphous porous materials, and crystalline framework materials, this work outlines pathways to next-generation biosensors with enhanced performance and practical applicability, addressing limitations overlooked in previous studies.