Applications of nanozymes in the diagnosis and treatment of gastrointestinal malignancies

Table 1 Comparative analysis of natural enzymes and nanozymes

Feature	Natural enzymes	Nanozymes	GI oncology relevance	Ref.
Composition	Proteins or RNA	Metals, metal oxides, carbon, etc	Nanozymes possess a high density of active sites	[22]
Selectivity	High substrate specificity	Broad-spectrum/low specificity	Beneficial for multi-target TME modulation	[19]
Stability	Low (susceptible to protease, heat)	Extremely high (chemically robust)	Resists gastric acid and proteolytic enzymes in GI tract	[19]
Catalytic activity	High turnover rate (Kcat)	Tunable, pH/light/H2O2 responsive	Allows selective activation in acidic TME	[23]
Production cost	High (complex preparation/purification)	Low (facile chemical synthesis)	Enables large-scale clinical translate/screening	[24]
Multifunctionality	Single catalytic function	Integration with imaging/therapy	Facilitates theranostics (diagnosis + therapy)	[25]

TME: Tumor microenvironment; GI: Gastrointestinal.