Background: The utility of frequently used serum tumor markers in breast cancer remains controversial. The study aimed to investigate the role of preoperative carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), cancer antigen 153 (CA153), cancer antigen 724 (CA724), and ferritin (FER) in the management of breast cancer and their relationships with pathological features.Methods: A total of 804 patients with breast mass who underwent breast surgery and 305 healthy volunteers were enrolled. Preoperative serum levels of CEA, CA125, CA153, CA724, and FER were measured. And the pathological features of all the patients were recorded. The association of preoperative serum tumor markers and pathological features was analyzed.Results: Among the 804 patients, 355 were identified as malignant cases and 449 as benign cases. CEA, CA153, and FER of patients with breast cancer were higher than those of healthy volunteer group and patients with benign breast diseases. The area under curve (AUC) of CEA, CA153, and FER for distinguishing patients with breast cancer and subjects with non‐breast cancer was 0.688 (95% CI: 0.656‐0.721), 0.609 (95% CI: 0.574‐0.645), and 0.623 (95% CI: 0.586‐0.660), respectively. CA153 correlated with tumor size, node status, and TNM stage, whereas CA125 with node status. No statistic differences of the five markers were observed among the four molecular subtypes.Conclusion: Preoperative levels of CEA, CA153, and FER exhibit low diagnostic accuracy for breast cancer (stage I‐III). CA153 correlates with tumor burden, suggesting its prognostic value. The five serum markers do not correlate with molecular subtypes.

Platinum nanozymes exhibiting highly efficient and robust oxidase-like activity are successfully synthesized and modified using sodium alginate (SA-PtNPs). According to a steady-state dynamic assay, Michaelis-Menton constant (K_m) is calculated as 11.6 μM, indicating that the affinity of SA-PtNPs toward the substrate, 3, 3′, 5, 5′-tetramethylbenzidine (TMB), is high. It shows in the paper that SA-PtNPs exhibit a significant oxidant effect on substrate-O₂ to produce ${\text{O}}_2^{•-}$ as an oxidase mimic. Moreover, the oxidase-like activity fluctuated slightly under changes in environmental pH and incubation time, implying that SA can increase the dispersibility and stability of PtNPs. A colorimetric assay for oligomeric proanthocyanidins (OPC) was realized given how few explorations of the former there are. We found that the significant inhibitory effect of OPC on the oxidase-like activity is due to the competitive effect between OPC and TMB for binding to the active site of SA-PtNPs, resulting in a color change. Under optimal conditions, the logarithmic value of the chromogenic difference (ΔA_450nm) to OPC concentration was linear (4–32.5 μM, r = 0.999) with a limit of detection (LOD) of 2.0 μM. The antioxidant capacity of OPC obtained by the Soxhlet extraction method from grape seeds was 2.85 U/mg. The recovery from the experiment in which OPC was added to grape seeds ranged from 97.0 to 98.6% (RSDs of 0.5–3.4%), suggesting a high accuracy in OPC detection. These findings are important because OPC is an internationally recognized antioxidant that eliminates free radicals in the human body and, therefore, may prevent a variety of diseases. Thus, we envisage that this Pt nanozyme-based assay may be prevalent for antioxidant capacity evaluation and analytical applications.

We herein report the intrinsic alkaline peroxidase-like activity exhibited by CuO nanoparticles when 3-(4-hydroxyphenyl)propionic acid was employed as a substrate. Based on this observation, a fluorometric assay method with a low detection limit of 0.81 μM was established for H₂O₂ determination under alkaline conditions. Notably, ammonia was found to inhibit the alkaline peroxidase-like activity of the CuO nanoparticles. Thus, a sensing platform for the determination of urea and urease was successfully constructed, with the limits of detection for urea and urease being 27 μM and 2.6 U L⁻¹, respectively. This platform was then applied for the detection of urea in human urine and urease in soil, which yielded satisfactory results. These results suggest that it is possible to extend the catalytic potential of peroxidase and its mimetics from acidic and neutral conditions to include activity in alkaline media as well. Furthermore, this strategy is a novel method for the analysis of urea and urease. The assay developed in this work is facile, inexpensive, convenient, and highly selective and sensitive. Therefore, it is expected that this system can serve as a template for the development of similar enzyme nano-mimics.