ESR Data for

Traditionally, the yeast cell wall (YCW) has limited applications because of its low solubility. To overcome this, a novel method was developed using a hydrothermal reaction to enhance its solubility and decrease its viscosity; this resulted in the production of a soluble form of YCW, known as the YCW treated with hydrothermal reaction (YCW-H), with broader chemical composition. However, the biological impact of YCW-H is unclear, excluding its reported plant growth-promotion by effectively regulating soil microspheres. This study investigated the potential of YCW-H to inhibit MCF-7 breast cancer cell proliferation. YCW-H demonstrated significant anti-proliferative effects on MCF7 cells, reducing cell growth by 58.7% ± 6.9 even when physically separated from the cells by a plastic wall. The observation suggests the presence of a diffusible factor against cell proliferation in YCW-H, a phenomenon not observed in the presence of untreated YCW. Reactive carbon species (RCS) generated during the hydrothermal treatment of YCW could be responsible for the effect. The addition of Fe(III) ions into YCW-H further amplified RCS production and elevated its inhibitory activity by about 10% across the plastic barrier. Radical adduct concentration of H2O in a tube which was incubated in YCW-H was 0.47 μmol/L, indicating that radicals migrated into the water through the plastic wall. The concentration of radical adducts in H2O in a tube exposed to YCW-H with Fe(III) ions further increased to 0.51 μmol/L, indicating that the growth inhibition was correlated with the increased RCS levels. Furthermore, flow cytometry analysis revealed the cytotoxic effects of YCW-H, indicating YCW-H is applicable to cancer therapy. Therefore, the findings highlight the pivotal role of RCS in the YCW-H anti-cancer activity, suggesting its potential as a promising candidate for the development of novel medical devices for cancer treatment.

传统上，酵母细胞壁（yeast cell wall, YCW）因溶解性较差，应用场景受限。为解决这一局限，本研究开发了一种基于水热反应（hydrothermal reaction）的新型处理方法，以提升其溶解性并降低黏度，最终获得可溶形式的YCW，命名为水热反应处理酵母细胞壁（YCW treated with hydrothermal reaction, YCW-H），其化学组成更为丰富。不过目前针对YCW-H的生物学效应仍不明确，除了已报道的其可通过有效调控土壤微球促进植物生长之外，其他相关信息均未明确。本研究探讨了YCW-H抑制MCF-7乳腺癌细胞增殖的潜力。实验结果显示，YCW-H对MCF-7细胞具有显著的抗增殖作用：即使通过塑料壁与细胞实现物理分隔，仍可使细胞生长降低58.7%±6.9%。该现象表明YCW-H中存在可扩散的抗细胞增殖因子，而未经处理的YCW未表现出该效应。在YCW的水热处理过程中产生的活性碳物种（reactive carbon species, RCS）可能是该效应的诱因。向YCW-H中添加三价铁（Fe(III)）离子，可进一步提升RCS的生成量，并使跨塑料屏障的细胞抑制活性提升约10%。置于YCW-H体系中孵育的试管内，水中的自由基加合物浓度为0.47 μmol/L，表明自由基可通过塑料壁迁移至水中；而添加Fe(III)离子的YCW-H体系对应的水中自由基加合物浓度进一步升高至0.51 μmol/L，说明细胞生长抑制效应与RCS水平升高呈显著正相关。此外，流式细胞术（flow cytometry）分析结果证实了YCW-H的细胞毒性作用，表明其可应用于癌症治疗。综上，本研究结果凸显了RCS在YCW-H抗癌活性中的关键作用，提示YCW-H有望成为开发新型癌症治疗医疗器械的潜在候选材料。