摘要
目的探究嗜黏蛋白阿克曼氏菌(A.muciniphila)代谢产物丙酸对结直肠癌放射敏感性的影响及机制。方法使用正常人结肠上皮细胞NCM460筛选合适丙酸浓度。使用A.muciniphila条件培养基或丙酸处理人结直肠癌细胞系HCT-8细胞并进行6 Gyγ射线照射,通过克隆形成实验和CCK-8实验检测细胞存活率和增殖能力。建立偶氮甲烷/葡聚糖硫酸钠(AOM/DSS)诱导的结直肠癌小鼠模型,将64只小鼠分为造模对照组、单纯照射组、照射+丙酸组,记录小鼠体重,评估结直肠长度、肿瘤数量和面积。通过HE染色、免疫组织化学染色、酶联免疫吸附实验评估丙酸的放射增敏效果,RT-PCR和流式细胞术探究具体机制。结果CCK-8实验显示,1 mmol/L丙酸对NCM460细胞增殖无明显影响(P>0.05),用于后续实验。克隆形成和CCK-8结果显示,A.muciniphila条件培养基或丙酸预处理后受照HCT-8细胞存活率和增殖能力显著下降(t=3.14~34.98,P<0.05)。结直肠癌模型小鼠中,照射+丙酸组小鼠较单纯照射组结直肠长度增加(t=3.50,P<0.05),肿瘤数量减少(t=3.48,P<0.05),两组较造模对照组肿瘤面积缩小(t=5.97、7.30,P<0.05)。HE染色和免疫组织化学染色显示丙酸使结直肠结构恢复,结直肠癌组织Ki67表达降低(t=14.50、3.40,P<0.05)。与单纯对照组相比,丙酸治疗可降低炎症因子白介素6(IL-6)[(28.04±10.44)pg/ml]和肿瘤坏死因子α(TNF-α)[(267.78±43.69)pg/ml]水平(t=4.86、5.06,P<0.05)。照射联合丙酸处理可进一步提高p53表达,加重G2/M期阻滞和细胞凋亡(t=20.35、13.05,P<0.05)。结论A.muciniphila代谢产物丙酸通过促进结直肠癌细胞发生G2/M期阻滞和细胞凋亡,发挥结直肠癌放射治疗增敏作用。
Objective To investigate the effects of propionic acid produced by Akkermansia muciniphila on the radiosensitivity of colorectal cancer and the underlying mechanism.Methods Normal human colon mucosal epithelial cells(NCM460)were used to determine the appropriate concentration of propionic acid.Human colorectal cancer cells(HCT-8)were treated with A.muciniphila-conditioned medium or propionic acid,followed by exposure to 6 Gyγ-ray irradiation,and cell survival and proliferation were measured by clone formation assay and Cell Counting Kit-8(CCK-8)assay,respectively.A mouse model of colorectal cancer was established using azoxymethane/dextran sodium sulfate.The mice were divided into control model group,irradiation group,and irradiation+propionic acid group.Their body weight,colorectal length,tumor count,and tumor area were recorded.The radiosensitizing effect of propionic acid was assessed with HE staining,immunohistochemical staining,and enzyme-linked immunosorbent assay.The mechanism was explored by using RT-PCR and flow cytometry.Results CCK-8 assay showed that 1-mmol/L propionic acid had no significant effect on the proliferation of NCM460 cells(P>0.05),which was used for subsequent experiments.Pretreated with A.muciniphila-conditioned medium or propionic acid,the survival and proliferation abilities of irradiated HCT cells were significantly decreased(t=3.14-34.98,P<0.05).Compared with the irradiation group,the colorectal cancer mice in the irradiation+propionic acid group showed a significantly longer colorectal length(t=3.50,P<0.05)and a significantly smaller number of tumors(t=3.48,P<0.05);the two groups had significantly smaller tumor areas than the control model group(t=5.97,7.30,P<0.05).HE staining and immunohistochemical staining showed that propionic acid restored colorectal structure,and decreased Ki67 expression in colorectal tissue(t=14.50,3.40,P<0.05).Propionic acid treatment significantly reduced the levels of the inflammatory factors interleukin-6 and tumor necrosis factor-α,as compared with the mice receiving irradiation alone(t=4.86,5.06,P<0.05).Irradiation plus propionic acid treatment significantly increased p53 expression and significantly aggravated G2/M phase block and cell apoptosis(t=20.35,13.05,P<0.05).Conclusions The A.muciniphila metabolite propionic acid plays a sensitizing role in radiation therapy for colorectal cancer by promoting G2/M phase block and apoptosis in colorectal cancer cells.
作者
肖雨浓
董佳丽
王齐
李源
董妍汐
邱吉巍
崔明
Xiao Yunong;Dong Jiali;Wang Qi;Li Yuan;Dong Yanxi;Qiu Jiwei;Cui Ming(State Key Laboratory of Advanced Medical Materials and Devices,Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Tianjin Institutes of Health Science,Institute of Radiation Medicine,Chinese Academy of Medical Sciences&Peking Union Medical College,Tianjin 300192,China)
出处
《中华放射医学与防护杂志》
北大核心
2025年第9期851-857,共7页
Chinese Journal of Radiological Medicine and Protection
基金
国家自然科学基金(82202944,82373524,32100087)
中央高校基本科研业务费专项资金(3332024214)。
关键词
结直肠癌
放射增敏
嗜黏蛋白阿克曼氏菌
丙酸
Colorectal cancer
Radiosensitivity
Akkermansia muciniphila
Propanoic acid
