HOXC8在Cr（VI）暴露的BEAS-2B细胞中调控EZH2帽依赖性蛋白翻译研究

刘梦丹; 陈嘉弘; 孙若晗; 朱勇飞; 张玉静

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湖南师范大学学报医学版 ›› 2025, Vol. 22 ›› Issue (1) : 31-38.

基础医学

HOXC8在Cr（VI）暴露的BEAS-2B细胞中调控EZH2帽依赖性蛋白翻译研究

刘梦丹¹, 陈嘉弘¹, 孙若晗¹, 朱勇飞¹, 张玉静^1,2

作者信息 +

Study on the regulation of cap-dependent protein translation of EZH2 by HOXC8 in Cr(VI)-exposed BEAS-2B Cells

LIU Mengdan¹, CHEN Jiahong¹, SUN Ruohan¹, ZHU Yongfei¹, ZHANG Yujing^1,2

Author information +

文章历史 +

摘要

目的：探讨同源盒基因C8（homeobox gene C8,HOXC8）在长期六价铬[hexavalent chromium,Cr（Ⅵ）]暴露诱导BEAS-2B细胞恶性转化过程中对zeste增强子同源物2（enhancer of zeste homolog 2,EZH2）的调控作用,为进一步探讨Cr（VI）可能致肺癌的分子机制提供线索。方法：采用细胞计数、克隆形成实验、软琼脂实验及细胞球体形成实验等检测细胞增殖和非锚定依赖性生长能力的改变;采用TIMER2.0、HPA、Kaplan-Meier数据库分析HOXC8在肺癌中的表达情况及其对肺癌患者生存率的影响;采用慢病毒技术构建HOXC8沉默表达的BEAS-2B和A549细胞株;实时荧光定量PCR检测HOXC8的mRNA表达水平;Western Blot分析HOXC8、EZH2及哺乳动物雷帕霉素靶蛋白（mammalian target of rapamycin,mTOR）信号通路相关蛋白的表达改变;双荧光素酶报告基因实验检测HOXC8高表达的A549细胞和Cr（VI）暴露的BEAS-2B细胞中EZH2帽依赖性蛋白翻译的改变。结果：与对照组相比,长期暴露于Cr（VI）的BEAS-2B细胞增殖能力显著增强,并且表现出较强的非锚定依赖性生长能力;生物信息学分析结果显示HOXC8在肺癌中的表达显著增高,免疫组化结果表明HOXC8在肺癌组织中表达显著增高,且HOXC8与肺癌患者无复发生存率密切相关;HOXC8、EZH2及蛋白翻译相关mTOR信号通路蛋白mTOR、4EBP1在Cr（VI）暴露细胞中表达增高;抑制HOXC8表达可降低Cr（VI）暴露引起的细胞异常增殖及EZH2、mTOR和4EBP1的表达,还可抑制EZH2的帽依赖性蛋白翻译过程;此外,抑制A549细胞中HOXC8表达也可降低EZH2的帽依赖性蛋白翻译。结论：HOXC8在Cr（VI）诱导的恶性转化的BEAS-2B细胞中通过mTOR信号通路调控EZH2帽依赖性蛋白翻译。

Abstract

Objective To investigate the regulatory effect of homeobox gene C8 (HOXC8) on zeste enhancer homologue 2(EZH2) during the malignant transformation of BEAS-2B cells induced by long-term hexavalent chromium [Cr(VI)] exposure, this study may provide a clue to the molecular mechanism of Cr(VI)-induced chronic lung injury. Methods Cell counting, clone formation experiment, soft agar experiment and cell sphere formation experiment were used to detect the changes of cell proliferation and anchorage-independent growth ability. TIMER2.0, HPA and Kaplan-Meier databases were used to analyze the expression of HOXC8 in lung cancer and its influence on the survival rate of patients with lung cancer. BEAS-2B and A549 cell lines were constructed by lentivirus technology. The real-time quantitative PCR was used to detect the mRNA expression of HOXC8. The expression of HOXC8, EZH2 and related proteins of mammalian Sirolimus target proteins(mTOR) were analyzed by Western Blot. Dual-luciferase reporter assay detected altered EZH2 cap-dependent protein translation in HOXC8-overexpressed A549 cells and Cr(VI)-exposed BEAS-2B cells. Results Compared with the control group, the proliferative capacity of BEAS-2B cells exposed to Cr(VI) for a long time is significantly enhanced, and they show a relatively strong anchorage-independent growth ability. The results of bioinformatics analysis show that the expression of HOXC8 in lung cancer is significantly increased. Immunohistochemical results indicate that the expression of HOXC8 in lung cancer tissues is significantly increased, and HOXC8 is closely related to the recurrence-free survival rate of lung cancer patients. The expressions of HOXC8, EZH2 and protein translation-related mTOR signaling pathway proteins mTOR and 4EBP-1 are increased in Cr(VI)-exposed cells. Inhibiting the expression of HOXC8 can reduce the abnormal cell proliferation caused by Cr(VI) exposure and the expressions of EZH2, mTOR and 4EBP1, and can also inhibit the cap-dependent protein translation process of EZH2. In addition, inhibiting the expression of HOXC8 in A549 cells can also reduce the cap-dependent protein translation of EZH2. Conclusion HOXC8 regulates EZH2 cap - dependent protein translation via the mTOR signaling pathway in Cr(VI)-induced malignantly transformed BEAS - 2B cells.

导出引用

刘梦丹, 陈嘉弘, 孙若晗, 朱勇飞, 张玉静. HOXC8在Cr（VI）暴露的BEAS-2B细胞中调控EZH2帽依赖性蛋白翻译研究[J]. 湖南师范大学学报医学版. 2025, 22(1): 31-38

LIU Mengdan, CHEN Jiahong, SUN Ruohan, ZHU Yongfei, ZHANG Yujing. Study on the regulation of cap-dependent protein translation of EZH2 by HOXC8 in Cr(VI)-exposed BEAS-2B Cells[J]. Journal of Hunan Normal University(Medical Science). 2025, 22(1): 31-38

中图分类号： R114

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