消除 K458 乙酰化增强了肝细胞核因子 4α（HNF4α）诱导的肝细胞癌分化治疗。

Abrogating K458 acetylation enhances hepatocyte nuclear factor 4α (HNF4α)-induced differentiation therapy for hepatocellular carcinoma.

机构信息

Department of Gastroenterology, Changzheng Hospital, Naval Medical University, Shanghai, China.

Department of Gastroenterology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.

出版信息

J Dig Dis. 2024 Apr;25(4):255-265. doi: 10.1111/1751-2980.13272.

DOI:10.1111/1751-2980.13272

PMID:38837552

Abstract

OBJECTIVES

In this study we aimed to assess the impact of acetylation of hepatocyte nuclear factor 4α (HNF4α) on lysine 458 on the differentiation therapy of hepatocellular carcinoma (HCC).

METHODS

Periodic acid-Schiff (PAS) staining, Dil-acetylated low-density lipoprotein (Dil-Ac-LDL) uptake, and senescence-associated β-galactosidase (SA-β-gal) activity analysis were performed to assess the differentiation of HCC cells. HNF4α protein was detected by western blot and immunohistochemistry (IHC). The effects of HNF4α-K458 acetylation on HCC malignancy were evaluated in HCC cell lines, a Huh-7 xenograft mouse model, and an orthotopic model. The differential expression genes in Huh-7 xenograft tumors were screened by RNA-sequencing analysis.

RESULTS

K458R significantly enhanced the inhibitory effect of HNF4α on the malignancy of HCC cells, whereas K458Q reduced the inhibitory effects of HNF4α. Moreover, K458R promoted, while K458Q decreased, HNF4α-induced HCC cell differentiation. K458R stabilized HNF4α, while K458Q accelerated the degradation of HNF4α via the ubiquitin proteasome system. K458R also enhanced the ability of HNF4α to inhibit cell growth of HCC in the Huh-7 xenograft mouse model and the orthotopic model. RNA-sequencing analysis revealed that inhibiting K458 acetylation enhanced the transcriptional activity of HNF4α without altering the transcriptome induced by HNF4α in HCC.

CONCLUSION

Our data revealed that inhibiting K458 acetylation of HNF4α might provide a more promising candidate for differential therapy of HCC.

摘要

目的

本研究旨在评估组蛋白 4α（HNF4α）赖氨酸 458 乙酰化对肝细胞癌（HCC）分化治疗的影响。

方法

通过过碘酸希夫（PAS）染色、二乙酸低密度脂蛋白（Dil-Ac-LDL）摄取和衰老相关β-半乳糖苷酶（SA-β-gal）活性分析来评估 HCC 细胞的分化。通过 Western blot 和免疫组织化学（IHC）检测 HNF4α 蛋白。在 HCC 细胞系、Huh-7 异种移植小鼠模型和原位模型中评估 HNF4α-K458 乙酰化对 HCC 恶性程度的影响。通过 RNA 测序分析筛选 Huh-7 异种移植瘤中的差异表达基因。

结果

K458R 显著增强了 HNF4α对 HCC 细胞恶性程度的抑制作用，而 K458Q 则降低了 HNF4α 的抑制作用。此外，K458R 促进了 HNF4α诱导的 HCC 细胞分化，而 K458Q 则降低了 HNF4α 的诱导作用。K458R 稳定了 HNF4α，而 K458Q 通过泛素蛋白酶体系统加速了 HNF4α 的降解。K458R 还增强了 HNF4α 在 Huh-7 异种移植小鼠模型和原位模型中抑制 HCC 细胞生长的能力。RNA 测序分析表明，抑制 HNF4α-K458 乙酰化增强了 HNF4α 的转录活性，而不改变 HNF4α 在 HCC 中诱导的转录组。