SRSF3 耗竭导致 SNU-368 HCC 细胞中 SF3B4 表达增加。

SRSF3 Depletion Leads to an Increase in SF3B4 Expression in SNU-368 HCC Cells.

机构信息

Department of Biochemistry, The Catholic University of Korea, Seoul, Republic of Korea.

The Institute of Aging and Metabolic Diseases, The Catholic University of Korea, Seoul, Republic of Korea.

出版信息

Anticancer Res. 2020 Apr;40(4):2033-2042. doi: 10.21873/anticanres.14160.

DOI:10.21873/anticanres.14160

PMID:32234894

Abstract

BACKGROUND

SF3B4, a critical component of U2 pre-mRNA spliceosomal complex, has been recently indicated as a potential oncogene in hepatocellular carcinoma (HCC). However, limited information exists on how SF3B4 expression is regulated in HCC.

MATERIALS AND METHODS

To determine the regulatory factor for SF3B4 expression, small interfering RNA (siRNA), real-time polymerase chain reaction (qRT-PCR) and western blotting assay were performed. The in vivo expression profiles of SRSF3 and SF3B4 were analyzed using public datasets and clinical samples.

RESULTS

Among 10 liver-specific splicing factors, only SRSF3 knockdown resulted in a significant increase in SF3B4 mRNA and consequently protein levels in SNU-368 HCC cells, probably via the retardation of SF3B4 mRNA decay rates. Using green fluorescent protein-SF3B4 fusion construct, the coding region of SF3B4 was found to be involved in SRSF3-mediated regulation of SF3B4 expression. Publicly available data from paired normal and tumor tissues in HCC and results from patients with HCC suggest that SRSF3 and SF3B4 possess an inverse relationship.

CONCLUSION

SRSF3 is a key molecule for determining SF3B4 levels in HCC cells.

摘要

背景

SF3B4 是 U2 前体 mRNA 剪接体复合物的关键组成部分，最近被认为是肝细胞癌（HCC）中的潜在癌基因。然而，SF3B4 表达如何受到调控的信息有限。

材料与方法

为了确定 SF3B4 表达的调节因子，采用小干扰 RNA（siRNA）、实时聚合酶链反应（qRT-PCR）和 Western blot 分析进行检测。利用公共数据集和临床样本分析 SRSF3 和 SF3B4 的体内表达谱。

结果

在 10 种肝特异性剪接因子中，只有 SRSF3 敲低导致 SNU-368 HCC 细胞中 SF3B4 mRNA 及其蛋白水平显著增加，可能是通过减缓 SF3B4 mRNA 降解速率实现的。使用绿色荧光蛋白-SF3B4 融合构建体，发现 SF3B4 的编码区参与了 SRSF3 对 SF3B4 表达的调节。来自 HCC 中配对的正常和肿瘤组织的公共数据以及 HCC 患者的结果表明，SRSF3 和 SF3B4 呈负相关。