荷兰奥德研究所Hans Clevers研究小组探讨了BAP1对CRISPR基因工程改造的人肝脏类器官的肿瘤抑制作用。 相关论文于2019年5月23日发表在《Cell Stem Cell》杂志上。

研究小组应用CRISPR/Cas9在正常人类胆管细胞类器官中使BAP1作用缺失。团队发现BAP1通过调控染色质的开放性来控制连接和细胞骨架组件的表达。研究人员观察到多种上皮特征的丧失，但运动性增强。重要的是，恢复细胞核中BAP1的催化活性可以挽救这些细胞和分子的变化。该课题组设计了人类肝脏的类器官来结合常见的胆管癌突变(TP53、PTEN、SMAD4和NF1)。在这种遗传背景下，BAP1缺失导致异种移植获得恶性特征。因此，通过调控染色质开放性来控制上皮细胞的特性似乎是BAP1抑癌功能的一个关键方面。有机体技术结合CRISPR/Cas9为人类癌症基因功能机制的研究提供了一个实验平台。

研究人员表示，去泛素酶BAP1是一种肿瘤抑制因子，与胆管癌有关。BAP1被提出有许多分子靶点，已知它的果蝇同源体可以使组蛋白H2AK119去泛素化。

附：英文原文

Title: Probing the Tumor Suppressor Function of BAP1 in CRISPR-Engineered Human Liver Organoids

Author: Benedetta Artegiani, Lisa van Voorthuijsen, Rik G.H. Lindeboom, Jacco van Rheenen, Michiel Vermeulen, Hans Clevers

Issue&Volume: Jun 06, 2019 Volume 24Issue 6

Abstract: The deubiquitinating enzyme BAP1 is a tumor suppressor, among others involved in cholangiocarcinoma. BAP1 has many proposed molecular targets, while its Drosophila homolog is known to deubiquitinate histone H2AK119. We introduce BAP1 loss-of-function by CRISPR/Cas9 in normal human cholangiocyte organoids. We find that BAP1 controls the expression of junctional and cytoskeleton components by regulating chromatin accessibility. Consequently, we observe loss of multiple epithelial characteristics while motility increases. Importantly, restoring the catalytic activity of BAP1 in the nucleus rescues these cellular and molecular changes. We engineer human liver organoids to combine four common cholangiocarcinoma mutations (TP53, PTEN, SMAD4, and NF1). In this genetic background, BAP1 loss results in acquisition of malignant features upon xenotransplantation. Thus, control of epithelial identity through the regulation of chromatin accessibility appears to be a key aspect of BAP1’s tumor suppressor function. Organoid technology combined with CRISPR/Cas9 provides an experimental platform for mechanistic studies of cancer gene function in a human context.

DOI: https://doi.org/10.1016/j.stem.2019.04.017

Source: https://www.cell.com/cell-stem-cell/fulltext/S1934-5909(19)30166-3