SETD2基因调控DVL3对MDS患者骨髓细胞生物学功能的影响

The histone H3K36 methyltransferase SETD2 contributes to the regulation of hematological tumorigenesis and progression. Emerging evidence indicates that SETD2 deficiency impairs hematopoietic stem cells and causes malignant transformation to MDS in mice. However, its mechanism in MDS patients remains unclear. The applicant’s study revealed that SETD2 gene was closely associated with progression-free survival time in MDS patients, and the increased expression level of DVL3 mRNA and β-catenin of bone marrow cells was observed in patients with SETD2 gene aberration. Based on these findings, the applicant hypothesizes that SETD2 gene regulated β-catenin through DVL3 to promote the progression of MDS disease. In this study, the applicant will use the patient samples, SKM-1 cell lines and SETD2 knockout mice to confirm SETD2 gene regulating the expression of β-catenin mediated by DVL3, and test the effect of SETD2 on cell proliferation, differentiation and apoptosis in the transplanted mice. This study will illustrate that SETD2 gene affects the activity of Wnt/β-catenin signaling pathway by regulating the expression of DVL3, which may provide novel experimental evidence for finding prognostic markers and therapeutic targets for MDS.

组蛋白H3K36甲基转移酶SETD2参与并调控恶性血液肿瘤的发生发展。新的证据表明SETD2基因缺失可引起小鼠造血干细胞发生MDS恶性转化，然而，在MDS患者中SETD2基因的作用机制尚不清楚。申请者的前期研究发现，SETD2基因与MDS患者无进展生存时间密切相关，并且伴有SETD2基因异常的患者骨髓细胞DVL3-mRNA及核内β-catenin蛋白表达显著增高。因此，申请者假设SETD2基因经DVL3调控β-catenin进而促进MDS疾病进展。本课题利用MDS患者骨髓细胞、SKM-1细胞系及SETD2敲除小鼠证实SETD2基因通过调控DVL3介导β-catenin表达分布，并在骨髓移植小鼠中评价SETD2基因对MDS骨髓细胞增殖、分化及凋亡的影响。本课题将证明SETD2基因通过调控DVL3表达影响Wnt/β-catenin信号通路的活性，这为寻找MDS预后标记及治疗靶点提供实验依据。

组蛋白H3K36甲基转移酶SETD2参与骨髓增生异常综合征的发生发展。我们的前期工作发现，存在SETD2基因异常的MDS患者预后较差，并且伴有SETD2基因异常的患者骨髓CD34+细胞DVL3-mRNA及核内β-catenin蛋白表达显著增高。因此，我们假设SETD2基因通过DVL3介导Wnt/β-catenin信号通路从而影响MDS患者骨髓CD34+细胞的增殖。在本研究中，我们利用RNA-Seq技术、RT-qPCR 技术、RNA 干扰技术以及慢病毒转染技术在MDS患者骨髓细胞、SKM-1细胞系及SETD2敲除小鼠中评价了SETD2基因对CD34+骨髓细胞增殖分化的影响。本项目阐明了SETD2基因在MDS疾病进展中的重要作用和预后判断价值；证实了携带SETD2与TP53基因突变对MDS患者预后的协同作用；验证了 SETD2缺失导致Wnt/β-catenin信号通路的异常激活；提示了SETD2基因缺失影响模型小鼠CD34+巨核细胞的增殖分化。总之，本项目证实，SETD2 基因异常与 MDS疾病进展迅速以及不良预后密切相关，并且为揭示 SETD2 基因通过Wnt/β-catenin 信号通路调控骨髓CD34+细胞的具体机制提供了可靠的数据。