METHODS: ATXN3 was screened from differentially-upregulated genes of GSE71989, GSE27890 and GSE40098 datasets. The mRNA and protein levels of ATXN3 was evaluated in pancreatic cancer samples and cell lines. Through the gain- and loss-of-function experiments, the effects of ATXN3 on cell proliferation, migration and invasion were evaluated using cell counting kit-8 (CCK-8), 5-ethynyl-2\'-deoxyuridine (EdU) staining, wound healing and Transwell assays. Subsequently, the interaction between ATXN3 and HDAC6 was confirmed using double immunofluorescence staining, co-immunoprecipitation (co-IP) and proximity ligation assay (PLA). The underlying mechanism of ATXN3 was determined by knockdown of HDAC6 in ATXN3-upregulated pancreatic cancer cells. The function of ATXN3 in vivo was verified through xenograft assay.
RESULTS: High expression of ATXN3 was found in pancreatic cancer tissues. Increased ATXN3 expression dramatically promoted cell proliferation, migration, and invasion. The malignant phenotypes were suppressed in ATXN3-silenced pancreatic cancer cells. ATXN3 was proved to interact with HDAC6 and regulate its degradation through deubiquitination. Downregulation of HDAC6 inhibited ATXN3-induced development of pancreatic cancer cells through regulating the expression of PCNA, vimentin and E-cadherin. ATXN3 facilitated tumor growth of pancreatic cancer and increased HDAC6 expression in vivo.
CONCLUSIONS: This study confirmed that ATXN3 facilitated malignant phenotypes of pancreatic cancer via reducing the ubiquitination of HDAC6.
方法:从GSE71989、GSE27890和GSE40098数据集的差异上调基因中筛选ATXN3。在胰腺癌样品和细胞系中评估ATXN3的mRNA和蛋白质水平。通过功能的增益和损失实验,ATXN3对细胞增殖的影响,使用细胞计数试剂盒-8(CCK-8)评估迁移和侵袭,5-乙炔基-2'-脱氧尿苷(EdU)染色,伤口愈合和Transwell分析。随后,使用双重免疫荧光染色证实了ATXN3和HDAC6之间的相互作用,共免疫沉淀(co-IP)和邻近连接测定(PLA)。ATXN3的潜在机制是通过敲低ATXN3上调的胰腺癌细胞中的HDAC6来确定的。通过异种移植实验验证了ATXN3在体内的功能。
结果:在胰腺癌组织中发现ATXN3高表达。增加ATXN3表达显著促进细胞增殖,迁移,和入侵。ATXN3沉默的胰腺癌细胞中的恶性表型受到抑制。ATXN3被证明与HDAC6相互作用并通过去泛素化调节其降解。HDAC6下调通过调节PCNA的表达抑制ATXN3诱导的胰腺癌细胞的发展,波形蛋白和E-钙粘蛋白。ATXN3促进胰腺癌的肿瘤生长并在体内增加HDAC6表达。
结论:本研究证实ATXN3通过降低HDAC6的泛素化来促进胰腺癌的恶性表型。