PADI3 induces cell cycle arrest via the Sirt2/AKT/p21 pathway and acts as a tumor suppressor gene in colon cancer
PADI3 induces cell cycle arrest via the Sirt2/AKT/p21 pathway and acts as a tumor suppressor gene in colon cancer
复制标题
PADI3 通过 Sirt2/AKT/p21 途径诱导细胞周期停滞，并在结肠癌中充当肿瘤抑制基因
DOI：
10.20892/j.issn.2095-3941.2019.0065
复制
发表时间：
2019-11-01
影响因子：
5.5
通讯作者：
Liu, Chunyan
中科院分区：
文献类型：
--
作者：
Chang, Xiaotian;Chai, Zhengbin;Liu, Chunyan
目的PADI3作为肽基精氨酸脱亚胺酶（PAD）家族的一员，在结肠癌组织中表达较弱，在结肠癌邻近组织中表达较高。然而，PADI3在结肠癌中的作用尚不清楚。在这项研究中，我们探讨了PADI3在结肠癌肿瘤发生中的功能和分子机制。方法采用Western blot和real-time PCR检测多种基因的表达水平。采用CCK-8、流式细胞术（FCM）和集落形成实验检测细胞增殖、细胞周期和集落形成能力。采用rna测序方法研究PADI3在肿瘤发生中的分子机制。通过截断突变实验确定PADI3的关键功能域。结果PADI3过表达抑制细胞增殖和集落形成，导致HCT116（原发结肠癌）和LoVo（转移性结肠癌结节）细胞G1期阻滞。与对照细胞相比，表达padi3的HCT116细胞的肿瘤形成率更低，肿瘤体积更小。PADI3显著降低Sirtuin2 （Sirt2）和Snail的表达以及AKT磷酸化，增加p21的表达，Sirt2过表达部分逆转了PADI3过表达诱导的作用。免疫细胞化学显示PADI3主要定位于细胞质中。截断突变实验表明，c结构域是参与PADI3抗肿瘤活性的关键结构域。结论PADI3通过下调细胞质中Sirt2的表达，抑制Snail的表达和AKT的磷酸化，促进p21的表达，c结构域是其抗肿瘤活性的关键结构域。
Objective As a member of the peptidyl arginine deiminase (PAD) family, PADI3 is weakly expressed in colon cancer tissues and highly expressed in adjacent colon cancer tissues. However, the role of PADI3 in colon cancer is unclear. In this study, we investigated the function and molecular mechanism of PADI3 in colon cancer tumorigenesis. Methods Western blot and real-time PCR were used to detect the expression levels of several genes. CCK-8, flow cytometry (FCM) and colony formation assays were used to examine cell proliferation, the cell cycle and colony formation ability. RNA-sequencing analysis was used to study the molecular mechanism of PADI3 in tumorigenesis. A truncation mutation experiment was performed to determine the key functional domain of PADI3. Results PADI3 overexpression inhibited cell proliferation and colony formation and led to G1 phase arrest in both HCT116 (originating from primary colon cancer) and LoVo (originating from metastatic tumor nodules of colon cancer) cells. PADI3-expressing HCT116 cells had a lower tumor formation rate and produced smaller tumors than control cells. PADI3 significantly decreased Sirtuin2 (Sirt2) and Snail expression and AKT phosphorylation and increased p21 expression, and Sirt2 overexpression partly reversed the effects induced by PADI3 overexpression. Immunocytochemistry showed that PADI3 is mainly localized in the cytoplasm. Truncation mutation experiments showed that the C-domain is the key domain involved in the antitumor activity of PADI3. Conclusions PADI3 suppresses Snail expression and AKT phosphorylation and promotes p21 expression by downregulating Sirt2 expression in the cytoplasm, and the C-domain is the key domain for its antitumor activity.