Upregulation of Neural Precursor Cell Expressed Developmentally Downregulated 4-1 is Associated with Poor Prognosis and Chemoresistance in Lung Adenocarcinoma.
Upregulation of Neural Precursor Cell Expressed Developmentally Downregulated 4-1 is Associated with Poor Prognosis and Chemoresistance in Lung Adenocarcinoma.
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DOI：
10.4103/0366-6999.221262
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发表时间：
2018-01-05
影响因子：
6.1
通讯作者：
Lin XY
中科院分区：
文献类型：
--
作者：
Song YH;Zhang CQ;Chen FF;Lin XY
E3泛素连接酶神经前体细胞表达发育下调的4-1(NEDD4-1)，通过多泛素化和蛋白降解，负性调节10号染色体缺失的磷酸酶和张力蛋白同源蛋白(PTEN)的蛋白水平，但其在肺癌中的意义尚不清楚。本研究探讨NEDD4-1在肺腺癌(ADC)中的表达及其在肿瘤发生和化疗敏感性中的作用。我们采用免疫组织化学方法，对135例ADC及其癌旁组织中NEDD4-1、PTEN和p-Akt蛋白的表达及意义进行了回顾性研究。此外，我们还评估了NEDD4-1的表达与临床病理特征和预后的关系。用3-(4，5-二甲基噻唑-2-基)-5-(3-羧甲氧基苯基)-2-(4-磺基苯基)-2H-四氮唑盐比色法检测了针对NEDD4-1的小干扰RNA对A549细胞增殖和化疗敏感性的影响。Transwell法检测A549细胞的迁移和侵袭能力。采用逆转录定量聚合酶链式反应和Western blotting检测NEDD4-1、PTEN、PI3K/Akt及其下游靶蛋白的表达。肺ADC组织中NEDD4-1蛋白表达明显上调，而正常肺上皮细胞中NEDD4-1蛋白表达弱或阴性。NEDD4-1在ADC中的表达(78.5%，106/135)显著高于癌旁正常肺组织(13.3%，29/135，P<；0.01)，且与淋巴结转移、TNM分期和化疗耐药有关。肺癌组织中PTEN的表达下调(60.7%vs.100.0%，P=0.007)，且与淋巴结转移、组织学类型、临床分期、化疗耐药呈负相关。P-Akt在ADC组织中的表达(71.1%，96/135)明显高于癌旁肺上皮细胞(6.7%，9/135，P<；0.01)。Kaplan-Meier和多因素分析显示，NEDD4-1和PTEN的表达均是影响肺ADC患者生存的独立危险因素。体内NEDD4-1基因敲除减少了A549细胞的增殖、迁移和侵袭，并提高了对顺铂和紫杉醇的化疗敏感性。NEDD4-1基因敲除可显著增强PTEN的表达，抑制p-Akt活性和下游靶蛋白的表达。NEDD4-1表达上调可能参与了肺ADC的进展。NEDD4-1可能通过PI3K/Akt通路调节肺ADC细胞的增殖、侵袭、迁移和化疗耐药，提示NEDD4-1可能成为治疗肺ADC的靶点。
The E3 ubiquitin ligase neural precursor cell expressed developmentally downregulated 4-1 (NEDD4-1) negatively regulates phosphatase and tensin homolog deleted on chromosome 10 (PTEN) protein levels through polyubiquitination and proteolysis, but its significance in lung cancer is still unclear. This study investigated the expression and the role of NEDD4-1 in tumor development and chemosensitivity of lung adenocarcinoma (ADC). We retrospectively investigated the expression and significance of NEDD4-1, PTEN, and p-Akt proteins in 135 paired ADC and adjacent noncancerous tissue specimens using immunohistochemistry. Furthermore, we evaluated the relationship between NEDD4-1 expression and clinicopathologic characteristics and prognosis. The effects of small interfering RNA against NEDD4-1 on proliferation and chemosensitivity were examined in A549 cells in vitro using 3-(4,5-dimethylthiazol-2-yl) -5-(3-carboxymethoxyphenyl) -2-(4-sulfophenyl)- 2H-tetrazolium method. The ability of migration and invasion of A549 cells was tested by transwell assay. Moreover, reverse-transcription quantitative polymerase chain reaction and Western blotting analyses were used to determine the expression of NEDD4-1, PTEN, phosphoinositide 3-kinase (PI3K)/Akt activity, and its downstream target proteins. NEDD4-1 protein was significantly upregulated in lung ADC tissues, whereas it was weak or negative in normal lung epithelial cells. The expression of NEDD4-1 in ADC (78.5%, 106/135) was significantly much higher than that in adjacent normal lung tissue (13.3%, 29/135, P < 0.01), and it was associated with lymph node metastasis, tumor-node-metastasis (TNM) stage, and chemotherapy resistance. PTEN expression was downregulated in lung ADC (60.7% vs. 100.0% in noncancerous specimens, P = 0.007), and was negatively correlated with lymph node metastasis, histological variants, clinical stage, chemoresistance. In addition, expression of p-Akt in ADC tissues (71.1% 96/135) was much higher than that in adjacent lung epithelial cells (6.7%, 9/135, P < 0.01). Kaplan-Meier and multivariate analysis demonstrated that expressions of NEDD4-1 and PTEN were both independent risk factors for survival in patients with lung ADC. NEDD4-1 knockdown in vivo decreased proliferation, migration, and invasion and improved chemosensitivity to cisplatin and paclitaxel in A549 cells. NEDD4-1 knockdown also significantly enhanced PTEN expression and inhibited p-Akt activity and downstream target proteins. NEDD4-1 upregulation may contribute to the progression of lung ADC. NEDD4-1 may regulate the proliferation, invasion, migration, and chemoresistance of lung ADC cells through the PI3K/Akt pathway, suggesting that it may be regarded as a therapeutic target for the treatment of lung ADC.