Mitogen-Activated Protein Kinase Kinase Kinase 4 Deficiency in Intrahepatic Cholangiocarcinoma Leads to Invasive Growth and Epithelial-Mesenchymal Transition
Mitogen-Activated Protein Kinase Kinase Kinase 4 Deficiency in Intrahepatic Cholangiocarcinoma Leads to Invasive Growth and Epithelial-Mesenchymal Transition
复制标题
肝内胆管癌中丝裂原激活蛋白激酶激酶激酶 4 缺陷导致侵袭性生长和上皮-间质转化
作者：
Yang Liu-Xiao;Gao Qiang;Shi Jie-Yi;Wang Zhi-Chao;Zhang Yong;Gao Ping-Ting;Wang Xiao-Ying;Shi Ying-Hong;Ke Ai-Wu;Shi Guo-Ming;Cai Jia-Bin;Liu Wei-Ren;Duan Meng;Zhao Ying-Jun;Ji Yuan;Gao Dong-Mei;Zhu Kai;Zhou Jian;Qiu Shuang-Jian;Cao Ya;Tang Qi-Qun;Fan Jia
肝内胆管细胞癌（iCCA）的分子发病机制知之甚少，其发病率在全球范围内持续增加。据报道，丝裂原活化蛋白激酶4（MAP 3 K4）的缺乏可诱导胎盘和胚胎发育的上皮-间质转化（EMT）过程，但其在人类癌症中的作用仍不清楚。MAP 3 K4在iCCA中存在体细胞突变，因此我们对124例iCCA患者的MAP 3 K4的所有外显子进行了测序。我们在10例（8.06%）患者中发现了9个体细胞突变，尤其是在淋巴结转移和肝内转移的患者中。我们还发现，与配对的非肿瘤组织相比，iCCA中MAP 3 K4的信使RNA和蛋白水平显著降低。此外，MAP 3 K4在胆管癌细胞中的敲低显著增强了细胞的体外增殖和侵袭以及体内肿瘤的进展，伴随着典型的EMT过程。相反，MAP 3 K4在胆管癌细胞中的过表达明显逆转EMT并抑制细胞侵袭。MAP 3 K4通过拮抗p38/核因子κB/snail通路的活性，在iCCA中发挥EMT负调控作用。我们发现MAP 3 K4的肿瘤抑制作用通过失活突变而消除。临床上，一项包含322例iCCA患者样本的组织微阵列研究显示，iCCA中MAP 3 K4的低表达与侵袭性肿瘤特征（如血管浸润和肝内或淋巴结转移）呈正相关，并且与治愈性手术后生存率低和复发率增加独立相关。结论：MAP 3 K4显著下调，频繁突变，并有效调节iCCA中的EMT过程，是iCCA的假定肿瘤抑制因子。（肝病学2015;62：1804 - 1816）
The molecular pathogenesis of intrahepatic cholangiocarcinoma (iCCA) is poorly understood, and its incidence continues to increase worldwide. Deficiency of mitogen‐activated protein kinase kinase kinase 4 (MAP3K4) has been reported to induce the epithelial‐mesenchymal transition (EMT) process of placental and embryonic development, yet its role in human cancer remains unknown. MAP3K4 has somatic mutation in iCCA so we sequenced all exons of MAP3K4 in 124 iCCA patients. We identified nine somatic mutations in 10 (8.06%) patients, especially in those with lymph node metastasis and intrahepatic metastasis. We also showed that messenger RNA and protein levels of MAP3K4 were significantly reduced in iCCA versus paired nontumor tissues. Furthermore, knockdown of MAP3K4 in cholangiocarcinoma cells markedly enhanced cell proliferation and invasivenessin vitroand tumor progressionin vivo, accompanied by a typical EMT process. In contrast, overexpression of MAP3K4 in cholangiocarcinoma cells obviously reversed EMT and inhibited cell invasion. Mechanistically, MAP3K4 functioned as a negative regulator of EMT in iCCA by antagonizing the activity of the p38/nuclear factor κB/snail pathway. We found that the tumor‐inhibitory effect of MAP3K4 was abolished by inactivating mutations. Clinically, a tissue microarray study containing 322 iCCA samples from patients revealed that low MAP3K4 expression in iCCA positively correlated with aggressive tumor characteristics, such as vascular invasion and intrahepatic or lymph node metastases, and was independently associated with poor survival and increased recurrence after curative surgery.Conclusions:MAP3K4, significantly down‐regulated, frequently mutated, and potently regulating the EMT process in iCCA, was a putative tumor suppressor of iCCA. (Hepatology2015;62:1804‐1816)