Upregulation of B7-H4 promotes tumor progression of intrahepatic cholangiocarcinoma

作者:Xie, Nan; Cai, Jia-Bin; Zhang, Lu; Zhang, Peng-Fei; Shen, Ying-Hao; Yang, Xuan; Lu, Jia-Cheng; Gao, Dong-Mei; Kang, Qiang; Liu, Li-Xin; Zhang, Chi; Huang, Xiao-Yong; Zou, Hao; Zhang, Xin-Yu; Song, Zheng-Ji; Sun, Hai-Xiang; Fu, Bi-Mang*; Ke, Ai-Wu*; Shi, Guo-Ming*
来源:Cell Death & Disease, 2017, 8(12): 3205.
DOI:10.1038/s41419-017-0015-6

摘要

Recent reports show that B7-H4 is highly expressed in a variety of tumor cells, functions as a negative regulator of T cells and then promotes tumor progression. However, its expression and role in intrahepatic cholangiocarcinoma (ICC) remain unclear. In present study, B7-H4 expression in ICC and peritumoral tissues was determined at the level of mRNA and protein, and its bioactivity in ICC cells was studied after modification of B7-H4 expression. Then, the mechanism related to tumor progression induced by B7-H4 expression in ICC cells was explored. Finally, clinical significance of B7-H4 expression in ICC patients was further analyzed. The results showed that B7-H4 expression in ICC was much higher than that in peritumoral tissues at the level of both mRNA and protein. The high level of B7-H4 in ICC cells induced epithelial-to-mesenchymal transitions and promoted invasion and metastasis of tumor cells through activation of ERK1/2 signaling. The elevated B7-H4 expression was associated with the downregulated Bax, upregulated Bcl-2 expression, and activation of caspase-3. Clinically, high B7-H4 expression in tumor samples was significantly related to malignant phenotype, such as lymph node metastasis, high tumor stage, and poor differentiation. ICC patients with high expression of B7-H4 had shorter overall survival (OS) and disease-free survival Moreover, the B7-H4 expression was an independent prognostic factor for predicting OS and tumor recurrence of ICC patients after operation. In conclusion, high expression of B7-H4 promotes tumor progression of ICC and may be a novel therapeutic target for ICC patients.