Cholangiocarcinoma is a deadly disease which responds poorly to surgery and conventional chemotherapy or radiotherapy. Early diagnosis is difficult due to the anatomical and biological characteristics of cholangiocarcinoma. Cyclin-dependent kinase inhibitor 1B (p27(Kip1)) is a cyclin-dependent kinase inhibitor and in the present study, we found that p27(Kip1) expression was suppressed in the nucleus and increased in the cytoplasm in 53 samples of cholangiocarcinoma from patients with highly malignant tumors (poorly-differentiated and tumor-node-metastsis (TNM) stage III-IV) compared with that in samples from 10 patients with chronic cholangitis. The expression of phosphorylated (p-)p27(Kip1) (Ser10), one of the phosphorylated forms of p27(Kip1), was increased in the patient samples with increasing malignancy and clinical stage. Coincidentally, chromosome region maintenance 1 (CRM-1; also referred to as exportin 1 or Xpo1), a critical protein responsible for protein translocation from the nucleus to the cytoplasm, was also overexpressed in the tumor samples which were poorly differentiated and of a higher clinical stage. Through specific short hairpin RNA (shRNA)-mediated knockdown of CRM-1 in the cholangiocarcinoma cell line QBC939, we identified an elevation of cytoplasmic p27(Kip1) and a decrease of nuclear p27(Kip1). Furthermore, the viability and colony formation ability of QBC939 cells was largely reduced with G1 arrest. Consistent with the findings of the in vitro experiments, in a xenograft mouse model, the tumors formed in the CRM-1 knockdown group were markedly smaller and weighed less than those in the control group in vivo. Taken together, these findings demonstrated that the interplay between CRM-1 and p27(Kip1) may provide potentially potent biomarkers and functional targets for the development of future cholangiocarcinoma treatments.
基金:
Natural Science Foundation of Hubei Province of China [2013CKB020]
第一作者单位:[1]Huazhong Univ Sci & Technol,Tongji Med Coll,Tongji Hosp,Dept Geriatr,1095 Jiefang Ave,Wuhan 430030,Hubei,Peoples R China
通讯作者:
推荐引用方式(GB/T 7714):
Luo Jian,Chen Yongjun,Li Qiang,et al.CRM-1 knockdown inhibits extrahepatic cholangiocarcinoma tumor growth by blocking the nuclear export of p27Kip1[J].INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE.2016,38(2):381-390.doi:10.3892/ijmm.2016.2628.
APA:
Luo, Jian,Chen, Yongjun,Li, Qiang,Wang, Bing,Zhou, Yanqiong&Lan, Hongzhen.(2016).CRM-1 knockdown inhibits extrahepatic cholangiocarcinoma tumor growth by blocking the nuclear export of p27Kip1.INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE,38,(2)
MLA:
Luo, Jian,et al."CRM-1 knockdown inhibits extrahepatic cholangiocarcinoma tumor growth by blocking the nuclear export of p27Kip1".INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE 38..2(2016):381-390