title: Soluble purified recombinant C2ORF40 protein inhibits tumor cell growthin vivoby decreasing telomerase activity in esophageal squamous cell carcinoma.
abstract: The chromosome 2 open reading frame 40 (C2ORF40) gene is a candidate tumor suppressor gene for a variety of tumors. Previous results by the present authors revealed that the C2ORF40 protein is a secreted protein. However, the exact biological function of secreted C2ORF40 protein in carcinogenesis has not been thoroughly investigated. In the present study, the signal peptide sequence of theC2ORF40cDNA was initially removed to produce secreted recombinant human C2ORF40 protein (rhC2ORF40). Soluble rhC2ORF40 was successfully expressed and purified, which was evaluated for the first time, to the best of our knowledge, for tumor-suppressing functionin vivoin esophageal cancer. The present results revealed that soluble purified rhC2ORF40 was concentrated with a purity of >95%. Furthermore, rhC2ORF40 inhibited esophageal cancer cell growthin vivoin a dose-dependent manner compared with a control group (P<0.05). In addition, the present study demonstrated for the first time that rhC2ORF40 decreased telomerase activity using telomeric repeat amplification protocol-enzyme-linked immunosorbent assay (P<0.05), without affecting the expression levels of telomerase-component RNA (P>0.05), as shown with polymerase chain reaction. Overall, the present results demonstrated that soluble rhC2ORF40 inhibited tumor cell growthin vivoby decreasing telomerase activity in esophageal squamous cell carcinoma. Therefore, soluble rhC2ORF40 with a high purity and biological activity may be a potential biological therapy drug for esophageal cancer.
authors.affiliation: Oncology Department, Zhengzhou University People's Hospital (Henan Provincial People's Hospital), Zhengzhou, Henan 450003, P.R. China.
authors.forename: Linwei
authors.initials: L
authors.lastname: Li
authors.affiliation: Oncology Department, Zhengzhou University People's Hospital (Henan Provincial People's Hospital), Zhengzhou, Henan 450003, P.R. China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Li
authors.affiliation: Oncology Department, Zhengzhou University People's Hospital (Henan Provincial People's Hospital), Zhengzhou, Henan 450003, P.R. China.
authors.forename: Wenyu
authors.initials: W
authors.lastname: Wang
authors.affiliation: Oncology Department, Zhengzhou University People's Hospital (Henan Provincial People's Hospital), Zhengzhou, Henan 450003, P.R. China.
authors.forename: Tianhui
authors.initials: T
authors.lastname: Gao
authors.affiliation: Oncology Department, Zhengzhou University People's Hospital (Henan Provincial People's Hospital), Zhengzhou, Henan 450003, P.R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Molecular Oncology and Department of Etiology and Carcinogenesis, Cancer Institute & Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100021, P.R. China.
authors.forename: Shixin
authors.initials: S
authors.lastname: Lu
keywords: biological therapy; esophageal cancer; rhC2ORF40; telomerase; tumor growth