title: hTERT promoter activity identifies osteosarcoma cells with increased EMT characteristics.
abstract: Epithelial-mesenchymal transition (EMT) is a critical step in order for epithelial-derived malignancies to metastasize, however, its role in mesenchymal-derived tumors, i.e., osteosarcoma, remains unclear. Cancer stem cells (CSCs) are enriched with cells that undergo EMT. The activity of telomerase is maintained in normal stem cells and a number of malignant tumors. The current study observed the heterogeneity of telomerase activity among individual osteosarcoma cells. We hypothesized that telomerase-positive (TELpos) cells are enriched for stem cell-like and EMT properties. A human telomerase reverse transcriptase (hTERT) promoter-reporter was applied to assess the telomerase activity of individual MG63 osteosarcoma cells and sort them into TELpos and telomerase-negative (TELneg) subpopulations. It was found that the TELpos cells exhibited an enhanced ability to form sarcospheresin vitro.In addition, TELpos cells exhibited a higher expression of vimentin, accompanied by an increased long/short axis ratio. A panel of EMT-related genes was evaluated by quantitative PCR and western blot analysis, and were found to be significantly upregulated in TELpos cells. Next, thein vitromigration capacity was examined by Transwell assay, which confirmed that TELpos cells are more prone to migration (2.6 fold). The results of the present study support the concept that EMT also applies to mesenchymal-derived osteosarcoma and draws a connection between telomerase and EMT characteristics.
authors.affiliation: Department of Orthopedics, Renmin Hospital, Wuhan University, Wuhan, Hubei 430060, P.R. China.
authors.forename: Ling
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Orthopedics, Renmin Hospital, Wuhan University, Wuhan, Hubei 430060, P.R. China.
authors.forename: Shiqing
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Orthopedics, Renmin Hospital, Wuhan University, Wuhan, Hubei 430060, P.R. China.
authors.forename: Weichun
authors.initials: W
authors.lastname: Guo
authors.affiliation: Department of Orthopedics, Renmin Hospital, Wuhan University, Wuhan, Hubei 430060, P.R. China.
authors.forename: Chun
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Renmin Hospital, Wuhan University, Wuhan, Hubei 430060, P.R. China.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Opening Laboratory for Oversea Scientists, Wuhan University School of Basic Medical Science, Wuhan, Hubei 430072, P.R. China.
authors.forename: Huichao
authors.initials: H
authors.lastname: Yan
authors.affiliation: Department of Radiation Oncology, Tumor Hospital Xiangya School of Medicine of Central South University, Changsha, Hunan 410013, P.R. China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wu
keywords: epithelial-mesenchymal transition; human telomerase reverse transcriptase; osteosarcoma; telomerase