title: Verification of TREX1 as a promising indicator of judging the prognosis of osteosarcoma.
abstract: BACKGROUND
  The study aimed to explore the correlation between the expression of TREX1 and the metastasis and the survival time of patients with osteosarcoma as well as biological characteristics of osteosarcoma cells for the prognosis judgment of osteosarcoma.
  
  
  METHODS
  The correlation between the expression of TREX1 protein and the occurrence of pulmonary metastasis in 45 cases of osteosarcoma was analyzed. The CD133+and CD133-cell subsets of osteosarcoma stem cells were sorted by the flow cytometry. The tumorsphere culture, clone formation, growth curve, osteogenic and adipogenic differentiation, tumor-formation ability in nude mice, sensitivity of chemotherapeutic drugs, and other cytobiology behaviors were compared between the cell subsets in two groups; the expressions of stem cell-related genes Nanog and Oct4 were compared; The expressions of TREX1 protein and mRNA were compared between the cell subsets in two groups. The data was statistically analyzed. The measurement data between the two groups were compared using t test. The count data between the two groups were compared using χ2test and Kaplan-Meier survival analysis. A P value <0.05 indicated that the difference was statistically significant.
  
  
  RESULTS
  The expression of TREX1 protein in patients with osteosarcoma in the metastasis group was significantly lower than that in the non-metastasis group. The difference was statistically significant (P < 0.05). Up to the last follow-up visit, the former average survival time was significantly lower than that of the latter, and the difference was statistically significant (P < 0.05). The expression of TREX1 in human osteosarcoma CD133+cell subsets was significantly lower than that in CD133-cell subsets. Stemness-related genes Nanog and Oct4 were highly expressed in human osteosarcoma CD133+cell subsets with lower expression of TREX1; the biological characteristics identification experiment showed that human CD133+cell subsets with low TREX1 expression could form tumorspheres, the number of colony forming was more, the cell proliferation ability was strong, the osteogenic and adipogenic differentiation potential was big, the tumor-forming ability in nude mice was strong, and the sensibility of chemotherapeutics drugs on cisplatin was low.
  
  
  CONCLUSIONS
  The expression of TREX1 may be related to metastasis in patients with osteosarcoma. The expression of TREX1 was closely related to the cytobiology characteristics of osteosarcoma stem cell. TREX1 can play an important role in the occurrence and development processes. And, TREX1 is expected to become an effective new index for the evaluation of the prognosis.
authors.affiliation: Department of Central Laboratory, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.
authors.forename: Jinyi
authors.initials: J
authors.lastname: Feng
authors.affiliation: Department of Central Laboratory, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.|Fujian Key Laboratory of Radiation Biology, Fujian Medical University, Fuzhou, Fujian, China.|Fujian Key Laboratory of Individualized Active Immunotherapy, Fujian Medical University, Fuzhou, Fujian, China.
authors.forename: Ruilong
authors.initials: R
authors.lastname: Lan
authors.affiliation: Department of Central Laboratory, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.
authors.forename: Guanxiong
authors.initials: G
authors.lastname: Cai
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.
authors.forename: Jinluan
authors.initials: J
authors.lastname: Lin
authors.affiliation: Department of Central Laboratory, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.
authors.forename: Xinwen
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Central Laboratory, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China. jhlin_fyyy@126.com.|Department of Orthopaedics, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China. jhlin_fyyy@126.com.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Lin
authors.affiliation: Department of Central Laboratory, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China. hdp20012004@163.com.
authors.forename: Deping
authors.initials: D
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000378:metabolism* / Q000401:mortality; D045744:Cell Line, Tumor; D002648:Child; D015331:Cohort Studies; D005090:Exodeoxyribonucleases / Q000096:biosynthesis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D012516:Osteosarcoma / Q000175:diagnosis* / Q000378:metabolism* / Q000401:mortality; D010750:Phosphoproteins / Q000096:biosynthesis*; D011379:Prognosis; D015996:Survival Rate / Q000639:trends; D023041:Xenograft Model Antitumor Assays / Q000379:methods; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D010750:Phosphoproteins; D005090:Exodeoxyribonucleases; C429526:three prime repair exonuclease 1
keywords: CD133; Osteosarcoma; Prognosis evaluation; TREX1; Tumor stem cells