Abstract：OBJECTIVE: Human telomerase reverse transcriptase (hTERT) is a rate-limiting enzyme which dictates the activity of human telomerase and thus decides the life span of cells. The aim of this study was to explore the expression of hTERT in bone marrow from children with β-thalassemia major and the relationship between the expression of hTERT and hemoglobin levels. METHODS: Multiple allele specific polymerase chain reaction (MASPCR) was used for targeted DNA amplification and gene mutation analysis of β-thalassemia. hTERT mRNA expression in bone marrow was examined using real-time reverse transcription polymerase chain reaction (RT-PCR) analysis in 29 children with β-thalassemia major, in 10 children with agranulocytosis and in K562 cell line. The hemoglobin levels in peripheral blood were measured. The relationship between hTERT expression and hemoglobin levels was evaluated by the Spearman test in the β-thalassemia major group. RESULTS: hTERT mRNA expression significantly increased in bone marrow from children with β-thalassemia major compared with that from children with agranulocytosis (0.2928±0.0838 vs 0.0993±0.0336; P<0.01), but was significantly lower than that in K562 cell line (0.8291±0.0908) (P<0.01). A significantly inverse correlation was found between hTERT mRNA expression and hemoglobin levels (r=-0.841, P<0.01). CONCLUSIONS: A low hemoglobin concentration might contribute to the up-regulation of marrow hTERT expression in children with β-thalassemia major.［Chin J Contemp Pediatr, 2009, 11 (6):449-452］
［1］Kim CM, Oh YJ, Cho SH, Chung DJ, Hwang JY, Park KH, et al. Increased telomerase activity and human telomerase reverse transcriptase mRNA expression in the endometrium of patients with endometriosis［J］．Hum Reprod, 2007, 22(3)：843-849．
［2］Zhou C, Bae-Jump VL, Whang YE, Whang YE, Gehrig PA, Boggess JF. The PTEN tumor suppressor inhibits telomerase activity in endometrial cancer cells by decreasing hTERT mRNA levels［J］．Gynecol Oncol, 2006, 101(2)：305-310．
［3］Terrin L, Trentin L, Degan M, Corradini I, Bertorelle R, Carli P, et al. Telomerase expression in B-cell chronic lymphocytic leukemia predicts survival and delineates subgroups of patients with the same igVH mutation status and different outcome［J］．Leukemia, 2007, 21(5)：965-972．
［4］Nowak T, Januszkiewicz D, Zawada M, Pernak M, Lewandowski K, Rembowska J, et al. Amplification of hTERT and hTERC genes in leukemic cells with high expression and activity of telomerase［J］. Oncol Rep, 2006, 16(2):301-305．
［5］Wang PH, Chen GD, Chang H, Yang SF, Han CP, Lin LY, et al. High expression of human telomerase reverse transcriptase in high-grade intraepithelial neoplasia and carcinoma of uterine cervix and its correlation with human papillomavirus infection［J］．Reproductive Science, 2007, 14(4)：338-348．
［6］Lantuejoul S, Soria JC, Moro-Sibilot D, Morat L, Veyrenc S, Lorimier P, et al. Differential expression of telomerase reverse transcriptase (hTERT) in lung tumours［J］．Br J Cancer, 2004, 90(6):1222-1229.
［7］Zimmermann S, Glaser S, Ketteler R, Waller CF, Klingmüller U, Martens UM. Effects of telomerase modulation in human hematopoietic progenitor cells［J］．Stem Cells, 2004, 22(5)：741-749．
［8］Abdallah BM, Haack-Sorensen M, Burns JS, Elsnab B, Jakob F, Hokland P, et al．Maintenance of differentiation potential of human bone marrow mesenchymal stem cells immortalized by human telomerase reverse transcriptase gene despite ［corrected］ extensive proliferation［J］．Biochem Biophys Res Commun, 2005, 326(3)：527-538．
［9］Li XH, Qu Y, Mao M, Yu F, Li Q, Hua YM, et al．Expression of human telomerase reverse transcriptase in bone marrow CD34+ cells from patients with β-thalassemia major［J］．Transfusion, 2008, 48(8)：1627-1633．
［12］Wang SL, Chen WT, Li SH, Li SW, Yang SF, Chai CY．Expression of human telomerase reverse transcriptase and cyclin-D1 in olfactory neuroblastoma［J］．APMIS, 2007, 115(1)：17-21．
［13］Izadpanah R, Trygg C, Patel B, Kriedt C, Dufour J, Gimble JM, et al．Biologic properties of mesenchymal stem cells derived from bone marrow and adipose tissue［J］．J Cell Biochem, 2006, 99(5)：1285-1297．
［14］Yanada S, Ochi M, Kojima K, Sharman P, Yasunaga Y, Hiyama E．Possibility of selection of chondrogenic progenitor cells by telomere length in FGF-2-expanded mesenchymal［J］. Cell Prolif, 2006, 39(6)：575-584．
［15］Brummendorf TH, Balabanov S．Telomere length dynamics in normal hematopoiesis and in disease states characterized by increased stem cell［J］．Leukemia, 2006, 20(10)：1706-1716．
［16］Gammaitoni L, Weisel KC, Gunetti M, Wu KD, Bruno S, Pinelli S, et al．Elevated telomerase activity and minimal telomere loss in cord blood long-term cultures with extensive stem cell replication［J］．Blood, 2004, 103(12)：4440-4448．
［17］Wright WE, Shay JW．Telomere biology in aging and cancer［J］．J Am Geriatr Soc, 2005, 53(9s)：S292-S294．
