Cassar Lucy, Li He, Pinto Alexander Ruvantha, Nicholls Craig, Bayne Sharyn, Liu Jun-Ping
Department of Immunology, Central Eastern Clinical School, Monash University, Melbourne, Australia.
Cancer Res. 2008 Nov 15;68(22):9157-66. doi: 10.1158/0008-5472.CAN-08-1323.
Telomere maintenance is critical in tumor cell immortalization. Here, we report that the cytokine bone morphogenetic protein-7 (BMP7) inhibits telomerase activity that is required for telomere maintenance in cervical cancer cells. Application of human recombinant BMP7 triggers a repression of the human telomerase reverse transcriptase (hTERT) gene, shortening of telomeres, and hTERT repression-dependent cervical cancer cell death. Continuous treatment of mouse xenograft tumors with BMP7, or silencing the hTERT gene, results in sustained inhibition of telomerase activity, shortening of telomeres, and tumor growth arrest. Overexpression of hTERT lengthens telomeres and blocks BMP7-induced tumor growth arrest. Thus, BMP7 negatively regulates telomere maintenance, inducing cervical tumor growth arrest by a mechanism of inducing hTERT gene repression.
端粒维持在肿瘤细胞永生化过程中至关重要。在此,我们报告细胞因子骨形态发生蛋白-7(BMP7)可抑制端粒维持所需的端粒酶活性,而端粒维持在宫颈癌细胞中是必需的。应用重组人BMP7会引发人端粒酶逆转录酶(hTERT)基因的抑制、端粒缩短以及依赖hTERT抑制的宫颈癌细胞死亡。用BMP7持续处理小鼠异种移植瘤,或使hTERT基因沉默,会导致端粒酶活性持续受到抑制、端粒缩短以及肿瘤生长停滞。hTERT的过表达会延长端粒并阻断BMP7诱导的肿瘤生长停滞。因此,BMP7通过诱导hTERT基因抑制的机制对端粒维持起负向调节作用,从而诱导宫颈肿瘤生长停滞。