TY - JOUR
T1 - Mutant IDH1 expression drives TERT promoter reactivation as part of the cellular transformation process
AU - Ohba, Shigeo
AU - Mukherjee, Joydeep
AU - Johannessen, Tor Christian
AU - Mancini, Andrew
AU - Chow, Tracy T.
AU - Wood, Matthew
AU - Jones, Lindsey
AU - Mazor, Tali
AU - Marshall, Roxanne E.
AU - Viswanath, Pavithra
AU - Walsh, Kyle M.
AU - Perry, Arie
AU - Bell, Robert J.A.
AU - Phillips, Joanna J.
AU - Costello, Joseph F.
AU - Ronen, Sabrina M.
AU - Pieper, Russell O.
N1 - Publisher Copyright:
©2016 AACR.
PY - 2016/11/15
Y1 - 2016/11/15
N2 - Mutations in the isocitrate dehydrogenase gene IDH1 are common in low-grade glioma, where they result in the production of 2-hydroxyglutarate (2HG), disrupted patterns of histone methylation, and gliomagenesis. IDH1 mutations also cosegregate with mutations in the ATRX gene and the TERT promoter, suggesting that IDH mutation may drive the creation or selection of telomere-stabilizing events as part of immortalization/transformation process. To determine whether and how this may occur, we investigated the phenotype of pRb-/p53-deficient human astrocytes engineered with IDH1 wild-type (WT) or R132H-mutant (IDH1mut) genes as they progressed through their lifespan. IDH1mut expression promoted 2HG production and altered histone methylation within 20 population doublings (PD) but had no effect on telomerase expression or telomere length. Accordingly, cells expressing either IDH1WT or IDH1mut entered a telomere-induced crisis at PD 70. In contrast, only IDH1mut cells emerged from crisis, grew indefinitely in culture, and formed colonies in soft agar and tumors in vivo. Clonal populations of postcrisis IDH1mut cells displayed shared genetic alterations, but no mutations in ATRX or the TERT promoter were detected. Instead, these cells reactivated telomerase and stabilized their telomeres in association with increased histone lysine methylation (H3K4me3) and c-Myc/Max binding at the TERT promoter. Overall, these results show that although IDH1mut does not create or select for ATRX or TERT promoter mutations, it can indirectly reactivate TERT, and in doing so contribute to astrocytic immortalization and transformation.
AB - Mutations in the isocitrate dehydrogenase gene IDH1 are common in low-grade glioma, where they result in the production of 2-hydroxyglutarate (2HG), disrupted patterns of histone methylation, and gliomagenesis. IDH1 mutations also cosegregate with mutations in the ATRX gene and the TERT promoter, suggesting that IDH mutation may drive the creation or selection of telomere-stabilizing events as part of immortalization/transformation process. To determine whether and how this may occur, we investigated the phenotype of pRb-/p53-deficient human astrocytes engineered with IDH1 wild-type (WT) or R132H-mutant (IDH1mut) genes as they progressed through their lifespan. IDH1mut expression promoted 2HG production and altered histone methylation within 20 population doublings (PD) but had no effect on telomerase expression or telomere length. Accordingly, cells expressing either IDH1WT or IDH1mut entered a telomere-induced crisis at PD 70. In contrast, only IDH1mut cells emerged from crisis, grew indefinitely in culture, and formed colonies in soft agar and tumors in vivo. Clonal populations of postcrisis IDH1mut cells displayed shared genetic alterations, but no mutations in ATRX or the TERT promoter were detected. Instead, these cells reactivated telomerase and stabilized their telomeres in association with increased histone lysine methylation (H3K4me3) and c-Myc/Max binding at the TERT promoter. Overall, these results show that although IDH1mut does not create or select for ATRX or TERT promoter mutations, it can indirectly reactivate TERT, and in doing so contribute to astrocytic immortalization and transformation.
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U2 - 10.1158/0008-5472.CAN-16-0696
DO - 10.1158/0008-5472.CAN-16-0696
M3 - Article
C2 - 27758882
AN - SCOPUS:84995519548
SN - 0008-5472
VL - 76
SP - 6680
EP - 6689
JO - Cancer Research
JF - Cancer Research
IS - 22
ER -