0 Citations
0 Reads
A novel enhancer regulates MGMT expression and promotes temozolomide resistance in glioblastoma
Chen Xiaoyue
Zhang Minjie
Gan Haiyun
Wang Heping
Lee Jeong Heon
Fang Dong
Kitange Gaspar J
He Lihong
Hu Zeng
Parney Ian F
Meyer Fredric B
Giannini Caterina
Sarkaria Jann N
Zhang Zhiguo
Nature Communications, 2018, 9(1): 2949.
Summary
Temozolomide (TMZ) was used for the treatment of glioblastoma (GBM) for over a decade, but its treatment benefits are limited by acquired resistance, a process that remains incompletely understood. Here we report that an enhancer, located between the promoters of marker of proliferation Ki67 (MKI67) and O6-methylguanine-DNA-methyltransferase (MGMT) genes, is activated in TMZ-resistant patient-derived xenograft (PDX) lines and recurrent tumor samples. Activation of the enhancer correlates with increased MGMT expression, a major known mechanism for TMZ resistance. We show that forced activation of the enhancer in cell lines with low MGMT expression results in elevated MGMT expression. Deletion of this enhancer in cell lines with high MGMT expression leads to a dramatic reduction of MGMT and a lesser extent of Ki67 expression, increased TMZ sensitivity, and impaired proliferation. Together, these studies uncover a mechanism that regulates MGMT expression, confers TMZ resistance, and potentially regulates tumor proliferation.
Keywords
--
Select Groups
Select Contacts
swap_vert Order by date
Order by date Order by name