Signal transducer and activator of transcription 1 (STAT1) is thought to be a tumor suppressor protein. The authors investigated the expression and role of STAT1 in glioblastoma.
Immunohistochemistry was used to detect the expression of STAT1 in glioblastoma and normal brain tissues. Reverse transcription–polymerase chain reaction and Western blot analysis were used to detect mRNA and protein expression levels of STAT1. Cell growth, proliferation, migration, apoptosis, and the expression of related genes and proteins (Bcl-2, Bax, cleaved caspase-3, caspase-9, p21, and proliferating cell nuclear antigen) were examined in vitro via cell counting kit-8, wound-healing, flow cytometry, Rhodamine B, TUNEL, and Western blot assays.
Human glioblastoma had decreased expression of STAT1 proteins. Transfection of the U87MG cells with STAT1 plasmid in vitro demonstrated significant inhibition of cell growth and an increase in apoptotic cell death compared with cells transfected with vector or mock plasmids. These effects were associated with the upregulation of cleaved caspase-3, Bax, and p21 and the downregulation of Bcl-2 expression.
The results of this study suggest that increased expression of STAT1 by transfection with STAT1 plasmid synergistically inhibits human U87MG glioblastoma cell growth in vitro.
Abbreviations used in this paper:CCK-8 = cell counting kit-8; GBM = glioblastoma multiforme; OD = optical density; PCNA = proliferating cell nuclear antigen; RT-PCR = reverse transcription–polymerase chain reaction; rTdT = terminal deoxynucleotidyl transferase, recombinant; STAT = signal transducer and activator of transcription; TMZ = temozolomide.
* Mr. Dou and Dr. Zhao contributed equally to this work.
Address correspondence to: Gang Zhao, M.D., Department of Neurosurgery, First Bethune Hospital of Jilin University, Changchun 130021, Jilin Province, People's Republic of China. email: Baotoujuhaitao@yahoo.com.cn.
Please include this information when citing this paper: published online April 19, 2013; DOI: 10.3171/2013.3.JNS122051.
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