Mitochondrial transcription factor a (TFAM) is upregulated in glioma

Abstract

Mitochondrial transcription factor A (TFAM), which was initially discovered as a transcription factor for mitochondrial DNA, has known to be critical for the regulation of mitochondrial DNA. However the possible involvement of TFAM in cancer is largely unknown. In this study, we have provided some evidence that TFAM may have a potential role in brain tumor. Western blot analysis with anti-TFAM antibody indicated that TFAM is overexpressed in glioblastoma cell lines including U87MG and U251MG. Transcriptome profiling of U87MG and U251MG cells by using deep-sequencing revealed that TFAM transcripts were upregulated in these cells compared to its of cerebral cortex. Confocal microscopic analysis of U251MG cells with anti-TFAM antibody showed that TFAM is located to the dot-like structure close to nucleus, probably mitochondria and endosome. Immunohistochemical analysis of glioma tissue specimens indicated that TFAM is highly upregulated. Bioinformatical analysis with Rembrandt knowledgebase also supported that TFAM mRNA is upregulated in glioma patients. Taken together, the results presented in this study obviously provided the evidence that TFAM was upregulated in glioma cell line and glioma tissue specimens. Therefore TFAM may be a novel diagnostic marker and therapeutic target for glioma and other cancer.