KLF16 suppresses human glioma cell proliferation and tumourigenicity by targeting TFAM.

Background: This study aims to via unveiling the novel mechanisms of KLF16 in regulating expression of genes involved in glioma.

Methods: KLF16 or KLF16-siRNA was transfected to U87MG cells by lentivirus. Colony formation assay was applied for detecting cell proliferation. MTT assay was adopted to assess cell viability. TUNEL assay was selected to evaluate cell apoptosis. Flow cytometry was used to determine cell cycle. Real-time PCR was performed to test mRNA expression. Western blot was used to detect protein level. Luciferase assay was applied to confirm the regulatory relationship between KLF16 and Mitochondrial transcription factor A (TFAM). Chromatin immunoprecipitation was adopted to test the protein binding site. The nude mouse transplantation tumour experiment was selected to test cancer cell proliferation in vivo.

Results: KLF16 was decreased in glioma cells and tissues. KLF16 obviously restrained U87MG cell proliferation both in vivo and in vitro. KLF16 transfection reduced mRNA and protein levels related to cell proliferation. KLF16 targeted a putative binding site near the transcription start sites (TSSs) of TFAM gene, thus suppressing glioma cell proliferation. KLF16-siRNA exhibited the opposite impact. KLF16 presented significant negative correlation with TFAM level in glioma patients.

Conclusions: KLF16 is a key regulator of glioma cell proliferation by directly targeting TFAM.