MACF1 knockdown in glioblastoma multiforme cells increases temozolomide-induced cytotoxicity / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of microtubule-actin crosslinking factor 1 (MACF1) in the response of glioma cells to temozolomide (TMZ).</p><p><b>METHODS</b>TMZ was applied to a human gliomablastoma cell line (U87) and changes in the protein expression and cellular localization were determined with Western blot, RT-PCR, and immunofluorescence. The responses of the cells with MACF1 expression knockdown by RNA interference to TMZ were assessed. TMZ-induced effects on MACF1 expression were also assessed by immunohistochemistry in a nude mouse model bearing human glioblastoma xenografts.</p><p><b>RESULTS</b>TMZ resulted in significantly increased MACF1 expression (by about 2 folds) and changes in its localization in the gliomablastoma cells both in vitro and in vivo (P<0.01). Knockdown of MACF1 reduced the proliferation (by 45%) of human glioma cell lines treated with TMZ (P<0.01). TMZ-induced changes in MACF1 expression was accompanied by cytoskeletal rearrangement.</p><p><b>CONCLUSION</b>MACF1 may be a potential therapeutic target for glioblastoma.</p>

RNA interference of PC4 and SFRS1 interacting protein 1 inhibits invasion and migration of U87 glioma cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of small interfering RNA (siRNA)-mediated silencing of PC4 and SFRS1 interacting protein 1 (PSIP1) on invasion and migration of human glioma U87 cells.</p><p><b>METHODS</b>Chemically synthesized siRNA targeting PSIP1 gene was transfected into U87 cells via lipofectamine, and the gene silencing effect was determined using real-time PCR. The changes in the invasion and migration abilities of the transfected cells were assessed with Transwell assay and wound healing assay, respectively. Western blotting was used to analyze the expression of N-cadherin, β-catenin and the transcription factor Slug.</p><p><b>RESULTS</b>The mRNA and protein level of PSIP1 was significantly reduced in U87 cells after transfection with PSIP1 siRNA (P<0.0001). PSIP1 knockdown in U87 cells resulted in significant suppression of cell invasion and migration abilities (P<0.01) and also reduced N-cadherin, β-catenin and Slug expressions.</p><p><b>CONCLUSION</b>s Silencing of PSIP1 impairs the invasion and migration abilities of glioma cells and lowers the expressions of N-cadherin, β-catenin and Slug, suggesting that PSIP1 may regulate Slug by classical Wnt/β-catenin signaling pathway to modulate epithelial-mesenchymal transition and promote the invasion and migration of glioma cells.</p>