Evaluation of Tumor Regulatory Genes and Apoptotic Pathways in The Cytotoxic Effect of Cytochalasin H on Malignant Human Glioma Cell Line (U87MG)

OBJECTIVE: The aim of current study was to provide a proof-of-concept on the mechanism of PLAU and PCDH10 gene expressions and caspases-3, -8, and -9 activities in the apoptotic pathway after treatment of malignant human glioma cell line (U87MG) with cytochalasin H. MATERIALS AND METHODS: In the present experimental study, we have examined cytochalasin H cytotoxic activities as a new therapeutic agent on U87MG cells in vitro for the first time. The cells were cultured and treated with 10(-5)-10(-9)M of cytochalasin H for 24, 48 and 72 hours. The assessment of cell viability was carried out by (3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazoliumbromide (MTT) assay at 578 nm. The data are the average of three independent tests. mRNA expression changes of PLAU and PCDH10 were then evaluated by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). The fluorometric of caspases-3, -8, and -9 activities were carried out. The morphology changes in the U87MG cells were observed by fluorescence microscope. RESULTS: MTT assay showed that cytochalasin H (10(-5) M) inhibited the U87MG cancer cells proliferation after 48 hours. Analysis of qRT-PCR showed that the PLAU expression was significantly decreased in comparison with the control (P<0.05). The expression of PCDH10 also showed a significant increase when compared to the control (P<0.001). Fluorescence microscope indicated morphological changes due to apoptosis in U87MG cancer cells, after treatment with cytochalasin H (10-5M, 48 hours). The fluorometric evaluation of caspase-3, -8, and -9 activities showed no significant difference between the caspases and the control group. CONCLUSION: This study shows the effect of caspase-independent pathways of the programmed cell death on the U87MG cancer cell line under cytochalasin H treatment. Further studies are needed to explore the exact mechanism.