Background & objective: Astrocytoma has the trend of malignant progression. Differentiation-inducing therapy can induce tumor differentiation and make tumor cells become less malignant or even normal. This study was to investigate the impact of all-trans retinoic acid (ATRA) on the gene expression profile of glioblastoma cell line SHG-44, and to provide basic data for further research on gene therapy for human astrocytoma.
Methods: After treatment of 10 micromol/L ATRA, total RNA was extracted from SHG-44 cells for reverse transcription-polymerase chain reaction, and cDNA product was marked with fluorochromes Cy3 and Cy5. The gene expression profiles of SHG-44 cells before and after treatment of ATRA were detected by chip hybridization to identify differentially expressed genes. Some differentially expressed genes were selected randomly for Northern blot analysis.
Results: Forty-two differentially expressed genes were found by cDNA microarray: 28 were up-regulated and 14 were down-regulated in ATRA-treated SHG-44 cells as compared with those in untreated SHG-44 cells. These genes were functionally classified into several groups as follow: apoptosis, cell mobility and metastasis, cell cycle and growth regulation, cytoskeleton, differentiation, metabolic pathway, oncogene, oxidative phosphorylation, receptors and signal transduction, ribosome, ubiquitin-proteasome system, growth factor and cytokine, and so on.
Conclusions: ATRA can result in the changes of gene expression profiles in SHG-44 cells. These differentially expressed genes may mediate the mechanism of ATRA-induced differentiation of SHG-44 cells, and regulate tumor progression.