β-arrestin 1 transfection induced cell death in high grade glioma in vitro

The best known functions of β-arrestins (β-arr) are to regulate G protein-coupled receptors (GPCR) signaling through receptor desensitization and internalization. Many reports also suggest that β-arrs play important role in immune regulation and inflammatory responses, under physiological and pathological conditions. Recent studies have shown that β-arr 1 silencing halts proliferation and increases temozolomide (TMZ) response in glioblastoma (GBM) cells. The focus of this paper is to analyze the role of β-arr 1 overexpression in the 18 high grade glioma (HGG) cell line in terms of viability and their response to TMZ treatment. For this reason, the cell line was transfected with β-arr 1 and the effect was analyzed after 24 h, 48 h and 72 h in terms of proliferation and treatment response. We observed that β-arr 1 overexpression induced a time and dose dependant inhibition in the HGG cells. Unexpectedly, β-arr transfection resulted in a very mild increase in TMZ toxicity after 24 h, becoming non-statistically significant at 72 h. In conclusion, we showed that β-arr 1 overexpression inhibits cell proliferation in the 18 cell line but only has a very modest effect on treatment response with the alkylating agent TMZ.