Low concentration of β-elemene promoted the senescence of DBTRG-05MG glioma cells. (A) Representative images of SA-β-Gal staining of DBTRG-05MG cells treated with control or 10 μg/mL β-elemene for 2 d. (B) Quantification of the percentage of SA-β-Gal+ C6 cells over total cells as shown in (A) (n=15). (C-H) qPCR analysis of p16 (C, n=4), p21 (D, n=4) and p53 (E, n=5), IL-1 (F, n=3), IL-6 (G, n=5) and NF-κB (H, n=4) mRNA levels in C6 cells treated with control or 10 μg/mL β-elemene for 2 days. Scale bar, 20 μm. Data were mean ± s.e.m. *P < 0.05, **P < 0.01, ***P < 0.001.