title: [RITA combined with temozolomide inhibits the proliferation of human glioblastoma U87 cells].
abstract: OBJECTIVE
  To observe the effect of RITA, a small molecule that targets p53, combined with temozolomide (TMZ) on proliferation, colony formation and apoptosis of human glioblastoma U87 cells and explore the underlying mechanism.
  
  
  METHODS
  Cultured U87 cells were treated with RITA (1, 5, 10, 20 µmol/L), TMZ, or RITA+TMZ (half dose) for 24, 48 or 72 h. MTS assay were used to detect the cell proliferation, and the cell proliferation rate and inhibitory rate were calculated. The effect of combined treatments was evaluated by the q value. The expressions of p53, p21 and other apoptosis-associated genes were detected by qRT-PCR and Western blotting; cell apoptosis was assayed using flow cytometry with Annexin V/PI double staining; colony formation of the cells was detected with crystal violet staining.
  
  
  RESULTS
  MTS assay showed that RITA at the 4 doses more potently inhibited U87 cell viability than TMZ at 72 h (P=0.000) with inhibitory rates of 25.94%-41.38% and 3.84%-8.20%, respectively. RITA combined with TMZ caused a more significant inhibition of U87 cells (29.21%-52.11%) than RITA (P<0.01) and TMZ (P=0.000) alone. At the doses above 5 µmol/L, the combined treatments with RITA+TMZ for 48 h resulted in q values exceeding 1.2 and showed an obvious synergistic effect of the drugs. Both RITA and TMZ, especially the latter, significantly increased the expressions of p53, p21, puma, and other apoptosis-associated genes to accelerate apoptosis and inhibit the growth and colony formation of U87 cells, and the effect was more obvious with a combined treatment.
  
  
  CONCLUSIONS
  RITA inhibits the growth of human glioblastoma cells and enhance their sensitivity to TMZ by up-regulating p53 expression, and when combined, RITA and TMZ show a synergistic effect to cause a stronger cell inhibition.
authors: Biosafety Level-3 (BSL-3) Laboratory, School of Public Health1, Department of Neurosurgery, Nanfang Hospital2, Southern Medical University, Guangzhou 510515, China. E-mail: 973429390@qq.com.
authors: Xiao-Yan
authors: XY
authors: He
authors: Xiao-Li
authors: XL
authors: Feng
authors: Xin-Pei
authors: XP
authors: Song
authors: Huan-Chao
authors: HC
authors: Zeng
authors: Zhong-Xu
authors: ZX
authors: Cao
authors: Wei-Wei
authors: WW
authors: Xiao
authors: Bao
authors: B
authors: Zhang
authors: Qing-Hua
authors: QH
authors: Wu
mesh_terms: D017209:Apoptosis; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival; D003606:Dacarbazine / Q000031:analogs & derivatives* / Q000494:pharmacology; D005663:Furans / Q000494:pharmacology*; D005909:Glioblastoma / Q000188:drug therapy*; D006801:Humans; D000077204:Temozolomide
chemical_list: D005663:Furans; C118989:NSC 652287; D003606:Dacarbazine; D000077204:Temozolomide