Imbalance expression of retinoblastoma protein-interacting zinc finger gene RIZ1/RIZ2 contribute to apoptosis of esophageal squamous cell carcinoma

Objective To investigate the imbalance expression of retinoblastoma protein-interacting zinc finger gene (RIZ1/RIZ2) in esophageal squamous cell carcinoma and its effect on apoptosis of esophageal squamous carcinoma cells. Methods Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect RIZ1 and RIZ1+ RIZ2 mRNA expression levels in esophageal squamous cell carcinoma tissues and normal esophageal epithelial tissues. Esophageal squamous cancer cells EC109, in which RIZ1 mRNA was not detected in our previous studies, were transfected respectively by pcDNA3.1(+ )/RIZ1 and pcDNA3.1(+ ) using the lipofectamin transfection reagent. Real-time PCR and Western blotting were used to evaluate the transfection efficiency. After successful transfection, the change of RIZ1+ RIZ2 mRNA expression level was also examined, Flow cytometry assay was used to investigate the apoptosis of the cells. Results RIZ1 gene mRNA expression level in esophageal squamous cell carcinoma tissues was lower than normal esophageal epithelial tissues (1.00 and 28.10±2.30; t=-57.758, P=0.000), While the expression level of RIZ1+ RIZ2 mRNA has no statistical differences (1.00 and 1.08±0.31; t=-1.180, P=0.249); RIZ1 gene mRNA expression levels rise (10.83±1.94 and 1.00; t=-11.308, P=0.000), While RIZ1+ RIZ2 mRNA expression levels did not change after RIZ1 was transfected successfully in EC109 (0.98±0.08 and 1.00; t=0.581, P=0.592), And the apoptosis rate of EC109 increased after transfection [(54.97±2.33)% and (38.29±8.44)%; t=-4.560, P=0.010]. Conclusion There is imbalance expression of RIZ1/RIZ2 in esophageal squamous cell carcinoma, The imbalance expression of RIZ1/RIZ2 could induce apoptosis and may contribute to the progression of esophageal squamous cell carcinoma (ESCC). Key words: Retinoblastoma protein-interacting zinc finger gene 1; Retinoblastoma protein-interacting zinc finger gene 2; Esophageal squamous cell carcinoma