Abstract:

Abstract:Objective To explore the mechanism of 3-methyladenine (3-MA)in promoting the sensitivity of chemotherapeutics in oral squamous cell carcinoma by observing the kill effect of cisplatin (DDP)on oral squamous cell carcinoma Tca83 cell line.Methods The Tca83 cells at logarithmic growth phase were divided into  control group,3-MA group,DDP group,3-MA+DDP group and DDP+3-MA group . The survival rate of Tca83 cells  was examined by tetrazolium bromide(MTT)colorimetry; the LC3-Ⅱ expression level was detected by laser scanning confocal microscope;the apoptotic rate was detemined by flow cytometry. Results The IC₅₀ of the Tca83 cells was 5 mg.L^-1 after treated with DDP；the MTT results showed that the cell survival rate in  DDP group was significantly lower than those in  control group and 3-MA + DDP group (P<0.05),and  higher than that in  DDP +3- MA group (P<0.0
5)；the immunofluorescence results showed that the average fluorescence intensity in 3-MA group was significantly lower than those in  the other four groups (P<0.05 );the flow cytometry results showed that the  apoptotic rate  in DDP group was significantly lower than that in  3-MA + DDP group(P<0.05),and higher than that in DDP +3-MA group (P<0.05).Conclusion The autophagy at different levels has different roles in oral squamous cell carcinoma.The inhibition of basic level autophagy of  the Tca83 cells can enhance the cytotoxicity  of DDP. It indicates that the autophagy inhibitor has significant potential to be a novel chemotherapeutic enhancer for oral squamous cell carcinoma therapy.

Key words:  autophagy；apoptosis；oral squamous , carcinoma cell；cisplatin；3-methyladenine