Mechanism Of Chloroquine In Promoting Sensitivity Of Chemotherapeutics In Oral Squamous Cell Carcinoma CAL-27Cell Line To Cisplatin

Objective: To study the role and mechanisms of autophagy in the chemotherapy oforal squamous cell carcinoma, hoping it can provide theoretical evidence to improvethe chemotherapeutic activity of oral squamous cell carcinoma patients.Methods: The cell survival rate changes induced by DDP and CQ in CAL-27cellswhich was assayed by tetrazolium bromide (MTT) colorimety; the LC3-Ⅱexpression level was detected by laser scanning confocal microscope; the apoptoticrate was detemined by flow cytometry.Results:1. MTT results showed that compared with control group,the cell survivalrate reducing with the extend time of DDP and CQ treatment; the optimalconcentration of the CAL-27cells was5mg·L-1after treated with CQ, IC50of theCAL-27cells was5mg·L-1after treated with DDP; MTT results showed that the cellsurvival rate of CQ+DDP group was significantly lower than the control group, CQgroup and DDP group (P <0.05)；2. With the action of CQ and DDP to CAL-27cellsin48hours,Immunofluorescence results showed that the average fluorescenceintensity of DDP group was significantly higher than the other three groups (P<0.05), CQ group was significantly lower than the other three groups (P <0.05);3.With the action of CQ and DDP to CAL-27cells in48hours, Flow cytometry resultsshowed that the cell apoptosis rate of DDP group and CQ+DDP group wassignificantly higher than control group and CQ group, the cell apoptosis rate ofCQ+DDP group was significantly higher than DDP group (P <0.05).4. With the action of CQ and DDP to CAL-27cells in48hours, cells in G1phase ofDDP group and CQ+DDP group were increased, indicating G1phase blockage, thecells in G1phase of CQ+DDP group was significantly more than DDP group (P<0.05).Conclusion: The inhibition of autophagy can enhanced the sensitivity of chemoth-erapeutic of DDP in the CAL-27cells. The basic level of autophagy is an importantmechanism for chemotherapy resistance of oral squamous cell carcinoma. It indicatesthat the autophagy inhibitor has significant potential to be a novel chemotherapeuticenhancer for oral squamous cell carcinoma therapy.