The Expression Of CBX2 Protein In Oral Squamous Cell Carcinoma Tissues And Its Effects On The Proliferation And Migration Of CAL-27 Cells

Objective:To study the relationship between the expression of CBX2 protein in oral cancer(Oral Squamous Cell Carcinoma,OSCC)and the patient’s clinicopathological indicators(gender,age,lesion location,cancer differentiation,lymph node metastasis,and survival)And the effect of CBX2 gene silencing on the proliferation and migration of oral cancer CAL-27 cells provides a research basis for judging the prognosis of oral cancer patients and their targeted therapy.Methods:1.Analyze the expression of CBX2 gene in head and neck squamous cell carcinoma and normal tissues through the GEPIA database,the Gene Expression Profiling Interactive Analysis(Gene Expression Profiling Interactive Analysis,http://gepia.cancer-pku.cn).2.Through immunohistochemical experiments,detect the expression of CBX2 protein in oral cancer tissues,and analyze the relationship between CBX2 protein and the patient’s clinicopathological indicators(gender,age,lesion location,cancer differentiation,lymph node metastasis and survival).Experimental group: Selected specimens from 126 patients diagnosed with oral squamous cell carcinoma who were admitted to the Department of Oral and Maxillofacial Surgery of the Stomatological Hospital of Jilin University from 2011 to 2015(including 81 male patients and 45 female patients;those younger than 60 years old)77 cases,49 cases were 60 years and older;the affected parts were tongue(39 cases),gums(25 cases),floor of mouth(22cases),lips(11 cases),cheeks(10 cases),others location(19 cases);from the perspective of the degree of differentiation,38 cases were well-differentiated,71 cases were moderately differentiated,and 17 cases were poorly differentiated;64 cases had lymph node metastasis and 62 cases had no metastasis;there were 65 patients survived and 61 patients died.)Clinical data and postoperative follow-up data are complete.Control group: 20 paracancerous tissues(The frozen pathological result during the operation is the border without tumor cells).3.Effect of CBX2 gene silencing on the proliferation and migration of oral cancer CAL-27 cells(1)Constructed and screened CBX2 si RNA,Lipo2000 transiently transfected CAL-27 cells by real-time PCR assay the cells of CBX2 m RNA relative expression levels.(2)The expression of the selected CBX2 si RNA at the protein level was verified by western blot experiment.(3)The effect of CBX2 gene silencing on the proliferation of CAL-27 cells was detected by MTS cell proliferation test.(4)The effect of CBX2 gene silencing on the migration of CAL-27 cells was observed by cell scratch test.Results:1.According to the analysis of the GEPIA database,the expression of CBX2 gene in head and neck squamous cell carcinoma was higher than that in normal tissues,and the difference was significant(P<0.05).And CBX2 has a positive correlation with Ki-67,a nuclear antigen related to cell proliferation.2.Immunohistochemistry results showed that CBX2 protein was positively expressed in the nucleus and/or cytoplasm in oral cancer tissues,and its expression intensity increased with the decrease of cancer differentiation;and the expression intensity of CBX2 in patients with lymph node metastasis was higher than that in nonmetastatic patients,and was positively correlated with the patient’s lymph node metastasis;the CBX2 expression intensity of dead patients was higher than that of survivors,and was negatively correlated with patients’ survival(P<0.05).There was no correlation with the patient’s gender,age,and location of disease(P>0.05).But not or lowly expressed in normal adjacent tissues.3.CBX2 gene silencing experiment results:(1)Three CBX2 si RNAs were designed and synthesized.After the cells were transfected,the RT-q PCR results showed that the relative expression of CBX2 m RNA in the CBX2 si RNA-1 group was the lowest,which was significantly lower than that of the NC-si RNA group and the blank control group,and the difference was significant(P<0.0001).(2)Western blot experiments showed that the CBX2 protein expression in CAL-27 cells was significantly lower than the NC-si RNA group and the blank control group after the interference of CBX2 si RNA-1,and the difference was significant(P<0.0001).(3)The results of cell proliferation experiments showed that with the extension of the culture time,the cell proliferation rate of the CBX2 si RNA-1 group was significantly lower than that of the NC-si RNA group and the blank control group,and the difference was significant(P<0.05).(4)The results of the cell scratch experiment showed that 24 hours after the scratch treatment,the cells in the CBX2 si RNA-1 group had the shortest migration distance and the lowest migration healing rate,while the control group could restore more than 50%of the healing,compared with the NC-si RNA group and the blank control the difference was significant(P<0.0001).Conclusion:1.CBX2 protein is positively and highly expressed in oral cancer tissues;the expression intensity increases with the decrease of cancer differentiation,and is positively correlated with the patient’s lymph node metastasis;it is negatively correlated with the patient’s survival.It is suggested that the high expression of CBX2 protein is related to the malignant degree of oral cancer,and may indicate that patients with oral cancer have a tendency to lymph node metastasis and a poor prognosis.2.CBX2 gene silencing can effectively inhibit the proliferation and migration of oral cancer CAL-27 cells.It suggests that the CBX2 gene may be a potential target for the treatment of oral cancer patients.