Mechanism Of EGFR-PKM2-STAT3 Signal Transduction Pathway In The Development Of Cervical Cancer

Objective:To analysis of EGFR and PKM2,STAT3 in cervical cancer tissue adjacent to carcinoma tissues and the expression level difference and its clinical pathological parameters and cancer related indicators of the relationship,then by cytology in vitro experiments,further validation of the EGFR gene expression and silence about cervical cancer SiHa biological behavior,such as cell growth,invasion,and apoptosis,and to explore the effect and its related regulation gene PKM2,whether there is internal relationship between the expression of STAT3 and reveal the molecular mechanism of EGFR on cervical cancer SiHa cells act.Methods :(1)The expression of EGFR,PKM2 and STAT3 in cervical cancer tissues and paracancerous tissues were detected by immunohistochemical method at the tissue level,and the relationship between the above factors and the occurrence and outcome of cervical cancer was analyzed by combining the clinical malignant phenotype parameters of patients with cervical cancer.(2)The SIHA cervical cancer cells were transfected at the cell experimental level,and the effects of EGFR on the growth,invasion and apoptosis of SIHA cervical cancer cells were detected by overexpression and silencing of EGFR receptors.RT-PCR and Western blot were used to investigate the effects of EGFR overexpression and silencing on STAT3 and PKM2 related regulatory genes in cervical cancer cells from gene and protein levels,respectively.Results:(1)the normal tissue adjacent to carcinoma of EGFR expression positive rate is16.4%(18/73),however in cervical cancer tissues expression rate is 87.6%(64/73),and cervical cancer tissue expression of EGFR and significantly increased compared with the normal tissue adjacent to carcinoma,tumor infiltration depth > 1/2 of the cervical wall thickness EGFR protein expression positive rate is higher in patients with cervical cancer,and there are statistically significant;However,there was no significant difference in the positive rate of EGFR protein expression among patients with age,histological differentiation and clinical stage(P> 0.05).The immunohistochemical results of PKM2 showed that the positive expression rate of PKM2 in normal paracancerous tissues was15.06%(11/73).The positive rate of PKM2 expression in cervical cancer tissues was 89%(65/73),and there was no statistical difference in PKM2 expression among patients with uterine tumor invasion depth,age,histological differentiation and clinical stage.The expression rate of STAT3 in adjacent tissues of cervical cancer was 24.6%(18/73),while the positive rate of STAT3 was 80.8%(59/73)in cancer tissues.There was no significant statistical correlation between the expression of STAT3 in uterine malignant tissues and the stage,age and degree of differentiation of patients(P > 0.05).(2)Si HA cervical cancer cells with overexpression of EGFR were transfected with lentivirus,and the proliferation,invasion and migration of the cells were significantly promoted,while the functions of the above cells were significantly decreased after knockout of EGFR,with biological statistical significance(P<0.05).Flow cytometry analysis of cell cycle results showed that in the EGFR overexpression group,the control group and the no-load group,the number of DNA synthesis phase cells in the EGFR overexpression group was significantly increased compared with the other two groups,while the number of G1 phase cells was significantly decreased compared with the other two groups(P<0.05).Compared with the other two groups,the number of cells in the EGFR knockout group was significantly higher in the prophase than the other two groups,and the number of cells in the G2 phase and S phase was significantly lower than the other two groups,indicating that the growth of SIHA cells in the EGFR overexpression group was out of control and division was active.RT-PCR assay,WB assay and immunofluorescence assay showed that after transfection,the expression levels of PKM2 and STAT3 in the EGFR overexpression group were significantly higher than those in the control group and no-load group,while the expression levels of the above two factors in the knockout group were significantly decreased,indicating that there was a positive correlation between EGFR and PKM2 and STAT3 expression.Conclusion: The expressions of EGFR,PKM2 and STAT3 in cervical cancer tissues were higher than those in adjacent normal tissues.The increase of EGFR expression significantly promoted the proliferation,invasion,metastasis and other malignant biological behaviors of cervical cancer cells,and increased the resistance to cervical cancer cell apoptosis.The expression of EGFR in cervical cancer is positively correlated with the expression of PKM2 and STAT3,suggesting that EGFR may act on cervical cancer SiHa cells through the PKM2-STAT3 pathway.