Protein Tyrosine Kinase 7 Regulates EGFR-PI3K-AKT Signaling Pathway In Triple-negative Breast Cancer

Objective At present,the new incidence of breast cancer has leapt to the first place among female malignant tumors,which seriously threatens women's physical and mental health.This is a malignant tumor arises from the combined action of multiple genes and environmental factors.Its occurrence,development and prognosis are often related to the individual's physiological states.Factors such as living environments and genetic differences are also closely related.In the past 10 years,the incidence of breast cancer in some European and American countries has peaked and then declined,while the incidence in some Asian countries has shown a significant upward trend.In recent years,with the development of society and economy,and changes in both lifestyles and the ecological environments,the incidence of women's breast cancer in my country has presented a rising trend year by year.It can also be attributed to the large population base,the number of cases and deaths of breast cancer each year is high because the number of people in my country occupies the first place in the world.Receptor protein tyrosine kinase(RTK)is the largest transmembrane receptor and it plays an important role in cell signal transduction.RTK matters much in the process of cell growth,proliferation,differentiation,migration,and apoptosis,and it is closely linked with the occurrence and development of tumors.Among them,protein tyrosine kinase 7(PTK7)is a receptor protein tyrosine kinase(RTK)that lacks catalytic activity.Many studies have found that PTK7 is involved in many human malignant tumors and highly expressed in the people having cancer.The EGFR-PI3K-AKT pathway regulates cell growth,proliferation,differentiation,adhesion and migration and other activities,which is also closely related to the occurrence and development of tumors.This study analyzed the regulatory relationship between PTK7 and the EGFR-PI3K-AKT pathway,and clarified their roles in the occurrence and development of breast cancer,as well as provided new ideas for the prevention and treatment of breast cancer.Methods 1.This study first analyzed the pathways related to PTK7 functional changes in invasive breast cancer by KEGG.2.In triple-negative breast cancer,cell lines(MDA-MB-231,MDA-MB-468)by constructing PTK7 lentiviral small interfering RNA and PCDNA-PTK7-VSV plasmid overexpression vector,establish PTK7 knockdown and overexpression respectively.The triple-negative breast cancer cell line model was verified by Western Blot.3.Use DAVID tool to do GO analysis of PTK7,use GEPIA to do related gene analysis of PTK7 and cell migration-related genes,and further verify with RT-PCR.At the same time,we perform cytoskeleton staining to observe the morphological changes of the cytoskeleton.Results 1.The results of KEGG analysis found that PTK7 is involved in the regulation of the EGFR-PI3K-AKT signaling pathway and the regulation of the actin cytoskeleton in invasive breast cancer.2.In the typing of invasive breast cancer,the expression of PTK7 in triple-negative breast cancer cell lines is significantly higher.The experiment successfully established a triple-negative breast cancer cell line model with knockdown and overexpression of PTK7 respectively.It was found that after knocking down PTK7,the EGFR-PI3K-AKT pathway was significantly inhibited;when the plasmid was transfected to overexpress PTK7,the EGFR-PI3K-AKT pathway was significantly upregulated.3.GO analysis found that PTK7 is significantly related to extracellular matrix,cell adhesion and cell migration.The GEPIA correlation analysis tool found gene clusters co-expressed by PTK7 and cell migration in breast cancer.It was found that SDC1?MMP11?FN1 and COL1A1 were significantly related to PTK7.QPCR results showed that expression of SDC1? MMP11? FN1 and COL1A1 is significantly correlated with the expression of PTK7.In the cytoskeleton staining experiment,it was found that in triple-negative breast cancer cells,after knocking down PTK7,the axiality of the microfilaments in the cytoskeleton of triple-negative breast cancer decreased significantly,and the cell polarity decreased significantly,too.Conclusion 1.In triple-negative breast cancer,PTK7 affects the activation of EGFR-PI3K-AKT signaling pathway.2.In triple-negative breast cancer,PTK7 is related to cell adhesion and migration.3.In triple-negative breast cancer,PTK7 affects cell polarity and changes the cytoskeleton morphology.