1. Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, No. 36, Sanhao Street, Heping District, Shenyang, 110004, China.
2. Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning, China.
Background: Ovarian cancer is one of the most common malignant tumors in female reproductive system. The expression of CD147 and human epididymis protein 4 (HE4) are both upregulated and associated with malignant progression in ovarian cancer. However, the important role of interaction between CD147 and HE4 in the invasion and metastasis of ovarian cancer remains unclear.
Methods: The co-expression and co-localization of CD147 and HE4 in cells and tissues of ovarian cancer were detected by co-immunoprecipitation, immunohistochemistry and immunocytochemistry, double-labeling immunofluorescence method. The interaction between CD147 and annexin A2 (ANXA2) was also investigated. Furthermore, we detect the regulatory relationship between CD147 and HE4 by Western blot. Transwell assay and scratch test were conducted to explore the effect of CD147-HE4 interaction on migration and invasion of ovarian cancer.
Results: The protein CD147 and HE4 were co-immunoprecipitated and co-located in the cytoplasm and membrane of ovarian cancer tissues and cells. Both of two proteins were highly expressed and positively associated with advanced FIGO stages, poor differentiation degree and poor prognosis of ovarian cancer, and HE4 was confirmed as an independent risk factor for CD147 in ovarian cancer tissues. What's more, AXNA2 was also identified as a CD147 interacting protein in ovarian cancer. It is further confirmed that interaction between CD147 and HE4 can affect the invasion and metastasis of ovarian cancer.
Conclusion: This study demonstrated that HE4 and ANXA2 were both CD147 interacting proteins, the expression of CD147 and HE4 can affect each other, and HE4 could promote the invasion and metastasis of ovarian cancer by regulating the expression of CD147, which may provide novel thought for early diagnosis and therapeutic target of ovarian cancer.
Keywords: CD147, human epididymis protein 4, ovarian cancer, invasion and metastasis