ABSTRACT
Endometrial carcinoma is one of the most common malignancies in the female reproductive system. Interleukin-37 (IL-37) is a newly discovered anti-inflammatory factor belonging to the IL-1 family. IL-37 has five different isoforms, and IL-37b is the most biologically functional subtype. In recent years, the protective roles of IL-37 in different cancers, including lung and liver cancers, have been successively reported. IL-37 also plays an important role in some gynecological diseases such as endometriosis, adenomyosis, and cervical cancer. However, the role and mechanism of IL-37b, especially the mature form of IL-37b, in endometrial carcinoma have not been elucidated. The present study demonstrated that IL-37 protein was downregulated in endometrial carcinoma cells compared with the control endometrium. IL-37b did not affect the proliferation and colony-forming ability of endometrial cancer cells. A mature form of IL-37b (IL-37bΔ1-45) effectively suppressed the migration and invasion of endometrial cancer cells by decreasing the expression of matrix metalloproteinase 2 (MMP2) via Rac1/NF-κB signal pathway. However, it did not affect epithelial-mesenchymal transition (EMT) or filamentous actin (F-actin) depolymerization of endometrial cancer cells. IL-37bΔ1-45 attenuated tumor metastasis in a peritoneal metastatic xenograft model of endometrial cancer. To sum up, these results suggested IL-37b could be involved in the pathogenesis of endometrial carcinoma and provide a novel target for the diagnosis and treatment of endometrial carcinoma.
Subject(s)
Carcinoma, Endometrioid/drug therapy , Endometrial Neoplasms/drug therapy , Interleukin-1/therapeutic use , Signal Transduction/drug effects , Actins/metabolism , Adult , Aged , Animals , Carcinoma, Endometrioid/metabolism , Cell Line, Tumor , Endometrial Neoplasms/metabolism , Epithelial-Mesenchymal Transition/drug effects , Estrogens , Female , Humans , Interleukin-1/metabolism , Interleukin-1/pharmacology , Matrix Metalloproteinase 2/metabolism , Mice, Inbred BALB C , Mice, Nude , Middle Aged , NF-kappa B/metabolism , Progesterone , Xenograft Model Antitumor Assays , rac1 GTP-Binding Protein/metabolismABSTRACT
Programmed cell death 4 (PDCD4) is regarded as an important tumor suppressor that is lowly expressed or deleted in numerous human types of cancer, including ovarian and endometrial cancer. Tripartite motifcontaining 27 (TRIM27) is closely related to the occurrence and development of tumors and is highly expressed in numerous types of cancer such as ovarian and endometrial cancer. PDCD4 can be degraded through ubiquitination, while TRIM27 has the E3 ubiquitin ligase activity. However, whether TRIM27 may regulate the expression of PDCD4 by ubiquitination effect remains unclear. In the present study, the expression of PDCD4 and TRIM27 in different ovarian and endometrial cancer cell lines was detected by reverse transcriptionquantitative PCR (RTqPCR), western blotting and immunocytochemistry. The impact of TRIM27 overexpression and knockdown on PDCD4 expression and the effective mechanism of TRIM27 regulating PDCD4 expression were also investigated in vitro by RTqPCR, western blotting, coimmunoprecipitation assay, Transwell migration and Matrigel invasion assays. The results showed that the expression of TRIM27 and PDCD4 had a negative association at the protein level, and the distribution of TRIM27 and PDCD4 proteins had a phenomenon of colocalization in different ovarian and endometrial cancer cell lines. TRIM27 promoted the degradation of PDCD4 through the ubiquitinproteasome pathway. To sum up, TRIM27 could increase the migration and invasion of ovarian and endometrial cancer cells by promoting the ubiquitination and degradation of PDCD4. The present findings may provide a new target for the treatment of ovarian and endometrial cancer.