RESUMO
OBJECTIVES@#To investigate the relationship between the fatty acid-binding protein 4 (FABP4) and colorectal cancer (CRC).@*METHODS@#Using an enzyme-linked immunosorbent assay (ELISA), we measured the expression of FABP4 in plasma of 50 patients who underwent surgery for CRC from October 2017 to May 2018 and 50 healthy controls. The content of the visceral fat area (VFA) as seen with abdominal computed tomography (CT) scanning was measured by ImageJ software. The expression levels of FABP4, E-cadherin, and Snail proteins in CRC and adjacent tissues were determined by immunohistochemistry.@*RESULTS@#The mean concentration of plasma FABP4 of CRC patients was higher than that of the control group (22.46 vs. 9.82 ng/mL; @*CONCLUSIONS@#High LPA and VFA were risk factors for increased plasma FABP4 in CRC patients. FABP4 protein was highly expressed in CRC tissues and associated with TNM stage, differentiation, and lymph node metastasis of CRC. The level of FABP4 in CRC tissue was correlated with E-cadherin and Snail expression, suggesting that FABP4 may promote CRC progression related to epithelial-mesenchymal transition (EMT).
RESUMO
@#Objective: To investigate the potential effects of miR-455-3p on proliferation, invasion and epithelial-mesenchymal transition (EMT) process of ovarian cancer cells, and explore its molecular mechanism. Methods: The IOSE80, SKOV-3 and A2780 cells were transfected with miR-455-3p mimics and negative controls (NC) by using LipofectamineTM 2000. Quantitative polymerase chain reaction (qPCR) assay was performed to detect the mRNA expressions of miR-455-3p and fatty acid-binding protein 4 (FABP4) in IOSE80, SKOV-3 and A2780 cells. The expression levels of FABP4 and EMT-associated proteins were detected by Wb. CCK-8 assay was applied to measure cell proliferation. Cell migration was analyzed by using Transwell assay. Bioinformatics analysis was used to predict the potential target of miR-455-3p, and the targeting effect of miR-455-3p on FABP4 was verified by the dual-luciferase reporter assay system. Results: The expression of miR-455-3p was declined (all P<0.05), while the expression of FABP4 was elevated (all P< 0.05) in ovarian cancer cells (SKOV-3 and A2780) in comparison with normal ovarian IOSE80 cells. Additionally, over-expression of miR-455-3p obviously inhibited cell proliferation and migration capacity of SKOV-3 cells (all P<0.05). Furthermore, over-expression of miR-455-3p impeded EMT progress by up-regulating E-cadherin expression and down-regulating N-cadherin and vimentin expression (all P<0.05). Importantly, the dual-luciferase reporter system, qPCR and Wb validated that FABP4 was a specific target gene of miR-455-3p, and miR-455-3p showed specific binding with FABP4 3’-UTR and negatively regulated the expression of FABP4 at both mRNA and protein levels. Mechanistically, over-expression of FABP4 apparently reversed the inhibitory effects of miR-455-3p on cell proliferation and migration of SKOV-3 cells (all P<0.05). Conclusion: miR-455-3p, acting as a tumor suppressor protein, can inhibit ovarian cancer cell proliferation, migration and EMT process by targeting FABP4, suggesting that miR-455-3p may be a new potential therapeutic target for ovarian cancer treatment.