Inhibitory Effect of UHRF1 on Invasion and Migration of Colorectal Cancer Cells via WNT/MMP9 Signaling Pathway

Objective To explore the relationship of UHRF1 with the clinicopathological characteristics of colorectal cancer (CRC) patients, as well as the effects of lentivirus transfection overexpression and knockdown of UHRF1 on the proliferation, invasion, and migration of CRC cells and the possible signaling pathways.

Methods The expression of UHRF1 mRNA and protein in CRC tissues and adjacent tissues was detected by immunohistochemical staining and RT-PCR. The effects of the constructed UHRF1 overexpression- and knockdown-group cells on the expression of UHRF1, related molecules in the WNT signaling pathway, and MMPR9 were examined by Western blot and RT-PCR. EDU and Transwell assays were used to detect changes in the proliferation, migration, and invasion of CRC cells.

Results (1) In the TCGA database and clinical data, the mRNA and protein expression levels of UHRF1 in CRC cancer tissues were significantly higher than those in adjacent normal tissues. UHRF1 expression was closely correlated with TNM stage, N stage, and M stage. Patients with low UHRF1 expression in TCGA had better 5-year OS and disease-specific survival. The area under the ROC curve of UHRF1 for predicting 1-, 3-, and 5-year OS were 0.634, 0.652, and 0.771, respectively. The 3-year OS in the clinical data also showed the same survival benefit. UHRF1 overexpression was a poor prognostic factor for CRC patients. (2) After UHRF1 overexpression, the expression of WNT3a, GSK3β, and MMP9 in SW480 cells significantly increased, whereas the expression of p-β-catenin decreased (P < 0.05). After UHRF1 knockdown, the expression of WNT3a, GSK3β, and MMP9 in HCT116 cells decreased, whereas the expression of p-β-catenin increased (P < 0.05). The "rescue" experiment with IWP-2 and HLY78 can produce consistent results. (3) Compared with the control group, the cell proliferation, migration, and invasion abilities of the UHRF1 overexpression group were enhanced. After IWP-2 treatment, the cell proliferation, migration, and invasion abilities were inhibited. Knockdown experiment exhibited the reverse results to overexpression experiment.

Conclusion UHRF1 may play an important role in the occurrence and development of CRC. UHRF1 overexpression may be a poor prognostic factor for CRC patients. UHRF1 may affect the proliferation, migration, and invasion of CRC cells through the WNT/MMP9 signaling pathway.