Overexpression of Ubiquilin4 is associated with poor prognosis in patients with cervical cancer

BACKGROUND: Ubiquilins (UBQLNs) are important factors for cell proteostasis maintenance. UBQLNs are involved in the modulation of the cell cycle, as well as in apoptosis, membrane receptors regulation, DNA repair, epithelial-mesenchymal transition, and miRNA activities. They also affect the selection of double-strand break repair pathways. Abnormal UBQLNs expression can lead to many diseases, including cancer. Studies have found that the expression of Ubiquilin4 (UBQLN4) is associated with the development of several tumor types. However, the association between UBQLN4 and cervical cancer has not been examined yet. AIM: To investigate the expression of UBQLN4 in cervical cancer and to evaluate its correlation with disease prognosis. METHODS: Immunohistochemistry was performed to examine the expression of UBQLN4 in 117 cervical cancer tissues and 32 matching pericervical tissues. Paired t-test (two-tailed) was used to compare the differences between groups. We collected patients’ clinical characteristics, including age, histological grade, pathologic type, lymph node metastasis, and FIGO stage (2018) and compared them by chi-square test. All patients were followed for 5.5 to 6.8 years. Kaplan-Meier method and log-rank test were used to compare the differences in the overall survival (OS) and progression-free survival (PFS) among the different groups. RESULTS: Overexpression of UBQLN4 was observed in 70.9% (83/117) of all cervical cancer tissues and in 15.6% (5/32) of the paired parauterine tissues. The expression of UBQLN4 was associated with lymph node metastasis, poor differentiation, and advanced stage, but the difference was not significant. Kaplan-Meier and log-rank test results suggested the high expression of UBQLN4 was associated with short OS and PFS. Regardless of UBQLN4 expression, the patient age and FIGO stage were also associated with disease prognosis. The statistically significant variables obtained from univariate the Kaplan-Meier analysis were subjected to Cox multivariate survival regression analysis, which showed that, in addition to the FIGO stage and age, UBQLN4 was also an independent prognostic marker for OS and PFS (P = 0.011 and P = 0.024, respectively). CONCLUSION: The overexpression of UBQLN4 was associated with poor prognosis in cervical cancer. Our study proposed a novel prognostic factor and improved the existing understanding of the pathogenesis of cervical cancer.