Abstract
Ovarian cancer is the leading malignancy of the female reproductive system and is associated with inconspicuous early invasion and metastasis. We have previously reported that the oncogene OTUB1 plays a crucial role in ovarian cancer progression, but the role of its isoform, the non-coding RNA OTUB1-isoform2, in ovarian cancer is still elusive. Here, we reported that OTUB1-isoform2 expression in ovarian cancer tissues was significantly higher than that in the paired paratumorous tissues (P < .01). The patients with high expression of OTUB1-isoform2 had larger tumours than those with low expression (P < .05). The high expression of OTUB1-isoform2 was correlated with the involvement of bilateral ovaries (P < .05), lymph node metastasis (P < .05), vascular invasion (P < .05), greater omentum involvement (P < .01), fallopian tube involvement (P < .05), advanced FIGO stages (P < .01) and recurrence (P < .01). Moreover, OTUB1-isoform2 served as an independent negative prognostic predictor for disease-free survival (DFS) and disease-specific survival (DSS). Overexpression of OTUB1-isoform2 in the ovarian cancer cells stimulated cell proliferation, migration and invasion both in vitro and in vivo. In summary, our study suggested that OTUB1-isoform2 is a novel prognostic biomarker with independent oncogenic functions for ovarian cancer.