Background: Ovarian carcinoma represents one of the most insidious and aggressive cancers. Ovarian carcinoma is the most lethal gynecological malignancy. To discover new relevant biomarkers to increase specificity and sensitivity for early diagnosis and prognosis of ovarian cancer is important and urgently needed. FOXO3a possesses a large series function including cellular proliferation, transformation, differentiation, and longevity. Jab1 is also known as subunit 5 (CSN5) of the COP9 signalosome (CSN), a multifunctional protein complex involved in modulating signal transduction, gene transcription, and protein stability.
Objective: To investigate the importance of FOXO3a and Jab1 in ovarian cancer.
Method: Immunohistochemical analysis was performed on formalin-fixed paraffin sections of 46 specimens. Statistical analysis was conducted using the Stat View 5.0 software package.
Result: We found that Foxo3a expression correlates significantly with FIGO disease stage (p < 0.05) and lymph node involvement. Jab1 expression correlates significantly with disease stage and lymph node involvement (p < 0.05). A multivariate Cox proportional hazard model showed that Foxo3a and Jab1 were the strongest independent predictors of survival (p < 0.05), the second predictor being FIGO disease stage and lymph node involvement.
Conclusion: Understanding the precise role of Jab1 and Foxo3a in ovarian cancer progression will not only increase our knowledge of the biology of ovarian cancer but may also enable development of an novel therapeutic strategy via suppression of Jab1.
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