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Abstract Deoxyhypusine synthase (DHPS) is an enzyme encoded by the DHPS gene, with high expression in various cancers, including ovarian cancer (OC). DHPS regulates the translation initiation factor EIF5A, and EIF5A2 knockout inhibits OC tumor growth and metastasis by blocking the epithelial-to-mesenchymal transition (EMT) and the TGFβ pathway. In this study, we show that DHPS is amplified in OC patients, and its elevated expression correlates with poor survival. Using lentiviral CRISPR/Cas9 vectors for DHPS knockout, we observed EMT inhibition in SKOV3 and OVCAR8 cells through suppressed hypusination and reduced EIF5A2 expression. Inhibition of DHPS activity with GC7 similarly blocked hypusination and EMT. Disrupting DHPS expression, either genetically or pharmacologically, inhibited primary tumor growth and metastasis in OC mouse models. These findings suggest that targeting DHPS and inhibiting hypusination could be promising strategies for OC treatment.

Abstract Background We previously reported that miR-203 functions as a tumor suppressor in ovarian cancer cells by directly targeting transcription factor Snai2 and inhibiting epithelial to mesenchymal transition (EMT), whereas BIRC5/survivin promotes EMT. In this study, we tested our hypothesis that miR-203 inhibits ovarian tumor metastasis by suppressing EMT through targeting BIRC5, using an orthotopic ovarian cancer mouse model. Methods We overexpressed miR-203 in ovarian cancer SKOV3 and OVCAR3 cells using a lentiviral vector and examined cell migration and invasion using transwell plates. The small molecule inhibitor, YM155, was used to inhibit survivin expression. miR-203-expressing and control SKOV3 cells were intrabursally injected into immunocompromised NSG female mice. Primary tumors in ovaries and metastatic tumors were collected to determine the expression of survivin and EMT markers using Western blot and immunostaining. Results Overexpression of miR-203 inhibits EMT by targeting BIRC5 in ovarian cancer SKOV3 and OVCAR3 cells. miR-203 expression enhances the ability of the survivin inhibitor YM155 to reduce tumor cell migration and invasion in vitro. We further showed that miR-203 expression attenuated the TGFβ pathway in both SKOV3 and OVCAR3 cells. miR-203 expression also inhibited primary tumor growth in ovaries and metastatic tumors in multiple peritoneal organs including liver and spleen. Conclusion miR-203 inhibits ovarian tumor metastasis by targeting BIRC5/survivin and attenuating the TGFβ pathway.

Deoxyhypusine synthase (DHPS) is an enzyme encoded by the DHPS gene, with high expression in various cancers, including ovarian cancer (OC). DHPS regulates the translation initiation factor EIF5A, and EIF5A2 knockout inhibits OC tumor growth and metastasis by blocking the epithelial-to-mesenchymal transition (EMT) and the TGFβ pathway. In this study, we show that DHPS is amplified in OC patients, and its elevated expression correlates with poor survival. Using lentiviral CRISPR/Cas9 vectors for DHPS knockout, we observed EMT inhibition in SKOV3 and OVCAR8 cells through suppressed hypusination and reduced EIF5A2 expression. Inhibition of DHPS activity with GC7 similarly blocked hypusination and EMT. Disrupting DHPS expression, either genetically or pharmacologically, inhibited primary tumor growth and metastasis in OC mouse models. These findings suggest that targeting DHPS and inhibiting hypusination could be promising strategies for OC treatment. [ABSTRACT FROM AUTHOR]

Background: We previously reported that miR-203 functions as a tumor suppressor in ovarian cancer cells by directly targeting transcription factor Snai2 and inhibiting epithelial to mesenchymal transition (EMT), whereas BIRC5/survivin promotes EMT. In this study, we tested our hypothesis that miR-203 inhibits ovarian tumor metastasis by suppressing EMT through targeting BIRC5, using an orthotopic ovarian cancer mouse model. Methods: We overexpressed miR-203 in ovarian cancer SKOV3 and OVCAR3 cells using a lentiviral vector and examined cell migration and invasion using transwell plates. The small molecule inhibitor, YM155, was used to inhibit survivin expression. miR-203-expressing and control SKOV3 cells were intrabursally injected into immunocompromised NSG female mice. Primary tumors in ovaries and metastatic tumors were collected to determine the expression of survivin and EMT markers using Western blot and immunostaining. Results: Overexpression of miR-203 inhibits EMT by targeting BIRC5 in ovarian cancer SKOV3 and OVCAR3 cells. miR-203 expression enhances the ability of the survivin inhibitor YM155 to reduce tumor cell migration and invasion in vitro. We further showed that miR-203 expression attenuated the TGFβ pathway in both SKOV3 and OVCAR3 cells. miR-203 expression also inhibited primary tumor growth in ovaries and metastatic tumors in multiple peritoneal organs including liver and spleen. Conclusion: miR-203 inhibits ovarian tumor metastasis by targeting BIRC5/survivin and attenuating the TGFβ pathway. [ABSTRACT FROM AUTHOR]