Background: The regulator of cullins-1 (ROC1) is an essential subunit in the cullin-RING ligase (CRL) protein complex and has been shown to be critical in bladder cancer cell survival and progression. This study aimed to explore the molecular mechanism of ROC1 action in the malignant progression of bladder cancer.Methods: This study utilized ex vivo, in vitro, and in vivo nude mouse experiments to assess the underlying mechanisms of ROC1 in bladder cancer cells. The expression of the components of the sonic hedgehog (SHH) pathway was determined by western blot analysis. ROC1 expression in human tumors was evaluated by immunohistochemistry.Results: ROC1 overexpression promoted the growth of bladder cancer cells, whereas knockdown of ROC1 expression had the opposite effect in bladder cancer cells. Mechanistically, ROC1 was able to target suppressor of fused homolog (SUFU) for ubiquitin-dependent degradation, allowing Gli2 release from the SUFU complex to activate the SHH pathway. Furthermore, knockdown of SUFU expression partially rescued the ROC1 knockdown-suppressed SHH activity as well as cancer cell growth inhibition. In ex vivo experiments, tissue microarray analysis of human bladder cancer specimens revealed a positive association of ROC1 expression with the SHH pathway activity. Conclusion: This study demonstrated that dysregulation of the ROC1–SUFU–GLI2 axis plays an important role in bladder cancer progression and that targeting ROC1 expression is warranted in further investigations as a novel strategy for the future control of bladder cancer.

Background: The regulator of cullins-1 (ROC1) is an essential subunit in the Cullin-RING ligase (CRL) protein complex and was shown to be critical in bladder cancer cell survival and malignant progression. This study aimed to explore the regulatory mechanism of ROC1 in bladder cancer malignant progression. Methods: This study explored the underlying mechanisms using both in vitro and in vivo experiments. The expression of the components of Sonic Hedgehog (SHH) pathway was determined by western blotting analysis. ROC1 expression in human tumours was evaluated by immunohistochemical analysis. Results: The data showed that ROC1 overexpression promoted growth of bladder cancer cells, whereas knockdown of ROC1 expression had an opposite effect in bladder cancer cells. Mechanistically, ROC1 was able to target SUFU for ubiquitin-dependent degradation, allowing the Gli2 release from the SUFU complex to activate SHH pathway. Furthermore, knockdown of SUFU expression partially rescue the ROC1 knockdown-suppressed SHH activity as well as cancer cell growth inhibition. At ex vivo, tissue microarray analysis of human bladder cancer specimens revealed an positive association of ROC1 expression with the SHH pathway activity. Conclusion: The current study demonstrated the dysregulation of ROC1-SUFU-GLI2 axis played an important role in bladder cancer progression and targeting of ROC1 expression is warranted further investigation as a novel strategy for future control of bladder cancer.

Background: The regulator of cullins-1 (ROC1) is an essential subunit in the cullin-RING ligase (CRL) protein complex and has been shown to be critical in bladder cancer cell survival and progression. This study aimed to explore the molecular mechanism of ROC1 action in the malignant progression of bladder cancer.Methods: This study utilized ex vivo, in vitro, and in vivo nude mouse experiments to assess the underlying mechanisms of ROC1 in bladder cancer cells. The expression of the components of the sonic hedgehog (SHH) pathway was determined by western blot analysis. ROC1 expression in human tumors was evaluated by immunohistochemistry.Results: ROC1 overexpression promoted the growth of bladder cancer cells, whereas knockdown of ROC1 expression had the opposite effect in bladder cancer cells. Mechanistically, ROC1 was able to target suppressor of fused homolog (SUFU) for ubiquitin-dependent degradation, allowing Gli2 release from the SUFU complex to activate the SHH pathway. Furthermore, knockdown of SUFU expression partially rescued the ROC1 knockdown-suppressed SHH activity as well as cancer cell growth inhibition. In ex vivo experiments, tissue microarray analysis of human bladder cancer specimens revealed a positive association of ROC1 expression with the SHH pathway activity. Conclusion: This study demonstrated that dysregulation of the ROC1–SUFU–GLI2 axis plays an important role in bladder cancer progression and that targeting ROC1 expression is warranted in further investigations as a novel strategy for the future control of bladder cancer.

Background The regulator of cullins-1 (ROC1) is an essential subunit in the Cullin-RING ligase (CRL) protein complex and was shown to be critical in bladder cancer cell survival and malignant progression. This study aimed to explore the regulatory mechanism of ROC1 in bladder cancer malignant progression. Methods This study explored the underlying mechanisms using both in vitro and in vivo experiments. The expression of the components of Sonic Hedgehog (SHH) pathway was determined by western blotting analysis. ROC1 expression in human tumours was evaluated by immunohistochemical analysis. Results The data showed that ROC1 overexpression promoted growth of bladder cancer cells, whereas knockdown of ROC1 expression had an opposite effect in bladder cancer cells. Mechanistically, ROC1 was able to target SUFU for ubiquitin-dependent degradation, allowing the Gli2 release from the SUFU complex to activate SHH pathway. Furthermore, knockdown of SUFU expression partially rescue the ROC1 knockdown-suppressed SHH activity as well as cancer cell growth inhibition. At ex vivo, tissue microarray analysis of human bladder cancer specimens revealed an positive association of ROC1 expression with the SHH pathway activity. Conclusion The current study demonstrated the dysregulation of ROC1-SUFU-GLI2 axis played an important role in bladder cancer progression and targeting of ROC1 expression is warranted further investigation as a novel strategy for future control of bladder cancer.