Rho-associated protein kinase (ROCK) is a well-characterized effector of Rho GTPase. The Rho/ROCK signaling pathways contribute to a wide range of fundamental cell functions, such as cell adhesion, motility, proliferation, differentiation, and apoptosis. Due to its role in controlling a wide spectrum of biological events, ROCK has been intensively investigated as an important therapeutic target in a wide range of diseases including vascular disease, cancer, neuronal degenerative disease, asthma, and glaucoma. One ROCK inhibitor, fasudil, was approved for the treatment of cerebral vasospasm in 1995. In 2014, another ROCK inhibitor, ripasudil, was approved in Japan for the treatment of glaucoma and ocular hypertension. These monumental achievements have opened the pathway towards the clinical application of ROCK inhibitor as a therapeutic modality in the field of ophthalmology.

In addition to glaucoma, the involvement of ROCK signaling has been researched in other eye diseases such as corneal endothelial disease, cataract, age-related macular degeneration, and proliferative vitreous retinopathy. Thus, there is growing evidence that ROCK inhibitor might be a promising therapeutic modality in various eye diseases.

Therefore, we became interested in reports on the involvement of ROCK signaling in pathological situations and the possible application of ROCK inhibitor as a drug for treating eye-related disease. This special issue will provide a platform for readers to discover the importance and possible future application of ROCK inhibitor as a cross-sectional topic.

Potential topics include but are not limited to the following:

• Diseases: corneal endothelial disease, cataract, age-related macular degeneration, and proliferative vitreous retinopathy
• The involvement of Rho/ROCK signaling in eye diseases
• The feasibility of ROCK inhibition for treating eye diseases
• The application of ROCK inhibitor as adjunctive drug for eye surgery
• Clinical data pertaining to ROCK inhibitor eye drops in glaucoma patients