Xin-Rong Zhao1,2, Ming-Chang Zhang3, Hua-Tao Xie1, Nan Ji2, Le-Tian Sun2. 1. Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China. 2. Department of Ophthalmology, The First Affiliated Hospital of Medical College, Shihezi University, Shihezi, Xin Jiang, China. 3. Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China. mingchangzhang@hotmail.com.
Abstract
OBJECTIVE: To investigate the role of p70S6K in the transdifferentiation of fibroblasts to myofibroblasts in pterygium tissue growth on the cornea. RESULTS: Quantitative real-time PCR and immunohistochemistry showed that p70S6K expression was higher in pterygium tissues than in normal conjunctival tissues. Higher p70S6K RNA expression levels were correlated with higher pterygium grades. Additionally, western blot analysis revealed that phosphorylated (activated) p70S6K (p-p70S6K) expression was significantly correlated with α-smooth muscle actin (α-SMA, a hallmark of transdifferentiation) expression in cultured human pterygium fibroblasts (HPFs). Furthermore, p70S6K knockdown and the specific mTOR inhibitor rapamycin decreased the expression levels of p-p70S6K and α-SMA in cultured fibroblasts from grade T3 pterygium. CONCLUSIONS: p70S6K activation promotes the transdifferentiation of pterygium fibroblasts to myofibroblasts. Thus, targeting p70S6K may be a useful strategy in the management of pterygium.
OBJECTIVE: To investigate the role of p70S6K in the transdifferentiation of fibroblasts to myofibroblasts in pterygium tissue growth on the cornea. RESULTS: Quantitative real-time PCR and immunohistochemistry showed that p70S6K expression was higher in pterygium tissues than in normal conjunctival tissues. Higher p70S6K RNA expression levels were correlated with higher pterygium grades. Additionally, western blot analysis revealed that phosphorylated (activated) p70S6K (p-p70S6K) expression was significantly correlated with α-smooth muscle actin (α-SMA, a hallmark of transdifferentiation) expression in cultured human pterygium fibroblasts (HPFs). Furthermore, p70S6K knockdown and the specific mTOR inhibitor rapamycin decreased the expression levels of p-p70S6K and α-SMA in cultured fibroblasts from grade T3 pterygium. CONCLUSIONS:p70S6K activation promotes the transdifferentiation of pterygium fibroblasts to myofibroblasts. Thus, targeting p70S6K may be a useful strategy in the management of pterygium.