Abstract: To study the role of FoxO3a and MMP2 in chronic thromboembolic pulmonary hypertension (CTEPH). Methods Twenty patients with CTEPH admitted to the China-Japan Friendship Hospital during 2018.1-2018.12 were enrolled in this study. Pulmonary vascular smooth muscle cells (VSMCs) were obtained from 5 cases of 20 surgical specimens. Pulmonary artery trunk of donor was used as a control. The expression of FoxO3a and MMP2 in the surgical specimens and VSMCs from the normal group and disease group were observed by immunohistochemistry and Western Blot. Results The integral absorbance value (IA) of FoxO3a in the CTEPH group was: 3269±338, which was significantly increased compare with normal group 420±46 (P<0.01); the IA of MMP2 respectively was 1799±139, 4936±521 (P<0.01); The expression of MMP2 and FoxO3a in the CTEPH group was significantly increased compare with normal group (P<0.05). Conclusions Overexpression of FoxO3a/MMP2 may be involved in the vascular remodeling, thus accelerating the occurrence and development of CTEPH.

Key words: chronic thromboembolic pulmonary hypertension, FoxO3a, MMP2, vascular smooth muscle cells