Increased Serum KLF4 in Severe Atheromatosis and Extensive Aneurysmal Disease.

BACKGROUND: Krüppel-like factor 4 (KLF4) is known to preserve vascular homeostasis. In the present study, we sought to correlate serum KLF4 levels with arterial aneurysm size and their clinical presentation. We also explored the association between serum KLF4 levels and the severity of extracranial carotid and peripheral arterial disease. METHODS: Patients undergoing surgery for various forms of atheromatosis (ATH group) or for arterial aneurysm repair (AA group) were eligible for inclusion. KLF4 levels were measured via enzyme-linked immunosorbent assay. RESULTS: Patients in the atheromatic and aneurysmal groups had significantly higher serum KLF4 levels compared with controls. Patients with permanent end-organ damage (ATH3) had higher serum KLF4 (6.96 ± 0.75 pg/mL) compared with patients with asymptomatic internal carotid stenosis >70% or claudication (ATH1) (2.76 ± 0.68 pg/mL; mean difference [MD], -4.20; 95% confidence interval [95% CI], -5.35 to -3.04; P < 0.01) and those with transient ischemic attack or rest pain (ATH2) (4.47 ± 1.08 pg/mL; MD, -2.48; 95% CI, -3.76 to -1.21). Furthermore, patients with an asymptomatic aneurysm of a diameter 250-300% of that of the normal artery (AA1, 5.01 ± 1.08 pg/mL) had considerably lower serum KLF4 compared with those suffering from either a symptomatic aneurysm or an asymptomatic aneurysm of a diameter >350% of that of normal artery (AA3, 6.63 ± 1.92 pg/mL; MD, -2.61; 95% CI, -5.04 to -0.18; P < 0.01). CONCLUSIONS: Serum KLF4 levels are significantly increased in patients with end-organ damage related to atheromatosis as well as those with extensive aneurysmal disease.