CCN2 and diabetic kidney disease: Even though intravenous administration of CTGF antibody (FG-3019) in patients with diabetic kidney disease significantly decreases albuminuria without obvious adverse effects, the safety concerns, such as the interference with CTGF-dependent skeletogenesis, still exist as CTGF is involved in more complex biological processes, such as angiogenesis, chondrogenesis and osteogenesis.