Gene expression analysis in calcific tendinopathy of the rotator cuff

Abstract

We evaluated the expression of several genes involved in tissue remodelling and bone development in patients with calcifi c tendinopathy of the rotator cuff. Biopsies from calcifi ed and non-calcifi ed areas were obtained from 10 patients (8 women and 2 men; average age: 55 years; range: 40-68) with calcifi c tendinopathy of the rotator cuff. To evaluate the expression of selected genes, RNA extraction, cDNA synthesis and quantitative polymerase chain reaction (PCR) were performed. A signifi cantly increased expression of tissue transglutaminase (tTG)2 and its substrate, osteopontin, was detected in the calcifi c areas compared to the levels observed in the normal tissue from the same subject with calcifi c tendinopathy, whereas a modest increase was observed for catepsin K. There was also a signifi cant decrease in mRNA expression of Bone Morphogenetic Protein (BMP)4 and BMP6 in the calcifi c area. BMP-2, collagen V and vascular endothelial growth factor (VEGF) did not show signifi cant differences. Collagen X and matrix metalloproteinase (MMP)-9 were not detectable. A variation in expression of these genes could be characteristic of this form tendinopathy, since an increased level of these genes has not been detected in other forms of tendon lesions.

Interactions between osteopontin and vascular endothelial growth factor: Implications for skeletal disorders

“…The levels of OPN along with tissue transglutaminase increase in calcific tendinopathy without any change in the levels of VEGF in the calcified areas. This increase does not match other types of lesions [41].…”

Experimental studies on the biological effects of extracorporeal shock wave therapy on tendon models. A review of the literature

“…Nevertheless, we are not yet able to define how, in vivo, the ESWT acts on exposed tissues. They may provide mechanical and biological stimuli determining the activation of a complex network of molecules, including a large panel of cytokines and metalloproteinases 24,[35][36][37] .…”

Evaluation and Nonsurgical Management of Rotator Cuff Calcific Tendinopathy

“…4 Ischemic heart disease, hypertension, diabetes and thyroid disease are known associated medical conditions that seem to predispose patients to developing calcific tendinopathy for reasons not well understood. 5 There is a known correlation with calcific tendinopathy and endocrine disorders. These patients have an earlier onset of symptoms, a longer disease course, and ultimately undergo surgery more frequently than people that do not have these conditions.…”

“…5 It should also be mentioned again that there are a number of endocrine and vascular disorders that are associated with calcific tendinopathy.…”