Expression of Collagen Types I, II and III in Juvenile Angiofibromas

Abstract

Extracellular matrix components have rarely been the focus of interest in juvenile angiofibroma (JA) studies. Although JAs are known to be collagen-rich tumours, single collagens have not been analysed so far. This investigation aimed to study the expression of the fibrillar collagen types I, II and III in JAs using quantitative RT-PCR (n = 15), Western blot analysis (n = 7) and immunohistochemical staining (n = 9). Nasal mucosa (NM) specimens were used as control tissues. ELISA investigation (n = 3) was performed to determine the concentration of C-terminal propeptide of type I collagen in blood serum before and after JA resection. Quantitative RT-PCR found significantly elevated Col1A1 (p < 0.001), Col1A2 (p < 0.001) and Col3A1 (p < 0.001) mRNA levels in JAs, compared with NM. Western blot analysis and immunhistochemical staining proved that there is a significant collagen type I and III protein expression in JAs. In none out of 3 patients, ELISA investigation found evidence for elevated concentrations of C-terminal propeptide of type I collagen before tumour resection, compared with postsurgical measurements. Results of the findings using quantitative RT-PCR, Western blot analysis and immunohistochemistry determined that type II collagen is practically absent in JAs. Based on these findings, type I and III collagen are confirmed as being major components of the extracellular matrix in JAs. However, our findings are not encouraging as regards the use of C-terminal Col I propeptid as a suitable serum tumour marker. Our findings confirming that collagen type II expression is practically absent in JAs refutes the theory that JAs originate in cartilage tissue.

Markers of vascular differentiation, proliferation and tissue remodeling in juvenile nasopharyngeal angiofibromas

“…On the contrary, ST3 exhibits a collagenolytic function against the native α3 chain of collagen VI (38). Prominent collagen-type VI expression has been previously described in JNA vessels, possibly exerting growth stimulatory effects on endothelial cells (6,7).…”

“…Although several mmPs have been described in JNAs (37), there have been no reports of ST3 expression in this particular type of tumor. ST3 differs from other mmPs, since its mature form is incapable of cleaving type I and III collagens, the major components of the stromal and vascular ECm in JNAs (7). On the contrary, ST3 exhibits a collagenolytic function against the native α3 chain of collagen VI (38).…”

“…The presence of proteins such as merosin (laminin α2) and collagens type VI and 1A2, which were recently described as being highly expressed in JNA vessels, is suggestive of vessels in an early developmental vascular differentiation state (5)(6)(7). Notably, merosin and type VI collagen were also elevated in several types of cancer and in proliferative hemangiomas.…”

“…Notably, merosin and type VI collagen were also elevated in several types of cancer and in proliferative hemangiomas. The latter are vascular lesions characterized by abnormal excessive endothelial cell proliferation (5)(6)(7)(8)(9).…”

Endothelin-1 and type III collagen alterations in the heart of rats following cisplatin-induced toxicity

“…Type III collagen is a critical collagen that comprises extensible connective tissue, a crucial component of the extracellular matrix in the heart (26,27), and appears to be involved in cardiac diseases. Myocardial fibrosis is the key factor that regulates left ventricular (LV) diastolic function, and collagen type III appears to be associated with cardiac fibrosis (28).…”