OBJECTIVETo investigate the expression of tenascin-C (Tn-C) in keloid and hyperplastic scar (HS).

METHODSTissue samples were harvested from 10 patients with keloid and 10 with HS (6 - 10 months) and from the skin of 5 adult healthy volunteers. The expression of Tn-C in these samples was determined with immunohistochemistry method.

RESULTSThere was scarce expression of Tn-C in the skin tissue in adult healthy volunteers, and it was only present in the dermal papillae at the dermis epidermis conjunctions and partly in the blood vessels and skin appendages adjacent to the basement membrane. There was enhanced expression of Tn-C in the dermal scar tissue and skin appendages in both keloid and HS, especially in keloid, which exhibited a diffused pattern in the tissue. When compared with that in normal skin, the Tn-C expression in the normal skin adjacent to the keloid was enhanced markedly, but not in the normal skin near HS tissue.

CONCLUSIONThere was increased Tn-C expression in keloid and HS (6 - 10 months).

Cicatrix, Hypertrophic ; metabolism ; Female ; Humans ; Immunohistochemistry ; Keloid ; metabolism ; Male ; Skin ; chemistry ; Tenascin ; analysis

To explore the role of tenascin (TN) and fibronectin (FN) in the pathophysiology of nasal polyps (NP), the expression of TN and FN in NP from 34 patients and inferior turbinates from 20 patients with deviation of nasal septum was immunohistochemically studied. In patients with NP, the relations between expression and histopathological features, eosinophils (EOS) infiltration, clinical staging and the size of NP were analyzed. Our study showed that the gray score of TN and FN expression was 163.10 +/- 10.54 and 163.24 +/- 11.52 in NP respectively, whereas it was 175.49 +/- 9.29 and 173.93 +/- 7.92 in inferior turbinates respectively. The difference between two groups was significant (P < 0.01). The expression of TN and FN in endematous type was significantly stronger than that in cystic and glandular type and fibrous type (P < 0.05). The association between FN expression and EOS infiltration was significant (r = -0.60, P < 0.01). The expression of TN and FN did not correlate with clinical staging and size (P > 0.05). It was suggested that abnormal ECM might contribute to proliferation of epithelia, accumulation of EOS and edema formation, thereby causing development of NP.
Adolescent ; Adult ; Child ; Eosinophils ; pathology ; Extracellular Matrix ; metabolism ; Female ; Fibronectins ; analysis ; metabolism ; Humans ; Male ; Middle Aged ; Nasal Polyps ; metabolism ; pathology ; Tenascin ; analysis ; metabolism ; Turbinates ; metabolism

BACKGROUNDTreating metastatic osteosarcoma has been challenged in past decades. Extracelluar matrix (ECM) proteins play an important role in the progression of osteosarcoma as they are pivotal components of the tumor microenvironment. Here, we identified potential genes belonging to the ECM and characterized the roles of these genes in the progression of osteosarcoma and their association with outcomes.

METHODSOsteosarcoma parental cell line MG63 and its derivative MG63-A1 with a high metastatic potential underwent oligonucleotide microarray analysis. Gene ontology analysis was used to screen deregulated genes between the 2 cell lines which were either upregulated or downregulated by more than 4 fold, particularly focusing on mRNAs encoding extracellular matrix proteins. The expression of resulting candidate genes was then validated by reverse transcription-PCR for mRNA expression as well as Western blotting for protein expression. Immunohistochemistry was performed on 37 osteosarcoma specimens to examine the potential role of the candidate genes in a clinical context.

RESULTSMicroarray data and gene ontology analysis showed that Tenascin-C, a critical component of the ECM, is significantly down-regulated in the highly metastatic cell line MG63-A1 compared with the parental osteosarcoma cell line MG63-wt. This finding was validated at mRNA and protein levels. Immunohistochemical analysis found that Tenascin-C is located in the intercellular space in osteosarcoma specimens. Furthermore, low-grade Tenascin-C expression (less than 20%) in osteosarcoma specimens was associated with poor survival.

CONCLUSIONSTenascin-C expression level correlates with the survival of osteosarcoma patients. Its biological functional role and underlying molecular mechanisms in the progression of osteosarcoma needs further investigation.

Adolescent ; Adult ; Bone Neoplasms ; metabolism ; mortality ; Cell Line, Tumor ; Child ; Female ; Humans ; Male ; Oligonucleotide Array Sequence Analysis ; Osteosarcoma ; metabolism ; mortality ; Prognosis ; RNA, Messenger ; analysis ; Tenascin ; analysis ; genetics

Pathogenesis of the abdominal aortic aneurysm has been attributed to neovascularization of the aortic wall. However, it is not clear whether angiogenesis persists in the aneurysm. In sections of aneurysms, we determined the immunohistochemical distributions of the alpha v beta 3 integrin, tenascin and endothelial nitric oxide synthase (eNOS), which are markers respectively, of angiogenesis, matrix remodeling and vasoregulatory function. In addition, we used reverse transcription followed by in situ PCR, to determine the distribution of alpha v mRNA. All aneurysm specimens exhibited extensive increases of wall vascularization as compared with the control aortic wall, and showed the presence of perivascular inflammatory exudates containing macrophages and lymphocytes. The neovascularization consisted of thick-walled vessels in the media and adventitia, and capillaries in the subintima. The majority of vessels stained positively for the alpha v beta 3 antigen and eNOS. Tenascin was deposited as bands that circumscribed thick-walled vessels. The distribution of av mRNA was extensive and was positive even in those vessels that failed to stain for the alpha v beta 3 protein. No staining was evident in control aortas for the alpha v beta 3 antigen, tenascin or alpha v mRNA. The upregulation of av mRNA and the alpha v beta 3 integrin in blood vessels surrounded by a matrix expressing tenascin, indicates that angiogenesis is an ongoing process in the mature aortic aneurysm.
Adult ; Aorta, Abdominal/immunology/pathology ; Aortic Aneurysm, Abdominal/*pathology ; Biological Markers/analysis/metabolism ; Female ; Humans ; Integrin alphaVbeta3/analysis/genetics/metabolism ; Male ; Neovascularization, Pathologic/genetics/*metabolism ; Nitric-Oxide Synthase/analysis/metabolism ; RNA, Messenger/analysis/metabolism ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, P.H.S. ; Tenascin/analysis/metabolism