Avaliação da expressão gênica de metaloproteinases de matriz e seus inibidores em colesteatomas por amplificação de ácidos nucleicos

Abstract

Acqui red middle ear cholesteatoma is a benign keratinizing hyperproliferative squamous epithelial lesion that may result in the destruction of the bone structures surrounding the temporal bone. Recent studies show that variations in cellular production of matrix metalloproteinases (MMPs) and their specific inhibitors (TIMPs) contribute to the pathophysiology of cholesteatoma. Objective:This study aims to analyze the use of RNA amplification tests to evaluate the expression of MMP and TIMP isoforms in cholesteatomas and their correlation with disease severity. Materials and Methods:This is a prospective study. Nineteen cholesteatoma cases at different stages were selected. RNA collected from biopsy specimens was submitted to reverse transcription polymerase chain reaction (RT-PCR) for semiquantitative amplification of MMP2, MMP3, MMP9, MMP13 and TIMP1.Results: Six cholesteatomas were positive for at least one of the studied genes. Four samples amplified a single gene (MMP2 or MMP13) and two samples amplified three genes (MMP2, TIMP1 and MMP3 or MMP13). No sample amplified MMP9. Conclusion:RT-PCR can be used to assess MMP and TIMP gene expression in cholesteatomas despite technical difficulties. Gene expression profiles could not be related to disease severity. Braz J Otorhinolaryngol. 2012;78(3):116-21. ORIGINAL ARTICLE BJORL

Comparison of Tissue Factors in the Ontogenetic Aspects of Human Cholesteatoma

“…However, the numbers of MMP-2-positive cells increased in both groups of patients compared with the control group. These results are in an agreement with Banerjee et al [ 66 ], who showed no up-regulation of MMP-2 and MMP-9 compared with deep meatal skin, and with Rezende et al [ 67 ], whose study demonstrated that MMP-9 detected with the PCR method was negative in cholesteatoma samples. In addition, our study revealed that many samples of cholesteatoma were also negative or weakly stained for MMP-9 immunohistochemically.…”

Expression of MMP-14 and its role in bone destruction in middle ear cholesteatoma: A prospective observational study

“…[ 9 ] Its substrates include collagen I, II, I to II, fibronectin, CD44, and so on. It can also activate other members of the MMP family, [ 10 ] induce angiogenesis, [ 5 ] and enhance cell metastasis. [ 11 ] At present, it is speculated that MMP-14 leads to bone invasion of cholesteatoma through the following ways: Activation of MMP-2: MMP-2 is type IV collagenase, which can degrade laminin and fibronectin of basement membrane.…”