Expression of Gene Runx2, Wnt and OPG in Palate Cleft Reconstruction Material

Abstract

Introduction. Facial morphogenesis occurs from the fourth to the twelfth gestation week, when the cells from nerve crest migrate to the region of face, forming the primary palate. The cleft palate is an abnormality in embryogenesis period, which is characterized by the absence of fusion of palatal shelves. The incidence of cleft lip and palate is one in 700 live births. In recent years the effect of different genes and signaling molecules, including Runx2, Wnt3 and OPG have been studied in the development of cleft palate, because these substances are considered to be regulators of pathogenesis responsible for formation of bone and cartilage tissue and particularly the bone. Aim of the Study. The aim of the work was to evaluate the expression of Runx2, Wnt3 and OPG in palate bone and nasal cartilage for children with cleft palate. Material and methods. Eleven bone and cartilage samples were obtained from 21 children of the lip, soft and hard palate correction surgery. All the patients were diagnosed with clefts of the lip, alveolar process of maxilla, and palate. In the tissue sections using the immunohistochemistry method (IMH), were determined Runx2 (code: AB192256, 1: 250, Abcam GB, rabbit), Wnt3 (code: AB1992, 1: 800, Abcam GB, rabbit), and OPG (code: A0611, 1: 100, The Orbit USA, rabbit) local expression. We used a semi-quantitative census method for quantifying the positive structures. Results. Runx2 expression was observed in five patient bone tissue samples and six patient cartilage tissue samples. Of the Runx2 positive bone tissue, in one case we observed occasional, in two cases- few, in one case- moderate to numerous and in one case numerous positive osteocytes while in tissue of cartilage in two cases we observed few, in one case- few to moderate, in two cases moderate, and in one case numerous positive chondrocytes. A significant difference in Wnt3 expiation was observed between bone and cartilage tissues. Wnt3 expressing chondrocytes were observed in all samples, where in one case- occasional, in three cases few, in one case-moderate, and in six cases-numerous positive cartilage cells were observed. The expression of the gene in the bone was observed in nine cases, which contained mostly occasional or few positive structures, except in three cases where in one Wnt3 was marked by few to moderate and in two cases numerous positive osteocytes. OPG expression was observed in all samples, but in the cartilage, the expression was more pronounced. In the cartilage in seven cases, there were numerous positive chondrocytes, in one case- few to moderate, in two cases moderate to numerous and in one case few to moderate number of chondrocytes. OPG showed variable expression. In four cases, we observed occasional to few, in one case few to moderate, in one case- moderate, in one case moderate to numerous and in four cases numerous positive bone cells. Conclusion. Cartilage tissue expresses significantly more Runx2, Wnt3 genes and OPG proteins, indicating a greater compensatory tissue capacity. In the case of palate clefts, the high expression of Wnt3 and OPG and lower expression of Runx2 could indicate a significant tissue proliferation which predominates over mineralization and ossification processes.