Expression of metalloproteinases and their tissue inhibitors in gingiva affected by hereditary gingival fibromatosis: analysis of three cases within a family

Fibroblasts Collagen Production and Histological Alterations in Hereditary Gingival Fibromatosis

Hereditary gingival fibromatosis is a disorder for which the etiology remains unknown. We aimed to evaluate the fibroblasts and histological alterations to give new clues. A father and a daughter of a family showing gingival hereditary fibromatosis were treated, and gingival biopsies were obtained. A histological study revealed dense fibrous tissue, basal lamina disruption, and epithelial cell migration into the connective tissue. Fibroblasts were cultured from the father and daughter and compared with those from a healthy control patient. The results of the biochemical analysis showed increased collagen synthesis, reduced antioxidant CoQ₁₀ content, and high levels of lipid peroxidation. Additionally, fibroblasts culture incubation with the oxidant H₂O₂ increased collagen levels that have been reduced by the addition of the antioxidant CoQ₁₀. We conclude that some fibroblasts metabolic alterations play a significant role in initiating and maintaining persistent fibrotic tissue. Oxidative stress influences the fibroblasts collagen production and could play a particular role in the pathogenesis of hereditary gingival fibromatosis.

Hereditary gingival fibromatosis: a three-generation case and pathogenic mechanism research on progress of the disease

BACKGROUND

Hereditary gingival fibromatosis (HGF) is a rare benign disorder characterized by progressive overgrowth of gingiva. Although the clinical and histopathologic characteristics of HGF are explicit, the pathogenic mechanism remains unclear. The goal of this article is to describe a three-generation HGF case and discuss the diagnosis, treatment, and inheritance of the disease. The known cellular and molecular features of HGF are also emphasized.

METHODS

Family and medical histories of the patients were recorded, and a series of preliminary examinations, including clinical, histologic, radiographic, and gene examination, were performed to make a diagnosis and learn about the genetic characteristics. An all-quadrant flap surgery was performed to remove excess gingiva, and orthodontic treatment was undertaken to help tooth eruption. Recent advances were reviewed for further knowledge of genetic, cellular, and molecular features of HGF.

RESULTS

The patient's manifestations and examinations showed a typical HGF characteristic. There was no recurrence after surgery, and the premolars and molars erupted to bite plane. Genetic studies have found several gene mutations involved in HGF. Only the son-of-sevenless-1 gene is identified. Multiple molecular factors, such as transforming growth factor-β and matrix metalloproteinases, participate in HGF, regulating the extracellular matrix.

CONCLUSIONS

Surgical intervention is the usual treatment of HGF, but patients still have to deal with the risk of recurrence. Once the correlations between gene mutations, molecular changes, histology, and clinical situation are clear, they can be applied to clinical application, providing novel methods for disease prognosis and diagnosis and targets for disease prevention and treatment.