TGFβ3 expression in non-syndromic orofacial clefts

Background: Genetic studies have demonstrated that non-syndromic cleft is composed of two separate entities - cleft palate only (CPO) and cleft of tip, alveolus with or without cleft palate (CL +/- P) -, both have a heterogeneous genetic background and environmental factors contribute to the onset of these malformations. Previous studies have shown that TGF beta 3 could be involved in these diseases, but no conclusive results have been reached. Purpose: In order to detect if TGF beta 3 has a role in cleft diseases, a series of non-syndromic cleft patients and controls are analyzed for TGF beta 3 protein expression. Material and methods: Forty-three non-syndromic cleft patients and 21 unaffected subjects were involved in this study. Paraffin-embedded specimens were matched with the TGF beta 3 antibody and then scanned with a computerized image analyzer. TGF beta 3 was found to be absent (less than 10%), moderate (from 10% to 30%) and highly expressed (higher than 30%) in epithelium (EP), minor palatal salivary gland (GL) and fibres of elevator palati muscle (MU). Data was statistically analyzed with a Kruskal-Wallis test. Results: Only GL and EP have a statistically significant lower expression in non-syndromic cleft compared to unaffected subjects. A subsequent comparison between CL P and CPO groups demonstrates a statistically significant difference only for GL, with a tower expression in GL of CPO patients. Conclusions: TGF beta 3 is decreasingly expressed in GL of unaffected CL +/- P and CPO patients and thus further strength is given to a pathogenetic role of TGF beta 3 in the onset of clefts. (C) 2006 Elsevier Ireland Ltd. All rights reserved.