Patched homolog 1 gene mutation (p.G1093R) induces nevoid basal cell carcinoma syndrome and non-syndromic keratocystic odontogenic tumors: A case report

Use of anteromedial thigh perforator flap and immunological implications of Gorlin-Goltz syndrome: a case study

Gorlin-Goltz syndrome is mainly characterised by the development of numerous multicentric and relapsing cutaneous basal cell carcinomas (BCCs). A major problem for patients with Gorlin-Goltz syndrome is the large amount of BCCs that can invade the deep underlying structures, especially the face. Here, we describe the case of a 23-year-old male affected by Gorlin-Goltz syndrome. He had recurrent BCCs on a hairless scalp and dorsum since he was 17 years old and underwent four surgical procedures to excise BCCs, including a reconstruction with anteromedial thigh perforator flap. For each of the surgical procedures, a phenotypic study on peripheral blood mononuclear cells using flow cytometry was performed on the same day of surgery, and on days 7, 14 and 21 after surgery. The role of the tumour-specific cytolytic immune response as a potential future treatment of syndromic BCCs and its trend in relation to surgical ablation of large portions of tumour tissue was examined, and the cosmetic and therapeutic results are shown.

Molecular Signaling in Benign Odontogenic Neoplasia Pathogenesis

Several molecular pathways have been shown to play critical roles in the pathogenesis of odontogenic tumors. These neoplasms arise from the epithelial or mesenchymal cells of the dental apparatus in the jaw or oral mucosa. Next generation genomic sequencing has identified gene mutations or single nucleotide polymorphisms associated with many of these tumors. In this review, we focus on two of the most common odontogenic tumor subtypes: ameloblastoma and keratocystic odontogenic tumors. We highlight gene expression and protein immunohistological findings and known genetic alterations in the hedgehog, BRAF/Ras/MAPK, epidermal growth factor receptor, Wnt and Akt signaling pathways relevant to these tumors. These various pathways are explored to potentially target odontogenic tumors cells and prevent growth and recurrence of disease. Through an understanding of these signaling pathways and their crosstalk, molecular diagnostics may emerge as well as the ability to exploit identified molecular differences to develop novel molecular therapeutics for the treatment of odontogenic tumors.

Skeletal stigmata as keys to access to the composite and ancient Gorlin-Goltz syndrome history: The Egypt, Pompeii and Herculaneum lessons

There are several genetic diseases with a wide spectrum of congenital bone stigmata in association to cutaneous and visceral benign and malignant neoplasms. Gorlin-Goltz syndrome, also named nevoid basal cell carcinoma syndrome, is an autosomal dominant systemic disease with almost complete penetrance and high intra-familial phenotypic variability, caused by germline mutations of the gene PTCH1. The syndrome is characterized by unusual skeletal changes and high predisposition to the development of multiple basal cell carcinomas, odontogenic keratocysts tumors and other visceral tumors. The Gorlin syndrome, clinically defined as distinct syndrome in 1963, existed during Dynastic Egyptian times, as revealed by a costellation of skeletal findings compatible with the syndrome in mummies dating back to 3000years ago and, most likely, in the ancient population of Pompeii. These paleogenetic and historical evidences, together with the clinical and biomolecular modern evidences, confirm the quite benign behavior of the syndrome and the critical value of the multiple and synchronous skeletal anomalies in the recognition of these rare and complex genetic disease.

Skeletal and cranio-facial signs in Gorlin syndrome from ancient Egypt to the modern age: sphenoid asymmetry in a patient with a novel PTCH1 mutation

Gorlin syndrome is an autosomal dominant disorder linked to PTCH1 mutation, identified by a collection of clinical and radiologic signs. We describe the case of a family in which father and son fulfilled clear cut diagnostic criteria for Gorlin syndrome including multiple basal cell carcinomas, keratocystic odontogenic tumors, atypical skeletal anomalies and a novel PTCH1 germline mutation (c.1041delAA). Craniofacial and other skeletal anomalies displayed at 3D and helical CT scan were: macrocephaly, positional plagiocephaly, skull base and sphenoid asymmetry, bifidity of multiple ribs and giant multilocular odontogenic jaw cysts. Extensive multilamellar calcifications were found in falx cerebri, tentorium, falx cerebelli and in the atlanto-occipital ligament. The inclusion of bifid ribs as a novel major criteri may be useful for the recognition and characterization of misdiagnosed cases.

Proteomic analysis of PTCH1+/- fibroblast lysate and conditioned culture media isolated from the skin of healthy subjects and nevoid basal cell carcinoma syndrome patients

BACKGROUND

The pathogenesis underlying the increased predisposition to the development of basal cell carcinomas (BCCs) in the context of Gorlin-Goltz syndrome is linked to molecular mechanisms that differ from sporadic BCCs. Patients with Gorlin syndrome tend to develop multiple BCCs at an early age and present with tumors of non-sun-exposed skin. The aim of this study was to compare the proteomic profile of cultured fibroblast and fibroblast conditioned culture media of PTCH1+ and nonmutated fibroblasts.

RESULTS

Proteomic analysis was performed using Surface-Enhanced Laser Desorption/Ionization Time-of-Flight mass spectrometry in PTCH1+ fibroblast conditioned media isolated from not affected sun-protected skin areas of Gorlin patients and from healthy subjects. 12 protein cluster peaks, >5 kDa, had significant differences in their peak intensities between PTCH1+ and PTCH1- subject groups. We detected a strongly MMP1 overexpression in PTCH1+ fibroblasts obtained from NBCCS patients with respect to healthy donors.

CONCLUSION

Protein profiles in the fibroblast conditioned media revealed statistically significant differences between two different types (missense versus nonsense) of PTCH1 mutations. These differences could be useful as signatures to identify PTCH1 gene carriers at high risk for the development of NBCCS-associated malignancies and to develop novel experimental molecular tailored therapies based on these druggable targets.

Diagnostic and pathogenetic role of café-au-lait macules in nevoid basal cell carcinoma syndrome

Café au lait spots (CALS) are common dermatologic findings that can at the same time arise in a variety of pathologic conditions such as Neurofibromatosis type 1 (NF1), together with numerous hereditary syndromes for which they represent either diagnostic criteria or associated elements (McCune Albright, Silver-Russell, LEOPARD, Ataxia-Telangiectasia). A review of the literature also revealed two cases of association with NBCCS. We report here the case of a female proband with CALS associated to Nevoid Basal Cell Carcinoma Syndrome (NBCCS) with known PTCH1 germline mutation (C.1348-2A>G) who had been misdiagnosed with NF1 in her childhood because of 5 CALS and cutaneous nodules. The patient presented a giant cell tumor of the skin, palmar and calcaneal epidermoidal cystic nodules, odontogenic keratocystic tumors and deformity of the jaw profile. Her family history brought both her brother and father to our attention because of the presence of KCOTs diagnosed at early age: after genetic testing, the same PTCH1 germline mutation was identified in the three family members. Clinical criteria are used for discerning NF1 diagnosis (size, number and onset age), while there are no definite guidelines concerning CALS except for their presence. In our experience, we have noted an association of CALS with NBCCS; this seems interesting because we already know clinical criteria are a dynamic entity and can be modified by epidemiologic evidences.

Novel PTCH1 mutations in patients with keratocystic odontogenic tumors screened for nevoid basal cell carcinoma (NBCC) syndrome

Keratocystic odontogenic tumors (KCOTs) are cystic tumors that arise sporadically or associated with nevoid basal cell carcinoma syndrome (NBCCS). NBCCS is a rare autosomal dominantly inherited disease mainly characterized by multiple basal cell carcinomas, KCOTs of the jaws and a variety of other tumors. PTCH1 mutation can be found both in sporadic or NBCCS associated KCOTs. The aim of the current study was to assess whether a combined clinical and bio-molecular approach could be suitable for the detection of NBCCS among patients with a diagnosis of keratocystic odontogenic tumors (KCOTs). The authors collected keratocystic odontogenic tumors recorded in the database of the Pathology Department of the University of Modena and Reggio Emilia during the period 1991–2011. Through interviews and examinations, family pedigrees were drawn for all patients affected by these odontogenic lesions. We found out that 18 of the 70 patients with KCOTs and/or multiple basal cell carcinomas actually met the clinical criteria for the diagnosis of NBCCS. A wide inter- and intra-familial phenotypic variability was evident in the families. Ameloblastomas (AMLs) were reported in two probands that are also carriers of the PCTH1 germline mutations. Nine germline mutations in the PTCH1 gene, 5 of them novel, were evident in 14 tested probands. The clinical evaluation of the keratocystic odontogenic tumors can be used as screening for the detection of families at risk of NBCCS. Keratocystic odontogenic lesions are uncommon, and their discovery deserves the search for associated cutaneous basal cell carcinomas and other benign and malignant tumors related to NBCCS.