Mutations in the patched 1 (PTCH1) gene are the main genetic alteration reported in sporadic and nevoid basal cell carcinoma-associated odontogenic keratocyst (OKC).
While various genetic alterations, such as PTCH1 mutation and loss of heterozygosity in tumor suppressor genes, have been reported, the molecular background of OKC is not well-understood.
It is known that some sporadic OKCs harbor PTCH1 mutations, and via the dissection of cyst epithelium, these mutations were demonstrated to occur much more frequently than previously thought.
We describe a Gorlin syndrome (GS) case with two different second hit mutations of PTCH1, one in a keratocystic odontogenic tumor (KCOT) and the other in an ovarian leiomyoma.
In addition, a total of 204 PTCH1 mutations (187 mutations from 210 cases with NBCCS-associated and 17 mutations from 57 cases with sporadic KCOTs) were compiled from 78 published papers.
Considering that alterations in this pathway have been described in sporadic and nevoid basal cell syndrome-associated KOT, we tested the hypothesis that OOC is also associated with loss of heterozygosity (LOH) of the PTCH gene.
The aim of the present study was to investigate the expression of PTCH1 first exons in OKC tumors to shed light on scenery whereby PTCH1 coordinates OKC tumorigenesis.
The immunoprofile of odontogenic keratocyst (keratocystic odontogenic tumor) that includes expression of PTCH, SMO, GLI-1 and bcl-2 is similar to ameloblastoma but different from odontogenic cysts.