Expression of Cell-Cell Adhesion Molecules in Matrical Tumors of Hairs, Nails, Teeth and Pituitary Gland - Adhesion Molecules - page 300

Table 2 β -catenin mutations and nuclear expression in matrical tumors of the hair, teeth,
nails and pituitary gland

Tissue Matrical tumor β-catenin Nuclear Reference

mutations β-cat (IHC)

Hair Pilomatricoma Frequent In basaloid cells Chan et al . 1999

Matricoma Not known Not known

Pilomatrix carcinoma Frequent In basaloid cells Hassanein and Glanz

2004

Lazar et al . 2005

Melanocytic matricoma Not known In basaloid cells Peralta Soler et al . 2007

Teeth Calcifying odontogenic Frequent In basaloid cells Sekine et al . 2003

cyst

Ameloblastoma Infrequent In basaloid cells Sekine et al . 2003

Kumamoto and Ooya

2005

Nails Onychomatricoma Not known Negative Burchette et al . 2008

Pituitary Craniopharyingioma Frequent In basaloid cells Sekine et al . 2001

gland

h e majority of matrical tumors from hard structures exhibit β-catenin mutations and/or nuclear translocation
of β-catenin. However, there are dif erences among tumors, and subcellular distribution, mutations and signaling
activation of β-catenin have not been studied in many of this group of matrical tumors.

Matrical Nail Tumors

Onychomatricoma is an exceedingly rare nail tumor with distinctive biphasic
epithelial and stromal tissues. h e architectural characteristics include proximal
cavitated invaginations of nail matrix epithelium into the stroma, and distal dermal
protrusions perforating the nail plate (Baran and Kint 1992). Electron microscopy
and immunohistochemistry (Perrin et al. 2002) studies support the origin of the
tumor from the nail matrix, a structure containing keratinocytes, Langerhans
cells, melanocytes and Merkel cells. Although very few cases of onychomatricoma
have been reported, there is a proposal to subclassify them into predominantly
epithelial unguioblastomas, most closely associated with trichoblastomas and
ameloblastomas, and predominantly stromal tumors called unguioblastic i bromas
(Ko et al. 2004).

Matrical Tooth Tumors

Tumors of the teeth with matrical features include the calcifying odontogenic
cyst (Gorlin cyst, dentinogenic ghost cell tumor, calcifying ghost cell odontogenic
cyst) and the ameloblastoma and its variants. Calcifying odontogenic cyst is a
predominantly intraosseous neoplasm of the jaw that includes benign, purely cystic