MYC gene numerical aberrations in actinic keratosis and cutaneous squamous cell carcinoma.
BACKGROUND
The genetic alterations that drive the transition from actinic keratoses (AKs) to cutaneous squamous cell carcinomas (SCCs) have not been defined precisely. Amplification and/or overexpression of the MYC proto-oncogene have been demonstrated in several human, malignant tumours including head and neck SCCs.


OBJECTIVE
To evaluate the presence of MYC genomic aberrations in both AKs and SCCs.


METHODS
Skin biopsy specimens corresponding to AKs, SCCs and control samples were included in two paraffin-embedded tissue microarrays. MYC cytogenetic profile was evaluated by fluorescence in situ hybridization (FISH). The results obtained were compared with MYC immunohistochemical expression.


RESULTS
Twenty-three AKs and 30 SCCs were evaluated. MYC numerical aberrations were observed in eight of 23 (35%) AKs and 19 of 30 (63%) SCCs (P = 0.05). MYC numerical aberrations were more frequent in moderately to poorly differentiated SCCs (77%) when compared with well-differentiated SCCs (25%; P = 0.027). A significant association between copy number gains of MYC by FISH analysis and MYC protein expression was demonstrated.


CONCLUSIONS
MYC gains and amplifications are frequent cytogenetic abnormalities in SCCs and may play a relevant role in promoting SCC undifferentiation and tumoral progression.
Toll
A
A
Department of Dermatology, IMIM Hospital del Mar, Pg. 08003 Barcelona, Spain. 93828@imas.imim.es
Salgado
R
R
Yébenes
M
M
Martín-Ezquerra
G
G
Gilaberte
M
M
Baró
T
T
Solé
F
F
Alameda
F
F
Espinet
B
B
Pujol
R M
RM
D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D002869:Chromosome Aberrations; D018450:Disease Progression; D005260:Female; D016259:Genes, myc / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D055623:Keratosis, Actinic / Q000235:genetics* / Q000473:pathology; D008297:Male; D046228:Microarray Analysis; D008875:Middle Aged; D000090063:Proto-Oncogene Mas; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology