Amplicon mapping and expression profiling identify the Fas-associated death domain gene as a new driver in the 11q13.3 amplicon in laryngeal/pharyngeal cancer.
OBJECTIVE
Amplification of the 11q13 region is a frequent event in human cancer. The highest incidence (36%) is found in head and neck squamous cell carcinomas. Recently, we reported that the amplicon size in 30 laryngeal and pharyngeal carcinomas with 11q13 amplification is determined by unique genomic structures, resulting in the amplification of a set of genes rather than a single gene.


METHODS
To investigate which gene(s) drive the 11q13 amplicon, we determined the smallest region of overlap with amplification and the expression levels of all genes within this amplicon.


RESULTS
Using array-based comparative genomic hybridization analysis, we detected a region of approximately 1.7 Mb containing 13 amplified genes in more than 25 of the 29 carcinomas. Quantitative reverse transcription-PCR revealed that overexpression of 8 potential driver genes including, cyclin D1, cortactin, and Fas-associated death domain (FADD), correlated significantly with DNA amplification. FADD protein levels correlated well with DNA amplification, implicating that FADD is also a candidate driver gene in the 11q13 amplicon. Analysis of 167 laryngeal carcinomas showed that increased expression of FADD (P = 0.007) and Ser(194) phosphorylated FADD (P = 0.011) were associated with a worse disease-specific survival. FADD was recently reported to be involved in cell cycle regulation, and cancer cells expressing high levels of the Ser(194) phosphorylated isoform of FADD proved to be more sensitive to Taxol-induced cell cycle arrest.


CONCLUSIONS
Because of the frequent amplification of the 11q13 region and concomitant overexpression of FADD in head and neck squamous cell carcinomas, we hypothesize that FADD is a marker to select patients that might benefit from Taxol-based chemoradiotherapy.
Gibcus
Johan H
JH
Department of Pathology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
Menkema
Lorian
L
Mastik
Mirjam F
MF
Hermsen
Mario A
MA
de Bock
Geertruida H
GH
van Velthuysen
Marie-Louise F
ML
Takes
Robert P
RP
Kok
Klaas
K
Alvarez Marcos
Cesar A
CA
van der Laan
Bernard F A M
BF
van den Brekel
Michiel W M
MW
Langendijk
Johannes A
JA
Kluin
Philip M
PM
van der Wal
Jacqueline E
JE
Schuuring
Ed
E
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D002277:Carcinoma / Q000235:genetics*; D002453:Cell Cycle; D002869:Chromosome Aberrations; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11; D053200:Fas-Associated Death Domain Protein / Q000235:genetics*; D020869:Gene Expression Profiling; D006801:Humans; D007822:Laryngeal Neoplasms / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D017239:Paclitaxel / Q000494:pharmacology; D010610:Pharyngeal Neoplasms / Q000235:genetics*; D010766:Phosphorylation; D013997:Time Factors
D000972:Antineoplastic Agents, Phytogenic; C505533:FADD protein, human; D053200:Fas-Associated Death Domain Protein; D017239:Paclitaxel