Abstract
Purpose Conjunctival squamous cell carcinoma (cSCC) represent some of the most frequently encountered ocular surface neoplasms worldwide, and are particularly prevalent in Saudi Arabia. Our aim in this study is to uncover novel diagnostic biomarkers, as well as molecular pathways which can be targeted using new therapies. Methods We analyzed DNA extracted from 14 snap frozen cSCC tumor specimens resected at KKESH using Agilent 180K high density oligonucleotide arrays, with 12 samples giving high quality hybridizations. We are now confirming increased gene dosage using the Nanostring platform and investigating mRNA expression at the8p11.22 loci with quantitative PCR. Results Of these 12, the number of clear regions of DNA loss ranged from 1 to 24 per tumor, while gains (including potential amplifications) ranged from 2 to 14 per tumor. Recurring aberrations were observed in chromosome 6, where the region 6p22.1-p21.32 was lost in 4 out of 12 specimens (33%), in chromosome 14, where the locus 14q13.2 was lost in 5 of the 12 samples (42%), and in chromosome 22, where 5 samples showed DNA loss and one DNA gain at 22q11.22. However the most frequent alteration was observed in chromosome 8, where the locus 8p11.22 was amplified in 9 tumors (75%) and lost in the other 3 samples (25%). Conclusion We observed the most profound DNA alterations in the region of 8p11.22 which contains part or all of the ADAM1B, ADAM3A, and ADAM5p genes. It is also very near to the ADAM9 locus, which was recently found to be commonly amplified in oral squamous cell carcinoma (Plos One 2013,8:e54705). [PUBLICATION ABSTRACT]