Non-coding RNA molecules such as microRNAs (miRNAs) may play an important role 
in human carcinogenesis. Their expression has been profiled in many human 
cancers but there are few published studies in head and neck cancer. In this 
study, the relative expression of 261 mature miRNA genes was determined in nine 
head and neck cancer cell lines using an oligonucleotide array platform. 
Thirty-three miRNAs in the array were found to be highly expressed and 22 showed 
low levels of expression in all cell lines. Notable was the high expression of 
miR-21 and miR-205. Expression of several miRNAs was validated using Northern 
blot analysis. Potential targets of validated miRNAs included tumor suppressor 
genes, kinesin family member 1B isoform alpha (KIF1B), and hypermethylated in 
cancer 2 (HIC2), and pleomorphic adenoma gene 1 (PLAG1). This study provides the 
largest genomewide survey of mature miRNA transcripts in head and neck cancer 
cell lines.