Abigail Boster Email: aib7@pitt.edu Lab: Khan Lab: Approximately 25 percent of the 500,000 cases of squamous cell carcinoma of the head and neck (SCCHN) that are diagnosed annually contain integrated human papillomavirus (HPV) DNA. HPVs are small, dsDNA viruses that can be divided into two classes: low risk and high risk. The low-risk HPVs are involved in persistent wart infections. On the other hand, the high-risk HPVs can integrate into the host chromosome, which disrupts regulatory genes. This results in increased expression of the viral oncogenes E6 and E7 which begins the cascade towards tumor development and cancer. MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression and have recently been shown to be associated with many types of cancers. MiRNAs are approximately 22 nt single-stranded RNA molecules that bind to the messenger RNA (mRNA) target and either inhibit their translation or promote their degradation. I plan to identify and analyze miRNAs that are differentially expressed in HPV-positive SCCHN. This will be done via miRNA microarrays of HPV-positive and HPV-negative SCCHN cell lines. Significant up- or down-regulated miRNAs will be further studied to determine function and target(s). By determining roles of miRNA in HPV-associated cancers, we can better understand the pathogenesis of viruses that cause cancer, and can thereby study more ways to prevent, treat, and/or cure the disease.