Amy Gardiner Email: asg18@pitt.edu Lab: Khan Lab My project concerns the role of microRNAs in human papillomavirus (HPV)- associated cancers. Human papillomaviruses are common papilloma (wart)-causing viruses. They are responsible for inducing a variety of cutaneous and mucosal lesions and importantly are the cause of cervical and a subset of oropharyngeal cancers. Cervical cancer is the second-highest cancer-related cause of death among women worldwide. Although a vaccine has been approved by the FDA, cervical cancer remains a threat for the millions of women currently infected with genital HPVs. The majority of HPV-associated carcinomas harbor integrated virus, with increased expression of the viral oncogenes E6 and E7. The viral proteins interact with a number of cellular proteins, enhancing cellular proliferation through deregulation of cell cycle control mechanisms. A novel class of gene regulators called microRNAs (miRNAs) has recently been linked to many cancers and may play a role in progression to cancer. MiRNAs are 22nt non-protein-coding RNAs that most commonly function as negative post-transcriptional gene regulators. MiRNAs hybridize to target messenger RNAs (mRNAs) and mediate translational repression or mRNA cleavage/destruction. MiRNA targets include genes involved in development, cell growth, and cell proliferation. Also, viruses involved in carcinogenesis have been found to encode miRNAs. The long term goals of this project are to gain a better understanding of the interaction between HPV-16, which causes the majority of cervical cancers, and the cell during carcinogenesis and to identify diagnostic and therapeutic targets based on our miRNA studies. Specifically, we aim to determine how HPV-16 affects the expression of cellular miRNAs. MiRNA microarray studies were performed in which differential expression of miRNAs was found between HPV-16 positive and HPV-16 negative cells. These data were validated by Northern blotting and qRT-PCR analyses. Transfection and siRNA studies showed that microRNA-218 was specifically reduced by HPV-16 E6. Additional expression and protein analyses will be performed in order to characterize the role of HPV-16 E6 in the regulation of this miRNA and its targets. We will also identify potential HPV-16 miRNAs and their targets. Computational analysis with the RNA-folding software mFold suggests that HPV-16 may encode miRNAs. A custom microarray has been designed for this purpose. An understanding of how HPV-16 regulates viral and cellular gene expression is paramount to developing new treatments. This study will help identify new diagnostic and therapeutic targets for combating HPV infection and HPV-associated human cancers.