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The tumor suppressor gene, Fry, induces reversal of epithelial-mesenchymal transition (EMT) phenotype in the breast cancer cell line MDA-MB-231. Based on in silico predictions made by Ingenuity Pathway AnalysisTM (IPA), we hypothesized that FRY and microRNAs interact and these interactions link FRY to EMT. In this study we attempted to identify microRNAs that are differentially expressed in breast cancer cells without (MDA-MB-231) and with (231wCFry) ectopic Fry expression. Using TaqMan MicroRNA Array Cards to screen of over 700 microRNAs, we identified 118 microRNAs that were differentially expressed between cells with and without Fry expression. Among the differentially expressed microRNAs, hsa-mir-25, hsa-mir-106b, and hsa-mir-203 were previously associated with EMT. We used IPA to build interaction networks between microRNAs, FRY, and two genes (CACNAID, and NDR1), whose expression levels were tightly correlated with the expression of FRY. This in silico approach suggested that hsa-mir-515 may play a role. However, our results indicated that the expression of has-mir-515 was not significantly changed by ectopic expression of Fry expression in MDA-MB-231 cells. We next chose to investigate hsa-mir-301b, whose expression was known to be increased in certain cancers. Our results showed hsa-mir-301b expression is decreased 100-fold in MCF-10A and 231wCFry as compared the to the MDA-MB-231 cell line. This correlation suggested that hsa-mir-301b could play a role in tumorigencity of breast cancer, and ectopic expression of Fry may contribute to decreased hsa-mir-301b expression. The microRNA hsa-mir-4728-3p was found to share 83% alignment complementarity to the mRNA nucleotide region 4,561-4,583 of Fry. Expression of hsa-mir-4728-3p was decreased 100-fold in 231wCFry and increased in 2.5-fold in MCF-10A compared to MDA-MB-231 cells. These findings were unexpected given previous studies demonstrating a direct relationship between transcription of hsa-mir-4728-3p and ERRB2. Given that these cell lines do not express ERRB2 the observed increased expression of mir-4728-3p in MCF-10 cells and decrease in expression in 231wCFry compared to MDA-MB-231 was unexpected. The studies described in this thesis indicated ectopic expression of the Fry tumor suppressor gene in the triple negative MDA-MB-231 breast cancer cell line correlates with the expression of numerous microRNAs, including many previously linked to EMT and carcinogenesis.