Our research team studies genetic elements that lead to the development and progression of cancer. One of these genes, called Pax-5, normally controls cellular activity and growth of healthy cells. However, deregulated levels of Pax-5 products also lead to cell hyperactivity and cancer. Recently, we have identified a new class of products, which derive from the Pax-5 gene; called circular RNAs (circRNAs). Studies on circRNAs show that they usually bind and inhibit important regulators (ex: microRNAs) of cell hyperactivity and homeostasis. Our preliminary findings show that circRNA levels of the Pax-5 gene are 20 times higher in cancer patients in comparison to healthy individuals. Consequently, elevated levels of Pax-5 circRNAs bind and inhibit microRNAs, which are required to inhibit cancer behaviour. The aim of this study is to characterize the specific microRNAs regulated by Pax-5 circRNAs in blood cancer. The knowledge gained from this study is important to understand the regulators of blood cancer and to develop better anticancer strategies.