Presentation description

Although only representing ~5% of non-Hodgkin lymphoma (NHL) cases, Mantle Cell Lymphoma (MCL) is an aggressive form of cancer. MCL cases have recorded one of the highest lymphoma-specific mortality rates, with only a 50% 5-year survival outcome. Amongst these cases, recent studies have found that approximately 18% of MCL patients were discovered to have allelic mutations in the ubiquitin protein ligase E3 component n-recognin 5 (UBR5). UBR5 is an E3 ubiquitin ligase, an enzyme that attaches ubiquitin molecules to proteins to tag them for proteasomal degradation. Our studies found that mutations in UBR5 led to stabilization and overexpression of UBR5. Mass spectrometry approaches also identified interaction and overexpression of U5 spliceosome components, including Pre-mRNA Processing Factor 8 (PRPF8). PRPF8 is a component of the spliceosome that aids in pre-mRNA splicing. Proper splicing requires maintaining the correct balance of PRPF8, and a disruption in this interaction may affect spliceosome efficiency. We hypothesize that PRPF8 and UBR5 promote MCL progression.
This is the foundation on which my research begins, altering the expression of PRPF8 to observe alterations in UBR5 and cellular effectiveness. Through lentiviral transduction, we can silence PRPF8 with shRNAs to observe their effect on cellular proliferation and apoptosis. We utilized HEK293T cells, originally from a human embryonic kidney, and Jeko-1 cells, derived from a relapsed MCL patient. HEK293T cells were transfected to generate shPRPF8 viral particles using specialized packaging and envelope plasmids. Both Jeko-1 and HEK293T cells were later transduced with the virus, allowing for the analysis of the effects of PRPF8 knockdown in comparison to UBR5 expression and overall cellular function of each cell line. These preliminary studies suggest that PRPF8 plays a role in cell proliferation and survival.