XJ Chen Lab Research

Key Words:Cancer; Enzymes for DNA Replication, Mutation, and Repair; APOBEC deaminases; Immune responses; Nanoparticle Assembly; Structural Biology

My research focuses on 1) Cancer biology, with emphasis on cell growth regulation through oncogenes, tumor suppressors, and DNA/RNA modifying enzymes (DNA polymerases, helicases, mutases, and repair proteins); 2) Humoral and innate immune response to viral pathogens; 3) Protein nanoparticle assembly and functions.

Cancer, immune disorder, and other human diseases can be caused by somatic mutations or/and viral infections (such as HIV, EBV, SARS-CoV-2). My laboratory studies the molecular mechanisms of the key cellular and viral proteins involved in oncogenesis and immune defenses.

Our study of cancer biology aims to understand the multiplex molecular drivers and mechanisms for cancer cell formation and development. These molecular drivers can be the dysfunctional cellular oncogenes and tumor suppressors or viral oncogenes due to infection by tumor viruses. The molecular drivers can also come from dysregulated DNA/RNA modifying enzymes (such as APOBEC mutases, DNA replication/repair enzymes), which cause continued mutations that can lead to cancer, cancer evolution, and cancer drug resistance. Our goal is to understand the underlying molecular mechanisms for these processes critical for cancer formation and evolution.

In the nanoparticle direction, we are exploring the potential application of a protein-based nanoparticle system for nucleic acid-based drug delivery. The nanoparticle, 60 nM in diameter, has a well-controlled assembly and disassembly process, and can package and deliver large genes or mRNA into cells. The goal is to genetically engineer the nanoparticle to deliver the correct gene or mRNA into a specific tissue/organ for therapy.

My laboratory uses a combination of modern research approaches, including molecular and cell biology, biochemistry and biophysics, and structural biology (X-ray and EM), in our scientific studies.