The HBV-X gene product promotes the upregulation of epidermal growth factor receptor (EGFR) expression, which results in the malignant monoclonal proliferation of lymphocytes and ultimately leads to the development of malignant lymphoma through the binding site for nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) on B-lymphoma cells and human T-cell leukemia cells [18,19]. Here, EGFR is linked to T-cell leukemia.