Comparison of LANA1 and LANA2 expression in Kaposi's sarcoma (KS), Castleman's disease (CD) and primary effusion lymphoma (PEL) tissues. Note that LANA1 is expressed in all KSHV-infected tissues but LANA2 has an expression pattern restricted to hematopoietic tissues. Figre 4. vIRF-1 (ORFK9) expression in BCBL1 tissue culture cells. vIRF-1 shuttles between the cytoplasm and the nucleus as shown in these two cells. Although vIRF-1 is readily seen in PEL tissue culture cell lines, it is rarely expressed in PEL tumors. It is expressed in Castleman's disease tumors.