Human herpesvirus-8 genes are expressed in pulmonary inflammatory myofibroblastic tumor (inflammatory pseudotumor)

Am J Surg Pathol. 2001 May;25(5):624-9. doi: 10.1097/00000478-200105000-00009.

Abstract

The presence of human herpesvirus-8 DNA sequences, as well as an overexpression of human interleukin-6 and human cyclin D1 in myofibroblastic cells of inflammatory myofibroblastic tumor (inflammatory pseudotumor), has recently been reported. We describe the pattern of human herpesvirus-8 gene expression in five cases of pulmonary inflammatory myofibroblastic tumor. Reverse transcriptase-polymerase chain reaction (RT-PCR), with several positive and negative controls, was performed to detect mRNA of 11 open reading frames encoded by human herpesvirus-8 in lytic and latent stages of viral replicative cycle. We found molecular transcripts from ORF16, ORFK13, and ORF72 in the five cases and from ORFK2 in four of five neoplasms. The corresponding encoded proteins were human homologous oncoproteins (viral cyclin-D), inflammatory cytokines (viral IL-6), and inhibitors of apoptotic pathways (viral FLIP and viral Bcl-2), mostly expressed in a latent viral replicative stage. The rest of open reading frames examined included mainly lytic-associated genes and showed no expression. The spectrum of expressed viral genes is not the same as can be observed in Kaposi's sarcoma or multicentric Castleman's disease, suggesting that human herpesvirus-8 plays a different role in the pathogenesis of its associated diseases. These differences may be related to either cell-specific or immunologic host factors.

MeSH terms

  • Activin Receptors
  • Adult
  • Aged
  • CASP8 and FADD-Like Apoptosis Regulating Protein
  • Carrier Proteins / metabolism
  • Cyclin D
  • Cyclins / metabolism
  • DNA Primers / chemistry
  • DNA, Viral / genetics
  • Female
  • Gene Expression
  • Genes, Viral / genetics*
  • Granuloma, Plasma Cell / pathology
  • Granuloma, Plasma Cell / surgery
  • Granuloma, Plasma Cell / virology*
  • Herpesvirus 8, Human / genetics*
  • Herpesvirus 8, Human / isolation & purification
  • Herpesvirus 8, Human / metabolism
  • Humans
  • Interleukin-6 / metabolism
  • Intracellular Signaling Peptides and Proteins*
  • Lung Neoplasms / pathology
  • Lung Neoplasms / surgery
  • Lung Neoplasms / virology*
  • Male
  • Middle Aged
  • Open Reading Frames / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • RNA, Messenger / analysis
  • Reverse Transcriptase Polymerase Chain Reaction
  • Viral Proteins / genetics
  • Viral Proteins / metabolism

Substances

  • CASP8 and FADD-Like Apoptosis Regulating Protein
  • CFLAR protein, human
  • Carrier Proteins
  • Cyclin D
  • Cyclins
  • DNA Primers
  • DNA, Viral
  • Interleukin-6
  • Intracellular Signaling Peptides and Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • RNA, Messenger
  • Viral Proteins
  • Protein Serine-Threonine Kinases
  • Activin Receptors