Monocyte chemoattractant protein-1 (MCP-1) expression in primary lymphoepithelioma-like carcinomas (LELCs) of the lung.
Lymphoepithelioma-like carcinoma (LELC) of the lung is a recently recognized primary non-small cell lung carcinoma with distinct clinicopathological features and an aetiological association with Epstein-Barr virus (EBV) infection. The tumour consists of clusters and sheets of poorly or undifferentiated tumour cells in close association with numerous mononuclear inflammatory cells, including a rich component of tumour-associated macrophages (TAMs). To investigate the molecular mechanism leading to the TAM-rich stroma, the expression of a monocyte-specific chemotactic and activating factor, monocyte chemoattractant protein-1 (MCP-1), was studied by reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization (ISH), and the presence of TAMs was demonstrated by immunohistochemistry in nine LELCs. The results were compared with those found in 17 conventional non-small cell lung carcinomas. RT-PCR showed specific MCP-1 amplification in both LELCs and non-LELCs, but ISH demonstrated a unique and extensive expression of MCP-1 transcripts by the tumour cells of LELCs only, while TAMs, stromal fibroblasts, and endothelial cells formed the major source of MCP-1 in non-LELCs. TAMs in LELCs were more abundant and showed a close topographical relationship with the MCP-1-expressing tumour cells. The results indicate that tumour cell expression of MCP-1 in LELCs is an important mechanism contributing to their distinctive morphological features. This is the first study that demonstrates the in vivo upregulation of a monocyte-specific chemokine by EBV-related carcinomas, illustrating an interesting aspect of tumour biology in EBV-related neoplasms.
Wong
M P
MP
Department of Pathology, University of Hong Kong, Queen Mary Hospital, Hong Kong.
Cheung
K N
KN
Yuen
S T
ST
Fu
K H
KH
Chan
A S
AS
Leung
S Y
SY
Chung
L P
LP
D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D018932:Chemokine CCL2 / Q000378:metabolism*; D020031:Epstein-Barr Virus Infections / Q000150:complications; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D008264:Macrophages / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018932:Chemokine CCL2; D009363:Neoplasm Proteins