Circulating CD14(+) CD16(+) monocyte levels predict tissue invasive character of cholangiocarcinoma

Abstract

Chronic inflammation as a risk factor for cancer development is driven in part by monocyte/macrophages, which in many cancers exhibit pro-tumorigenic activity. In this study we identified elevation in CD14(+) CD16(+) , a minor blood monocyte subpopulation in cholangiocarcinoma (CCA) patients, compared to normal and biliary disease patient specimens. Tumour association was suggested by the observation that this elevated level decreased to normal after tumour resection. Moreover, the elevated level of CD14(+) CD16(+) monocytes in CCA patient blood correlated with degree of MAC387-positive (recent blood-derived macrophage migrant-specific marker) tumour-associated macrophage infiltration as determined by immunohistochemistry. These CD14(+) CD16(+) monocytes were suggested to enhance tumour progression as this subpopulation possesses (i) high expression of adhesion molecules (CD11c, CD49d, and CD54) and scavenger receptor (CD163), which enable them to adhere strongly to endothelial cells, and (ii) that peripheral blood monocytes from CCA patients express high levels of growth and angiogenic factor-related genes (epiregulin, VEGF-A and CXCL3). Elevation of peripheral CD14(+) CD16(+) monocyte levels was associated with features associated with poor prognosis CCA parameters (non-papillary type and high number of tissue macrophages). These data indicate that the CD14(+) CD16(+) monocytes from CCA patients with pro-tumorigenic characteristics may associate with rapid tumour progression and poor patient outcome. If confirmed in subsequent studies, the level of CD14(+) CD16(+) monocytes may serve as a marker for disease activity in CCA patients and serve as a target for pathogenic macrophage specific drug development.

© 2010 British Society for Immunology.

Figures

Fig. 1

Expression levels of EREG, VEGFA, CXCL3 and CXCL10 of peripheral blood monocytes from cholangiocarcinoma (CCA) patients in comparison with those from healthy subjects. Monocytes from CCA patients expressed significantly higher levels of EREG and CXCL3 and lower levels of CXCL10 than those from healthy subjects. *P < 0·05; Student's t-test.

Fig. 2

The association of CD14+CD16+ monocytes from cholangiocarcinoma (CCA) subjects and expression levels of pro-tumoringenic genes. (a) Amount of CD14+CD16+ cells in peripheral blood of CCA patients compared with healthy controls (P = 0·25). The data present as mean ± standard deviation. (b–d) The association between CD14+CD16+ monocyte subpopulation and the expression levels of EREG (P = 0·41), CXCL3 (P < 0·03) and CXCL10 (P = 0·88).

Fig. 3

Two-colour flow-cytometric analysis of circulating monocyte subpopulations in whole blood. Monocytes were gated according to their forward- and side-scatter characteristics. The expansions of CD14+CD16+ monocytes in peripheral blood of cholangiocarcinoma (CCA) patients, benign biliary disease patients (BBD) and healthy subjects were compared based on the numbers of CD14+CD16+ monocytes in percentage value (a) and absolute number (b). The expansions of CD14+CD16+ monocytes in peripheral blood of CCA patients between pre- and post-operations (n = 6) were compared based on the numbers of CD14+CD16+ monocytes in percentage value (c) and absolute number (d). *P < 0·05; **P < 0·001.

Fig. 4

(a) The distribution and density of tissue MAC387 positive cells in tumour tissue. Immunostaining of MAC387-positive cells at leading edge of invasive tumour and perivascular areas (×40 HP); (b) The Kaplan–Meier survival curves of cholangiocarcinoma (CCA) patients who had high or low levels of CD14+CD16+ monocytes (median: 257 days and 365 days, respectively).