Identification of Monocyte Chemotactic Activity Produced by Malignant Cells

TLDR

Human malignant cells secrete low‑molecular‑weight proteins that attract peripheral blood monocytes, a phenomenon also observed in vascular smooth muscle cells. Tumor cells produce a single class of monocyte‑chemoattractant proteins similar to smooth‑muscle‑cell factors, indicating a common recruitment mechanism that may influence tumor growth.

Abstract

Human malignant cells secrete low molecular size proteins that attract peripheral blood monocytes and may be responsible for the accumulation of tumor-associated macrophages observed in vivo. Similar chemotactic proteins are secreted by cultured vascular smooth muscle cells. The predominant monocyte chemoattractants produced by tumor cells of differing origin were demonstrated to be related to smooth muscle cell-derived chemotactic factor. Thus, a single class of chemotactic proteins is produced by different cell types, which suggests a common mechanism for the recruitment of monocytes and macrophages. These results are significant in view of the potential of macrophages to affect tumor growth.