NON-PROFESSIONAL PHAGOCYTOSIS OF LEWIS LUNG CARCINOMA CELLS UNDER DIFFERENT GROWTH CONDITIONS

Phagocytosis occurs in almost all cell types of multicellular organisms. Based on their efficiency, cells are classified as professional or non-professional phagocytes, with cancer cells belonging to the latter. This property of cancer cells underlies the formation of "cell-in-cell" structures, the high frequency of which is often associated with invasion and metastasis of malignant tumors.

To investigate the ability of Lewis lung carcinoma (LLC) cells to perform non-professional phagocytosis and to analyze how this process depends on cancer cell growth conditions.

A low-metastatic variant of LLC cells (LLC/R9) was used. Phagocytic activity was examined under anchorage- dependent and anchorage-independent growth conditions, in both standard and glucose-free culture media, using fluorescent latex beads (1.0 μm in diameter).

LLC/R9 cells demonstrated phagocytic activity, which increased nearly fourfold under anchorage-independent conditions, irrespective of E-cadherin expression. Glucose deprivation reduced the percentage of bead-engulfing cells by more than twofold under both growth conditions, while increasing the number of beads internalized per cell. This indicates a pronounced heterogeneity within the cancer cell population in their sensitivity to phagocytic activation under glucose deficiency.

Non-small cell lung cancer LLC/R9 cells are capable of phagocytosis, which is markedly enhanced under anchorage-independent growth and only weakly influenced by glucose deprivation.