Fig. 1: TAMs enhanced the proliferation of colon cancer cells.

A After incubation with PMA and IL-4, the smooth surface morphology of U937 cells had a thorny appearance because of pseudopodia, and the suspended cells became adherent. B Comparison of the mRNA levels of CD68 and CD163 between U937 cells and TAMs by RT-PCR. C, D Cell growth and cell viability assays showed that co-culture with TAMs facilitated the growth and viability of HT-29 (C) and Caco-2 (D) cells in relation to the co-culture with U937 cells. E HT-29 and Caco-2 cells were cultured with 0, 25, 50, and 75% TAMs-CM or U937-CM for different time. Treatment with 50 or 75% TAMs-CM for 72 or 96 h promoted HT-29 and Caco-2 cells viability. F FACS analysis of cell cycle distribution indicated that treatment with TAMs-CM accelerated cell cycle transition from G0/G1 to S and G2/M phase. All data are presented as the mean ± SD from three independent experiments. *P < 0.05.