To test this hypothesis, we analyzed M1 macrophage markers, including CD80, CD32, and CD64, and M2 macrophage markers, including CD68, CD206, and CD163, in HERV-K119 env KO THP-1 cells and compared them with those in HERV-K119 env KO OVCAR3 ovarian cancer cells. Here, CD80 is linked to ovarian cancer.