Figure 6. The therapeutic effects of the mono-, dual and triple combination therapy on two models of colorectal carcinomatosis.
(A). Treatment of human colorectal cancer HCT116 carcinomatosis in nude mice. Athymic nude mice (n=10 mice/group) were injected intraperitoneally (i.p.) with 1 × 107 HCT116 cells. Twelve (12) days after tumor cell injection, the mice were treated with i.p. administration of Ox [2.5 mg/Kg], vJS6 [1.0 × 106 pfu], vvTRAIL [1.0 × 106 pfu], or combinations of Ox with either of the viruses. Viruses were injected on day 12 and Ox was administered on days 13, 15, 17, and 19. Ox in combination with either vJS6 (p < 0.045) or vvTRAIL (p < 0.0025) resulted in significantly longer survival compared to controls. Combination treatment with Ox and vvTRAIL achieved significantly longer survival than treatment with vvTRAIL alone (p < 0.0075) or treatment with the combination of vJS6 and Ox (p < 0.0001). (B). Treatment of MC38 syngeneic murine colorectal carcinomatosis in C57BL/6 mice. C57BL/6 mice were injected intraperitoneally (i.p.) with 2 × 105 MC38 cells, followed on day 7 by i.p. administration of Ox, vJS6 [3.0 × 106 pfu], vvTRAIL [3.0 × 106 pfu] or combinations. Viruses were injected on day 7 and Ox was administered on days 9, 11, 13, and 15. Combination treatment with vvTRAIL and Ox (p < 0.0075 vs. control) resulted in survival advantages significantly better than with Ox (p < 0.019), vJS6 (p < 0.031), or vvTRAIL (p < 0.01) alone. Comparison of vvTRAIL and Ox treatment to the combination of Ox and vJS6 did not reveal a significant survival advantage (p < 0.093).