The expression rates of CD31 in tumor tissues of the lipiodol alone group, lipiodol + DOX group, and lipiodol + TRRP@DOX group 7 days postoperatively were 2.33 ± 0.40%, 9.46 ± 1.22%, 5.76 ± 0.45%, and 1.53 ± 0.25%, respectively, indicating that TRRP@DOX + lipiodol group had lower tumor microvessel density compared to the lipiodol group (P < 0.0001) and the lipiodol + DOX group (P < 0.001). The gene discussed is PECAM1; the disease is neoplasm.