Icariin regulates tumor immune microenvironment
Because of efficient inhibitory effect of icariin on NF-κB signaling
pathway, we hypothesized that icariin probably has ability of
attenuating tumor immunosuppressive microenvironment. MDSCs which are
usually accumulated in tumors are responsible for tumor
immunosuppressive microenvironment(Inigo-Marco & Alonso, 2019; Wu, Tan,
Hu, Zhou, Yan & Ding, 2019). So, we firstly detected the changes of
tumor infiltrated CD4+ and CD8+ T
cells after treatment with icariin. As shown in Figure 6M, proportion of
tumor infiltrated CD4+ and CD8+ T
cells were significantly increased after treatment with icariin.
Additionally, icariin dramatically downregulated proportion of MDSCs in
tumors in comparison with control group (Fig. 6N). Collaboratively,
icariin could relieve tumor immunosuppressive microenvironment, thus
enhancing antitumor effect.