It is known that PD-L1 and PD-1 interaction leads to immune suppression which may partially be responsible for the immune resistance of tumor cells, but high PD-L1 expression may also promote immune responses through PD-L1's binding to unknown receptors other than PD-1, resulting in T-cell proliferation and secretion of certain cytokines such as IL-10 and interferon γ [4, 29], which in turn activate strong antitumor effects. Here, IL10 is linked to neoplasm.