Fig. 4

Lung tumors induce cDC anergy through different pathways. Tumors can alter the molecular expression of DC and also upregulate the immunosuppression miRNAs in DCs to inhibit the secretion of IL-12. Exosomes secreted by lung tumor cells can induce PD-L1 expression in DCs. Furthermore, different factors (HMGB1, TSLP, lactic acid) are highly expressed in lung tumors, and these may interact with different pathways within DCs to achieve a tumor-supportive microenvironment. cDC: conventional DC; HMGB1: high mobility group box-1 protein; TSLP: thymic stromal lymphopoietin; TSLPR: thymic stromal lymphopoietin receptor; IFN-γ: interferon γ; STING: stimulator of IFN genes; TLR2: toll-like receptor 2; Treg: regulatory T cells; PD-L1: programmed cell death 1 ligand 1; IL-10R: interleukin 10 receptor; TIM3: T-cell immunoglobulin and mucin-domain 3