Circulating PD-L1 is associated with T cell infiltration and predicts prognosis in patients with CRLM following hepatic resection

Does Elevated Pre-Treatment Plasma PD-L1 Level Indicate an Increased Tumor Burden and Worse Prognosis in Metastatic Colorectal Cancer?

“…As shown above, soluble PD-L1 is strongly associated with progressive disease and tumor burden, both in CRC [ 13 , 17 , 49 , 50 , 52 ] and in other malignant diseases [ 12 , 14 , 15 , 16 , 37 , 38 , 41 , 42 , 43 , 44 , 45 , 46 ]. Although there are numerous studies investigating membrane-bound PD-1/PD-L1 in various metastatic cancers [ 53 , 54 ], the soluble form has been less examined [ 55 ].…”

“…In another study [ 52 ], PD-L1 elevation had been described for progressive disease, but not for stable disease/a partial response to the treatment. Furthermore, the resection of colorectal liver metastases can also reduce PD-L1 levels, while recurrence and/or progression following hepatectomy reintroduces the increase in PD-L1 levels [ 50 ]. Although our study also contained a longitudinal analysis of various laboratory parameters, the retrospective design and the fact that the additional blood samples were taken only at baseline prevented us from analyzing PD-1/PD-L1 changes during the course of the disease.…”

“…Higher circulating PD-L1 levels have been found to be associated with a higher degree of tumor differentiation [ 49 ]. CD3 + and CD8 + T cell counts are negatively correlated with PD-L1 and PD-1 [ 50 ], and a positive association between PD-L1 and the neutrophil-to-lymphocyte ratio has been also reported [ 51 ]. Furthermore, basically all studies investigating soluble PD-L1 in CRC have reported it as a good prognostic marker [ 13 , 17 , 50 , 52 ], even for early-stage CRC [ 17 ], while soluble PD-1 seems to be independent from CRC survival to date [ 13 ].…”

Molecular Docking and Intracellular Translocation of Extracellular Vesicles for Efficient Drug Delivery

“…[ 164 , 165 , 166 , 167 , 168 , 169 , 170 , 171 , 172 , 173 , 174 , 175 , 176 , 177 , 178 ]. PD-L1 is present in exosomes released from melanoma cells [ 178 , 179 , 180 , 181 , 182 , 183 , 184 , 185 , 186 ]; however, exosomes derived from metastasised melanoma cells have a higher PD-L1 content than those derived from primary focal melanoma cells. Moreover, an electron microscope analysis revealed the PD-L1 protein was carried on the surface of the protein [ 187 ].…”

“…For example, approximately 40% of human melanoma cells express significant amounts of PD-L1 on their surfaces [ 213 ]. The presence of large amounts of exosomal PD-L1 in the blood of melanoma patients also suggests that PDL-1 has an overall effect on immunosuppression in those patients [ 161 , 162 , 182 , 186 , 214 ]. However, presently, there is no evidence that the immunity of patients with stage 4 melanoma is impaired.…”