biostudies-literatureUnknown13(1)Lozzi I<h4>Background</h4>Intrahepatic cholangiocarcinoma (ICC) is a disease with poor prognosis and limited therapeutic options. We investigated the tumor immune microenvironment (TIME) to identify predictors of disease outcome and to explore targets for therapeutic modulation.<h4>Methods</h4>Liver tissue samples were collected during 2008-2019 from patients (<i>n</i> = 139) diagnosed with ICC who underwent curative intent surgery without neoadjuvant chemotherapy. Samples from the discovery cohort (<i>n</i> = 86) were immunohistochemically analyzed on tissue microarrays (TMAs) for the expression of CD68, CD3, CD4, CD8, Foxp3, PD-L1, STAT1, and p-STAT1 in tumor core and stroma areas. Results were digitally analyzed using QuPath software and correlated with clinicopathological characteristics. For validation of TIME-related biomarkers, we performed multiplex imaging mass cytometry (IMC) in a validation cohort (<i>n</i> = 53).<h4>Results</h4>CD68+ cells were the predominant immune cell type in the TIME of ICC. CD4+^high T cell density correlated with better overall survival (OS). Prediction modeling together with validation cohort confirmed relevance of CD4+ cells, PD-L1 expression by immune cells in the stroma and N-stage on overall disease outcome. In turn, IMC analyses revealed that silent CD3+CD4+ clusters inversely impacted survival. Among annotated immune cell clusters, PD-L1 was most relevantly expressed by CD4+FoxP3+ cells. A subset of tumors with high density of immune cells ("hot" cluster) correlated with PD-L1 expression and could identify a group of candidates for immune checkpoint inhibition (ICI). Ultimately, higher levels of STAT1 expression were associated with higher lymphocyte infiltration and PD-L1 expression.<h4>Conclusions</h4>These results highlight the importance of CD4+ T cells in immune response against ICC. Secondly, a subset of tumors with "hot" TIME represents potential candidates for ICI, while stimulation of STAT1 pathway could be a potential target to turn "cold" into "hot" TIME in ICC.Oncoimmunology2406052https://www.ebi.ac.uk/biostudies/studies/S-EPMC11445892biostudies-literatureClinical prognosticators and targets in the immune microenvironment of intrahepatic cholangiocarcinoma.PMC11445892Reutzel-Selke ABarone MFeldbrugge LModest DPFelsenstein MKrenzien FSchoning WJohnson JCSinn BVPratschke JSchirmeier AMalinka TWang RHu MSauer IMGebert PLozzi IArnold AEschrich JfalseClinical prognosticators and targets in the immune microenvironment of intrahepatic cholangiocarcinoma.<h4>Background</h4>Intrahepatic cholangiocarcinoma (ICC) is a disease with poor prognosis and limited therapeutic options. We investigated the tumor immune microenvironment (TIME) to identify predictors of disease outcome and to explore targets for therapeutic modulation.<h4>Methods</h4>Liver tissue samples were collected during 2008-2019 from patients (<i>n</i> = 139) diagnosed with ICC who underwent curative intent surgery without neoadjuvant chemotherapy. Samples from the discovery cohort (<i>n</i> = 86) were immunohistochemically analyzed on tissue microarrays (TMAs) for the expression of CD68, CD3, CD4, CD8, Foxp3, PD-L1, STAT1, and p-STAT1 in tumor core and stroma areas. Results were digitally analyzed using QuPath software and correlated with clinicopathological characteristics. For validation of TIME-related biomarkers, we performed multiplex imaging mass cytometry (IMC) in a validation cohort (<i>n</i> = 53).<h4>Results</h4>CD68+ cells were the predominant immune cell type in the TIME of ICC. CD4+^high T cell density correlated with better overall survival (OS). Prediction modeling together with validation cohort confirmed relevance of CD4+ cells, PD-L1 expression by immune cells in the stroma and N-stage on overall disease outcome. In turn, IMC analyses revealed that silent CD3+CD4+ clusters inversely impacted survival. Among annotated immune cell clusters, PD-L1 was most relevantly expressed by CD4+FoxP3+ cells. A subset of tumors with high density of immune cells ("hot" cluster) correlated with PD-L1 expression and could identify a group of candidates for immune checkpoint inhibition (ICI). Ultimately, higher levels of STAT1 expression were associated with higher lymphocyte infiltration and PD-L1 expression.<h4>Conclusions</h4>These results highlight the importance of CD4+ T cells in immune response against ICC. Secondly, a subset of tumors with "hot" TIME represents potential candidates for ICI, while stimulation of STAT1 pathway could be a potential target to turn "cold" into "hot" TIME in ICC.2024-01-01T00:00:00Z20242025-04-04T01:59:37.092Z2025-04-04T01:59:37.092ZS-EPMC114458923935938910.1080/2162402X.2024.2406052