Supporting data for "CX3CL1 recruits CX3CR1pos macrophages to promote tumor progression in intrahepatic cholangiocarcinoma"

<p>  </p> <p>Intrahepatic cholangiocarcinoma (iCCA) is the second most prevalent liver malignancy with a worse prognosis. It is characterized by a highly desmoplastic tumor microenvironment (TME) featured with abundant macrophages. Chemokines orchestrate the recruitment and infiltration of macrophages into the TME. The significance of CX3CR1^pos macrophages with pro-tumoral features has been documented in several tumors other than iCCA. We aimed to investigate the role of the CX3CL1/CX3CR1 signaling in the progression of iCCA.</p> <p><br></p> <p>The data are related to the following contents. CX3CL1 expression was analyzed in two independent clinical cohorts (HKU and external cohorts). The clinical significances of CX3CL1 and CX3CR1^pos macrophages were evaluated by Cox proportional hazards model. Phenotypes and functions of tumor-infiltrated and monocyte-derived CX3CR1^pos and CX3CR1^neg macrophages were also assessed via mRNA sequencing and flow cytometry. The interactions between iCCA cells and CX3CR1^pos macrophages were evaluated both <em>in vitro</em> and <em>in vivo</em>. The mechanisms for CX3CR1^pos macrophages contribute to the immunosuppressive microenvironment and tumor invasiveness were investigated in cells and an orthotopic model. The therapeutic potential of a CX3CR1 antagonist (AZD8797) targeting the CX3CL1-CX3CR1 axis was explored <em>in vivo</em>. </p> <p><br></p> <p>Our data revealed that CX3CL1 was the most frequently up-regulated chemokine of iCCA in HKU and TCGA cohorts. Overexpression of CX3CL1 in iCCA tissue indicated tumor invasiveness and poor prognosis in both HKU and external validation cohorts. CX3CR1^pos macrophages were independent risk factors for both disease-free and overall survival of iCCA. CX3CL1 facilitated the infiltration of CX3CR1^pos macrophages into the TME of iCCA. CX3CR1^pos macrophages not only contributed to immunosuppressive TME through secreting IL10, but also promoted an invasive phenotype of iCCA cells via CCL5-mediated epithelial-mesenchymal transition. It is demonstrated that the tumor volume of CX3CL1-high-expressing xenografts was markedly more extensive than those of CX3CL1-low-expressing xenografts. Higher rate of lung metastases was shown in the group with CX3CL1-high-expressing xenografts compared to the control group. The protumoral effects of CX3CL1 cannot be achieved without the presence of CX3CR1^pos macrophages. Notably, blockage of the CX3CL1/CX3CR1 axis using AZD8797 inhibited the growth and metastasis of iCCA <em>in vivo</em> through the attenuation of immunosuppressive environment.</p>