Enrichment of Inflammatory IL-17 and TNF-α Secreting CD4(+) T Cells within Colorectal Tumors despite the Presence of Elevated CD39(+) T Regulatory Cells and Increased Expression of the Immune Checkpoint Molecule, PD-1. Breadcrumbs UL Home Research Publications Year of Publication 2016 Journal Frontiers In Oncology DOI 10.3389/fonc.2016.00050