IMMUNOLOGY2026™ Conference Recordings For Attendees-Deletion of RIAM in myeloid cells accelerates tumor growth by macrophage reprogramming

Deletion of RIAM in myeloid cells accelerates tumor growth by macrophage reprogramming

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Video Summary

The presenter studied RIAM’s role in myeloid cells within the tumor microenvironment using conditional RIAM knockout mice and two tumor models, B16 melanoma and MC17 fibrosarcoma. RIAM deletion caused larger, heavier tumors and enlarged spleens. MDSCs from knockout mice were less suppressive of T-cell proliferation, but tumor-associated macrophages shifted toward a more M2-like, tumor-promoting phenotype, with increased M2 markers and reduced activation/presentation markers. RNA-seq confirmed pathways linked to M2 functions were upregulated, while inflammatory and antigen-presentation pathways were downregulated. Overall, RIAM loss appears to accelerate tumor growth mainly by reprogramming macrophages.

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Date April 18, 2026 8:00 AM - 8:15 AM

Room 156

Session Tumor and Immune Cell Crosstalk

Speaker Anthos Christofides

Track Tumor Immunology: Cellular Responses and Tumor Microenvironment (TIME)

Year 2026

Keywords

RIAM

myeloid cells

tumor microenvironment

M2 macrophages

tumor growth

April 18, 2026 8:00 AM - 8:15 AM

156

Tumor and Immune Cell Crosstalk

Anthos Christofides

Tumor Immunology: Cellular Responses and Tumor Microenvironment (TIME)

2026