Related Experiment Video
Updated: Feb 27, 2026

DNA-barcode-based Multiplex Immunofluorescence Imaging to Analyze FFPE Specimens from Genetically Reprogrammed Murine Melanoma
Published on: June 6, 2025
Parallel profiling of immune infiltrate subsets in uveal melanoma versus cutaneous melanoma unveils similarities and
Yong Qin1, Mariana Petaccia de Macedo2, Alexandre Reuben3
1Department of Melanoma Medical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX, USA.
Abstract:
The low response rates to immunotherapy in uveal melanoma (UM) sharply contrast with reputable response rates in cutaneous melanoma (CM) patients. To characterize the mechanisms responsible for resistance to immunotherapy in UM, we performed immune profiling in tumors from 10 metastatic UM patients and 10 metastatic CM patients by immunohistochemistry (IHC). Although there is no difference in infiltrating CD8+ T cells between UM and CM, a significant decrease in programmed death-1 (PD-1)-positive lymphocytes was observed and lower levels of programmed death ligand-1 (PD-L1) in UM metastases compared with CM metastases. Tumors from metastatic UM patients showed a lower success rate of tumor-infiltrating lymphocyte (TIL) growth compared with metastatic CM (45% vs. 64% success), with a significantly lower quantity of UM TIL expanded overall. These studies suggest that UM and CM are immunologically distinct, and provide potential explanation for the impaired success of immunotherapy in UM.

