| First Author | Landsberg J | Year | 2012 |
| Journal | Nature | Volume | 490 |
| Issue | 7420 | Pages | 412-6 |
| PubMed ID | 23051752 | Mgi Jnum | J:189221 |
| Mgi Id | MGI:5444770 | Doi | 10.1038/nature11538 |
| Citation | Landsberg J, et al. (2012) Melanomas resist T-cell therapy through inflammation-induced reversible dedifferentiation. Nature 490(7420):412-6 |
| abstractText | Adoptive cell transfer therapies (ACTs) with cytotoxic T cells that target melanocytic antigens can achieve remissions in patients with metastatic melanomas, but tumours frequently relapse. Hypotheses explaining the acquired resistance to ACTs include the selection of antigen-deficient tumour cell variants and the induction of T-cell tolerance. However, the lack of appropriate experimental melanoma models has so far impeded clear insights into the underlying mechanisms. Here we establish an effective ACT protocol in a genetically engineered mouse melanoma model that recapitulates tumour regression, remission and relapse as seen in patients. We report the unexpected observation that melanomas acquire ACT resistance through an inflammation-induced reversible loss of melanocytic antigens. In serial transplantation experiments, melanoma cells switch between a differentiated and a dedifferentiated phenotype in response to T-cell-driven inflammatory stimuli. We identified the proinflammatory cytokine tumour necrosis factor (TNF)-alpha as a crucial factor that directly caused reversible dedifferentiation of mouse and human melanoma cells. Tumour cells exposed to TNF-alpha were poorly recognized by T cells specific for melanocytic antigens, whereas recognition by T cells specific for non-melanocytic antigens was unaffected or even increased. Our results demonstrate that the phenotypic plasticity of melanoma cells in an inflammatory microenvironment contributes to tumour relapse after initially successful T-cell immunotherapy. On the basis of our work, we propose that future ACT protocols should simultaneously target melanocytic and non-melanocytic antigens to ensure broad recognition of both differentiated and dedifferentiated melanoma cells, and include strategies to sustain T-cell effector functions by blocking immune-inhibitory mechanisms in the tumour microenvironment. |
