Transcriptome comparison of CM versus LN mouse melanomas treated with anti-PD-1 or IgG control antibodies. CM-LN-IgG-aPD-1

Two syngeneic mouse melanoma cell lines were derived from a cutaneous metastasis (CM) or lymph node (LN) metastasis spontaneously developing in the Mt-Ret transgenic mouse melanoma model. In order to characterize their responsiveness immune checkpoint blockade, we treated syngeneic mice bearing CM or LN melanomas with monoclonal antibodies directed against PD-1 or IgG control. For molecular characterization we harvested CM and LN melanoma tissues from each treatment conditions, isolated total RNA and performed 3’mRNA-seq analysis. Consistent with higher responsiveness of CM melanoma to anti-PD-1 therapy, transcriptome analysis supported an increase of immune cell infiltration and inflammatory pathway activation in CM melanoma upon immune checkpoint blockade.