Research Papers:

ABSTRACT

The protein-acyltransferase DHHC3 supports a few different tumor malignancies, but mechanisms have been unclear. Here we report that DHHC3-null B16F10 melanoma cells showed markedly elevated oxidative stress and senescence, accompanied by diminished tumor growth within immunocompetent C57/BL6 mice, but not in immunodeficient NOD-SCID mice. These results suggest that absence of DHHC3 enhances innate and/or adaptive anti-melanoma immunity. Consistent with this, DHHC3-null melanomas contained elevated numbers of anti-tumor cells (M1 macrophages, NK, CD4⁺T, CD8⁺T), whereas pro-tumor cells (M2 macrophages, MDSCs) were diminished. Unexpectedly, DHHC3 ablation minimally affected experimental metastasis of cells injected into either immunocompetent C57/BL6 or immunodeficient NOD-SCID mice. We conclude that DHHC3 ablation does not fundamentally alter melanoma cell growth and invasion/metastasis (independent of the immune system) despite its effects on oxidative stress and senescence. However, DHHC3 does control primary melanoma growth by supporting anti-melanoma immunity.