摘要：BRAF inhibitors (BRAFi) selectively target oncogenic BRAF
V600E/K and are effective in 80% of advanced cutaneous malignant melanoma cases carrying the V600 mutation. However, the development of drug resistance limits their clinical efficacy. Better characterization of the underlying molecular processes is needed to further improve treatments. We previously demonstrated that transcription of
PTEN is negatively regulated by the
PTEN pseudogene antisense RNA,
PTENP1-AS, and here we investigated the impact of this transcript on clinical outcome and BRAFi resistance in melanoma. We observed that increased expression levels of
PTENP1-AS in BRAFi resistant cells associated with enrichment of EZH2 and H3K27me3 at the
PTEN promoter, consequently reducing the expression levels of
PTEN. Further, we showed that targeting of the
PTENP1-AS transcript sensitized resistant cells to BRAFi treatment and that high expression of
PTENP1-AS in stage III melanoma correlated with poor survival. Collectively, the data presented here show that
PTENP1-AS is a promising target for re-sensitizing cells to BRAFi and also a possible prognostic marker for clinical outcome in stage III melanoma.
