https://www.selleckchem.com/products/ndi-091143.html BRAF inhibitors (BRAFi) have shown remarkable clinical efficacy in the treatment of melanoma with BRAF mutation. Nevertheless, most patients end up with the development of BRAFi resistance, which strongly limits the clinical application of these agents. POU4F1 is a stem cell-associated transcriptional factor that is highly expressed in melanoma cells and contributes to BRAF-activated malignant transformation. However, whether POU4F1 contributes to the resistance of melanoma to BRAFi remains poorly understood. Here, we report that over-expressed POU4F1 contributed to the acquired resistance of melanoma cells to Vemurafenib. Furthermore, POU4F1 promoted the activation of ERK signaling pathway via transcriptional regulation on MEK expression. In addition, POU4F1 could increase the expression of MITF to retain the resistance of melanoma cells to BRAFi. Collectively, our findings reveal that POU4F1 re-activates the MAPK pathway by transcriptional regulation on MEK expression and promotes MITF expression, which ultimately results in the resistance to BRAFi in melanoma. Our study supports that POU4F1 is a potential combined therapeutic target with BRAFi therapy for melanoma.Cytosolic DNA is an indicator of pathogen invasion or DNA damage. The cytosolic DNA sensor cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) synthase (cGAS) detects DNA and then mediates downstream immune responses through the molecule stimulator of interferon genes (STING, also known as MITA, MPYS, ERIS and TMEM173). Recent studies focusing on the roles of the cGAS-STING pathway in evolutionary distant species have partly sketched how the mammalian cGAS-STING pathways are shaped and have revealed its evolutionarily conserved mechanism in combating pathogens. Both this pathway and pathogens have developed sophisticated strategies to counteract each other for their survival. Here, we summarise current knowledge on the interactions between