Background: As the selective inhibitor of BRAF kinase, vemurafenib exhibits effective antitumor activities in patients with V600 BRAF mutant melanomas. However, acquired drug resistance invariably develops after its initial treatment. Methods: Immunohistochemical staining was performed to detect the expression of iNOS and hTERT, p-p65, Epcam, CD44, PCNA in mice with melanoma xenografts. The proliferation and migration of melanoma cells were detected by MTT, tumorsphere culture, cell cycle, cell apoptosis, AO/EB assay and colony formation, transwell assay and scratch assay in vitro, and tumor growth differences were observed in xenograft nude mice. Changes in the expression of key molecules in the iNOS/hTERT signaling pathways were detected by western blot. Nucleus-cytoplasm separation, and immunofluorescence analyses were conducted to explore the location of p50/p65 in melanoma cell lines. Flow cytometry assay were performed to determine the expression of CD44. Pull down assay and ChIP assay were performed to detect the binding ability of p65 at iNOS and hTERT promoters. Additionally, hTERT promoter-driven luciferase plasmids were transfected in to melanoma cells with indicated treatment to determine luciferase activity of hTERT. Results: Melatonin significantly and synergistically enhanced vemurafenib-mediated inhibitions of proliferation, colony formation, migration and invasion and promoted vemurafenib-induced apoptosis, cell cycle arresting and stemness weakening in melanoma cells. Further mechanism study revealed that melatonin enhanced the antitumor effect of vemurafenib by abrogating nucleus translocation of NF-κB p50/p65 and their binding at iNOS and hTERT promoters, thereby suppressing the expression of iNOS and hTERT. The elevated anti-tumor capacity of vemurafenib upon co-treatment with melatonin was also evaluated and confirmed in mice with melanoma xenografts. Conclusions: Collectively, our results demonstrate melatonin synergizes the antitumor effect of vemurafenib in human melanoma by inhibiting cell proliferation and cancer-stem cell traits via targeting NF-κB/iNOS/hTERT signaling pathway, and suggest the potential of melatonin in antagonizing the toxicity of vemurafenib and augmenting its sensitivities in melanoma treatment.
Background: Activation of pericytes leads to renal interstitial fibrosis, but the regulatory mechanism of pericytes in the progression from AKI to CKD remains poorly understood. CD36 activation plays a role in the progression of CKD. However, the significance of CD36 during AKI-CKD, especially in pericyte, remains to be fully defined. Methods: GEO and DISCO database were used to analyze the expression of CD36 in pericyte during AKI-CKD; IRI to conduct AKI-CKD mouse model; Hypoxia/Reoxygenation (H/R) to induce the cell model; RT-qPCR and Western blotting to detect gene expression; IP and confocal-IF to determine the core fucosylation (CF) level of CD36. Flow cytometry (AV/PI staining) to detect the cell apoptosis and JC-1 staining to react to the change of mitochondrial membrane potential. Results: During AKI to CKD progression, CD36 expression in pericytes is higher and may be influenced by CF. Moreover, we confirmed the positive association of CD36 expression with pericyte-myofibroblast transition and the progression of AKI-CKD in an IRI mouse model and hypoxia/reoxygenation (H/R) pericytes. Notably, we discovered that FUT8 upregulates both CD36 expression and its CF level, contributing to the activation of the mitochondrial-dependent apoptosis signaling pathway in pericytes, ultimately leading to the progression of AKI-CKD. Conclusion: These results further identify FUT8 and CD36 as potential targets for the treatment in the progression of AKI-CKD.