RNAseq changes in mouse wound with or without time course treatment by Vemurafenib

BRAF inhibitors are highly effective therapies for patients with BRAF V600 mutated metastatic melanoma. Patients who receive BRAF inhibitors develop a variety of hyper-proliferative skin conditions, whose pathogenic basis is the paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway in BRAF wild-type cells. Most of these hyper-proliferative skin changes improve when a MEK inhibitor is co-administered, as a MEK inhibitor blocks paradoxical MAPK activation. We tested whether we could take advantage of the mechanistic understanding of the skin hyper-proliferative side effects of BRAF inhibitors to accelerate skin wound healing by inducing paradoxical MAPK activation. Here we show that the BRAF inhibitor vemurafenib accelerates human keratinocyte proliferation and migration by increasing ERK phosphorylation and cell cycle progression. Topical treatment with vemurafenib in two wound-healing models in mice accelerated cutaneous wound healing and improved the tensile strength of healing wounds through paradoxical MAPK activation; addition of a MEK inhibitor reversed the benefit of vemurafenib-accelerated wound healing. The same dosing regimen of topical BRAF inhibitor did not increase the incidence of cutaneous squamous cell carcinomas in mice even after the application of a carcinogen. Therefore, topical BRAF inhibitors may have clinical applications in accelerating the healing of skin wounds. Overall design: Full depth incisional wound mice tissues with/without Vemurafenib treatment were sent for RNAseq analysis on day 2, 6 and 14

BRAF抑制剂（BRAF inhibitor）是针对BRAF V600突变转移性黑色素瘤患者的高效治疗手段。接受BRAF抑制剂治疗的患者可出现多种过度增殖性皮肤病变，其致病基础为BRAF野生型细胞中丝裂原活化蛋白激酶（mitogen-activated protein kinase, MAPK）通路的悖论性激活。多数此类过度增殖性皮肤改变在联合应用MEK抑制剂后可得到改善，因MEK抑制剂可阻断该悖论性MAPK激活。我们尝试依托对BRAF抑制剂所致皮肤过度增殖性不良反应的机制认知，通过诱导悖论性MAPK激活来加速皮肤伤口愈合。本研究证实，BRAF抑制剂维莫非尼（vemurafenib）可通过增强ERK磷酸化水平与细胞周期进程，促进人角质形成细胞的增殖与迁移。在两种小鼠伤口愈合模型中，局部给予维莫非尼可通过悖论性MAPK激活加速皮肤伤口愈合，并提升愈合伤口的抗张强度；联合使用MEK抑制剂则会逆转维莫非尼对伤口愈合的促进作用。即便在给予致癌物的情况下，该局部BRAF抑制剂给药方案也未增加小鼠皮肤鳞状细胞癌的发生率。因此，局部应用BRAF抑制剂或可在临床中用于加速皮肤伤口愈合。整体实验设计：于第2、6、14天采集接受与未接受维莫非尼治疗的小鼠全层切口伤口组织，进行RNA测序（RNAseq）分析。