1 The University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, Queensland, Australia.
Mater Research Institute, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia.
SLAS Discov. 2017 Mar;22(3):298-308. doi: 10.1177/1087057116679592. Epub 2016 Nov 23.
Malignant melanomas often arise from nevi, which result from initial oncogene-induced hyperproliferation of melanocytes that are maintained in a CDKN2A/p16-mediated senescent state. Thus, genes that can bypass this senescence barrier are likely to contribute to melanoma development. We have performed a gain-of-function screen of 17,030 lentivirally expressed human open reading frames (ORFs) in a melanoma cell line containing an inducible p16 construct to identify such genes. Genes known to bypass p16-induced senescence arrest, including the human papilloma virus 18 E7 gene ( HPV18E7), and genes such as the p16-binding CDK6 with expected functions, as well as panel of novel genes, were identified, including high-mobility group box (HMGB) proteins. A number of these were further validated in two other models of p16-induced senescence. Tissue immunohistochemistry demonstrated higher levels of CDK6 in primary melanomas compared with normal skin and nevi. Reduction of CDK6 levels drove melanoma cells expressing functional p16 into senescence, demonstrating its contribution to bypass senescence.
恶性黑色素瘤通常起源于痣，痣是由黑素细胞最初的致癌基因诱导过度增殖引起的，这些黑素细胞处于 CDKN2A/p16 介导的衰老状态。因此，能够绕过这种衰老障碍的基因可能有助于黑色素瘤的发展。我们在含有诱导型 p16 构建体的黑色素瘤细胞系中进行了 17030 个人类开放阅读框 (ORF) 的功能获得筛选，以鉴定此类基因。鉴定出了已知能够绕过 p16 诱导的衰老阻滞的基因，包括人乳头瘤病毒 18 E7 基因 (HPV18E7)，以及具有预期功能的 p16 结合 CDK6 等基因，以及一系列新基因，包括高迁移率族蛋白 (HMGB) 蛋白。其中一些在另外两种 p16 诱导的衰老模型中得到了进一步验证。组织免疫组织化学显示，与正常皮肤和痣相比，原发性黑色素瘤中 CDK6 的水平更高。降低 CDK6 水平可使表达功能性 p16 的黑色素瘤细胞进入衰老状态，表明其对绕过衰老的贡献。
