Le Xiuning, Langenau David M, Keefe Matthew D, Kutok Jeffery L, Neuberg Donna S, Zon Leonard I
Stem Cell Program and Division of Hematology/Oncology, Children's Hospital, Boston, MA 02115, USA.
Proc Natl Acad Sci U S A. 2007 May 29;104(22):9410-5. doi: 10.1073/pnas.0611302104. Epub 2007 May 21.
RAS family members are among the most frequently mutated oncogenes in human cancers. Given the utility of zebrafish in both chemical and genetic screens, developing RAS-induced cancer models will make large-scale screens possible to understand further the molecular mechanisms underlying malignancy. We developed a heat shock-inducible Cre/Lox-mediated transgenic approach in which activated human kRASG12D can be conditionally induced within transgenic animals by heat shock treatment. Specifically, double transgenic fish Tg(B-actin-LoxP-EGFP-LoxP-kRASG12D; hsp70-Cre) developed four types of tumors and hyperplasia after heat shock of whole zebrafish embryos, including rhabdomyosarcoma, myeloproliferative disorder, intestinal hyperplasia, and malignant peripheral nerve sheath tumor. Using ex vivo heat shock and transplantation of whole kidney marrow cells from double transgenic animals, we were able to generate specifically kRASG12D-induced myeloproliferative disorder in recipient fish. This heat shock-inducible recombination approach allowed for the generation of multiple types of RAS-induced tumors and hyperplasia without characterizing tissue-specific promoters. Moreover, these tumors and hyperplasia closely resemble human diseases at both the morphologic and molecular levels.
RAS家族成员是人类癌症中最常发生突变的致癌基因之一。鉴于斑马鱼在化学和遗传筛选中的实用性，开发RAS诱导的癌症模型将使大规模筛选成为可能，从而进一步了解恶性肿瘤的分子机制。我们开发了一种热休克诱导的Cre/Lox介导的转基因方法，通过热休克处理，可在转基因动物体内条件性诱导激活的人类kRASG12D。具体而言，双转基因鱼Tg(B-肌动蛋白-LoxP-EGFP-LoxP-kRASG12D; hsp70-Cre)在对整个斑马鱼胚胎进行热休克处理后出现了四种类型的肿瘤和增生，包括横纹肌肉瘤、骨髓增殖性疾病、肠道增生和恶性外周神经鞘瘤。通过对双转基因动物进行离体热休克和全骨髓细胞移植，我们能够在受体鱼中特异性地产生kRASG12D诱导的骨髓增殖性疾病。这种热休克诱导的重组方法无需表征组织特异性启动子就能产生多种类型的RAS诱导的肿瘤和增生。此外，这些肿瘤和增生在形态和分子水平上都与人类疾病极为相似。
