title: Reprofiling using a zebrafish melanoma model reveals drugs cooperating with targeted therapeutics.
abstract: Phenotype-guided re-profiling of approved drug molecules presents an accelerated route to developing anticancer therapeutics by bypassing the target-identification bottleneck of target-based approaches and by sampling drugs already in the clinic. Further, combinations incorporating targeted therapies can be screened for both efficacy and toxicity. Previously we have developed an oncogenic-RAS-driven zebrafish melanoma model that we now describe display melanocyte hyperplasia while still embryos. Having devised a rapid method for quantifying melanocyte burden, we show that this phenotype can be chemically suppressed by incubating V12RAS transgenic embryos with potent and selective small molecule inhibitors of either MEK or PI3K/mTOR. Moreover, we demonstrate that combining MEK inhibitors (MEKi) with dual PI3K/mTOR inhibitors (PI3K/mTORi) resulted in a super-additive suppression of melanocyte hyperplasia. The robustness and simplicity of our novel screening assay inspired us to perform a modest screen of FDA approved compounds for their ability to potentiate MEKi PD184352 or PI3K/mTORi NVPBEZ235 suppression of V12RAS-driven melanocyte hyperplasia. Through this route, we confirmed Rapamycin as a compound that could synergize with MEKi and even more so with PI3K/mTORi to suppress melanoma development, including suppressing the growth of cultured human melanoma cells. Further, we discovered two additional compounds-Disulfiram and Tanshinone-that also co-operate with MEKi to suppress the growth of transformed zebrafish melanocytes and showed activity toward cultured human melanoma cells. In conclusion, we provide proof-of-concept that our phenotype-guided screen could be used to identify compounds that affect melanoma development and prompt further evaluation of Disulfiram and Tanshinone as possible partners for combination therapy.
authors.affiliation: Faculty of Life Sciences, The University of Manchester, Manchester, UK.
authors.forename: Laura
authors.initials: L
authors.lastname: Fernandez Del Ama
authors.affiliation: Faculty of Life Sciences, The University of Manchester, Manchester, UK.
authors.forename: Mary
authors.initials: M
authors.lastname: Jones
authors.affiliation: Faculty of Life Sciences, The University of Manchester, Manchester, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Walker
authors.affiliation: Faculty of Life Sciences, The University of Manchester, Manchester, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Chapman
authors.affiliation: Faculty of Life Sciences, The University of Manchester, Manchester, UK.
authors.forename: Julia A
authors.initials: JA
authors.lastname: Braun
authors.affiliation: Faculty of Life Sciences, The University of Manchester, Manchester, UK.
authors.forename: Jasmine
authors.initials: J
authors.lastname: Mohr
authors.affiliation: Faculty of Life Sciences, The University of Manchester, Manchester, UK.
authors.forename: Adam F L
authors.initials: AF
authors.lastname: Hurlstone
mesh_terms: D045784:Abietanes / Q000008:administration & dosage; D000818:Animals; D030801:Animals, Genetically Modified; D017209:Apoptosis / Q000187:drug effects; D001549:Benzamides / Q000737:chemistry; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D004221:Disulfiram / Q000008:administration & dosage; D058492:Drug Repositioning; D004791:Enzyme Inhibitors / Q000737:chemistry; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D020930:MAP Kinase Kinase Kinases / Q000037:antagonists & inhibitors*; D008543:Melanins / Q000737:chemistry; D008544:Melanocytes / Q000166:cytology; D008545:Melanoma / Q000188:drug therapy*; D016376:Oligonucleotides, Antisense / Q000235:genetics; D010641:Phenotype; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D020123:Sirolimus / Q000737:chemistry; D012878:Skin Neoplasms / Q000188:drug therapy*; D015027:Zebrafish
chemical_list: C120227:2-(2-chloro-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluorobenzamide; D045784:Abietanes; D001549:Benzamides; D004791:Enzyme Inhibitors; D008543:Melanins; D016376:Oligonucleotides, Antisense; D047428:Protein Kinase Inhibitors; C021751:tanshinone; D020930:MAP Kinase Kinase Kinases; D004221:Disulfiram; D020123:Sirolimus
keywords: MEK; PI3K; mTOR; melanoma; zebrafish