title: Multidimensional Screening Platform for Simultaneously Targeting Oncogenic KRAS and Hypoxia-Inducible Factors Pathways in Colorectal Cancer.
abstract: Colorectal cancer (CRC) is a genetic disease, due to progressive accumulation of mutations in oncogenes and tumor suppressor genes. Large scale genomic sequencing projects revealed >100 mutations in any individual CRC. Many of these mutations are likely passenger mutations, and fewer are driver mutations. Of these, activating mutations in RAS proteins are essential for cancer initiation, progression, and/or resistance to therapy. There has been significant interest in developing drugs targeting mutated cancer gene products or downstream signaling pathways. Due to the number of mutations involved and inherent redundancy in intracellular signaling, drugs targeting one mutation or pathway have been either ineffective or led to rapid resistance. We have devised a strategy whereby multiple cancer pathways may be simultaneously targeted for drug discovery. For proof-of-concept, we targeted the oncogenic KRAS and HIF pathways, since oncogenic KRAS has been shown to be required for cancer initiation and progression, and HIF-1α and HIF-2α are induced by the majority of mutated oncogenes and tumor suppressor genes in CRC. We have generated isogenic cell lines defective in either oncogenic KRAS or both HIF-1α and HIF-2α and subjected them to multiplex genomic, siRNA, and high-throughput small molecule screening. We have identified potential drug targets and compounds for preclinical and clinical development. Screening of our marine natural product library led to the rediscovery of the microtubule agent dolastatin 10 and the class I histone deacetylase (HDAC) inhibitor largazole to inhibit oncogenic KRAS and HIF pathways. Largazole was further validated as an antiangiogenic agent in a HIF-dependent manner in human cells and in vivo in zebrafish using a genetic model with activated HIF. Our general strategy, coupling functional genomics with drug susceptibility or chemical-genetic interaction screens, enables the identification of potential drug targets and candidates with requisite selectivity. Molecules prioritized in this manner can easily be validated in suitable zebrafish models due to the genetic tractability of the system. Our multidimensional platform with cellular and organismal components can be extended to larger scale multiplex screens that include other mutations and pathways.
authors.affiliation: Institute of Molecular and Cell Biology (IMCB), A*STAR, Proteos , Singapore 138673, Singapore.
authors.forename: Michelle S
authors.initials: MS
authors.lastname: Bousquet
authors.affiliation: Institute of Molecular and Cell Biology (IMCB), A*STAR, Proteos , Singapore 138673, Singapore.
authors.forename: Jia Jia
authors.initials: JJ
authors.lastname: Ma
authors.forename: Ranjala
authors.initials: R
authors.lastname: Ratnayake
authors.forename: Pamela A
authors.initials: PA
authors.lastname: Havre
authors.forename: Jin
authors.initials: J
authors.lastname: Yao
authors.forename: Nam H
authors.initials: NH
authors.lastname: Dang
authors.affiliation: Smithsonian Marine Station , 701 Seaway Drive, Fort Pierce, Florida 34949, United States.
authors.forename: Valerie J
authors.initials: VJ
authors.lastname: Paul
authors.affiliation: Institute of Molecular and Cell Biology (IMCB), A*STAR, Proteos , Singapore 138673, Singapore.|Lee Kong Chian School of Medicine, Nanyang Technological University , 59 Nanyang Drive, 636921, Singapore.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Carney
authors.forename: Long H
authors.initials: LH
authors.lastname: Dang
authors.affiliation: Institute of Molecular and Cell Biology (IMCB), A*STAR, Proteos , Singapore 138673, Singapore.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Luesch
mesh_terms: D020533:Angiogenesis Inhibitors / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D051792:Basic Helix-Loop-Helix Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D001688:Biological Products / Q000737:chemistry / Q000494:pharmacology; D003106:Colon / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D004354:Drug Screening Assays, Antitumor / Q000379:methods; D055786:Gene Knockout Techniques; D045325:HCT116 Cells; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000037:antagonists & inhibitors / Q000378:metabolism*; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D012007:Rectum / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction / Q000187:drug effects; D054852:Small Molecule Libraries / Q000737:chemistry / Q000494:pharmacology*; D059467:Transcriptome / Q000187:drug effects; D015027:Zebrafish; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D020533:Angiogenesis Inhibitors; D000970:Antineoplastic Agents; D051792:Basic Helix-Loop-Helix Proteins; D001688:Biological Products; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D016283:Proto-Oncogene Proteins p21(ras); D034741:RNA, Small Interfering; D054852:Small Molecule Libraries; D000099162:Endothelial PAS Domain-Containing Protein 1; C117307:KRAS protein, human