title: Genomewide RNAi screen identifies protein kinase Cb and new members of mitogen-activated protein kinase pathway as regulators of melanoma cell growth and metastasis.
abstract: A large-scale RNAi screen was performed for eight different melanoma cell lines using a pooled whole-genome lentiviral shRNA library. shRNAs affecting proliferation of transduced melanoma cells were negatively selected during 10 days of culture. Overall, 617 shRNAs were identified by microarray hybridization. Pathway analyses identified mitogen-activated protein kinase (MAPK) pathway members such as ERK1/2, JNK1/2 and MAP3K7 and protein kinase C β (PKCβ) as candidate genes. Knockdown of PKCβ most consistently reduced cellular proliferation, colony formation and migratory capacity of melanoma cells and was selected for further validation. PKCβ showed enhanced expression in human primary melanomas and distant metastases as compared with benign melanocytic nevi. Moreover, treatment of melanoma cells with PKCβ-specific inhibitor enzastaurin reduced melanoma cell growth but had only small effects on benign fibroblasts. Finally, PKCβ-shRNA significantly reduced lung colonization capacity of stably transduced melanoma cells in mice. Taken together, this study identified new candidate genes for melanoma cell growth and proliferation. PKCβ seems to play an important role in these processes and might serve as a new target for the treatment of metastatic melanoma.
authors.affiliation: Department of Dermatology, Venereology and Allergology, University of Leipzig, Leipzig, Germany.
authors.forename: Madeleine
authors.initials: M
authors.lastname: Schönherr
authors.forename: Animesh
authors.initials: A
authors.lastname: Bhattacharya
authors.forename: Tina
authors.initials: T
authors.lastname: Kottek
authors.forename: Silke
authors.initials: S
authors.lastname: Szymczak
authors.forename: Margarethe
authors.initials: M
authors.lastname: Köberle
authors.forename: Claudia
authors.initials: C
authors.lastname: Wickenhauser
authors.forename: Udo
authors.initials: U
authors.lastname: Siebolts
authors.forename: Anja
authors.initials: A
authors.lastname: Saalbach
authors.forename: Dirk
authors.initials: D
authors.lastname: Koczan
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Magin
authors.forename: Jan C
authors.initials: JC
authors.lastname: Simon
authors.forename: Manfred
authors.initials: M
authors.lastname: Kunz
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D004790:Enzyme Induction; D015972:Gene Expression Regulation, Neoplastic; D015698:Genomic Library; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008175:Lung Neoplasms / Q000517:prevention & control / Q000556:secondary; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology*; D008545:Melanoma / Q000201:enzymology / Q000473:pathology* / Q000517:prevention & control / Q000556:secondary; D051379:Mice; D008810:Mice, Inbred C57BL; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D009508:Nevus, Pigmented / Q000201:enzymology; D020411:Oligonucleotide Array Sequence Analysis; D064546:Protein Kinase C beta / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011494:Protein Kinases / Q000235:genetics / Q000502:physiology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000494:pharmacology*; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D012878:Skin Neoplasms / Q000201:enzymology; D014161:Transduction, Genetic; D014410:Tumor Stem Cell Assay; D015854:Up-Regulation
chemical_list: D007211:Indoles; D009363:Neoplasm Proteins; D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; D011494:Protein Kinases; D020794:Receptor Protein-Tyrosine Kinases; D064546:Protein Kinase C beta; C504878:enzastaurin
keywords: RNA interference; intracellular signaling; melanoma biology; tumor metastasis