title: Silencing of ROR1 and FMOD with siRNA results in apoptosis of CLL cells.
abstract: We have previously demonstrated that ROR1 and FMOD (fibromodulin) are two genes upregulated in chronic lymphocytic leukaemia (CLL) cells compared to normal blood B cells. In this study, siRNAs were used to specifically silence ROR1 and FMOD expression in CLL cells, healthy B cells and human fibroblast cell lines. siRNA treatment induced a specific reduction (75-95%) in FMOD and ROR1 mRNA. Western blot analysis with specific antibodies for FMOD and ROR1 demonstrated that the proteins were significantly downregulated 48 h after siRNA treatment. Silencing of FMOD and ROR1 resulted in statistically significant (P ≤ 0·05-0·001) apoptosis of CLL cells but not of B cells from normal donors. Human fibroblast cell lines treated with FMOD and ROR1 siRNA did not undergo apoptosis. This is the first report demonstrating that ROR1 and FMOD may be involved in the survival of CLL cells. ROR1 in particular is further explored as potential target for therapy in CLL.
authors.affiliation: Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Aniruddha
authors.initials: A
authors.lastname: Choudhury
authors.forename: Katja
authors.initials: K
authors.lastname: Derkow
authors.forename: Amir Hossein
authors.initials: AH
authors.lastname: Daneshmanesh
authors.forename: Eva
authors.initials: E
authors.lastname: Mikaelsson
authors.forename: Shahryar
authors.initials: S
authors.lastname: Kiaii
authors.forename: Parviz
authors.initials: P
authors.lastname: Kokhaei
authors.forename: Anders
authors.initials: A
authors.lastname: Osterborg
authors.forename: Håkan
authors.initials: H
authors.lastname: Mellstedt
mesh_terms: D017209:Apoptosis / Q000235:genetics*; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis / Q000235:genetics*; D000071235:Fibromodulin; D020868:Gene Silencing; D052138:Genes, Neoplasm; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000473:pathology; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D011509:Proteoglycans / Q000096:biosynthesis / Q000235:genetics*; D012334:RNA, Neoplasm / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D057050:Receptor Tyrosine Kinase-like Orphan Receptors / Q000096:biosynthesis / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D016326:Extracellular Matrix Proteins; C000604330:FMOD protein, human; D009363:Neoplasm Proteins; D011509:Proteoglycans; D012334:RNA, Neoplasm; D034741:RNA, Small Interfering; D000071235:Fibromodulin; C078716:ROR1 protein, human; D057050:Receptor Tyrosine Kinase-like Orphan Receptors