title: Anti-tumor activity of splice-switching oligonucleotides.
abstract: Alternative splicing has emerged as an important target for molecular therapies. Splice-switching oligonucleotides (SSOs) modulate alternative splicing by hybridizing to pre-mRNA sequences involved in splicing and blocking access to the transcript by splicing factors. Recently, the efficacy of SSOs has been established in various animal disease models; however, the application of SSOs against cancer targets has been hindered by poor in vivo delivery of antisense therapeutics to tumor cells. The apoptotic regulator Bcl-x is alternatively spliced to express anti-apoptotic Bcl-x(L) and pro-apoptotic Bcl-x(S). Bcl-x(L) is upregulated in many cancers and is associated with chemoresistance, distinguishing it as an important target for cancer therapy. We previously showed that redirection of Bcl-x pre-mRNA splicing from Bcl-x(L) to -x(S) induced apoptosis in breast and prostate cancer cells. In this study, the effect of SSO-induced Bcl-x splice-switching on metastatic melanoma was assessed in cell culture and B16F10 tumor xenografts. SSOs were delivered in vivo using lipid nanoparticles. Administration of nanoparticle with Bcl-x SSO resulted in modification of Bcl-x pre-mRNA splicing in lung metastases and reduced tumor load, while nanoparticle alone or formulated with a control SSO had no effect. Our findings demonstrate in vivo anti-tumor activity of SSOs that modulate Bcl-x pre-mRNA splicing.
authors: Department of Pharmacology and Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA. john_bauman@med.unc.edu
authors: John A
authors: JA
authors: Bauman
authors: Shyh-Dar
authors: SD
authors: Li
authors: Angela
authors: A
authors: Yang
authors: Leaf
authors: L
authors: Huang
authors: Ryszard
authors: R
authors: Kole
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D045744:Cell Line, Tumor; D005260:Female; D008546:Melanoma, Experimental / Q000235:genetics / Q000473:pathology / Q000628:therapy*; D051379:Mice; D008810:Mice, Inbred C57BL; D053758:Nanoparticles / Q000633:toxicity; D009841:Oligonucleotides / Q000008:administration & dosage* / Q000737:chemistry; D012322:RNA Precursors / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051020:bcl-X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: C494812:Bcl2l1 protein, mouse; D009841:Oligonucleotides; D012322:RNA Precursors; D012333:RNA, Messenger; D051020:bcl-X Protein