On the in vitro and in vivo properties of four locked nucleic acid nucleotides incorporated into an anti-H-Ras antisense oligonucleotide

Chembiochem. 2005 Jun;6(6):1104-9. doi: 10.1002/cbic.200400419.


Locked nucleic acid (beta-D-LNA) monomers are conformationally restricted nucleotides bearing a methylene 2'-O, 4'-C linkage that have an unprecedented high affinity for matching DNA or RNA. In this study, we compared the in vitro and in vivo properties of four different LNAs, beta-D-amino LNA (amino-LNA), beta-D-thio LNA (thio-LNA), beta-D-LNA (LNA), and its stereoisomer alpha-L-LNA in an antisense oligonucleotide (ODN). A well-known antisense ODN design against H-Ras was modified at the 5'- and 3'-ends with the different LNA analogues (LNA-DNA-LNA gapmer design). The resulting gapmers were tested in cancer-cell cultures and in a nude-mouse model bearing prostate tumor xenografts. The efficacy in target knockdown, the biodistribution, and the ability to inhibit tumor growth were measured. All anti H-Ras ODNs were very efficient in H-Ras mRNA knockdown in vitro, reaching maximum effect at concentrations below 5 nM. Moreover, the anti-H-Ras ODN containing alpha-L-LNA had clearly the highest efficacy in H-Ras knockdown. All LNA types displayed a great stability in serum. ODNs containing amino-LNA showed an increased uptake by heart, liver, and lungs as compared to the other LNA types. Both alpha-L-LNA and LNA gapmer ODNs had a high efficacy of tumor-growth inhibition and were nontoxic at the tested dosages. Remarkably, in vivo tumor-growth inhibition could be observed at dosages as low as 0.5 mg kg(-1) per day. These results indicate that alpha-L-LNA is a very promising member of the family of LNA analogues in antisense applications.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Division / drug effects*
  • DNA / chemistry
  • DNA / metabolism
  • Dose-Response Relationship, Drug
  • Genes, ras / drug effects*
  • Male
  • Mice
  • Neoplasms, Experimental / drug therapy
  • Neoplasms, Experimental / metabolism
  • Nucleotides / chemistry*
  • Oligonucleotides
  • Oligonucleotides, Antisense / chemistry
  • Oligonucleotides, Antisense / metabolism
  • Oligonucleotides, Antisense / pharmacology*
  • RNA / chemistry
  • RNA / metabolism
  • RNA, Messenger / metabolism
  • Stereoisomerism
  • Tumor Cells, Cultured
  • Xenograft Model Antitumor Assays


  • Nucleotides
  • Oligonucleotides
  • Oligonucleotides, Antisense
  • RNA, Messenger
  • locked nucleic acid
  • RNA
  • DNA