Peptide Conjugates of Oligonucleotide Analogs and siRNA for Gene Expression Modulation

18.1 The Challenge of Delivery of Oligonucleotide Analogs and siRNA into Cells in Culture and In Vivo ............................................ 313 18.2 Chemical Synthesis of Peptide–Oligonucleotide Conjugates .............. 314 18.2.1 Synthesis of CPP Conjugates to Phosphate-Containing Oligonucleotides ...................................................................... 315 18.2.2 Synthesis of PNA–Peptide Conjugates .................................... 318 18.3 Gene Expression Modulation by Peptide Conjugates of Antisense or Steric Block Oligonucleotides .......................................................... 318 18.3.1 Anionic Oligonucleotide Analog Conjugates with CPPs ........ 318 18.3.2 Charge-Neutral PNA and PMO Oligonucleotide Conjugates with CPPs .............................................................. 320 18.4 Gene Expression Inhibition by Peptide Conjugates of siRNA ............ 323 18.5 Future Perspectives ................................................................................ 324 Acknowledgments ............................................................................................ 325 References ........................................................................................................ 325