Abstract: The invention relates to double-stranded nucleic acid fragments comprising a chemically modified backbone and at least 4-1000 bp, preferably 8-500 bp, and most preferably 16-200 bp. The disclosed molecules (DRIL molecules) may interfere with DNA damage signalling and repair pathways, in particular the non homologous NHEJ pathway of double-stranded break repair. The invention discloses the application of the DRIL molecules as adjuvant compositions to be used in association with a DNA breaking treatment, particularly radiotherapy or chemotherapy, in combination with a pharmaceutically acceptable carrier, in an efficient amount to be introduced in the tumoral cell nuclei in order to trigger DNA repair induced lethality (DRIL in short) of tumoral cells/tissues.

Abstract: The invention relates to compositions and methods for interfering with the DNA repair of double strand breaks (DSBs). The invention discloses novel double-stranded nucleic acid molecules. that act as baits and hijack the holocomplex of enzymes responsible of DNA DSB sensing, signaling and/or repair pathways, in particular the non homologous end joining (NHEJ) pathway of DSB repair. The invention discloses the use of these molecules as adjuvant compositions to be used in association with a DNA breaking treatment, particularly radiotherapy or chemotherapy, in combination with a pharmaceutically acceptable carrier, in an efficient amount to be introduced in the tumor cell nuclei in order to neutralize transiently their DNA repair capacity and trigger their death.

Abstract: This invention concerns a method for effecting directed mutagenesis based on a guided homologous recombination system that comprises (i) a triple helix forming oligonucleotide, (ii) a donor nucleic acid segment, and (iii) an adapter segment comprising an oligonucleotide sequence able to bind at least a portion of said donor nucleic acid through Watson-Crick base pairing.

Abstract: This invention concerns a method for effecting directed mutagenesis based on a guided homologous recombination system that comprises (i) a triple helix forming oligonucleotide, (ii) a donor nucleic acid segment, and (iii) an adapter segment comprising an oligonucleotide sequence able to bind at least a portion of said donor nucleic acid through Watson-Crick base pairing.