A hybrid DNA/RNA molecule, called htiRNA hybrid, comprising: - two antisense RNA strands of same sequences and able to modulate endogenous mechanisms of RNA interference, each comprising a number of nucleotides n RNA from 18 to 30, and having a phosphorylated 5' end; - a first DNA strand, having a nucleotide sequence comprising a nucleotide sequence S1 linked via its 3' end to the 5' end of a nucleotide spacer arm L1 linked by its 3' end to the 5' end of a nucleotide sequence SC1, and - a second DNA strand, having a nucleotide sequence comprising a nucleotide sequence S2 linked via its 3' end to the 5' end of a nucleotide spacer arm L2 inked via its 3' end to the 5' end of a nucleotide sequence SC2, wherein: - the nucleotide sequence SC1 comprises a number n SC1 of nucleotides with n SC1 from (n RNA - 3) to (n RNA + 3), and has at least 40 % sequence identity, determined by a global alignment method, with the complementary sequence of the antisense RNA, so that the nucleotide sequence SC1 is hybridized via complementarity to a first of the two antisense RNA strands; - the nucleotide sequence SC2 comprises a number n SC2 of nucleotides with n SC2 from (n RNA - 3) to (n RNA + 3), and has at least 40 % sequence identity, determined by a global alignment method, with the complementary sequence of the antisense RNA, so that the nucleotide sequence SC2 is hybridized via complementarity to the second of the two antisense RNA strands; - the nucleotide sequence S1 of the first DNA strand is complementary to the nucleotide sequence S2 of the second DNA strand, so that the nucleotide sequence S1 of the first DNA strand is hybridized via complementarity to the nucleotide sequence S2 of the second DNA strand; - the two nucleotide sequences S1 and S2 have the same number n S1-S2 of nucleotides, n S1-S2 being a number of 16 to 30; - the nucleotide spacer arm L1 of the first DNA strand comprises a number n L1 of nucleotides and the nucleotide spacer arm L2 of the second DNA strand comprises a number n L2 of nucleotides, n L1 and n L2 independently being a number of 1 to 15; - the two antisense RNA strands, the first DNA strand and/or the second DNA strand optionally carry one or more lipid groups. - two antisense RNA strands of same sequences and able to modulate endogenous mechanisms of RNA interference, each comprising a number of nucleotides n RNA from 18 to 30, and having a phosphorylated 5' end; - a first DNA strand, having a nucleotide sequence comprising a nucleotide sequence S1 linked via its 3' end to the 5' end of a nucleotide spacer arm L1 linked by its 3' end to the 5' end of a nucleotide sequence SC1, and - a second DNA strand, having a nucleotide sequence comprising a nucleotide sequence S2 linked via its 3' end to the 5' end of a nucleotide spacer arm L2 inked via its 3' end to the 5' end of a nucleotide sequence SC2, - the nucleotide sequence SC1 comprises a number n SC1 of nucleotides with n SC1 from (n RNA - 3) to (n RNA + 3), and has at least 40 % sequence identity, determined by a global alignment method, with the complementary sequence of the antisense RNA, so that the nucleotide sequence SC1 is hybridized via complementarity to a first of the two antisense RNA strands; - the nucleotide sequence SC2 comprises a number n SC2 of nucleotides with n SC2 from (n RNA - 3) to (n RNA + 3), and has at least 40 % sequence identity, determined by a global alignment method, with the complementary sequence of the antisense RNA, so that the nucleotide sequence SC2 is hybridized via complementarity to the second of the two antisense RNA strands; - the nucleotide sequence S1 of the first DNA strand is complementary to the nucleotide sequence S2 of the second DNA strand, so that the nucleotide sequence S1 of the first DNA strand is hybridized via complementarity to the nucleotide sequence S2 of the second DNA strand; - the two nucleotide sequences S1 and S2 have the same number n S1-S2 of nucleotides, n S1-S2 being a number of 16 to 30; - the nucleotide spacer arm L1 of the first DNA strand comprises a number n L1 of nucleotides and the nucleotide spacer arm L2 of the second DNA strand comprises a number n L2 of nucleotides, n L1 and n L2 independently being a number of 1 to 15; - the two antisense RNA strands, the first DNA strand and/or the second DNA strand optionally carry one or more lipid groups.