Long　non-coding　RNAs　(IncRNAs)　are　defined　as　a　class　of　RNA　transcripts　longer　than　200　nucleotides　encoded　by　mammalian　genomes　that　lack　protein-coding　potential.　LncRNA　ASBEL　has　been　identified　as　an　anti-sense　transcript　of　BTG3　(B　cell　translocation　gene　3)　gene,　which　encodes　an　anti-proliferation　protein.　Remarkable　down-regulation　of　BTG3　has　been　reported　in　triple-negative　breast　cancer　(TNBC).　In　the　present　study,　a　number　of　single-stranded　modified　anti-sense　DNA　oligonucleotides　(antago)　were　designed,　synthesized　and　screened　for　specific　IncRNA　ASBEL　knockdown.　We　showed　here　that　anti-ASBEL　antago　played　a　significant　tumor　suppressive　role　in　TNBC　by　effective　down-regulating　IncRNA　ASBEL,　which　in　turn　led　to　increased　BTG3　expression.　The　obtained　data　suggest　IncRNA　ASBEL　as　a　novel　therapeutic　target　in　TNBC.　(C)　2017　Elsevier　Inc.　All　rights　reserved.