The purpose of the present invention is to provide novel miR-143 derivatives described herein that can be used as oligonucleotide therapeutics. A microRNA-143 derivative wherein the first strand is an oligonucleotide consisting of a sequence of SEQ ID NO: 3； or a sequence in which one or two bases are substituted, deleted, inserted or added to the sequence of SEQ ID NO: 3 and does not include a 3'-end modification, but may include a 5'-end modification； and the second strand is an oligonucleotide consisting of a sequence of SEQ ID NO: 4 or a sequence in which one or two bases are substituted, deleted or inserted to the sequence of SEQ ID NO: 4 and includes a 3'-end modification, and may include a 5'-end modification； or a sequence of SEQ ID NO: 5 or a sequence in which one or two bases are substituted or inserted to the sequence of SEQ ID NO: 5 and does not include a 3'-end modification, and may include a 5'-end modification； wherein the 3'-end modification is a 1 to 5-mer oligonucleotide derivative which may include a nucleoside derivative(s) and/or modified internucleoside linkage(s) or a benzene-pyridine derivative and the 5'-end modification is a phosphate ester moiety or a group of the formula: =CQ 1 - P(=O)(OH) 2 , wherein Q 1 is hydrogen, halogen, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, or substituted or unsubstituted alkyloxy.
