title: Oligonucleotide aptamer-drug conjugates for targeted therapy of acute myeloid leukemia.
abstract: Oligonucleotide aptamers can specifically bind biomarkers on cancer cells and can be readily chemically modified with different functional molecules for personalized medicine. To target acute myeloid leukemia (AML) cells, we developed a single-strand DNA aptamer specific for the biomarker CD117, which is highly expressed on AML cells. Sequence alignment revealed that the aptamer contained a G-rich core region with a well-conserved functional G-quadruplex structure. Functional assays demonstrated that this synthetic aptamer was able to specifically precipitate CD117 proteins from cell lysates, selectively bound cultured and patient primary AML cells with high affinity (Kd < 5 nM), and was specifically internalized into CD117-expressing cells. For targeted AML treatment, aptamer-drug conjugates were fabricated by chemical synthesis of aptamer (Apt) with methotrexate (MTX), a central drug used in AML chemotherapy regimens. The formed Apt-MTX conjugates specifically inhibited AML cell growth, triggered cell apoptosis, and induced cell cycle arrest in G1 phase. Importantly, Apt-MTX had little effect on CD117-negative cells under the same treatment conditions. Moreover, exposure of patient marrow specimens to Apt-MTX resulted in selective growth inhibition of primary AML cells and had no toxicity to off-target background normal marrow cells within the same specimens. These findings indicate the potential clinical value of Apt-MTX for targeted AML therapy with minimal to no side effects in patients, and also open an avenue to chemical synthesis of new, targeted biotherapeutics.
authors.affiliation: Department of Pathology and Genomic Medicine, Houston Methodist Hospital, and Cancer Pathology Laboratory, Houston Methodist Research Institute, Houston, TX, 77030, USA.
authors.forename: Nianxi
authors.initials: N
authors.lastname: Zhao
authors.affiliation: Department of Pathology and Genomic Medicine, Houston Methodist Hospital, and Cancer Pathology Laboratory, Houston Methodist Research Institute, Houston, TX, 77030, USA.
authors.forename: Sung-Nan
authors.initials: SN
authors.lastname: Pei
authors.affiliation: Department of Pathology and Genomic Medicine, Houston Methodist Hospital, and Cancer Pathology Laboratory, Houston Methodist Research Institute, Houston, TX, 77030, USA.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Qi
authors.affiliation: Department of Pathology and Genomic Medicine, Houston Methodist Hospital, and Cancer Pathology Laboratory, Houston Methodist Research Institute, Houston, TX, 77030, USA.
authors.forename: Zihua
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Houston Methodist Cancer Center, Houston, TX, 77030, USA.
authors.forename: Swaminathan P
authors.initials: SP
authors.lastname: Iyer
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
authors.forename: Pei
authors.initials: P
authors.lastname: Lin
authors.affiliation: Molecular Imaging Innovations Institute, Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA.
authors.forename: Ching-Hsuan
authors.initials: CH
authors.lastname: Tung
authors.affiliation: Department of Pathology and Genomic Medicine, Houston Methodist Hospital, and Cancer Pathology Laboratory, Houston Methodist Research Institute, Houston, TX, 77030, USA. Electronic address: yzu@houstonmethodist.org.
authors.forename: Youli
authors.initials: Y
authors.lastname: Zu
mesh_terms: D052157:Aptamers, Nucleotide / Q000494:pharmacology / Q000627:therapeutic use*; D001483:Base Sequence; D001853:Bone Marrow / Q000187:drug effects / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004277:DNA, Single-Stranded; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy* / Q000473:pathology; D008727:Methotrexate / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D008969:Molecular Sequence Data; D058990:Molecular Targeted Therapy; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism
chemical_list: D052157:Aptamers, Nucleotide; D004277:DNA, Single-Stranded; D019009:Proto-Oncogene Proteins c-kit; D008727:Methotrexate
keywords: Acute myeloid leukemia (AML); Aptamer-drug conjugates; CD117 biomarker; Methotrexate (MTX); Oligonucleotide aptamer; Targeted therapy