Repression of STAT3, STAT5A, and STAT5B expressions in chronic myelogenous leukemia cell line K-562 with unmodified or chemically modified siRNAs and induction of apoptosis.
Signal transducers and activators of transcription (STAT) proteins are latent cytoplasmic transcription factors that affect several cellular processes including cell growth, proliferation, differentiation, and survival. Following phosphorylation, STATs are activated, and their upregulated expressions increase in malignancies with playing a role in the development of leukemia. In this study, transfection of K-562 cells with either unmodified or chemically modified anti-STAT3, -STAT5A, -STAT5B siRNAs for duration of 12 days, determining gene silencing at mRNA and protein levels, evaluating apoptosis rate, and detecting JAK/STAT pathway members' gene expression profiles via array method were aimed. Quantitative RT-PCR and Western blot assays indicated that STAT expressions were downregulated both at mRNA and protein levels, and TUNEL assay showed that leukemic cell apoptosis was induced due to inhibition of STATs. Array analysis resulted with decreases in signal transducer, phosphorylation inducer, and oncogene expressions, whereas increased expressions in STAT inhibitor and apoptosis inducer genes were observed. These results point out that siRNA application could constitute a new and alternative curative method for supporting therapy of CML-diagnosed patients in the future.
Faculty of Medicine Department of Medical Biology, Ege University, Bornova, Izmir, Turkey. burcin.tezcanli@ege.edu.tr
Burçin Tezcanlı
BT
Kaymaz
Nur
N
Selvi
Cumhur
C
Gündüz
Cağdaş
C
Aktan
Ayşegül
A
Dalmızrak
Güray
G
Saydam
Buket
B
Kosova
D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D015153:Blotting, Western; D004354:Drug Screening Assays, Antitumor; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects*; D006801:Humans; D020014:K562 Cells / Q000187:drug effects / Q000378:metabolism; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000473:pathology*; D058990:Molecular Targeted Therapy; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D034622:RNA Interference; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012334:RNA, Neoplasm / Q000096:biosynthesis / Q000235:genetics; D034741:RNA, Small Interfering / Q000138:chemical synthesis / Q000235:genetics / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D050796:STAT3 Transcription Factor / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D050799:STAT5 Transcription Factor / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects; D014162:Transfection; D025521:Tumor Suppressor Proteins / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics
D009363:Neoplasm Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D034741:RNA, Small Interfering; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D050799:STAT5 Transcription Factor; C494092:STAT5A protein, human; C494095:STAT5B protein, human; D025521:Tumor Suppressor Proteins