Negin Gogani
1, Marveh Rahmati
2, Nosratollah Zarghami
2,3, Iraj Asvadi-Kermani
3, Mohammad Ali Hoseinpour-Feyzi
1, Mohammad Amin Moosavi
1,3,4*1 Department of Zoology, Faculty of Natural Science, University of Tabriz, Tabriz, Iran.
2 Department of Biochemistry, Faculty of Medicine, Tabriz University of Medical Science, Tabriz, Iran.
3 Hematology and Oncology Research Center, Tabriz University of Medical Science, Tabriz, Iran.
4 National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
Abstract
Abstract
Purpose:
Despite significant improvements in treatment of chronic myelogenous leukemia
(CML), the emergence of leukemic stem cell (LSC) concept questioned efficacy of
current therapeutical protocols. Remaining issue on CML includes finding and
targeting of the key genes responsible for self-renewal and proliferation of
LSCs. Nucleostemin (NS) is a new protein localized in the nucleolus of most
stem cells and tumor cells which regulates their self-renewal and cell cycle
progression. The aim of this study was to investigate effects of NS
knocking down in K562 cell line as an in vitro model of CML.
Methods:
NS gene silencing
was performed using a specific small interfering RNA (NS-siRNA). The gene
expression level of NS was evaluated by RT-PCR. The viability and growth rate of K562 cells were determined
by trypan blue exclusion test. Cell cycle distribution of the cells was
analyzed by flow cytometry.
Results:
Our results showed that NS knocking down inhibited proliferation and
viability of K562 cells in a time-dependent manner. Cell cycle studies revealed that NS
depletion resulted in G1 cell cycle arrest at short times of
transfection (24 h) followed with apoptosis at longer times (48 and 72 h), suggest that post-G1 arrest apoptosis is
occurred in K562 cells.
Conclusion: Overall, these results point to essential
role of NS in K562 cells, thus, this gene might be considered as a
promising target for treatment of CML.