NEK6 gene silencing using siRNA for overcome multidrug resistance in chronic myeloid leukemia cells

Abstract

Tumor cells become resistant to structurally or functionally unrelated chemotherapeutics which is called multidrug resistance (MDR). There are several mechanisms including the impairment of apoptotic pathway resulting in MDR development. NEK6 is a member of NIMA-related kinase family and it is an important mitotic kinase for proper cell cycle progression. Recent studies showed that NEK6 gene expression, protein level, and its kinase activity are increased in variety of cancer cells. We aimed to search the involvement of NEK6 in multidrug resistance and apoptosis in chronic myeloid leukemia. The expression levels of NEK6 and some of the apoptotic pathway genes such as BAX, BCL-2 and SURVIVIN were determined in sensitive and drug resistant subtypes of K652 chronic myeloid leukemia cell lines by RT-PCR method. siRNA silencing studies were performed to examine the effect of expression of NEK6 on apoptotic behavior in parental K-562 cell line. Cell viability assay was performed by XTT method in order to investigate whether NEK6 silencing leads to resistance in parental K-562 cells. NEK6 expression is significantly reduced in imatinib resistant K562 cells. After NEK6 gene is silenced by specific siRNA in parental K562 cell line, the expression levels of some apoptotic genes, such as BAX and SURVIVIN were found similar to drug resistant K562 cells. NEK6 may have potential role in imatinib resistance which may be through apoptotic pathway in chronic myeloid leukemia.

Keywords

• Chronic myeloid leukemia
• K562 cell line
• multidrug resistance
• Nek6
• apoptosis
• siRNA

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