Downregulation of Smad4 expression confers chemoresistance against imatinib mesylate to chronic myeloid leukemia K562 cells

Background: Chronic myeloid leukemia (CML), is characterized by a reciprocal translocation t(9;22) and forms the BCR/ABL1 fusion gene, which is called the Philadelphia chromosome. The therapeutic targets for CML patients which are mediated with BCR/ABL1 oncogenic are tyrosine kinase inhibitors such as imatinib, dasatinib, and nilotinib. The latter two of which have been approved for the treatment of imatinib-resistant or intolerance CML patients. Mitotic catastrophe (MC) is one of the non-apoptotic mechanisms which frequently initiated in types of cancer cells in response to anti-cancer therapies; pharmacological inhibitors of G2 checkpoint members or genetic suppression of PLK1, PLK2, ATR, ATM, CHK1, and CHK2 can trigger DNA-damage-stimulated mitotic catastrophe. PLK1, AURKA/B anomalously expressed in CML cells, that phosphorylation and activation of PLK1 occur by AURKB at centromeres and kinetochores. Objective: The purpose of this study was to investigate the effect of dasatinib on the expression of genes in MC and apoptosis pathways in K562 cells. Methods: Total RNA was isolated from K-562 cells treated with the IC50 value of dasatinib and untreated cells as a control group. The expression of MC and apoptosis-related genes were analyzed by the qRT-PCR system. Results: The array-data demonstrated that dasatinib-treated K562 cells significantly caused the decrease of several genes (AURKA, AURKB, PLK, CHEK1, MYC, XPC, BCL2, and XRCC2). Conclusion: The evidence supply a basis to support clinical researches for the suppression of oncogenes such as PLKs with AURKs in the treatment of types of cancer especially chronic myeloid leukemia.

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EXPRESS: Characterization of Drug Resistance in Chronic Myeloid Leukemia Cells Based on Laser Tweezers Raman Spectroscopy

Applied Spectroscopy ◽

10.1177/00037028211024581 ◽

2021 ◽

pp. 000370282110245

Author(s):

Qian Zhang ◽

Minlu Ye ◽

Lingyan Wang ◽

Dongmei Jiang ◽

Shuting Yao ◽

...

Keyword(s):

Raman Spectroscopy ◽

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

K562 Cells ◽

Laser Tweezers ◽

Label Free ◽

Multivariate Statistical ◽

Analytical Strategy ◽

Specificity And Sensitivity ◽

Acid Protein

Multidrug resistance (MDR) is highly associated with poor prognosis of chronic myeloid leukemia (CML). This work aims to explore whether the laser tweezers Raman spectroscopy (LTRS) could be practical in separating adriamycin (ADR) resistance CML cells K562/ADR from its parental cells K562, and to explore the potential mechanisms. Detection of LTRS initially reflected the spectral differences caused by chemoresistance including bands assigned to carbohydrates, amino acid, protein, lipids and nucleic acid. In addition, principal components analysis (PCA) as well as the classification and regression trees (CRT) algorithms showed that the specificity and sensitivity were above 90%. Moreover, the band data-based CRT model and receiver operating characteristic (ROC) curve further determined some important bands and band intensity ratios to be reliable indexes in discriminating K562 chemoresistance status. Finally, we highlighted three metabolism pathways correlated with chemoresistance. This work demonstrates that the label-free LTRS analysis combined with multivariate statistical analyses have great potential to be a novel analytical strategy at the single-cell level for rapid evaluation the chemoresistance status of K562 cells.

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Secondary Structural Model of MALAT1 Becomes Unstructured in Chronic Myeloid Leukemia and Undergoes Structural Rearrangement in Cervical Cancer

Non-Coding RNA ◽

10.3390/ncrna7010006 ◽

2021 ◽

Vol 7 (1) ◽

pp. 6

Author(s):

Matthew C. Wang ◽

Phillip J. McCown ◽

Grace E. Schiefelbein ◽

Jessica A. Brown

Keyword(s):

Cervical Cancer ◽

Chronic Myeloid Leukemia ◽

Hela Cells ◽

Binding Sites ◽

Myeloid Leukemia ◽

Structural Changes ◽

Structural Model ◽

Dimethyl Sulfate ◽

K562 Cells ◽

Cancer Types

Long noncoding RNAs (lncRNAs) influence cellular function through binding events that often depend on the lncRNA secondary structure. One such lncRNA, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), is upregulated in many cancer types and has a myriad of protein- and miRNA-binding sites. Recently, a secondary structural model of MALAT1 in noncancerous cells was proposed to form 194 hairpins and 13 pseudoknots. That study postulated that, in cancer cells, the MALAT1 structure likely varies, thereby influencing cancer progression. This work analyzes how that structural model is expected to change in K562 cells, which originated from a patient with chronic myeloid leukemia (CML), and in HeLa cells, which originated from a patient with cervical cancer. Dimethyl sulfate-sequencing (DMS-Seq) data from K562 cells and psoralen analysis of RNA interactions and structure (PARIS) data from HeLa cells were compared to the working structural model of MALAT1 in noncancerous cells to identify sites that likely undergo structural alterations. MALAT1 in K562 cells is predicted to become more unstructured, with almost 60% of examined hairpins in noncancerous cells losing at least half of their base pairings. Conversely, MALAT1 in HeLa cells is predicted to largely maintain its structure, undergoing 18 novel structural rearrangements. Moreover, 50 validated miRNA-binding sites are affected by putative secondary structural changes in both cancer types, such as miR-217 in K562 cells and miR-20a in HeLa cells. Structural changes unique to K562 cells and HeLa cells provide new mechanistic leads into how the structure of MALAT1 may mediate cancer in a cell-type specific manner.

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Apoptosis Induced by Tanshinone IIA and Cryptotanshinone Is Mediated by Distinct JAK/STAT3/5 and SHP1/2 Signaling in Chronic Myeloid Leukemia K562 Cells

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/805639 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 19

Author(s):

Ji Hoon Jung ◽

Tae-Rin Kwon ◽

Soo-Jin Jeong ◽

Eun-Ok Kim ◽

Eun Jung Sohn ◽

...

Keyword(s):

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

Biological Effects ◽

K562 Cells ◽

Tanshinone Iia ◽

Anticancer Activities ◽

Caspase 9 ◽

Anticancer Effects ◽

Induced Apoptosis ◽

Better Than

Though tanshinone IIA and cryptotanshinone possess a variety of biological effects such as anti-inflammatory, antioxidative, antimetabolic, and anticancer effects, the precise molecular targets or pathways responsible for anticancer activities of tanshinone IIA and cryptotanshinone in chronic myeloid leukemia (CML) still remain unclear. In the present study, we investigated the effect of tanshinone IIA and cryptotanshinone on the Janus activated kinase (JAK)/signal transducer and activator of transcription (STAT) signaling during apoptotic process. We found that both tanshinone IIA and cryptotanshinone induced apoptosis by activation of caspase-9/3 and Sub-G1 accumulation in K562 cells. However, they have the distinct JAK/STAT pathway, in which tanshinone IIA inhibits JAK2/STAT5 signaling, whereas cryptotanshinone targets the JAK2/STAT3. In addition, tanshinone IIA enhanced the expression of both SHP-1 and -2, while cryptotanshinone regulated the expression of only SHP-1. Both tanshinone IIA and cryptotanshinone attenuated the expression of bcl-xL, survivin, and cyclin D1. Furthermore, tanshinone IIA augmented synergy with imatinib, a CML chemotherapeutic drug, better than cryptotanshinone in K562 cells. Overall, our findings suggest that the anticancer activity of tanshinone IIA and cryptotanshinone is mediated by the distinct the JAK/STAT3/5 and SHP1/2 signaling, and tanshinone IIA has the potential for combination therapy with imatinib in K562 CML cells.

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