1
|
Yang Y, Li Y, Yuan H, Liu X, Ren Y, Gao C, Jiao T, Cai Y, Zhao S. Characterization of circRNA–miRNA–mRNA networks regulating oxygen utilization in type II alveolar epithelial cells of Tibetan pigs. Front Mol Biosci 2022; 9:854250. [PMID: 36213124 PMCID: PMC9532862 DOI: 10.3389/fmolb.2022.854250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 08/30/2022] [Indexed: 11/13/2022] Open
Abstract
Understanding the signaling pathway regulatory mechanisms in type II alveolar epithelial (ATII) cells, the progenitor cells responsible for proliferating and regenerating type I alveolar epithelial (ATI) and ATII cells, in Tibetan pigs is beneficial for exploring methods of preventing and repairing cellular damage during hypoxia. We simulated a hypoxic environment (2% O2) for culture ATII cells of Tibetan pigs and Landrace pigs, with cells cultured under normoxic conditions (21% O2) as a control group, and performed integrated analysis of circular RNA (circRNA)–microRNA (miRNA)–messenger RNA (mRNA) regulatory axes by whole-transcriptome sequencing. Functional enrichment analysis indicated that the source genes of the differential expressed circRNAs (DEcircRNAs) were primarily involved in cell proliferation, cellular processes, and cell killing. A series of DEcircRNAs were derived from inhibitors of apoptosis proteins and led to a key autonomous effect as modulators of cell repair in Tibetan pigs under hypoxia. The significant higher expression of COL5A1 in TL groups may inhibited apoptosis of ATII cells in Tibetan pigs under lower oxygen concentration, and may lead their better survive in the hypoxia environment. In addition, a competing endogenous RNA (ceRNA) network of functional interactions was constructed that included novel_circ_000898-ssc-miR-199a-5p-CAV1 and novel_circ_000898-ssc-miR-378-BMP2, based on the node genes ssc-miR-199a-5p and ssc-miR-378, which may regulate multiple miRNAs and mRNAs that mediate endoplasmic reticulum (ER) stress-induced apoptosis and inflammation and attenuate hypoxia-induced injury in ATII cells under hypoxic conditions. These results broaden our knowledge of circRNAs, miRNAs, and mRNAs associated with hypoxia and provide new insights into the hypoxic response of ATII cells in Tibetan pigs.
Collapse
Affiliation(s)
- Yanan Yang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Yongqing Li
- Xinjiang Academy of Animal Sciences, Ürümqi, Xinjiang, China
| | - Haonan Yuan
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Xuanbo Liu
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Yue Ren
- Academy of Agriculture and Animal Husbandry Sciences, Institute of Animal Husbandry and Veterinary Medicine, Lhasa, China
| | - Caixia Gao
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Ting Jiao
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
- College of Grassland Science, Gansu Agricultural University, Lanzhou, China
| | - Yuan Cai
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Shengguo Zhao
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
- *Correspondence: Shengguo Zhao,
| |
Collapse
|
2
|
Fennell EMJ, Aponte-Collazo LJ, Wynn JD, Drizyte-Miller K, Leung E, Greer YE, Graves PR, Iwanowicz AA, Ashamalla H, Holmuhamedov E, Lang H, Karanewsky DS, Der CJ, Houry WA, Lipkowitz S, Iwanowicz EJ, Graves LM. Characterization of TR-107, a novel chemical activator of the human mitochondrial protease ClpP. Pharmacol Res Perspect 2022; 10:e00993. [PMID: 35929764 PMCID: PMC9354705 DOI: 10.1002/prp2.993] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 06/03/2022] [Indexed: 11/25/2022] Open
Abstract
We recently described the identification of a new class of small‐molecule activators of the mitochondrial protease ClpP. These compounds synthesized by Madera Therapeutics showed increased potency of cancer growth inhibition over the related compound ONC201. In this study, we describe chemical optimization and characterization of the next generation of highly potent and selective small‐molecule ClpP activators (TR compounds) and demonstrate their efficacy against breast cancer models in vitro and in vivo. We selected one compound (TR‐107) with excellent potency, specificity, and drug‐like properties for further evaluation. TR‐107 showed ClpP‐dependent growth inhibition in the low nanomolar range that was equipotent to paclitaxel in triple‐negative breast cancer (TNBC) cell models. TR‐107 also reduced specific mitochondrial proteins, including OXPHOS and TCA cycle components, in a time‐, dose‐, and ClpP‐dependent manner. Seahorse XF analysis and glucose deprivation experiments confirmed the inactivation of OXPHOS and increased dependence on glycolysis following TR‐107 exposure. The pharmacokinetic properties of TR‐107 were compared with other known ClpP activators including ONC201 and ONC212. TR‐107 displayed excellent exposure and serum t1/2 after oral administration. Using human TNBC MDA‐MB‐231 xenografts, the antitumor response to TR‐107 was investigated. Oral administration of TR‐107 resulted in a reduction in tumor volume and extension of survival in the treated compared with vehicle control mice. ClpP activation in vivo was validated by immunoblotting for TFAM and other mitochondrial proteins. In summary, we describe the identification of highly potent new ClpP agonists with improved efficacy against TNBC, through targeted inactivation of OXPHOS and disruption of mitochondrial metabolism.
Collapse
Affiliation(s)
- Emily M J Fennell
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Lucas J Aponte-Collazo
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Joshua D Wynn
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Kristina Drizyte-Miller
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Elisa Leung
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Yoshimi Endo Greer
- Women's Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Paul R Graves
- Department of Radiation Oncology, New York Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York, USA
| | | | - Hani Ashamalla
- Department of Radiation Oncology, New York Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York, USA
| | - Ekhson Holmuhamedov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russian Federation
| | - Henk Lang
- Madera Therapeutics LLC, Chapel Hill, North Carolina, USA
| | | | - Channing J Der
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Walid A Houry
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.,Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Stanley Lipkowitz
- Women's Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | | | - Lee M Graves
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| |
Collapse
|
3
|
Zhong K, Chen D, Wu Z, Wang X, Pan B, Chen N, Zhong W. [Effect of small interfering RNA-mediated BIRC6 silencing on apoptosis and autophagy of renal cancer 786-O cells]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2020; 40:1651-1655. [PMID: 33243730 DOI: 10.12122/j.issn.1673-4254.2020.11.18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To study the expression of BIRC6 in renal cancer tissues and investigate the effect of BIRC6 silencing on apoptosis and autophagy of 786-O cells. METHODS Twenty surgical specimens of renal cancer tissues and adjacent renal tissues were collected from Meizhou People's Hospital between February, 2016 and December, 2018 for detection of BIRC6 protein expression using immunohistochemistry. Renal cancer 786-O cells were transfected with a control small interfering RNA (siRNA) or BIRC6 siRNA via lipofectamine 2000, and the changes in cell proliferation and apoptosis following 5-FU treatment were assessed using CCK8 assay and flow cytometry; the expressions of autophagy-related proteins Beclin and LC3A/B were detected by Western blotting. RESULTS The expression of BIRC6 protein was significantly higher in renal cancer tissues than in the adjacent renal tissues. Western blotting showed that siRNA-mediated silencing of BIRC6 significantly lowered the expression of BIRC6 in 786-O cells. In the cells with BIRC6 silencing, treatment with 12.5, 25, 50, 100 and 200 μg/mL 5-FU resulted in significantly higher proliferation inhibition rates than in the cells transfected with the control siRNA (P < 0.01). BIRC6 silencing also significantly increased the apoptosis rate of 786-O cells following 5-FU treatment (P < 0.01). The results of Western blotting showed that BIRC6 silencing significantly lowered the protein expressions of Beclin and LC3A/B in 786-O cells. CONCLUSIONS Interference of BIRC6 mediated by siRNA can inhibit autophagy and promote 5-FU-induced apoptosis to enhance the sensitivity of 786-O cells to 5-FU.
Collapse
Affiliation(s)
- Kaihua Zhong
- Department of Urology, Meizhou People's Hospital, Meizhou 514031, China
| | - Dong Chen
- Department of Urology, Sun Yat-sen Cancer Center, Guangzhou 510060, China
| | - Zhiming Wu
- Department of Urology, Sun Yat-sen Cancer Center, Guangzhou 510060, China
| | - Xiaohong Wang
- Department of Nephrology, Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, China
| | - Bin Pan
- Department of Urology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Nanhui Chen
- Department of Urology, Meizhou People's Hospital, Meizhou 514031, China
| | - Weifeng Zhong
- Department of Urology, Meizhou People's Hospital, Meizhou 514031, China.,Department of Urology, Sun Yat-sen Cancer Center, Guangzhou 510060, China
| |
Collapse
|
4
|
Sürmen MG, Sürmen S, Ali A, Musharraf SG, Emekli N. Phosphoproteomic strategies in cancer research: a minireview. Analyst 2020; 145:7125-7149. [PMID: 32996481 DOI: 10.1039/d0an00915f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Understanding the cellular processes is central to comprehend disease conditions and is also true for cancer research. Proteomic studies provide significant insight into cancer mechanisms and aid in the diagnosis and prognosis of the disease. Phosphoproteome is one of the most studied complements of the whole proteome given its importance in the understanding of cellular processes such as signaling and regulations. Over the last decade, several new methods have been developed for phosphoproteome analysis. A significant amount of these efforts pertains to cancer research. The current use of powerful analytical instruments in phosphoproteomic approaches has paved the way for deeper and sensitive investigations. However, these methods and techniques need further improvements to deal with challenges posed by the complexity of samples and scarcity of phosphoproteins in the whole proteome, throughput and reproducibility. This review aims to provide a comprehensive summary of the variety of steps used in phosphoproteomic methods applied in cancer research including the enrichment and fractionation strategies. This will allow researchers to evaluate and choose a better combination of steps for their phosphoproteome studies.
Collapse
Affiliation(s)
- Mustafa Gani Sürmen
- Department of Molecular Medicine, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - Saime Sürmen
- Department of Molecular Medicine, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - Arslan Ali
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
| | - Syed Ghulam Musharraf
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
| | - Nesrin Emekli
- Department of Medical Biochemistry, Faculty of Medicine, Istanbul Medipol University, Istanbul, Turkey
| |
Collapse
|
5
|
Li H, Huang J, Yu S, Lou Z. Long Non-Coding RNA DLEU1 Up-Regulates BIRC6 Expression by Competitively Sponging miR-381-3p to Promote Cisplatin Resistance in Nasopharyngeal Carcinoma. Onco Targets Ther 2020; 13:2037-2045. [PMID: 32214823 PMCID: PMC7082798 DOI: 10.2147/ott.s237456] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/15/2020] [Indexed: 12/24/2022] Open
Abstract
Background Cisplatin (DDP) resistance has become an obstacle to chemotherapy for nasopharyngeal carcinoma (NPC) patients. Recent evidences indicate that long noncoding RNAs (lncRNAs) are involved in tumorigenesis and chemoresistance. However, the potential role of lncRNAs in NPC progression remains largely unknown. Methods First, lncRNA expression profiling in NPC was performed via microarray analysis. To explore the involvement of DLEU1 in DDP resistance, loss-of-function experiments were employed in vitro and in vivo. Bioinformatics analysis, luciferase reporter assay, qRT-PCR, and Western blot assays were used to investigate the underlying mechanisms. Results Here, we identified 153 differentially expressed lncRNAs. Among them, DLEU1 was remarkably up-regulated in NPC tissues and associated with worse outcome. Knock-down of DLEU1 could sensitize NPC cells to DDP in vitro and in vivo. Further investigations revealed that DLEU1 positively regulated BIRC6 expression via its competing endogenous RNA (ceRNA) activity on miR-381-3p. We also observed that BIRC6 overexpression or miR-381-3p silence could significantly reverse DLEU1-dependent DDP resistance. Conclusion Our data suggest that DLEU1 acts as an oncogene to promote DDP resistance and BIRC6 expression in NPC through interacting with miR-381-3p, which may help to develop new strategy against NPC chemoresistance.
Collapse
Affiliation(s)
- Hangbo Li
- Department of Otolaryngology, Zhuji People's Hospital, Zhuji 311800, People's Republic of China
| | - Jia Huang
- Department of Otolaryngology, Zhuji People's Hospital, Zhuji 311800, People's Republic of China
| | - Sa Yu
- Department of Otolaryngology, Zhuji People's Hospital, Zhuji 311800, People's Republic of China
| | - Zhiping Lou
- Department of Otolaryngology, Zhuji People's Hospital, Zhuji 311800, People's Republic of China
| |
Collapse
|
6
|
Lyn regulates creatine uptake in an imatinib-resistant CML cell line. Biochim Biophys Acta Gen Subj 2019; 1864:129507. [PMID: 31881245 DOI: 10.1016/j.bbagen.2019.129507] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 12/06/2019] [Accepted: 12/22/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Imatinib mesylate (imatinib) is the first-line treatment for newly diagnosed chronic myeloid leukemia (CML) due to its remarkable hematologic and cytogenetic responses. We previously demonstrated that the imatinib-resistant CML cells (Myl-R) contained elevated Lyn activity and intracellular creatine pools compared to imatinib-sensitive Myl cells. METHODS Stable isotope metabolic labeling, media creatine depletion, and Na+/K+-ATPase inhibitor experiments were performed to investigate the origin of creatine pools in Myl-R cells. Inhibition and shRNA knockdown were performed to investigate the specific role of Lyn in regulating the Na+/K+-ATPase and creatine uptake. RESULTS Inhibition of the Na+/K+-ATPase pump (ouabain, digitoxin), depletion of extracellular creatine or inhibition of Lyn kinase (ponatinib, dasatinib), demonstrated that enhanced creatine accumulation in Myl-R cells was dependent on uptake from the growth media. Creatine uptake was independent of the Na+/creatine symporter (SLC6A8) expression or de novo synthesis. Western blot analyses showed that phosphorylation of the Na+/K+-ATPase on Tyr 10 (Y10), a known regulatory phosphorylation site, correlated with Lyn activity. Overexpression of Lyn in HEK293 cells increased Y10 phosphorylation (pY10) of the Na+/K+-ATPase, whereas Lyn inhibition or shRNA knockdown reduced Na+/K+-ATPase pY10 and decreased creatine accumulation in Myl-R cells. Consistent with enhanced uptake in Myl-R cells, cyclocreatine (Ccr), a cytotoxic creatine analog, caused significant loss of viability in Myl-R compared to Myl cells. CONCLUSIONS These data suggest that Lyn can affect creatine uptake through Lyn-dependent phosphorylation and regulation of the Na+/K+-ATPase pump activity. GENERAL SIGNIFICANCE These studies identify kinase regulation of the Na+/K+-ATPase as pivotal in regulating creatine uptake and energy metabolism in cells.
Collapse
|
7
|
Lu C, Sun X, Li N, Wang W, Kuang D, Tong P, Han Y, Dai J. CircRNAs in the tree shrew ( Tupaia belangeri) brain during postnatal development and aging. Aging (Albany NY) 2019; 10:833-852. [PMID: 29723158 PMCID: PMC5940110 DOI: 10.18632/aging.101437] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 04/23/2018] [Indexed: 12/13/2022]
Abstract
Circular RNAs (circRNAs) are a novel type of non-coding RNA expressed across different species and tissues. At present, little is known about the expression and function of circRNAs in the tree shrew brain. In this study, we used RNA-seq to identify 35,007 circRNAs in hippocampus and cerebellum samples from infant (aged 47-52 days), young (aged 15-18 months), and old (aged 78-86 months) tree shrews. We observed no significant changes in the total circRNA expression profiles in different brain regions over time. However, circRNA tended to be downregulated in the cerebellum over time. Real-time RT-PCR analysis verified the presence of circRNAs. KEGG analysis indicated the occurrence of ubiquitin-mediated proteolysis, the MAPK signaling pathway, phosphatidylinositol signaling system, long-term depression, the rap1 signaling pathway, and long-term potentiation in both brain regions. We also observed that 29,087 (83.1%) tree shrew circRNAs shared homology with human circRNAs. The competing endogenous RNA networks suggested novel_circRNA_007362 potential functions as a 24-miRNAs sponge to regulate UBE4B expression. Thus, we obtained comprehensive circRNA expression profiles in the tree shrew brain during postnatal development and aging, which might help to elucidate the functions of circRNAs during brain aging and in age-related diseases.
Collapse
Affiliation(s)
- CaiXia Lu
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China.,Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Kunming, China.,Yunnan Innovation Team of Standardization and Application Research in Tree Shrew, Kunming, China
| | - XiaoMei Sun
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China.,Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Kunming, China.,Yunnan Innovation Team of Standardization and Application Research in Tree Shrew, Kunming, China
| | - Na Li
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China.,Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Kunming, China
| | - WenGuang Wang
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China.,Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Kunming, China
| | - DeXuan Kuang
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - PinFen Tong
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China.,Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Kunming, China
| | - YuanYuan Han
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - JieJie Dai
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China.,Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Kunming, China.,Yunnan Innovation Team of Standardization and Application Research in Tree Shrew, Kunming, China
| |
Collapse
|
8
|
Graves PR, Aponte-Collazo LJ, Fennell EMJ, Graves AC, Hale AE, Dicheva N, Herring LE, Gilbert TSK, East MP, McDonald IM, Lockett MR, Ashamalla H, Moorman NJ, Karanewsky DS, Iwanowicz EJ, Holmuhamedov E, Graves LM. Mitochondrial Protease ClpP is a Target for the Anticancer Compounds ONC201 and Related Analogues. ACS Chem Biol 2019; 14:1020-1029. [PMID: 31021596 PMCID: PMC6528275 DOI: 10.1021/acschembio.9b00222] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
![]()
ONC201
is a first-in-class imipridone molecule currently in clinical
trials for the treatment of multiple cancers. Despite enormous clinical
potential, the mechanism of action is controversial. To investigate
the mechanism of ONC201 and identify compounds with improved potency,
we tested a series of novel ONC201 analogues (TR compounds) for effects
on cell viability and stress responses in breast and other cancer
models. The TR compounds were found to be ∼50–100 times
more potent at inhibiting cell proliferation and inducing the integrated
stress response protein ATF4 than ONC201. Using immobilized TR compounds,
we identified the human mitochondrial caseinolytic protease P (ClpP)
as a specific binding protein by mass spectrometry. Affinity chromatography/drug
competition assays showed that the TR compounds bound ClpP with ∼10-fold
higher affinity compared to ONC201. Importantly, we found that the
peptidase activity of recombinant ClpP was strongly activated by ONC201
and the TR compounds in a dose- and time-dependent manner with the
TR compounds displaying a ∼10–100 fold increase in potency
over ONC201. Finally, siRNA knockdown of ClpP in SUM159 cells reduced
the response to ONC201 and the TR compounds, including induction of
CHOP, loss of the mitochondrial proteins (TFAM, TUFM), and the cytostatic
effects of these compounds. Thus, we report that ClpP directly binds
ONC201 and the related TR compounds and is an important biological
target for this class of molecules. Moreover, these studies provide,
for the first time, a biochemical basis for the difference in efficacy
between ONC201 and the TR compounds.
Collapse
Affiliation(s)
- Paul R. Graves
- Department of Radiation Oncology, New York Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York 11215, United States
| | - Lucas J. Aponte-Collazo
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Emily M. J. Fennell
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Adam C. Graves
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Andrew E. Hale
- Department of Microbiology and Immunology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Nedyalka Dicheva
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Laura E. Herring
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Thomas S. K. Gilbert
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Michael P. East
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Ian M. McDonald
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Matthew R. Lockett
- Department of Chemistry and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Hani Ashamalla
- Department of Radiation Oncology, New York Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York 11215, United States
| | - Nathaniel J. Moorman
- Department of Microbiology and Immunology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | | | - Edwin J. Iwanowicz
- Madera Therapeutics LLC, Chapel Hill, North Carolina 27517, United States
| | - Ekhson Holmuhamedov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142292, Russian Federation
| | - Lee M. Graves
- Department of Pharmacology and the Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| |
Collapse
|
9
|
Meenakshi Sundaram DN, Jiang X, Brandwein JM, Valencia-Serna J, Remant KC, Uludağ H. Current outlook on drug resistance in chronic myeloid leukemia (CML) and potential therapeutic options. Drug Discov Today 2019; 24:1355-1369. [PMID: 31102734 DOI: 10.1016/j.drudis.2019.05.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 02/25/2019] [Accepted: 05/09/2019] [Indexed: 12/13/2022]
Abstract
Chronic myeloid leukemia cells are armed with several resistance mechanisms that can make current drugs ineffective. A better understanding of resistance mechanisms is yielding new approaches to management of the disease. Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm the hallmark of which, the breakpoint cluster region-Abelson (BCR-ABL) oncogene, has been the target of tyrosine kinase inhibitors (TKIs), which have significantly improved the survival of patients with CML. However, because of an increase in TKI resistance, it is becoming imperative to identify resistance mechanisms so that drug therapies can be better prescribed and new agents developed. In this review, we discuss the various BCR-ABL-dependent and -independent mechanisms of resistance observed in CML, and the range of therapeutic solutions available to overcome such resistance and to ultimately improve the survival of patients with CML.
Collapse
Affiliation(s)
| | - Xiaoyan Jiang
- Terry Fox Laboratory, British Columbia Cancer Agency and Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | | | - Juliana Valencia-Serna
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada
| | - K C Remant
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada
| | - Hasan Uludağ
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada; Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada; Department of Biomedical Engineering, University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
10
|
Wang Z, Fang Z, Lu R, Zhao H, Gong T, Liu D, Hong L, Ma J, Zhang M. MicroRNA-204 Potentiates the Sensitivity of Acute Myeloid Leukemia Cells to Arsenic Trioxide. Oncol Res 2019; 27:1035-1042. [PMID: 30982490 PMCID: PMC7848422 DOI: 10.3727/096504019x15528367532612] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Although arsenic trioxide (ATO) is a well-known antileukemic drug used for acute promyelocytic leukemia treatment, the development of ATO resistance is still a big challenge. We previously reported that microRNA-204 (miR-204) was involved in the regulation of acute myeloid leukemia (AML) cell apoptosis, but its role in chemoresistance is poorly understood. In the present study, we showed that miR-204 was significantly increased in AML cells after ATO treatment. Interestingly, the increased miR-204 level that was negatively correlated with ATO induced the decrease in cell viability and baculoviral inhibition of apoptosis protein repeat-containing 6 (BIRC6) expression. Overexpression of miR-204 potentiated ATO-induced AML cell growth inhibition and apoptosis. Furthermore, miR-204 directly targets to the 3′-UTR of BIRC6. Upregulation of miR-204 decreased BIRC6 luciferase activity and expression, which subsequently enhanced the expression of p53. Restoration of BIRC6 markedly reversed the effect of miR-204 on the regulation of AML cell sensitivity to ATO. Taken together, our study demonstrates that miR-204 decreases ATO chemoresistance in AML cells at least partially via promoting BIRC6/p53-mediated apoptosis. miR-204 represents a novel target of ATO, and upregulation of miR-204 may be a useful strategy to improve the efficacy of ATO in AML treatment.
Collapse
Affiliation(s)
- Zhiguo Wang
- Department of Hematology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shanxi Province, P.R. China
| | - Zehui Fang
- Department of Endocrinology, the 4th Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, P.R. China
| | - Runzhang Lu
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin Province, P.R. China
| | - Hongli Zhao
- Department of Endocrinology, the 4th Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, P.R. China
| | - Tiejun Gong
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin Province, P.R. China
| | - Dong Liu
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin Province, P.R. China
| | - Luojia Hong
- Department of Endocrinology, the 4th Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, P.R. China
| | - Jun Ma
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin Province, P.R. China
| | - Mei Zhang
- Department of Hematology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shanxi Province, P.R. China
| |
Collapse
|
11
|
Cann ML, Herring LE, Haar LL, Gilbert TSK, Goldfarb D, Richards KL, Graves LM, Lawrence DS. Dasatinib Is Preferentially Active in the Activated B-Cell Subtype of Diffuse Large B-Cell Lymphoma. J Proteome Res 2018; 18:522-534. [PMID: 30540191 DOI: 10.1021/acs.jproteome.8b00841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, and at least one-third of its patients relapse after treatment with the current chemotherapy regimen, R-CHOP. By gene-expression profiling, patients with DLBCL can be categorized into two clinically relevant subtypes: activated B-cell (ABC) and germinal center B-cell (GCB) DLBCL. Patients with the ABC subtype have a worse prognosis than those with GCB, and the subtype is defined by chronic, over-active signaling through the B-cell receptor and NF-κB pathways. We examined the effects of the Src family kinase (SFK) inhibitor dasatinib in a panel of ABC and GCB DLBCL cell lines and found that the former are much more sensitive to dasatinib than the latter. However, using multiplexed inhibitor bead coupled to mass spectrometry (MIB/MS) kinome profiling and Western blot analysis, we found that both subtypes display inhibition of the SFKs in response to dasatinib after both short- and long-term treatment. The MIB/MS analyses revealed that several cell-cycle kinases, including CDK4, CDK6, and the Aurora kinases, are down-regulated by dasatinib treatment in the ABC, but not in the GCB, subtype. The present findings have potential implications for the clinical use of dasatinib for the treatment of ABC DLBCL, either alone or in combination with other agents.
Collapse
Affiliation(s)
| | | | | | | | | | - Kristy L Richards
- Department of Biomedical Sciences , College of Veterinary Medicine, Cornell University , T8 004b Veterinary Research Tower, Box 17 , Ithaca , New York 14853 , United States
| | | | | |
Collapse
|
12
|
Wang Z, Luo H, Fang Z, Fan Y, Liu X, Zhang Y, Rui S, Chen Y, Hong L, Gao J, Zhang M. MiR-204 acts as a potential therapeutic target in acute myeloid leukemia by increasing BIRC6-mediated apoptosis. BMB Rep 2018; 51:444-449. [PMID: 29764561 PMCID: PMC6177501 DOI: 10.5483/bmbrep.2018.51.9.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Indexed: 01/09/2023] Open
Abstract
Acute myeloid leukemia (AML) is one of the most common hematological malignancies all around the world. MicroRNAs have been determined to contribute various cancers initiation and progression, including AML. Although microRNA-204 (miR-204) exerts anti-tumor effects in several kinds of cancers, its function in AML remains unknown. In the present study, we assessed miR-204 expression in AML blood samples and cell lines. We also investigated the effects of miR-204 on cellular function of AML cells and the underlying mechanisms of the action of miR-204. Our results showed that miR-204 expression was significantly downregulated in AML tissues and cell lines. In addition, overexpression of miR-204 induced growth inhibition and apoptosis in AML cells, including AML5, HL-60, Kasumi-1 and U937 cells. Cell cycle analysis further confirmed an augmentation in theapoptotic subG1 population by miR-204 overexpression. Mechanistically, baculoviral inhibition of apoptosis protein repeat containing 6 (BIRC6) was identified as a direct target of miR-204. Enforcing miR-204 expression increased the luciferase activity and expression of BIRC6, as well as p53 and Bax expression. Moreover, restoration of BIRC6 reversed the pro-apoptotic effects of miR-204 overexpression in AML cells. Taken together, this study demonstrates that miR-204 causes AML cell apoptosis by targeting BIRC6, suggesting miR-204 may play an anti-carcinogenic role in AML and function as a novel biomarker and therapeutic target for the treatment of this disease.
Collapse
Affiliation(s)
- Zhiguo Wang
- Department of Hematology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, Shanxi Province; Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin 150010, People's Republic of China
| | - Hong Luo
- Department of Hematology, the First Hospital of Qiqihar, Qiqihar 150001, People's Republic of China
| | - Zehui Fang
- Department of Endocrinology, the 4th Affiliated Hospital of Harbin Medical University, Harbin 161000, Heilongjiang Province, People's Republic of China
| | - Yanling Fan
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin 150010, People's Republic of China
| | - Xiaojuan Liu
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin 150010, People's Republic of China
| | - Yujing Zhang
- Department of Endocrinology, the 4th Affiliated Hospital of Harbin Medical University, Harbin 161000, Heilongjiang Province, People's Republic of China
| | - Shuping Rui
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin 150010, People's Republic of China
| | - Yafeng Chen
- Department of Bone Marrow Transplantation, Harbin Hematological Cancer Institute, Harbin the First Hospital, Harbin 150010, People's Republic of China
| | - Luojia Hong
- Department of Endocrinology, the 4th Affiliated Hospital of Harbin Medical University, Harbin 161000, Heilongjiang Province, People's Republic of China
| | - Jincheng Gao
- Department of Endocrinology, the 4th Affiliated Hospital of Harbin Medical University, Harbin 161000, Heilongjiang Province, People's Republic of China
| | - Mei Zhang
- 1Department of Hematology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, Shanxi Province, People's Republic of China
| |
Collapse
|
13
|
Krulikas LJ, McDonald IM, Lee B, Okumu DO, East MP, Gilbert TSK, Herring LE, Golitz BT, Wells CI, Axtman AD, Zuercher WJ, Willson TM, Kireev D, Yeh JJ, Johnson GL, Baines AT, Graves LM. Application of Integrated Drug Screening/Kinome Analysis to Identify Inhibitors of Gemcitabine-Resistant Pancreatic Cancer Cell Growth. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2018; 23:850-861. [PMID: 29742358 PMCID: PMC6102050 DOI: 10.1177/2472555218773045] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Continuous exposure of a pancreatic cancer cell line MIA PaCa-2 (MiaS) to gemcitabine resulted in the formation of a gemcitabine-resistant subline (MiaR). In an effort to discover kinase inhibitors that inhibited MiaR growth, MiaR cells were exposed to kinase inhibitors (PKIS-1 library) in a 384-well screening format. Three compounds (UNC10112721A, UNC10112652A, and UNC10112793A) were identified that inhibited the growth of MiaR cells by more than 50% (at 50 nM). Two compounds (UNC10112721A and UNC10112652A) were classified as cyclin-dependent kinase (CDK) inhibitors, whereas UNC10112793A was reported to be a PLK inhibitor. Dose-response experiments supported the efficacy of these compounds to inhibit growth and increase apoptosis in 2D cultures of these cells. However, only UNC10112721A significantly inhibited the growth of 3D spheroids composed of MiaR cells and GFP-tagged cancer-associated fibroblasts. Multiplexed inhibitor bead (MIB)-mass spectrometry (MS) kinome competition experiments identified CDK9, CLK1-4, DYRK1A, and CSNK1 as major kinase targets for UNC10112721A in MiaR cells. Another CDK9 inhibitor (CDK-IN-2) replicated the growth inhibitory effects of UNC10112721A, whereas inhibitors against the CLK, DYRK, or CSNK1 kinases had no effect. In summary, these studies describe a coordinated approach to discover novel kinase inhibitors, evaluate their efficacy in 3D models, and define their specificity against the kinome.
Collapse
Affiliation(s)
- Linas J. Krulikas
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Ian M. McDonald
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Benjamin Lee
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Denis O. Okumu
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Michael P. East
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Thomas S. K. Gilbert
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Laura E. Herring
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Brian T. Golitz
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | - Carrow I. Wells
- Structural Genomics Consortium, University of North Carolina at Chapel Hill, NC, USA
| | - Allison D. Axtman
- Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC, USA
| | - William J. Zuercher
- Structural Genomics Consortium, University of North Carolina at Chapel Hill, NC, USA
| | - Timothy M. Willson
- Structural Genomics Consortium, University of North Carolina at Chapel Hill, NC, USA
| | - Dmitri Kireev
- Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC, USA
| | - Jen Jen Yeh
- Lineberger Cancer Center, University of North Carolina at Chapel Hill, NC, USA
| | - Gary L. Johnson
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| | | | - Lee M. Graves
- Department of Pharmacology, University of North Carolina at Chapel Hill, NC, USA
| |
Collapse
|
14
|
Abstract
Inhibitor of apoptosis (IAP) family comprises a group of endogenous proteins that function as main regulators of caspase activity and cell death. They are considered the main culprits in evasion of apoptosis, which is a fundamental hallmark of carcinogenesis. Overexpression of IAP proteins has been documented in various solid and hematological malignancies, rendering them resistant to standard chemotherapeutics and radiation therapy and conferring poor prognosis. This observation has urged their exploitation as therapeutic targets in cancer with promising pre-clinical outcomes. This review describes the structural and functional features of IAP proteins to elucidate the mechanism of their anti-apoptotic activity. We also provide an update on patterns of IAP expression in different tumors, their impact on treatment response and prognosis, as well as the emerging investigational drugs targeting them. This aims at shedding the light on the advances in IAP targeting achieved to date, and encourage further development of clinically applicable therapeutic approaches.
Collapse
Affiliation(s)
- Mervat S Mohamed
- Department of Biochemistry, Faculty of Science, University of Tabuk, Tabuk, Kingdom of Saudi Arabia.
- Department of Chemistry, Biochemistry Speciality, Faculty of Science, Cairo University, Giza, Egypt.
- , Tabuk, Kingdom of Saudi Arabia.
| | - Mai K Bishr
- Department of Radiotherapy, Children's Cancer Hospital Egypt (CCHE), Cairo, Egypt
| | - Fahad M Almutairi
- Department of Biochemistry, Faculty of Science, University of Tabuk, Tabuk, Kingdom of Saudi Arabia
| | - Ayat G Ali
- Department of Biochemistry, El Sahel Teaching Hospital, Cairo, Egypt
| |
Collapse
|
15
|
Hua JY, Zhou XH, Ouyang ST, Wu YB. [Effect of bortezomib in inducing apoptosis of imatinib-resistant K562 cells and the mechanism]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:1136-1139. [PMID: 28801299 PMCID: PMC6765724 DOI: 10.3969/j.issn.1673-4254.2017.08.23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To investigate the effect of bortezomib in inducing apoptosis in imatinib-resistant K562 (K562R) cells and its possible mechanism. METHODS K562 cells were cultured in gradient concentrations of imatinib for several months to generate imatinib-resistant K562 cells. The viability of K562R cells treated with bortezomib was measured using CCK-8 cell proliferation assay, and the cell apoptosis was analyzed by flow cytometry with annexin V/PI dual staining. Western blotting was used to detect the protein expressions of Mcl-1,Bcl-2 and Bcr/Abl. RESULTS K562R cell line was successfully established, which showed 31.8 folds of imatinib resistance compared with the na?ve cells. Bortezomib treatment produced dose- and time-dependent inhibitory effect on the proliferation of both K562 cells and K562R cells and dose-dependently induced apoptosis in K562R cells. Combination of bortezomib with imatinib significantly enhanced the apoptosis of the cells. Western blotting showed that bortezomib treatment dose-dependently decreased the protein levels of both Mcl-1and Bcr/Abl in K562R cells without affecting bcl-2 protein expression. CONCLUSION Bortezomib can inhibit the proliferation of K562R cells and induce cell apoptosis possibly by down-regulating Mcl-1 and Bcr/Abl expression and enhancing Mcl-1 cleavage.
Collapse
Affiliation(s)
- Jia-Ye Hua
- Department of Hematology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, China. E-mail:
| | | | | | | |
Collapse
|
16
|
Hua JY, Zhou XH, Ouyang ST, Wu YB. [Effect of bortezomib in inducing apoptosis of imatinib-resistant K562 cells and the mechanism]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:1136-1139. [PMID: 28801299 PMCID: PMC6765724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Indexed: 07/30/2024]
Abstract
OBJECTIVE To investigate the effect of bortezomib in inducing apoptosis in imatinib-resistant K562 (K562R) cells and its possible mechanism. METHODS K562 cells were cultured in gradient concentrations of imatinib for several months to generate imatinib-resistant K562 cells. The viability of K562R cells treated with bortezomib was measured using CCK-8 cell proliferation assay, and the cell apoptosis was analyzed by flow cytometry with annexin V/PI dual staining. Western blotting was used to detect the protein expressions of Mcl-1,Bcl-2 and Bcr/Abl. RESULTS K562R cell line was successfully established, which showed 31.8 folds of imatinib resistance compared with the na?ve cells. Bortezomib treatment produced dose- and time-dependent inhibitory effect on the proliferation of both K562 cells and K562R cells and dose-dependently induced apoptosis in K562R cells. Combination of bortezomib with imatinib significantly enhanced the apoptosis of the cells. Western blotting showed that bortezomib treatment dose-dependently decreased the protein levels of both Mcl-1and Bcr/Abl in K562R cells without affecting bcl-2 protein expression. CONCLUSION Bortezomib can inhibit the proliferation of K562R cells and induce cell apoptosis possibly by down-regulating Mcl-1 and Bcr/Abl expression and enhancing Mcl-1 cleavage.
Collapse
Affiliation(s)
- Jia-Ye Hua
- Department of Hematology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, China. E-mail:
| | | | | | | |
Collapse
|