1
|
de la Peña JB, Chase R, Kunder N, Smith PR, Lou TF, Stanowick A, Suresh P, Shukla T, Butcher SE, Price TJ, Campbell ZT. Inhibition of Nonsense-Mediated Decay Induces Nociceptive Sensitization through Activation of the Integrated Stress Response. J Neurosci 2023; 43:2921-2933. [PMID: 36894318 PMCID: PMC10124962 DOI: 10.1523/jneurosci.1604-22.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 02/20/2023] [Accepted: 03/01/2023] [Indexed: 03/11/2023] Open
Abstract
RNA stability is meticulously controlled. Here, we sought to determine whether an essential post-transcriptional regulatory mechanism plays a role in pain. Nonsense-mediated decay (NMD) safeguards against translation of mRNAs that harbor premature termination codons and controls the stability of ∼10% of typical protein-coding mRNAs. It hinges on the activity of the conserved kinase SMG1. Both SMG1 and its target, UPF1, are expressed in murine DRG sensory neurons. SMG1 protein is present in both the DRG and sciatic nerve. Using high-throughput sequencing, we examined changes in mRNA abundance following inhibition of SMG1. We confirmed multiple NMD stability targets in sensory neurons, including ATF4. ATF4 is preferentially translated during the integrated stress response (ISR). This led us to ask whether suspension of NMD induces the ISR. Inhibition of NMD increased eIF2-α phosphorylation and reduced the abundance of the eIF2-α phosphatase constitutive repressor of eIF2-α phosphorylation. Finally, we examined the effects of SMG1 inhibition on pain-associated behaviors. Peripheral inhibition of SMG1 results in mechanical hypersensitivity in males and females that persists for several days and priming to a subthreshold dose of PGE2. Priming was fully rescued by a small-molecule inhibitor of the ISR. Collectively, our results indicate that suspension of NMD promotes pain through stimulation of the ISR.SIGNIFICANCE STATEMENT Nociceptors undergo long-lived changes in their plasticity which may contribute to chronic pain. Translational regulation has emerged as a dominant mechanism in pain. Here, we investigate the role of a major pathway of RNA surveillance called nonsense-mediated decay (NMD). Modulation of NMD is potentially beneficial for a broad array of diseases caused by frameshift or nonsense mutations. Our results suggest that inhibition of the rate-limiting step of NMD drives behaviors associated with pain through activation of the ISR. This work reveals complex interconnectivity between RNA stability and translational regulation and suggests an important consideration in harnessing the salubrious benefits of NMD disruption.
Collapse
Affiliation(s)
- June Bryan de la Peña
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin 53792
| | - Rebecca Chase
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Nikesh Kunder
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Patrick R Smith
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin 53792
| | - Tzu-Fang Lou
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Alexander Stanowick
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Prarthana Suresh
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Tarjani Shukla
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin 53792
| | - Samuel E Butcher
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53792
| | - Theodore J Price
- Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, Texas 75080
- Department of Neuroscience, University of Texas at Dallas, Richardson, Texas 75080
| | - Zachary T Campbell
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, Wisconsin 53792
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53792
| |
Collapse
|
2
|
Kunder N, de la Peña JB, Lou TF, Chase R, Suresh P, Lawson J, Shukla T, Black B, Campbell ZT. The RNA-Binding Protein HuR Is Integral to the Function of Nociceptors in Mice and Humans. J Neurosci 2022; 42:9129-9141. [PMID: 36270801 PMCID: PMC9761683 DOI: 10.1523/jneurosci.1630-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/04/2022] [Accepted: 10/12/2022] [Indexed: 11/06/2022] Open
Abstract
HuR is an RNA-binding protein implicated in RNA processing, stability, and translation. Previously, we examined protein synthesis in dorsal root ganglion (DRG) neurons treated with inflammatory mediators using ribosome profiling. We found that the HuR consensus binding element was enriched in transcripts with elevated translation. HuR is expressed in the soma of nociceptors and their axons. Pharmacologic inhibition of HuR with the small molecule CMLD-2 reduced the activity of mouse and human sensory neurons. Peripheral administration of CMLD-2 in the paw or genetic elimination of HuR from sensory neurons diminished behavioral responses associated with NGF- and IL-6-induced allodynia in male and female mice. Genetic disruption of HuR altered the proximity of mRNA decay factors near a key neurotrophic factor (TrkA). Collectively, the data suggest that HuR is required for local control of mRNA stability and reveals a new biological function for a broadly conserved post-transcriptional regulatory factor.SIGNIFICANCE STATEMENT Nociceptors undergo long-lived changes in excitability, which may contribute to chronic pain. Noxious cues that promote pain lead to rapid induction of protein synthesis. The underlying mechanisms that confer specificity to mRNA control in nociceptors are unclear. Here, we identify a conserved RNA-binding protein called HuR as a key regulatory factor in sensory neurons. Using a combination of genetics and pharmacology, we demonstrate that HuR is required for signaling in nociceptors. In doing so, we report an important mechanism of mRNA control in sensory neurons that ensures appropriate nociceptive responses to inflammatory mediators.
Collapse
Affiliation(s)
- Nikesh Kunder
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - June Bryan de la Peña
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53792
| | - Tzu-Fang Lou
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Rebecca Chase
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Prarthana Suresh
- Department of Biological Sciences, University of Texas at Dallas, Richardson, Texas 75080
| | - Jennifer Lawson
- Department of Biomedical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts 01854
| | - Tarjani Shukla
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53792
| | - Bryan Black
- Department of Biomedical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts 01854
| | - Zachary T Campbell
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53792
- Department of Biomolecular Chemistry, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53792
| |
Collapse
|
3
|
Smith PR, Loerch S, Kunder N, Stanowick AD, Lou TF, Campbell ZT. Functionally distinct roles for eEF2K in the control of ribosome availability and p-body abundance. Nat Commun 2021; 12:6789. [PMID: 34815424 PMCID: PMC8611098 DOI: 10.1038/s41467-021-27160-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 11/07/2021] [Indexed: 11/09/2022] Open
Abstract
Processing bodies (p-bodies) are a prototypical phase-separated RNA-containing granule. Their abundance is highly dynamic and has been linked to translation. Yet, the molecular mechanisms responsible for coordinate control of the two processes are unclear. Here, we uncover key roles for eEF2 kinase (eEF2K) in the control of ribosome availability and p-body abundance. eEF2K acts on a sole known substrate, eEF2, to inhibit translation. We find that the eEF2K agonist nelfinavir abolishes p-bodies in sensory neurons and impairs translation. To probe the latter, we used cryo-electron microscopy. Nelfinavir stabilizes vacant 80S ribosomes. They contain SERBP1 in place of mRNA and eEF2 in the acceptor site. Phosphorylated eEF2 associates with inactive ribosomes that resist splitting in vitro. Collectively, the data suggest that eEF2K defines a population of inactive ribosomes resistant to recycling and protected from degradation. Thus, eEF2K activity is central to both p-body abundance and ribosome availability in sensory neurons.
Collapse
Affiliation(s)
- Patrick R. Smith
- grid.267323.10000 0001 2151 7939The University of Texas at Dallas, Department of Biological Sciences, Richardson, TX USA
| | - Sarah Loerch
- grid.443970.dJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA USA ,grid.205975.c0000 0001 0740 6917University of California, Santa Cruz, Department of Chemistry and Biochemistry, Santa Cruz, CA USA
| | - Nikesh Kunder
- grid.267323.10000 0001 2151 7939The University of Texas at Dallas, Department of Biological Sciences, Richardson, TX USA
| | - Alexander D. Stanowick
- grid.267323.10000 0001 2151 7939The University of Texas at Dallas, Department of Biological Sciences, Richardson, TX USA
| | - Tzu-Fang Lou
- grid.267323.10000 0001 2151 7939The University of Texas at Dallas, Department of Biological Sciences, Richardson, TX USA
| | - Zachary T. Campbell
- grid.267323.10000 0001 2151 7939The University of Texas at Dallas, Department of Biological Sciences, Richardson, TX USA ,grid.267323.10000 0001 2151 7939The Center for Advanced Pain Studies (CAPS), University of Texas at Dallas, Richardson, TX USA
| |
Collapse
|
4
|
Bryan de la Peña J, Kunder N, Lou TF, Chase R, Stanowick A, Barragan-Iglesias P, Pancrazio JJ, Campbell ZT. A Role for Translational Regulation by S6 Kinase and a Downstream Target in Inflammatory Pain. Br J Pharmacol 2021; 178:4675-4690. [PMID: 34355805 DOI: 10.1111/bph.15646] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Translational controls pervade neurobiology. Nociceptors play an integral role in the detection and propagation of pain signals. Nociceptors can undergo persistent changes in their intrinsic excitability. Pharmacologic disruption of nascent protein synthesis diminishes acute and chronic forms of pain-associated behaviors. Yet, the targets of translational controls that facilitate plasticity in nociceptors are unclear. EXPERIMENTAL APPROACH We used ribosome profiling to probe the translational landscape in DRG neurons after treatment of the inflammatory mediators NGF and IL-6. We validated the expression dynamics of c-Fos using immunoblotting and immunohistochemistry. Given that inflammation is known to stimulate mTOR signaling, we reasoned that downstream factors (e.g., ribosomal protein S6 kinase 1, S6K1) might control c-Fos levels. We utilized small-molecule inhibitors of S6K1 (DG2) or c-Fos (T-5224) to probe their effects on nociceptor activity in vitro using multi-electrode arrays (MEAs) and pain behavior in vivo using a hyperalgesic priming model. KEY RESULTS We demonstrate that c-Fos is expressed in sensory neurons. Inflammatory mediators that promote pain in both humans and rodents promote c-Fos translation. We demonstrate that the mTOR effector S6K1 is essential for c-Fos biosynthesis. Inhibition of S6K1 or c-Fos with small molecules diminish mechanical and thermal hypersensitivity in response to inflammatory cues. Additionally, both inhibitors reduce evoked nociceptor activity. CONCLUSION Our data reveal a novel role of S6K1 in modulating rapid response to inflammatory mediators, with c-Fos being one key downstream target. Targeting the S6 kinase pathway or c-Fos is an exciting new avenue for pain-modulating compounds.
Collapse
Affiliation(s)
- June Bryan de la Peña
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Nikesh Kunder
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Tzu-Fang Lou
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Rebecca Chase
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Alexander Stanowick
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Paulino Barragan-Iglesias
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, USA.,Department of Physiology and Pharmacology, Center for Basic Sciences, Autonomous University of Aguascalientes, Aguascalientes, Mexico
| | - Joseph J Pancrazio
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA.,Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - Zachary T Campbell
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA.,Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA.,Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| |
Collapse
|
5
|
Barragan-Iglesias P, Kunder N, Wanghzou A, Black B, Ray PR, Lou TF, de la Peña JB, Atmaramani R, Shukla T, Pancrazio JJ, Price TJ, Campbell ZT. A peptide encoded within a 5' untranslated region promotes pain sensitization in mice. Pain 2021; 162:1864-1875. [PMID: 33449506 PMCID: PMC8119312 DOI: 10.1097/j.pain.0000000000002191] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/04/2021] [Indexed: 12/23/2022]
Abstract
ABSTRACT Translational regulation permeates neuronal function. Nociceptors are sensory neurons responsible for the detection of harmful stimuli. Changes in their activity, termed plasticity, are intimately linked to the persistence of pain. Although inhibitors of protein synthesis robustly attenuate pain-associated behavior, the underlying targets that support plasticity are largely unknown. Here, we examine the contribution of protein synthesis in regions of RNA annotated as noncoding. Based on analyses of previously reported ribosome profiling data, we provide evidence for widespread translation in noncoding transcripts and regulatory regions of mRNAs. We identify an increase in ribosome occupancy in the 5' untranslated regions of the calcitonin gene-related peptide (CGRP/Calca). We validate the existence of an upstream open reading frame (uORF) using a series of reporter assays. Fusion of the uORF to a luciferase reporter revealed active translation in dorsal root ganglion neurons after nucleofection. Injection of the peptide corresponding to the calcitonin gene-related peptide-encoded uORF resulted in pain-associated behavioral responses in vivo and nociceptor sensitization in vitro. An inhibitor of heterotrimeric G protein signaling blocks both effects. Collectively, the data suggest pervasive translation in regions of the transcriptome annotated as noncoding in dorsal root ganglion neurons and identify a specific uORF-encoded peptide that promotes pain sensitization through GPCR signaling.
Collapse
Affiliation(s)
- Paulino Barragan-Iglesias
- University of Texas at Dallas, School of Behavioral and
Brain Sciences, Richardson, TX, 75080, USA
- Department of Physiology and Pharmacology, Center for Basic
Sciences, Autonomous University of Aguascalientes, Aguascalientes, 20130,
Mexico
| | - Nikesh Kunder
- University of Texas at Dallas, Department of Biological
Sciences, Richardson, TX, 75080, USA
| | - Andi Wanghzou
- University of Texas at Dallas, School of Behavioral and
Brain Sciences, Richardson, TX, 75080, USA
| | - Bryan Black
- University of Texas at Dallas, Department of
Bioengineering, Richardson, TX, 75080, USA
| | - Pradipta R. Ray
- University of Texas at Dallas, School of Behavioral and
Brain Sciences, Richardson, TX, 75080, USA
| | - Tzu-Fang Lou
- University of Texas at Dallas, Department of Biological
Sciences, Richardson, TX, 75080, USA
| | - June Bryan de la Peña
- University of Texas at Dallas, Department of Biological
Sciences, Richardson, TX, 75080, USA
| | - Rahul Atmaramani
- University of Texas at Dallas, Department of
Bioengineering, Richardson, TX, 75080, USA
| | - Tarjani Shukla
- University of Texas at Dallas, Department of Biological
Sciences, Richardson, TX, 75080, USA
| | - Joseph J. Pancrazio
- University of Texas at Dallas, Department of
Bioengineering, Richardson, TX, 75080, USA
- Center for Advanced Pain Studies, University of Texas at
Dallas, Richardson, TX, 75080, USA
| | - Theodore J. Price
- University of Texas at Dallas, School of Behavioral and
Brain Sciences, Richardson, TX, 75080, USA
- Center for Advanced Pain Studies, University of Texas at
Dallas, Richardson, TX, 75080, USA
| | - Zachary T. Campbell
- University of Texas at Dallas, Department of Biological
Sciences, Richardson, TX, 75080, USA
- Center for Advanced Pain Studies, University of Texas at
Dallas, Richardson, TX, 75080, USA
| |
Collapse
|
6
|
Tembhare PR, Ghogale S, Ghatwai N, Badrinath Y, Kunder N, Patkar NV, Bibi AR, Chatterjee G, Arora B, Narula G, Banawali S, Deshpande N, Amare P, Gujral S, Subramanian PG. Evaluation of new markers for minimal residual disease monitoring in B-cell precursor acute lymphoblastic leukemia: CD73 and CD86 are the most relevant new markers to increase the efficacy of MRD 2016; 00B: 000-000. Cytometry B Clin Cytom 2016; 94:100-111. [PMID: 27718302 DOI: 10.1002/cyto.b.21486] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 10/02/2016] [Accepted: 10/05/2016] [Indexed: 01/17/2023]
Abstract
BACKGROUND Multiparametric flow cytometry (MFC) is a popular technique for minimal residual disease (MRD) analysis. However, its applicability is still limited to 90% of B-cell precursor acute lymphoblastic leukemia (BCPALL) due to two major issues, i.e. a proportion of cases do not express adequate leukemia associated immunophenotype (LAIPs) with currently used markers and drug-induced antigen modulation. Hence, the incorporation of additional reliable markers is required for the further improvement of MFC-based MRD evaluation. We studied the utility of new markers in improvising MFC-based MRD detection in BCPALL. METHODS Expression-patterns of six new markers, i.e. CD24, CD44, CD72, CD73, CD86, and CD200 were studied in leukemic-blasts from ninety childhood BCPALL patients and in hematogones from 20 uninvolved staging bone marrow (BM) and ten postinduction non-BCPALL BM samples using eight-color MFC. The utility of these new markers in the day 35 postinduction MRD evaluation was determined. RESULTS Frequencies of LAIPs of CD73, CD86, CD72, CD44, CD200, and CD24 in diagnostic samples were 76.7, 56.7, 55.6, 50, 28.9, and 20%, respectively. Differential expression of all new markers was highly significant (P < 0.01) between early (CD10+ CD19+ CD34+) hematogones, late (CD10+ CD19+ CD34-) hematogones and BCPALL blasts except between early hematogones and BCPALL blasts for CD200 (P = 0.1). In MRD-positive samples, CD73 showed the maximum (83%) frequency of LAIP and CD86 showed the highest (100%) stability of aberrant expression. Inclusion of CD73 and CD86 increased the applicability of MFC-MRD assay to 98.9% MRD samples. CONCLUSION CD73 and CD86 are the most relevant markers to incorporate in the routine MRD evaluation of BCPALL. © 2016 International Clinical Cytometry Society.
Collapse
Affiliation(s)
- Prashant R Tembhare
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Sitaram Ghogale
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Nisha Ghatwai
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Yajamanam Badrinath
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Nikesh Kunder
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Nikhil V Patkar
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Asma R Bibi
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Gaurav Chatterjee
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Brijesh Arora
- Department of Pediatric Oncology, Tata Memorial Center, Main Building, Ground floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Gaurav Narula
- Department of Pediatric Oncology, Tata Memorial Center, Main Building, Ground floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Shripad Banawali
- Department of Pediatric Oncology, Tata Memorial Center, Main Building, Ground floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Nilesh Deshpande
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Prathibha Amare
- Department of Cancer Cytogenetics, Tata Memorial Center, Mumbaim, Room 726, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Sumeet Gujral
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| | - Papagudi G Subramanian
- Hematopathology Laboratory, Tata Memorial Center, Mumbai, Room 727, Hematopathology Laboratory, Annexe Building, 7th Floor, Tata Memorial Hospital, Parel, 400012, Mumbai, India
| |
Collapse
|
7
|
Tembhare P, Badrinath Y, Ghogale S, Patkar N, Dhole N, Dalavi P, Kunder N, Kumar A, Gujral S, Subramanian PG. A novel and easy FxCycle™ violet based flow cytometric method for simultaneous assessment of DNA ploidy and six-color immunophenotyping. Cytometry A 2015; 89:281-91. [PMID: 26671309 DOI: 10.1002/cyto.a.22803] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 09/07/2015] [Accepted: 11/13/2015] [Indexed: 01/19/2023]
Abstract
Abnormal DNA ploidy is a valuable prognostic factor in many neoplasms, especially in hematological neoplasms like B-cell acute lymphoblastic leukemia (B-ALL) and multiple myeloma (MM). Current methods of flow-cytometric (FC) DNA-ploidy evaluation are either technically difficult or limited to three- to four-color immunophenotyping and hence, challenging to evaluate DNA-ploidy in minute tumor population with background rich of its normal counterpart cells and other hematopoietic cells. We standardized a novel sensitive and easy method of simultaneous evaluation of six- to seven-color immunophenotyping and DNA-ploidy using a dye-FxCycle Violet (FCV). Linearity, resolution, and coefficient of variation (CV) for FCV were studied using chicken erythrocyte nuclei. Ploidy results of FCV were compared with Propidium iodide (PI) in 20 samples and intra-assay variation for FCV was studied. Using this six-color immunophenotyping & FCV-protocol DNA-ploidy was determined in bone-marrow samples from 124 B-ALL & 50 MM patients. Dilution experiment was also conducted to determine the sensitivity in detection of aneuploidy in minute tumor population. FCV revealed high linearity and resolution in 450/50 channel. On comparison with PI, CV of Go/G1-peak with FCV (mean-CV 4.1%) was slightly higher than PI (mean-CV 2.9%) but had complete agreement in ploidy results. Dilution experiment showed that aneuploidy could be accurately detected up to the limit of 0.01% tumor cells. Intra-assay variation was very low with CV of 0.005%. In B-ALL, hypodiploidy was noted in 4%, hyperdiploidy in 24%, near-hyperdiploidy in 13% and remaining 59% were diploid. In MM, hypodiploidy was in 2%, hyperdiploidy in 58%, near-hyperdiploidy in 8% and remaining 30% were diploid. FCV-based DNA-ploidy method is a sensitive and easy method for simultaneous evaluation of six-color immunophenotyping and DNA analysis. It is useful in DNA-ploidy evaluation of minute tumor population in cases like minimal residual disease and MM precursor conditions.
Collapse
Affiliation(s)
- Prashant Tembhare
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Yajamanam Badrinath
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Sitaram Ghogale
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Nikhil Patkar
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Nilesh Dhole
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Pooja Dalavi
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Nikesh Kunder
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Ashok Kumar
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - Sumeet Gujral
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| | - P G Subramanian
- Hematopathology Laboratory, Tata Memorial Center Hospital, Parel, Mumbai, 400012, India
| |
Collapse
|