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Srinivasalu V, Subramaniam N, Kumar N, Balasubramaniam D, Philip A, Susan A, Remesan Nair A, Prameela CG, Pushpaja K, Thankappan K, Jose W, Iyer S, Keechilat P. Do patients over 70 years with advanced head and neck squamous cell carcinoma tolerate curative intent concurrent chemo-radiation? Predictors of oncological outcomes. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx374.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Srinivasalu V, Subramaniam N, Balasubramaniam D, Kumar N, Murthy S, Susan A, Philip A, Thankappan K, Iyer S, Keechilat P. Tobacco exposure and adverse pathological features in oral cancer: Does age impact survival? Ann Oncol 2017. [DOI: 10.1093/annonc/mdx385.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Kaplan J, Gordon L, Infante J, Popat R, Rambaldi A, Madan S, Patel M, Gritti G, El-Sharkawi D, Chau I, Radford J, Perez De Oteyza J, Zinzani P, Iyer S, Faucette S, Sheldon-Waniga E, Stumpo K, Shou Y, Carpio C, Bosch F. TAK-659, AN INVESTIGATIONAL REVERSIBLE DUAL SYK/FLT-3 INHIBITOR, IN PATIENTS WITH LYMPHOMA: UPDATED RESULTS FROM DOSE-ESCALATION AND EXPANSION COHORTS OF a PHASE 1 STUDY. Hematol Oncol 2017. [DOI: 10.1002/hon.2437_60] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Pantelides NM, Young SS, Iyer S. The rectus abdominis muscle advancement flap as a salvage option for chest wall reconstruction. Ann R Coll Surg Engl 2017; 99:e142-e144. [PMID: 28462651 DOI: 10.1308/rcsann.2017.0044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We describe a previously unreported technique of advancing the rectus abdominis muscle superiorly, based on the deep inferior epigastric artery, to cover a lower anterior chest wall defect. This technique represents an important salvage option for chest wall reconstruction and affords a great deal of intra-operative flexibility.
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Pantelides NM, Young S, Iyer S. The dorsal distally based flap: a novel approach to the distal interphalangeal joint. J Hand Surg Eur Vol 2017; 42:428-429. [PMID: 26768220 DOI: 10.1177/1753193415625397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Krishnadas A, Subash P, Iyer S. Inverse planning in maxillomandibular reconstruction. Int J Oral Maxillofac Surg 2017. [DOI: 10.1016/j.ijom.2017.02.629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Young S, Murphy R, Iyer S. A rare case of a direct ocular contact burn to the right eye. Ann R Coll Surg Engl 2017; 99:e31-e33. [PMID: 27659381 PMCID: PMC5392806 DOI: 10.1308/rcsann.2016.0285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2016] [Indexed: 11/22/2022] Open
Abstract
Ocular thermal burns represent an oculoplastic emergency, with the potential for blindness owing to limbal ischaemia. We present a rare case of a 66-year-old man who sustained a direct thermal contact burn to the right eye.
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Purcell J, Hickson J, Tanlimco S, Fox M, Chao D, Hsi E, Sho M, Powers R, Foster-Duke K, McGonigal T, Uziel T, Kumar S, Samayoa J, Longenecker K, Lai D, Hollenbaugh D, Afar D, Iyer S, Morgan-Lappe S, Gish K. ABBV-085 is a novel antibody–drug conjugate (ADC) that targets LRRC15 in the tumor microenvironment. Eur J Cancer 2016. [DOI: 10.1016/s0959-8049(16)32622-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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de Courcy J, Wood R, Mitra D, Iyer S. Satisfaction with cancer treatments in HR + /HER2- metastatic breast cancer patients in a real world setting. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw365.62] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Loibl S, Demichele A, Turner N, Cristofanilli M, Loi S, Verma S, Bhattacharyya H, Ke Z, Giorgetti C, Bartlett C, Iyer S, Colleoni M, Masuda N, Im SA, Harbeck N. Impact of palbociclib plus fulvestrant on patient reported general health status compared with fulvestrant alone in HR +, HER2- metastatic breast cancer. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw365.39] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Rugo H, Dieras V, Gelmon K, Finn R, Slamon D, Miguel M, Neven P, Ettl J, Shparyk Y, Mori A, Lu D, Bhattacharyya H, Bartlett C, Iyer S, Johnston S, Harbeck N. Impact of palbociclib plus letrozole on health related quality of life (HRQOL) compared with letrozole alone in treatment naïve postmenopausal patients with ER+ HER2- metastatic breast cancer (MBC): results from PALOMA-2. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw365.04] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Zeng J, Kumar S, Iyer S, Schiraldi DA, Gonzalez RI. Reinforcement of Poly(ethylene terephthalate) Fibers with Polyhedral Oligomeric Silsesquioxanes (POSS). HIGH PERFORM POLYM 2016. [DOI: 10.1177/0954008305055562] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Poly(ethylene terephthalate) (PET)-based composite fibers were prepared by melt spinning three types of PET/polyhedral oligomeric silsesquioxane (POSS) composites. These composites were made by either melt blending POSS with PET at 5 wt% loading level (non-reactive POSS and silanol POSS) or by in-situ polymerization with 2.5 wt% reactive POSS. Significant increases in tensile modulus and tensile strengths were achieved in PET fibers with non-reactive POSS at room temperature. The hightemperature modulus retention was found to be much better for PET/silanol POSS fiber when compared to that of control PET. Although other PET/POSS nancomposite fibers tested did not show this high retention of modulus at elevated temperatures, PET/isooctylPOSS nanocomposite fibers did show increased modulus at elevated temperature compared to that of PET. Higher compressive strengths, compared to PET fibers, were observed for all three nanocomposite fibers. Gel permeation chromatography measurement suggested that there is no significant change in molecular weight during preparation of PET/POSS nanocomposites. SEM observations suggest that there is no obvious phase separation in any of the three PET/POSS systems. Crystallization behavior and thermal stability of the composite were also studied. The fiber spinning and mechanical performance with 10 and 20 wt% of trisilanolisooctyl POSS2 were also investigated1 the composites with higher concentrations of this nanofiller can be spun without any difficulty. At room temperature, the fiber tensile modulus increased steadily with the POSS concentration while fiber tensile strength showed no significant change. The elongation at break decreased significantly with increasing of POSS concentration. The high-temperature moduli of PET/POSS nanocomposite fibers were found to be rather variable, likely due to the modest compatibility between filler and polymers, which can lead to structural anisotropy within the composite.
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Harbeck N, Iyer S, Turner N, Cristofanilli M, Ro J, André F, Loi S, Verma S, Iwata H, Bhattacharyya H, Puyana Theall K, Bartlett CH, Loibl S. Quality of life with palbociclib plus fulvestrant in previously treated hormone receptor-positive, HER2-negative metastatic breast cancer: patient-reported outcomes from the PALOMA-3 trial. Ann Oncol 2016; 27:1047-1054. [PMID: 27029704 PMCID: PMC4880065 DOI: 10.1093/annonc/mdw139] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 03/17/2016] [Indexed: 11/14/2022] Open
Abstract
In treating HR+, HER2− metastatic breast cancer, novel agents that enhance endocrine therapy activity but do not worsen quality of life (QoL) are clinically desired. Patient-reported outcomes data from the PALOMA-3 study suggest palbociclib plus fulvestrant allow patients to maintain good QoL in the endocrine resistance setting while experiencing a substantially delayed disease progression. Background In the PALOMA-3 study, palbociclib plus fulvestrant demonstrated improved progression-free survival compared with fulvestrant plus placebo in hormone receptor-positive, HER2− endocrine-resistant metastatic breast cancer (MBC). This analysis compared patient-reported outcomes (PROs) between the two treatment groups. Patients and methods Patients were randomized 2 : 1 to receive palbociclib 125 mg/day orally for 3 weeks followed by 1 week off (n = 347) plus fulvestrant (500 mg i.m. per standard of care) or placebo plus fulvestrant (n = 174). PROs were assessed on day 1 of cycles 1–4 and of every other subsequent cycle starting with cycle 6 using the EORTC QLQ-C30 and its breast cancer module, QLQ-BR23. High scores (range 0–100) could indicate better functioning/quality of life (QoL) or worse symptom severity. Repeated-measures mixed-effect analyses were carried out to compare on-treatment overall scores and changes from baseline between treatment groups while controlling for baseline. Between-group comparisons of time to deterioration in global QoL and pain were made using an unstratified log-rank test and Cox proportional hazards model. Results Questionnaire completion rates were high at baseline and during treatment (from baseline to cycle 14, ≥95.8% in each group completed ≥1 question on the EORTC QLQ-C30). On treatment, estimated overall global QoL scores significantly favored the palbociclib plus fulvestrant group [66.1, 95% confidence interval (CI) 64.5–67.7 versus 63.0, 95% CI 60.6–65.3; P = 0.0313]. Significantly greater improvement from baseline in pain was also observed in this group (−3.3, 95% CI −5.1 to −1.5 versus 2.0, 95% CI −0.6 to 4.6; P = 0.0011). No significant differences were observed for other QLQ-BR23 functioning domains, breast or arm symptoms. Treatment with palbociclib plus fulvestrant significantly delayed deterioration in global QoL (P < 0.025) and pain (P < 0.001) compared with fulvestrant alone. Conclusion Palbociclib plus fulvestrant allowed patients to maintain good QoL in the endocrine resistance setting while experiencing substantially delayed disease progression. Clinical Trial Registration NCT01942135.
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Pandey M, Vidhyadharan S, Puthalath U, Veeraraghavan R, Sukumaran SV, Prasad C, Iyer S, Thankappan K. Macroscopic technique for the evaluation of oral tongue tumour thickness: a reliable intraoperative method. Int J Oral Maxillofac Surg 2016; 45:933-7. [PMID: 27034158 DOI: 10.1016/j.ijom.2016.03.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 01/26/2016] [Accepted: 03/11/2016] [Indexed: 10/22/2022]
Abstract
There is no reliable method to assess tumour thickness preoperatively or intraoperatively in cases of oral tongue squamous cell carcinoma (SCC). The purpose of this study was to evaluate the efficacy of a macroscopic technique to measure tumour thickness. This was a prospective study of 51 consecutive patients with T1/T2 primary SCC of the oral tongue. All patients underwent primary resection with ipsilateral neck dissection. Thickness measurements were obtained using Vernier calipers on the fresh specimen. The technique was correlated with the microscopic evaluation statistically using (1) Pearson's correlation coefficient, (2) intra-class correlation, and (3) Bland-Altman plot with 95% confidence intervals. On comparing the macroscopic technique to the microscopic evaluation, Pearson's correlation (r) was 0.915 (P<0.001). The inter-rater reliability using the intra-class correlation coefficient was 0.955. The Bland-Altman plot to test the agreement between the techniques showed the average difference between macroscopic thickness and microscopic thickness (bias) to be -0.421, with 95% limits of agreement of -3.166 and 2.82. There was a significant correlation and agreement between the macroscopic and microscopic measures of tumour thickness. The macroscopic technique could be used as a reliable tool to measure tumour thickness intraoperatively, prior to neck dissection.
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Chasapi M, Salibi A, Wain R, Iyer S. A Rare Case of Triple Neuromas As a Cause of Chronic Stump Pain in an Upper Limb Amputee. EPLASTY 2016; 16:ic11. [PMID: 27011782 PMCID: PMC4796878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Lopez-Hilfiker FD, Mohr C, D'Ambro EL, Lutz A, Riedel TP, Gaston CJ, Iyer S, Zhang Z, Gold A, Surratt JD, Lee BH, Kurten T, Hu WW, Jimenez J, Hallquist M, Thornton JA. Molecular Composition and Volatility of Organic Aerosol in the Southeastern U.S.: Implications for IEPOX Derived SOA. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:2200-9. [PMID: 26811969 DOI: 10.1021/acs.est.5b04769] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We present measurements as part of the Southern Oxidant and Aerosol Study (SOAS) during which atmospheric aerosol particles were comprehensively characterized. We present results utilizing a Filter Inlet for Gases and AEROsol coupled to a chemical ionization mass spectrometer (CIMS). We focus on the volatility and composition of isoprene derived organic aerosol tracers and of the bulk organic aerosol. By utilizing the online volatility and molecular composition information provided by the FIGAERO-CIMS, we show that the vast majority of commonly reported molecular tracers of isoprene epoxydiol (IEPOX) derived secondary organic aerosol (SOA) is derived from thermal decomposition of accretion products or other low volatility organics having effective saturation vapor concentrations <10(-3) μg m(-3). In addition, while accounting for up to 30% of total submicrometer organic aerosol mass, the IEPOX-derived SOA has a higher volatility than the remaining bulk. That IEPOX-SOA, and more generally bulk organic aerosol in the Southeastern U.S. is comprised of effectively nonvolatile material has important implications for modeling SOA derived from isoprene, and for mechanistic interpretations of molecular tracer measurements. Our results show that partitioning theory performs well for 2-methyltetrols, once accretion product decomposition is taken into account. No significant partitioning delays due to aerosol phase or viscosity are observed, and no partitioning to particle-phase water or other unexplained mechanisms are needed to explain our results.
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Brooks R, Iyer S, Akada H, Neelam S, Russo CM, Chisholm JD, Kerr WG. Coordinate expansion of murine hematopoietic and mesenchymal stem cell compartments by SHIPi. Stem Cells 2015; 33:848-58. [PMID: 25402778 DOI: 10.1002/stem.1902] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/22/2014] [Accepted: 10/27/2014] [Indexed: 11/07/2022]
Abstract
Promoting the expansion of adult stem cell populations offers the potential to ameliorate radiation or chemotherapy-induced bone marrow failure and allows for expedited recovery for patients undergoing these therapies. Previous genetic studies suggested a pivotal role for SH2 domain-containing inositol-5-phosphatase 1 (SHIP1) in limiting the size of the hematopoietic stem cell (HSC) compartment. The aim of this study was to determine whether our recent development of small molecule SHIP1 inhibitors offers the potential for pharmacological expansion of the HSC compartment in vivo. We show here that treatment of mice with aminosteroid inhibitors of SHIP1 (SHIPi) more than doubles the size of the adult mesenchymal stem cell (MSC) compartment while simultaneously expanding the HSC pool sixfold. Consistent with its ability to target SHIP1 function in vivo, SHIPi also significantly increases plasma granulocyte colony-stimulating factor (G-CSF) levels, a growth factor that supports proliferation of HSC. Here, we show that SHIPi-induced G-CSF production mediates HSC and MSC expansion, as in vivo neutralization of G-CSF abrogates the SHIPi-induced expansion of both the HSC and MSC compartments. Due to its expansionary effect on adult stem cell compartments, SHIPi represents a potential novel strategy to improve declining stem cell function in both therapy induced and genetically derived bone marrow failure syndromes.
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Iyer S, Casey E, Bouzek H, Kim M, Deng W, Larsen BB, Zhao H, Bumgarner RE, Rolland M, Mullins JI. Comparison of Major and Minor Viral SNPs Identified through Single Template Sequencing and Pyrosequencing in Acute HIV-1 Infection. PLoS One 2015; 10:e0135903. [PMID: 26317928 PMCID: PMC4552882 DOI: 10.1371/journal.pone.0135903] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 07/27/2015] [Indexed: 01/03/2023] Open
Abstract
Massively parallel sequencing (MPS) technologies, such as 454-pyrosequencing, allow for the identification of variants in sequence populations at lower levels than consensus sequencing and most single-template Sanger sequencing experiments. We sought to determine if the greater depth of population sampling attainable using MPS technology would allow detection of minor variants in HIV founder virus populations very early in infection in instances where Sanger sequencing detects only a single variant. We compared single nucleotide polymorphisms (SNPs) during acute HIV-1 infection from 32 subjects using both single template Sanger and 454-pyrosequencing. Pyrosequences from a median of 2400 viral templates per subject and encompassing 40% of the HIV-1 genome, were compared to a median of five individually amplified near full-length viral genomes sequenced using Sanger technology. There was no difference in the consensus nucleotide sequences over the 3.6kb compared in 84% of the subjects infected with single founders and 33% of subjects infected with multiple founder variants: among the subjects with disagreements, mismatches were found in less than 1% of the sites evaluated (of a total of nearly 117,000 sites across all subjects). The majority of the SNPs observed only in pyrosequences were present at less than 2% of the subject’s viral sequence population. These results demonstrate the utility of the Sanger approach for study of early HIV infection and provide guidance regarding the design, utility and limitations of population sequencing from variable template sources, and emphasize parameters for improving the interpretation of massively parallel sequencing data to address important questions regarding target sequence evolution.
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Caruana EJ, Iyer S, Kadlec J, Mani A, Solli P, Scarci M. O-134USE OF THE AQUAMANTYS® SYSTEM IN OPEN DECORTICATION FOR THORACIC EMPYEMA. Interact Cardiovasc Thorac Surg 2015. [DOI: 10.1093/icvts/ivv204.134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Silva M, Pham N, Lewis C, Iyer S, Kwok E, Solomon G, Zeise L. A Comparison of ToxCast Test Results with In Vivo and Other In Vitro Endpoints for Neuro, Endocrine, and Developmental Toxicities: A Case Study Using Endosulfan and Methidathion. ACTA ACUST UNITED AC 2015; 104:71-89. [PMID: 26017137 DOI: 10.1002/bdrb.21140] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/27/2015] [Indexed: 11/10/2022]
Abstract
INTRODUCTION The U.S. Environmental Protection Agency's (EPA's) Toxicity Forecaster (ToxCast) is a potential tool for chemical prioritization, hazard identification, and risk assessment. We conducted a case study to compare ToxCast data with endpoints from other in vitro and in vivo studies for two data-rich pesticides: endosulfan and methidathion. METHODS ToxCast assays for endocrine disruption, development (zebrafish), and neurotoxicity were qualitatively compared to traditional neurotoxicity, developmental and reproductive toxicity findings. We also used in vitro-in vivo extrapolation to convert half-maximal activity concentrations in active ToxCast assays to rat oral equivalent doses, and quantitatively compared these to the lowest observable effect level (LOEL) from in vivo studies. RESULTS Endosulfan was inactive for GABAA R, unlike in vivo; but active with dopamine transporter assays and was neurotoxic in zebrafish as expected. Methidathion was not active for these endpoints in vivo or in vitro. Acetylcholinesterase inhibition was ToxCast-inactive, although both pesticides are inhibitors in vivo. ToxCast results were generally inactive for endosulfan estrogen receptor agonism and androgen receptor antagonism unlike in vivo. Calculated oral equivalent doses for estrogen receptor and androgen receptor pathways and for zebrafish assays for both compounds were generally consistent with in vivo LOELs. Endosulfan showed neurotoxicity and both pesticides showed developmental effects in the zebrafish assays, although methidathion is not developmentally toxic in vivo. CONCLUSIONS ToxCast's predictions showed concordance on some endpoints and nonconcordance, consisting mainly of false inactives, in several critical endpoints, likely due to a lack of metabolic activation and limitations in assay design. Zebrafish assays were good predictors of developmental toxicity and neurotoxicity for endosulfan.
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Iyer S, Bell F, Westphal D, Anwari K, Gulbis J, Smith BJ, Dewson G, Kluck RM. Bak apoptotic pores involve a flexible C-terminal region and juxtaposition of the C-terminal transmembrane domains. Cell Death Differ 2015; 22:1665-75. [PMID: 25744027 DOI: 10.1038/cdd.2015.15] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 01/07/2015] [Accepted: 01/21/2015] [Indexed: 12/22/2022] Open
Abstract
Bak and Bax mediate apoptotic cell death by oligomerizing and forming a pore in the mitochondrial outer membrane. Both proteins anchor to the outer membrane via a C-terminal transmembrane domain, although its topology within the apoptotic pore is not known. Cysteine-scanning mutagenesis and hydrophilic labeling confirmed that in healthy mitochondria the Bak α9 segment traverses the outer membrane, with 11 central residues shielded from labeling. After pore formation those residues remained shielded, indicating that α9 does not line a pore. Bak (and Bax) activation allowed linkage of α9 to neighboring α9 segments, identifying an α9:α9 interface in Bak (and Bax) oligomers. Although the linkage pattern along α9 indicated a preferred packing surface, there was no evidence of a dimerization motif. Rather, the interface was invoked in part by Bak conformation change and in part by BH3:groove dimerization. The α9:α9 interaction may constitute a secondary interface in Bak oligomers, as it could link BH3:groove dimers to high-order oligomers. Moreover, as high-order oligomers were generated when α9:α9 linkage in the membrane was combined with α6:α6 linkage on the membrane surface, the α6-α9 region in oligomerized Bak is flexible. These findings provide the first view of Bak carboxy terminus (C terminus) membrane topology within the apoptotic pore.
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Jing SS, Iyer S. The ABC guide for the safe use of mini C-arms. Ann R Coll Surg Engl 2015; 97:162. [PMID: 25723703 DOI: 10.1308/rcsann.2015.97.2.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Clayton K, Creech L, Townley B, Iyer S, Sheikh H. 101: Increasing input from research nurse and lung CNS improves recruitment to clinical trials. Lung Cancer 2015. [DOI: 10.1016/s0169-5002(15)50096-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Fiskus W, Sharma S, Saha S, Shah B, Devaraj SGT, Sun B, Horrigan S, Leveque C, Zu Y, Iyer S, Bhalla KN. Pre-clinical efficacy of combined therapy with novel β-catenin antagonist BC2059 and histone deacetylase inhibitor against AML cells. Leukemia 2014; 29:1267-78. [PMID: 25482131 PMCID: PMC4456205 DOI: 10.1038/leu.2014.340] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 10/10/2014] [Accepted: 10/16/2014] [Indexed: 12/15/2022]
Abstract
The canonical WNT-β-catenin pathway is essential for self-renewal, growth and survival of AML stem/blast progenitor cells (BPCs). Deregulated WNT signaling inhibits degradation of β-catenin, causing increased nuclear translocation and co-factor activity of β-catenin with the transcriptional regulator TCF4/LEF1 in AML BPCs. Here, we determined the pre-clinical anti-AML activity of the anthraquinone oxime-analog BC2059 (BC), known to attenuate β-catenin levels. BC treatment disrupted the binding of β-catenin with the scaffold protein TBL1 (transducin β-like 1) and proteasomal degradation and decline in the nuclear levels of β-catenin. This was associated with reduced transcriptional activity of TCF4 and expression of its target genes, cyclin D1, c-MYC and survivin. BC treatment dose-dependently induced apoptosis of cultured and primary AML BPCs. Treatment with BC also significantly improved the median survival of immune-depleted mice engrafted with either cultured or primary AML BPCs exhibiting nuclear expression of β-catenin. Co-treatment with the pan-histone deacetylase inhibitor panobinostat and BC synergistically induced apoptosis of cultured and primary AML BPCs, including those expressing FLT3-ITD, as well as further significantly improved the survival of immune-depleted mice engrafted with primary AML BPCs. These findings underscore the promising pre-clinical activity and warrant further testing of BC against human AML, especially those expressing FLT3-ITD.
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