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Dietary restriction of cysteine and methionine sensitizes gliomas to ferroptosis and induces alterations in energetic metabolism. Nat Commun 2023; 14:1187. [PMID: 36864031 PMCID: PMC9981683 DOI: 10.1038/s41467-023-36630-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 02/07/2023] [Indexed: 03/04/2023] Open
Abstract
Ferroptosis is mediated by lipid peroxidation of phospholipids containing polyunsaturated fatty acyl moieties. Glutathione, the key cellular antioxidant capable of inhibiting lipid peroxidation via the activity of the enzyme glutathione peroxidase 4 (GPX-4), is generated directly from the sulfur-containing amino acid cysteine, and indirectly from methionine via the transsulfuration pathway. Herein we show that cysteine and methionine deprivation (CMD) can synergize with the GPX4 inhibitor RSL3 to increase ferroptotic cell death and lipid peroxidation in both murine and human glioma cell lines and in ex vivo organotypic slice cultures. We also show that a cysteine-depleted, methionine-restricted diet can improve therapeutic response to RSL3 and prolong survival in a syngeneic orthotopic murine glioma model. Finally, this CMD diet leads to profound in vivo metabolomic, proteomic and lipidomic alterations, highlighting the potential for improving the efficacy of ferroptotic therapies in glioma treatment with a non-invasive dietary modification.
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Quantification of mitral regurgitation and biventricular assessment is feasible during continuous supine exercise cardiovascular magnetic resonance in primary mitral regurgitation patients. Eur Heart J Cardiovasc Imaging 2021. [DOI: 10.1093/ehjci/jeab090.104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Biventricular volume and great vessel flow assessment during continuous supine free-breathing exercise cardiovascular magnetic resonance (Ex-CMR) is feasible in healthy volunteers using Compressed SENSEx3 (CS3) sequences1. Exercise transthoracic echocardiography (TTE) provides prognostic information in primary mitral regurgitation (MR). Resting CMR offers reference standard biventricular assessment and MR quantification with superior reproducibility to TTE. Ex-CMR assessment of biventricular volumes and quantitated MR may offer additional prognostic information.
Purpose
Determine the feasibility of biventricular assessment and MR quantification in primary MR patients during continuous supine Ex-CMR using the recently validated protocol1.
Methods
10 asymptomatic patients with at least moderate primary MR on TTE (8 male, median age 62, 55-67years interquartile range) underwent continuous in-scanner (1.5T Philips Ingenia) supine cycle ergometer (Lode BV) Ex-CMR. Target heart rates (THR) were individually prescribed using heart rate reserve (HRR) and age predicted maximal heart rate model. Participants exercised for 2-minutes at no resistance, then an increase of 25-Watts every 2-minutes until THR achieved at low (30-39% HRR), then moderate (40-59% HRR) stages. CMR imaging: free-breathing CS3 respiratory navigated short axis cine imaging and free-breathing CS3 aortic phase-contrast magnetic-resonance at rest, low and moderate exercise stages. MR was quantified indirectly from left ventricular (LV) and aortic stroke volumes. Intra/inter-observer reproducibility was assessed by coefficient of variance (CV).
Results
All patients completed the Ex-CMR protocol without complication. During exercise, no statistically significant changes occurred in LV volumes, global left ventricular ejection fraction (LVEF), right ventricular end-diastolic or systolic volumes (Table 1). From rest to low and moderate exercise: right ventricular ejection fraction increased (55 ± 5.4% to 60 ± 6.0% and 63 ± 6.6% respectively, p = 0.001) and MR fraction decreased (40 ± 14% to 36 ± 11% and 30 ± 15% respectively, p = 0.006) allowing effective forward LVEF (aortic stroke volume/ left ventricular end-diastolic volume) to increase (38 ± 9.3% to 43 ± 9.3% and 46 ± 11% respectively, p = 0.004). Intra-observer reproducibility (Table 2) was excellent (CV <10%), except right ventricular stroke volumes (RVSV) during low, MR volumes and fraction during moderate and right ventricular end-systolic volumes (RVESV) during both exercise stages, which were good (CV10-20%). Inter-observer reproducibility (Table 2) was excellent (CV < 10%), except RVESV and MR volumes at all stages, LV end-systolic volumes during low and MR fraction during moderate exercise, which were good (CV 10-20%).
Conclusion
Biventricular assessment and MR quantification during continuous supine Ex-CMR is feasible in asymptomatic primary MR patients, further research assessing the techniques prognostic ability is now warranted.
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Right occipital transtentorial approach for a pineal malignant germ cell tumor. NEUROSURGICAL FOCUS: VIDEO 2021; 5:V3. [PMID: 36284916 PMCID: PMC9549986 DOI: 10.3171/2021.4.focvid2151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 04/14/2021] [Indexed: 06/16/2023]
Abstract
Germ cell tumors account for up to 53% of the malignant lesions found in the pineal region and are typically managed with a combination of radiation therapy and chemotherapy. Malignant somatic transformation of intracranial germ cell tumors is exceedingly rare and has only been reported on two other occasions. Here the authors present the case of a pineal yolk sac tumor that failed optimum first-line treatment and underwent malignant somatic transformation to an enteric mucinous adenocarcinoma requiring surgical intervention. This video demonstrates the technical nuances of the occipital transtentorial approach and the safe microsurgical dissection of lesions within the pineal region. The video can be found here: https://stream.cadmore.media/r10.3171/2021.4.FOCVID2151.
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The Sledgehammer in Precision Medicine: Dexamethasone and Immunotherapeutic Treatment of Glioma. Cancer Invest 2021; 40:554-566. [PMID: 34151678 DOI: 10.1080/07357907.2021.1944178] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Understanding dexamethasone's effect on the immune microenvironment in glioma patients is of key importance. We performed a comprehensive literature review using the NCBI PubMed database for all articles meeting the following search criteria. ((dexamethasone[All Fields]) AND (glioma or glioblastoma)[Title/Abstract]) AND (immune or T cell or B cell or monocyte or neutrophil or macrophage). Forty-three manuscripts were deemed relevant to the topic at hand. Multiple clinical studies have linked dexamethasone use to decreased overall survival while preclinical studies in murine glioma models have demonstrated decreased tumor-infiltrating lymphocytes after dexamethasone administration.
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Abstract
Although radiation is widely used to treat cancers, resistance mechanisms often develop and involve activation of DNA repair and inhibition of apoptosis. Therefore, compounds that sensitize cancer cells to radiation via alternative cell death pathways are valuable. We report here that ferroptosis, a form of nonapoptotic cell death driven by lipid peroxidation, is partly responsible for radiation-induced cancer cell death. Moreover, we found that small molecules activating ferroptosis through system xc- inhibition or GPX4 inhibition synergize with radiation to induce ferroptosis in several cancer types by enhancing cytoplasmic lipid peroxidation but not increasing DNA damage or caspase activation. Ferroptosis inducers synergized with cytoplasmic irradiation, but not nuclear irradiation. Finally, administration of ferroptosis inducers enhanced the antitumor effect of radiation in a murine xenograft model and in human patient-derived models of lung adenocarcinoma and glioma. These results suggest that ferroptosis inducers may be effective radiosensitizers that can expand the efficacy and range of indications for radiation therapy.
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Abstract OT3-01-03: A phase I trial of the safety and immunogenicity of a DNA plasmid based vaccine (WOKVAC) encoding epitopes derived from three breast cancer antigens (IGFBP2, HER2, and IGF1R) in patients with breast cancer. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-ot3-01-03] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Three proteins insulin like growth factor binding protein 2 (IGFBP2), human epidermal growth factor receptor 2 (HER2), and insulin like growth factor receptor-1 (IGF1R) are overexpressed in in pre-invasive and high risk breast lesions and are associated with progression to invasive breast cancer. These proteins are immunogenic and elicit both humoral and cellular immunity in breast cancer patients. It is hypothesized that immunization with a plasmid vaccine (WOKVAC) targeting antigens from these proteins will be safe and immunogenic. WOKVAC has been designed to include extended sequences of the immunizing antigens that are predominantly associated with eliciting Type I immune responses. Type I immunity results in immune cells called T-cells secreting high levels of inflammatory cytokines (called Th1) that stimulate tumor destruction as well as the generation of cytotoxic T-cells that can directly kill the tumors.
Trial design: Phase I dose escalation study of 3 doses of WOKVAC admixed with 100mcg of GM-CSF. Patients will be assigned sequentially to one of three arms (10 patients/arm): Arm 1=150mcg, Arm 2=300mcg, Arm 3=600mcg. Each dose arm will have a staggered enrollment to assess toxicity. If the Arm 1 dose is determined to be safe, Arm 2 patients can be enrolled. If the Arm 2 dose is safe and immunologically more efficacious than Arm 1 then Arm 3 patients can be enrolled. Study treatment includes 3 monthly vaccines, two evaluations at 1 and 6 months post vaccine and a 5 year follow-up to collect reports from the patient's primary oncologist. Toxicity is assessed at baseline through the end of the study. Serial blood draws for immunologic monitoring is done.
Eligibility criteria: Patients with non-metastatic, node positive, HER2 negative breast cancer that is in remission and defined as no evidence of disease. Patients must have a good performance status, be at least 28 days from last cytotoxic chemotherapy and/or radiotherapy and 28 days from any use of systemic steroids.
Specific aims: (1) Determine safety of 3 escalating doses of WOKVAC, (2) Determine the most immunogenic dose, (3) Determine whether a WOKVAC Th1 polyepitope plasmid based vaccine elicits a persistent memory T-cell and (4) Determine whether WOKVAC vaccination modulates T regulatory cells and myeloid derived suppressor cells.
Statistical methods: (1) Safety will be assessed per NCI CTCAE v. 4.0, (2) Immunogenicity will be defined by the magnitude of the Th1 IFN-gamma antigen specific immune response. Successful immunization is a protein specific IFN-g precursor frequency greater than 1:20,000 PBMC for each antigen or 2 fold increase if baseline immune response (3) The IGFBP2, HER2, and IGF1R specific IFN-g/IL-10 ratios by ELISPOT will be evaluated to determine that a predominantly Th1 immune response is stimulated, and (4) Humoral immune response will be measured by ELISA and serum antibody avidity for IGFBP2, HER2, and IGF1R to determine an avidity index (AI) before and after vaccination.
Targeted Accrual: 30 patients
Contact information:
University of Washington: 866-392-8588/TrialTVG@uw.edu
University of Wisconsin: 608-265-2493/prevention@uwcarbone.wisc.edu.
Citation Format: Childs JS, Higgins DM, DeShong K, Heckman-Stoddard BM, Wojtowicz ME, Stanton SE, Bailey HH, Wisinski KB, Disis ML. A phase I trial of the safety and immunogenicity of a DNA plasmid based vaccine (WOKVAC) encoding epitopes derived from three breast cancer antigens (IGFBP2, HER2, and IGF1R) in patients with breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT3-01-03.
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Understanding the Impact of Obesity on Short-term Outcomes and In-hospital Costs After Instrumented Spinal Fusion. Neurosurgery 2016; 78:127-32. [PMID: 26352096 DOI: 10.1227/neu.0000000000001018] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Obesity rates continue to rise along with the number of obese patients undergoing elective spinal fusion. OBJECTIVE To evaluate the impact of obesity on resource utilization and early complications in patients undergoing surgery for degenerative spine disease. METHODS A single-institution retrospective analysis was conducted on patients with degenerative spine disease requiring instrumentation between 2008 and 2012. The 801 identified patients were grouped based on a body mass index (BMI) of <30 (nonobese, n = 478), ≥30 and <40 (obese, n = 283), and alternatively BMIs of ≥40 (morbidly obese, n = 40). Baseline characteristics, surgical outcomes and requirements, complications, and cost were compared. Logistic and linear regression analyses were used to determine the strength of association between obesity and outcomes for categorical and continuous data, respectively. RESULTS Significant differences were found in comorbidities between cohorts. Multivariate analysis revealed significant associations between obesity and longer anesthesia times (30 minutes, P = .008), and surgical times (24 minutes, P = .02). Additionally, there was a 2.8 times higher rate of wound complications in obese patients (4.2% vs 1.5, P = .03), and 2.5 times higher rate of major medical complications (7.8% vs 3.1, P = .01). Morbid obesity resulted in a 10 times higher rate of wound complications (P < .001). Morbid obesity resulted in a $9078 (P = .005) increase in overall cost of care. CONCLUSION Increased BMI is associated with longer operative times, increased complication rates, and increased cost independent of comorbidities. These effects are more pronounced with morbidly obese patients, further supporting a role for preoperative weight loss.
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Abstract
Study Design Retrospective case series. Objective To determine the effect of obesity on the resource utilization and cost in 3270 consecutive patients undergoing elective noninstrumented decompressive surgeries for degenerative spine disease at Mayo Clinic Rochester between 2005 and 2012. Methods Groups were assessed for baseline differences (age, gender, and American Society of Anesthesiologists [ASA] classification, procedure type, and number of operative levels). Outcome variables included the transfusion requirements during surgery, the total anesthesia and surgical times, intensive care unit (ICU) admissions, standardized costs, as well as the ICU and hospital length of stay (LOS). Regression analysis was used to evaluate for strength of association between obesity and outcome variables. Results Baseline differences between the groups (nonobese: n = 1,853; obese: n = 1,417) were found with respect to age, ASA class, gender, procedure type, and number of operative levels. After correcting for differences, we found significant associations between obesity and surgical (p < 0.0001) and anesthesia times (p < 0.0001) and hospital LOS (p < 0.0001). Additionally, ICU admission rates (p = 0.02) and requirement for postoperative ventilation (p = 0.048) were significantly higher in obese patients. Finally, mean difference in total cost ($1,632, p < 0.0001) was significantly higher for the obese cohort. Conclusion Obesity is associated with increased resource utilization and cost in patients undergoing a noninstrumented decompressive surgery for degenerative spine disease.
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Brain tumor stem cell multipotency correlates with nanog expression and extent of passaging in human glioblastoma xenografts. Oncotarget 2013; 4:792-801. [PMID: 23801022 PMCID: PMC3742839 DOI: 10.18632/oncotarget.1059] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Accepted: 06/06/2013] [Indexed: 11/25/2022] Open
Abstract
Glioblastoma multiforme (GBM) is the most common primary brain tumor, with a median survival of only 15 months. A subpopulation of cells, the brain tumor stem cells (BTSCs), may be responsible for the malignancy of this disease. Xenografts have proven to be a robust model of human BTSCs, but the effects of long-term passaging have yet to be determined. Here we present a study detailing changes in BTSC multipotency, invasive migration, and proliferation after serial passaging of human GBM xenografts. Immunocytochemistry and tumorsphere formation assays demonstrated the presence of BTSCs in both early generation (EG-BTSCs; less than 15 passages) and late generation (LG-BTSCs; more than 24 passages) xenografts. The EG-BTSCs upregulated expression of lineage markers for neurons and oligodendrocytes upon differentiation, indicating multipotency. In contrast, the LG-BTSCs were restricted to an astrocytic differentiation. Quantitative migration and proliferation assays showed that EG-BTSCs are more migratory and proliferative than LG-BTSCs. However, both populations respond similarly to the chemokine SDF-1 by increasing invasive migration. These differences between the EG- and LG-BTSCs were correlated with a significant decrease in nanog expression as determined by qRT-PCR. Mice implanted intracranially with EG-BTSCs showed shorter survival when compared to LG-BTSCs. Moreover, differentiation prior to implantation of EG-BTSCs, but not LG-BTSCs, led to increased survival. Thus, nanog may identify multipotent BTSCs. Furthermore, limited passaging of xenografts preserves these multipotent BTSCs, which may be an essential underlying feature of GBM lethality.
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Abstract OT3-1-02: Phase II randomized study of combination immunotherapy with or without Polysaccharide Krestin (PSK®) concurrently with a HER2 ICD peptide-based vaccine and trastuzumab in patients with stage IV breast cancer. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-ot3-1-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Endogenous immunity in patients with HER2+ metastatic breast cancer (MBC) is likely dampened by an immune-suppressive tumor microenvironment and not sufficient to control tumor growth. Thus, most patients have disease relapse after achieving complete remission with standard therapies. Immunomodulation directed at enhanced stimulation of tumor specific immunity could result in immunologic eradication of residual HER2+ tumor cells and prevent BC relapse. We have shown PSK to be a potent TLR-2 agonist that stimulates both innate and adaptive immunity in a BC mouse model. Additionally, we have shown combination immunotherapy with HER2 peptide vaccines and trastuzumab (TRAZ) to be safe and able to elicit HER2 specific Th1 immunity and epitope spreading (ES) which has been associated with survival in vaccinated patients. Lastly, decreased serum TGF-β elicited by HER2 vaccination correlates with Th1 ES and may serve as a biomarker to predict cancer vaccine efficacy. We hypothesize that PSK, when given with TRAZ can augment vaccine induced HER2 specific TH1 immunity and prevent disease relapse in patients with optimally treated HER2+ MBC.
Trial design: Phase II randomized two-arm clinical trial. Patients will be enrolled and randomly assigned in equal numbers to 1 of 2 arms (15 patients/arm) as follows: Arm 1:HER2 ICD vaccine, TRAZ and placebo or Arm 2:HER2 ICD vaccine, TRAZ and PSK. All patients will receive 3 monthly HER2 ICD vaccines plus TRAZ and 4 months of concomitant PSK or placebo. Serial blood draws for immunologic monitoring will be done.
Eligibility criteria: Patients with Stage IV HER2+ BC who have been treated with definitive therapy and are: (1) without evidence of disease or have stable-bone only disease, (2) receiving TRAZ monotherapy, and (3) without clinically significant autoimmune disease. Patients must have normal LVEF per MUGA scan or echocardiogram.
Aims: (1) Evaluate safety of PSK when given with a HER2 vaccine and TRAZ (2) Evaluate the effect of PSK on serum TGF-β levels when given with a HER2 vaccine and TRAZ and (3) Evaluate the effect of PSK on intermolecular ES when given with a HER2 vaccine and TRAZ. A secondary objective is to evaluate progression free survival (PFS) and overall survival (OS).
Statistical methods: (1) Toxicity will be determined by clinical and chemical parameters and grading will be done per CTEP CTCAE 4.0.; (2) Evaluation of TGF-β levels, pre and post-PSK treatment will be assessed with linear regression models; and analysis of multiple post-baseline measurements will be performed using generalized estimating equations; (3) A positive antigen-specific immune response will be defined as a precursor frequency >1:20,000 antigen-specific peripheral blood mononuclear cells. Differences in the levels of HER2 immunity will be evaluated between arms using a two-tailed T test. The degree of ES in each arm will be evaluated with generalized linear modeling; (4) Large differences in PFS and OS observed between groups will be noted and described.
Target accrual: 30 patients.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT3-1-02.
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Abstract
OBJECT Rathke cleft cysts (RCCs) are benign masses arising from the embryological Rathke pouch, and are commonly treated by transsphenoidal surgery. The authors retrospectively compared RCC extent of resection-either gross-total resection (GTR) or decompression-to the primary outcome measure, which was recurrences resulting in repeat surgery, and the secondary outcome measure, which was complications. METHODS Seventy-four patients presenting to the neurosurgical department with RCC were analyzed retrospectively. Sixty-eight patients had a total of 78 surgical procedures, with the diagnosis of RCC confirmed by histological investigation; of these, 61 patients had adequate operative notes for the authors to evaluate extent of resection. Groups were separated into GTR (32 patients) or decompression (subtotal resection or fenestration into the sphenoid sinus; 29 patients) based on operative notes and postoperative imaging. The mean follow-up duration was 60.5 ± 72.1 months (the mean is expressed ± SD throughout). RESULTS The average age at the time of the initial surgery was 42.8 ± 17.4 years, and 70% of patients were female. The mean cyst diameter preoperatively was 16.9 ± 17.8 mm. Eight patients had repeat surgery, our primary outcome measure; 3 repeat operations occurred in the GTR group, and 5 in the decompression group. There was no significant difference in recurrence when comparing groups (GTR 9%, decompression 17%; p = 0.36). There were no major complications; however, analysis of postoperative minor complications revealed that 11 (34%) GTRs resulted in surgical complications, whereas the decompression cohort accounted for only 3 complications (10%) (p = 0.03), with diabetes insipidus (6) and CSF leaks (5) being the most common. Gross-total resection also resulted in an increase in postoperative hyperprolactinemia compared with decompression (p = 0.03). CONCLUSIONS It appears that RCCs require repeat surgery in 13% of cases, and attempted GTR does not appear to reduce the overall rate of recurrence. However, more aggressive resections are associated with more complications in this series.
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OT3-01-19: Phase II Study of Topical Imiquimod and Weekly Abraxane for the Treatment of Breast Cancer Cutaneous Metastases. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-ot3-01-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background
Breast cancer (BC) cutaneous lesions present as local chest wall recurrence or as isolated sites of metastatic disease. The treatment of cutaneous lesions is challenging and includes chest wall resection, local radiation therapy, and/or salvage chemotherapy which is not curative, associated with significant morbidity, and results in overall response rates of 20–30%. Thus, investigation of novel treatment strategies is warranted. This study incorporates multimodality treatment with topical imiquimod, a TLR-7agonist which generates an immune signal similar to that of pathogenic bacteria and Abraxane, a conventional systemic chemotherapy with potential immunostimulatory effects. Combined, these two agents provide local and systemic strategies which are potentially synergistic; and more effective than as single-agents in treating and controlling cutaneous disease.
Trial design: A Phase II single arm, non-randomized study. Patients will be sequentially enrolled and receive a maximum of 3 treatment cycles. A treatment cycle consists of topical imiquimod daily to target lesions for 4 days/week for 4 weeks in addition to Abraxane on Days 1, 8, and 15 every 28 days. Toxicity will be evaluated weekly during treatment then monthly for four months. Defined lesions are assessed at baseline and monthly. Skin biopsies are obtained pre and post treatment for histologic analysis and RT-PCR analysis of a 7 IFN-related gene signature previously associated with tumor inhibition. Immunity to BC antigens and serum TGF-β levels are also evaluated.
Aims: To evaluate the safety and anti-tumor effects of chemoimmunotherapy with topical imiquimod and Abraxane.
Eligibility criteria: Patients with progressive or relapsed BC after standard therapy who 1) have measurable cutaneous metastatic lesions, 2) are at least 7 days from last chemotherapy, 30 days from local radiotherapy and/or systemic steroids, 3) have adequate blood counts and 4) no history of active autoimmune disease. Bisphosphonates, trastuzumab, and/or hormonal therapy is allowed.
Statistical methods: Antitumor activity of target lesions will be assessed per modified WHO criteria. Complete response (CR)-complete clearance of lesions; Partial response (PR) ≥ 50% decrease in lesion size; Stable disease (SD) < 50% decrease in lesion size; Progressive disease (PD) increase in ≥ 25% lesion size). Historical overall response rates (ORR) with second and third line salvage chemotherapy range from 20–30%, with CR rates less than 2%. Based on these numbers, an ORR of 50% or a CR rate of 10% will be used as benchmarks for success (i.e., ≥8 responses or ≥2 CRs among 15 patients (observed ORR of ≥ 53% or observed CR rate of ≥ 13%) to consider the treatment worthy of further study. As a measure of the precision of the estimate of ORR achievable with 15 patients, if the response rate is 60%, we will be 80% confident that the observed RR is within 0.16 of the true RR with 15 patients treated. Toxicity will be evaluated by CTCAE v. 3.0 and descriptive statistics will be used to summarize changes from baseline and for reporting of immunological parameters.
Accrual: 10 patients received treatment with a target accrual of 15.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT3-01-19.
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OT2-05-05: Phase I/II Study of Adoptive T Cell Therapy Following In Vivo Priming with a HER2 Peptide-Based Vaccine in Patients with Stage IV Breast Cancer. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-ot2-05-05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background
Adoptive T cell therapy has evolved from preclinical setting to a potentially feasible treatment strategy for advanced breast cancer (BC). However, the ability to expand tumor antigen specific T cells ex vivo has been one of the major hurdles that has limited clinical translation of adoptive T cell therapy. Tumor specific T cells are rare in unprimed patients and generating large bulk cultures from rare precursor frequencies is difficult. We have found immunizing HER2+ patients to increase tumor specific T cell precursor frequencies to the levels of a vaccinated foreign antigen markedly improves the ability to generate large numbers of tumor specific T cells in vitro. We hypothesize that T cell expansion strategies that are facilitated by prior immunization will be clinically useful in the treatment of advanced BC.
Design: A Phase I/II non-randomized, single arm study. Priming with a HER2 ICD vaccine will be performed at 1 week intervals for a total of 3 vaccines. Patients will undergo leukapheresis 2 weeks after the 3rd vaccine to collect PBMC for T cell expansion. Patients will be pre-treated with cyclophosphamide 24 hours prior to 1st T cell infusion and then receive up to 3 dose-escalating infusions of T cells given 7–10 days apart. Three HER2 vaccine booster immunizations will then be administered at 1, 2, and 4 months after the final T cell infusion. Follow-up for persistent and continued immunity will then ensue.
Aims: To evaluate the safety of infusing escalating doses of HER2 specific T cells into patients with advanced HER2+ BC using ex vivo expanded autologous T cells, to investigate to what extent HER2 specific T cell immunity can be boosted or generated in individuals after infusion of HER2 specific T cells, to evaluate how long T cell immune augmentation persists in vivo after adoptive transfer of HER2 specific T cells and subsequent booster immunizations.
Criteria: Patients with HER2+ Stage IV BC who: have been maximally treated and not achieved a complete remission, have stable or slowly progressive disease, HER2+, and have adequate LVEF.
Statistical Methods: Toxicity will be determined by chemical and clinical parameters evaluated at various time points. If the true probability of a DLT is 0.11, then the probability of observing 0 DLT's in 20 patients is 0.097. If the true probability of a DLT is 0.18, then the probability of observing ≤1 DLT's in 20 patients is 0.102, and if the true probability of a DLT is 0.27, then the probability of observing ≤2 DLT's in 20 patients is 0.064. Therefore, with low observed rates of DLT (≤10%), we can be reasonably confident (∼90%) with 20 patients that the true DLT rate is < 0.27. Immunologic response, defined as the successful boosting of precursor frequency with infusion of HER2−specific T cells, will be evaluated by assessing the change in T cell level from baseline. To assess the durability of the T cell response, we are primarily interested in estimating the proportion of patients whose T cells persist at a level the same or greater as the level after the final T cell infusion as long as 6 months following the final booster vaccine.
Accrual: Target=20/Actual=14
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT2-05-05.
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OT1-02-10: Phase I-II Study of HER2 Vaccination with Poly(I) • Poly(C12U) (Ampligen®) as an Adjuvant in Optimally Treated Breast Cancer Patients. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-ot1-02-10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background
Despite improved response rates and overall survival, many HER2+ breast cancer (BC) patients have disease relapse suggesting residual microscopic disease. HER2 vaccines given with adjuvants that can enhance, sustain, and skew antigen immunogenicity toward a Th1 phenotype could induce robust tumor-specific Th1 immunity resulting in immunologic eradication of residual tumor cells and potentially prevent relapse. One such adjuvant is Ampligen which is highly selective as a TLR-3 agonist. Our pre-clinical studies show a dose effect in the tumor prevention efficacy of Ampligen when given as an adjuvant with vaccines. We hypothesize HER2 peptide vaccination given with standard adjuvant 100mcg GMCSF and Ampligen can induce a higher incidence and magnitude of protective HER2−specific Th1 immunity than with GMCSF alone.
Trial design: Phase I-II randomized 2-stage HER2 vaccine study. Stage I will enroll 40 patients (10/arm) into one of 4 Ampligen dose arms (4, 20, 79, or 495 mcg + HER2 vaccine). The Ampligen “maximum biologic dose” (MBD), the dose with the highest incidence/magnitude of immune response and lowest incidence of toxicity will be defined. Stage II will enroll 48 patients (24/arm) receiving Ampligen MBD + HER2 vaccine + GMCSF or HER2 vaccine + GMCSF to evaluate if Ampligen MBD increases the incidence and magnitude of immunity vs HER2 vaccine + GMCSF alone. Patients will be enrolled sequentially and randomized equally into all arms via a permuted block design. Patients will receive 3 monthly vaccines. Toxicity and immune response will be assessed.
Aims: 1) To evaluate toxicity and define the MBD of Ampligen as an adjuvant with HER2 vaccination 2) determine if Ampligen MBD when combined with GMCSF as adjuvant and HER2 vaccination increases incidence/magnitude of HER2 Th1 immunity compared to standard GMCSF alone.
Eligibility criteria: Stage II–IV HER2+ BC patients who: 1) have completed definitive standard treatment, and in clinical remission 2) 14 days post chemotherapy and steroids 3) have adequate blood counts 4) are off trastuzumab 5) have no active autoimmune disease.
Statistical methods: In aim 1, we expect mild toxicity between the 4 dose arms, thus lack of efficacy based on incidence of immune response will be evaluated. Six responses must be observed within a dose arm to move forward based on historical 60% response rate (RR) with standard GMCSF (probability of continuing if true RR is 40% and 70% is 0.17, 0.85, respectively). In aim 2, 24 patients/arm provides 80% power to detect 40% difference in incidence of immune response between the 2 groups (Pearson chi-square test, two-sided alpha of 0.05) and 82% power to assess a 0.85 SD unit difference in change between control and MBD, based on a 2-sample t-test (p=0.05) and effect size defined as the difference in the means divided by the common SD. Incidences of HER2 Th1 immunity will be compared across treatment arms via Pearson chi-square test; magnitude of immune response will be compared across groups via linear regression model.
Study Accrual: Target accrual is 88 patients: Stage 1 (n=40) and Stage II (n=48). There has been no accrual at this time.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT1-02-10.
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Preoperative embolization of the external carotid artery branches as an adjunct to superficial temporal artery-to-middle cerebral artery bypass. J Stroke Cerebrovasc Dis 2010; 20:168-71. [PMID: 20739190 DOI: 10.1016/j.jstrokecerebrovasdis.2009.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 11/06/2009] [Accepted: 11/16/2009] [Indexed: 10/19/2022] Open
Abstract
When technically feasible, the preferred revascularization procedure in patients with adult moyamoya disease is a superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass. The caliber of the STA has been reported as a prognostic factor for a successful bypass, with smaller-caliber STA being more likely to fail. We describe a novel approach to this circumstance in which preoperative embolization of external carotid artery (ECA) branches is used to augment blood flow through a small STA as a prelude to bypass surgery. We report 2 cases: a 42-year-old female presenting with symptomatic ischemic and radiographically progressive moyamoya disease and a 23-year-old female presenting with advanced moyamoya disease secondary to diabetes. Preoperative angiography demonstrated small-caliber STAs in each case, and primary revascularization was deemed difficult. Preoperative ECA embolization was undertaken to shunt blood toward the STA, thereby increasing its flow and caliber. In both cases, angiography after embolization demonstrated a 20%-45% increase in STA size, and doppler ultrasound indicated a 14%-50% increase in flow. Subsequently, both patients underwent successful STA-MCA bypass combined with encephalomyosynangiosis without complications. Of 167 STA-MCA bypasses performed by the senior author, embolization was performed in 7 unique patients on 9 sides. ECA embolization may be a beneficial adjunct when considering a direct bypass in the setting of a small STA. It can increase blood flow through the STA, making the operation technically easier and enhancing the patency of the bypass.
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Magnetic resonance imaging-graded hypothalamic compression in surgically treated adult craniopharyngiomas determining postoperative obesity. Neurosurg Focus 2010; 28:E3. [PMID: 20367360 DOI: 10.3171/2010.1.focus09303] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Obesity as a consequence of management of pediatric craniopharyngioma is a well-described phenomenon related to the degree of hypothalamic involvement. However, weight change and obesity have not been analyzed in adult patients. Therefore, the purpose of this study was 1) to evaluate the pattern of postoperative weight gain related to preoperative body mass index (BMI), 2) determine if postoperative weight gain is an issue in adult patients, and 3) develop an objective MR imaging grading system to predict risk of postoperative weight gain and obesity in adults treated for craniopharyngioma. METHODS The authors retrospectively screened 296 patients with known craniopharyngioma for the following inclusion criteria: pathologically confirmed craniopharyngioma, index surgery at the authors' institution, and operative weight and height recorded with at least 3 months of follow-up including body weight measurement. Patients aged 18 years or younger were excluded, yielding 28 cases for analysis. Cases of craniopharyngiomas were compared with age- and sex-matched controls (pituitary adenoma patients) to evaluate the pattern and significance of perioperative weight changes. RESULTS Mean age was 46 +/- 17 years at surgery, and 64% of the patients were male. Complete resection was achieved in 71% of cases. There was no correlation of preoperative BMI and postoperative weight gain testing in a linear model. Sixty-one percent and 46% of patients had postoperative weight gains greater than 4 and 9%, respectively. Comparing craniopharyngioma patients (cases) to age- and sex-matched controls, the preoperative BMIs were similar (p = 0.93) between cases (mean 28.9 [95% CI 30.9-26.9]) and controls (mean 29.3 [95% CI 31.9-26.7]). However, there was a trend to a greater mean postoperative weight change (percentage) in cases (10.1%) than in controls (5.6%) (p = 0.24). Hypothalamic T2 signal change and irregular contrast enhancement correlated and predicted higher-grade hypothalamic involvement. Furthermore, they can be used to objectively grade hypothalamic involvement as the authors propose. Progressive hypothalamic involvement correlated with larger postoperative weight gains (p = 0.022); however, hypothalamic involvement did not correlate with preoperative BMI (p = 0.5). CONCLUSIONS Postoperative weight gain in adult patients undergoing surgery for craniopharyngioma is a significant problem and correlates with hypothalamic involvement, as it does in pediatric patients. Finally, objective MR imaging criteria can be used to predict risk of postoperative weight gain and aid in grading of hypothalamic involvement.
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Does needle size matter? Patient experience of luteinising hormone-releasing hormone analogue injection. Prostate Cancer Prostatic Dis 2005; 8:66-8. [PMID: 15700050 DOI: 10.1038/sj.pcan.4500778] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To determine whether needle size influences a patient's perception of pain, 50 patients requiring hormonal manipulation for prostate cancer were blindfolded and randomised to receive two goserelin ('Zoladex') or two leuprorelin ('Prostap') injections, using 16- or 23-gauge needles, respectively. Median visual analogue scale pain scores for the first injections of goserelin and leuprorelin were below the level of clinical significance and were not statistically different. Mean administration time for goserelin was significantly shorter than for leuprorelin. In conclusion, there was no statistically significant difference in pain experienced on injection of goserelin and leuprorelin when patients were unaware of needle size.
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Computer-identified nuclear localization signal in exon 1A of the transporter DMT1 is essentially ineffective in nuclear targeting. J Neurosci Res 2004; 76:497-511. [PMID: 15114622 DOI: 10.1002/jnr.20112] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Divalent metal transporter 1 (DMT1; also called DCT1, Nramp2, or SLC11A2) has multiple isoforms that localize differently in many cell types. DMT1 +IRE species (encoded by mRNA with an iron-responsive element) are limited to the plasma membrane and cytosolic vesicles. In neural cells, -IRE isoforms of DMT1 (encoded by mRNA lacking an IRE) localize to the nucleus, plasma membrane, and cytosolic vesicles. In considering nuclear compartmentalization of -IRE isoforms, we hypothesized that the newly identified exon 1A in the N-terminus of this transporter might contain a nuclear localization signal. DNA constructs starting with exon 1A and ending with exons encoding alternative isoforms were made and transiently transfected into HEK293T and PC12 cells as well as rat sympathetic neurons. None of the constructs appeared in the nucleus despite the presence of exon 1A. Antibody specific for exon 1A was also used in both immunostaining and Western blots to investigate localization of exon 1A expressed both endogenously and ectopically in cells. Again, nuclear localization of DMT1 containing exon 1A was not observed. Our data suggest that exon 1A is neither sufficient nor necessary for DMT1 to appear in the nucleus.
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Abstract
There is little evidence in the literature regarding the effects of a carbon fiber insert on beam parameters with beam size variations. We demonstrated this effect and noted the magnitude of the change of surface dose induced. It was shown that use of the carbon fiber insert panel, despite providing minimal attenuation of the primary radiation, significantly decreased the skin-sparing effect. The magnitude of this decrease was relatively larger for smaller beam sizes. The surface dose was nearly 4 times as large when carbon was added to a 10 x 10-cm beam, and nearly double for a 40 x 40-cm beam.
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Cine MRI using steady state free precession in the radial long axis orientation is a fast accurate method for obtaining volumetric data of the left ventricle. J Magn Reson Imaging 2001; 14:685-92. [PMID: 11747024 DOI: 10.1002/jmri.10019] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
In this study we assessed the use of a steady state free precession (SSFP) cine sequence in a series of radially orientated long axis slices for the measurement of left ventricular volumes and mass. We validated the radial long axis approach in phantoms and ex vivo porcine hearts and applied it to normal volunteers and patients using the SSFP and turbo gradient-echo (TGE) sequences. High quality images were obtained for analysis, and the measured volumes with radial long axis SSFP sequence correlated well with short axis TGE and SSFP volumes (r > 0.98). The best interobserver agreement for left ventricular volumes was obtained using SSFP in the long axis radial orientation (variability < 2.3%). We conclude that this combination of sequence and scan orientation has intrinsic advantages for image analysis due to the improved contrast and the avoidance of errors associated with the basal slice in the short axis orientation.
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Asthma self-management: do patient education programs always have an impact? ARCHIVES OF INTERNAL MEDICINE 1999; 159:2422-8. [PMID: 10665890 DOI: 10.1001/archinte.159.20.2422] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND During the past 15 years, programs to improve self-management practices in adults with asthma have reported improvement in functional status and reduction of inappropriate use of health care services. However, these programs usually represent an ideal approach, applying multiple patient education methods. Consequently, when these programs are found to be efficacious, it is important to replicate the programs as well as to evaluate less complex methods that may be more appropriate for nonacademic health care settings. METHODS We compared the following 3 standardized self-management treatments in a randomized, controlled trial: (1) a replication of the self-management program developed at a university medical center that was previously shown to be efficacious; (2) a modified version of this program including only the core elements; and (3) a usual-care program. Outcome measures included medication and inhaler regimen adherence, asthma symptoms, respiratory illness, functional status, and use of health care resources. RESULTS All 3 groups improved on measures of respiratory illnesses, use of health care services, and functional status. Patients in both education groups did no better than the usual-care group. CONCLUSIONS The results are inconsistent with the results of the first asthma self-management study at this institution and with those of efficacy studies of similar programs. Two factors, selection of the patient population and historical changes in asthma treatment, most likely contributed to the lack of impact of the self-management programs. As a result of the improved standards for usual care due to both factors, the opportunity to effect patient outcomes was substantially reduced.
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"Productivity on the cheap"? The "more looms" experiment and the Lancashire weaving industry during the inter-war years. BUSINESS HISTORY 1999; 41:21-41. [PMID: 19455770 DOI: 10.1080/00076799900000343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Two major debates in the literature, productivity performance and the decline of the cotton industry, are joined in the analysis presented in this article on the attempts to raise productivity through the introduction of the more looms per weaver system in cotton weaving in the inter-war years. We find that the limited resultant changes were the outcome of understandable predisposition to maintain co-operative behaviour which meant that productivity enhancing schemes with long term potential were sacrificed for more modest schemes which preserved consensus in the short term.
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Abstract
Patients with tracheostomy tubes have altered motor and sensory functions that may decrease their swallowing efficiency. Failure to recognize disorders in deglutition may result in dangerous complications including aspiration and death. Assessment of dysphagia is especially important in the patient transferred from the intensive care unit to the ward--where resources are less abundant. We present six cases in which cuff deflation or change of tracheostomy tube were undertaken without documented swallowing assessment. In these cases each patient was found to be aspirating and required the cuff to be reinflated, or a cuffed tube to be reinstated when assessed by the multidisciplinary team. Dysphagia management in the patient with a tracheostomy should be approached from a multidisciplinary point of view so that appropriate decisions can be made regarding changes in management and the decannulation process.
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Abstract
PURPOSE Reviewers of the asthma research literature have called for improved questionnaires and other measures, particularly for assessing the severity of asthma. To help meet this need, standard multivariate and psychometric techniques were used with data from asthma patients to develop and evaluate a series of scaled questions. Since there is no "gold standard" for assessing asthma severity, we hope this analysis will help improve our ability to more precisely define these important parameters. PATIENTS AND METHODS Data were collected through interviews and review of clinic records for 199 adult patients with asthma from a university clinic population. For evaluating the severity of asthma, eight scales assessed asthma duration, the incidence of asthma symptoms, the extent to which asthma is an inconvenience to patients, the incidence of respiratory diseases, medication regimens, medication side effects, and health care utilization. Forced expiratory volume in 1 second as a percentage of predicted normal was included as an objective measure of pulmonary function. A physician rating scale assessed the severity of the underlying disease, not the severity of a particular episode, as either (1) mild (infrequent attacks with interim symptomatic treatment), (2) moderate (more frequent attacks with continuous daily treatment), and (3) severe (continuous symptom with continuous multiple drug regimen, including some systemic steroids). RESULTS In the current analysis of data from adult asthma patients, the scales correlated positively with a physician judgment scale. Factor analysis with an oblique rotation yielded three factors that provided a concise summary of asthma severity. We have named the factors (A) Symptom Intensity, (B) Airflow Impairment, and (C) Management Intensity. CONCLUSION Asthma severity appears to be multidimensional rather than unidimensional, including at least three components. The physician rating scale, in combination with measures of the three identified factors, could easily be included in other asthma research protocols to provide a standard, brief assessment of asthma severity and might thus promote greater comparability among studies.
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Myosin light chain kinase is expressed in neurons and glia: immunoblotting and immunocytochemical studies. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1992; 14:27-34. [PMID: 1323015 DOI: 10.1016/0169-328x(92)90006-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The contractile protein myosin is thought to subserve motility-related functions in a wide range of eukaryotic non-muscle cells including both neurons and glia. To determine if the Ca2+/calmodulin-dependent enzyme, myosin light chain kinase (MLCK) is involved in the regulation of neural myosin we investigated the presence and localization of MLCK in a variety of neural tissues by immunoblotting and immunocytochemistry. A specific immunoreactive protein (M(r) = 146,000) was detected in blotted homogenates from many regions of rat brain and from primary cultures of either astrocytes or cerebellar granule cells grown in the absence of other cell types. At the light microscopic level, MLCK-immunoreactivity was evident in many regions of rat brain, as well as in the cultured astrocytes and cerebellar granule cells. MLCK-immunoreactivity was observed to be largely cytosolic in astrocytes but with a proportion associated with the cytoskeleton. In the cerebellar granule cells immunoreactivity was present in neuronal processes as well as somata. The detection of MLCK in neural cells suggests that MLCK-catalyzed myosin phosphorylation may couple changes in intracellular calcium concentrations to motility-related functions of neurons and glia.
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Abstract
This article examines the role of innervation in regulating expression of acetylcholinesterase (AchE), butyrylcholinesterase (BuchE), and the muscarinic acetylcholine receptor (mAchR) in avian heart. Two distinct approaches are taken. The first approach examines the relation between the onsets of parasympathetic and sympathetic innervation and the appearance of AchE and BuchE. All molecular forms of AchE and BuchE are present in early embryonic chick heart well before the onset of parasympathetic and sympathetic innervation. These molecular forms are characterized by sedimentation coefficients of 4.5S, 11S, 15S, and 19S. With further development, the amounts of AchE fall; the reductions in AchE parallel the onset of functional parasympathetic innervation. The amounts of BuchE increase progressively throughout embryonic development, independent of autonomic innervation, and in mature chick heart predominate over the much less abundant amounts of AchE. The 15S and 19S forms of AchE in heart are lost during early embryogenesis but reappear in skeletal muscle during later embryogenesis. The second approach examines the influence of vagotomy and sympathetic denervation of 8-day-old chick myocardium on expression of the molecular forms of AchE, BuchE, mAchR, and beta-adrenergic receptors. The amounts of AchE and BuchE molecular forms in avian heart are not measurably influenced by bilateral vagotomy for a duration of 4 days, unilateral vagotomy for a duration of 25 days, or sympathetic denervation. A measurable upregulation is observed in muscarinic receptors (35-46%) after vagotomy but not sympathectomy and in beta-adrenergic receptors (29%) after sympathectomy but not vagotomy. In all cases, results in atria and ventricles are nearly identical. The present results indicate that expression of AchE in the myocardium is unique and different from that in skeletal muscle and not directly linked with autonomic innervation.
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