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Gregory CD. Hijacking homeostasis: Regulation of the tumor microenvironment by apoptosis. Immunol Rev 2023; 319:100-127. [PMID: 37553811 PMCID: PMC10952466 DOI: 10.1111/imr.13259] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 07/18/2023] [Indexed: 08/10/2023]
Abstract
Cancers are genetically driven, rogue tissues which generate dysfunctional, obdurate organs by hijacking normal, homeostatic programs. Apoptosis is an evolutionarily conserved regulated cell death program and a profoundly important homeostatic mechanism that is common (alongside tumor cell proliferation) in actively growing cancers, as well as in tumors responding to cytotoxic anti-cancer therapies. Although well known for its cell-autonomous tumor-suppressive qualities, apoptosis harbors pro-oncogenic properties which are deployed through non-cell-autonomous mechanisms and which generally remain poorly defined. Here, the roles of apoptosis in tumor biology are reviewed, with particular focus on the secreted and fragmentation products of apoptotic tumor cells and their effects on tumor-associated macrophages, key supportive cells in the aberrant homeostasis of the tumor microenvironment. Historical aspects of cell loss in tumor growth kinetics are considered and the impact (and potential impact) on tumor growth of apoptotic-cell clearance (efferocytosis) as well as released soluble and extracellular vesicle-associated factors are discussed from the perspectives of inflammation, tissue repair, and regeneration programs. An "apoptosis-centric" view is proposed in which dying tumor cells provide an important platform for intricate intercellular communication networks in growing cancers. The perspective has implications for future research and for improving cancer diagnosis and therapy.
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Affiliation(s)
- Christopher D. Gregory
- Centre for Inflammation ResearchInstitute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarterEdinburghUK
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Morana O, Wood W, Gregory CD. The Apoptosis Paradox in Cancer. Int J Mol Sci 2022; 23:ijms23031328. [PMID: 35163253 PMCID: PMC8836235 DOI: 10.3390/ijms23031328] [Citation(s) in RCA: 100] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 02/01/2023] Open
Abstract
Cancer growth represents a dysregulated imbalance between cell gain and cell loss, where the rate of proliferating mutant tumour cells exceeds the rate of those that die. Apoptosis, the most renowned form of programmed cell death, operates as a key physiological mechanism that limits cell population expansion, either to maintain tissue homeostasis or to remove potentially harmful cells, such as those that have sustained DNA damage. Paradoxically, high-grade cancers are generally associated with high constitutive levels of apoptosis. In cancer, cell-autonomous apoptosis constitutes a common tumour suppressor mechanism, a property which is exploited in cancer therapy. By contrast, limited apoptosis in the tumour-cell population also has the potential to promote cell survival and resistance to therapy by conditioning the tumour microenvironment (TME)-including phagocytes and viable tumour cells-and engendering pro-oncogenic effects. Notably, the constitutive apoptosis-mediated activation of cells of the innate immune system can help orchestrate a pro-oncogenic TME and may also effect evasion of cancer treatment. Here, we present an overview of the implications of cell death programmes in tumour biology, with particular focus on apoptosis as a process with "double-edged" consequences: on the one hand, being tumour suppressive through deletion of malignant or pre-malignant cells, while, on the other, being tumour progressive through stimulation of reparatory and regenerative responses in the TME.
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Gregory CD, Paterson M. An apoptosis-driven 'onco-regenerative niche': roles of tumour-associated macrophages and extracellular vesicles. Philos Trans R Soc Lond B Biol Sci 2018; 373:rstb.2017.0003. [PMID: 29158317 PMCID: PMC5717442 DOI: 10.1098/rstb.2017.0003] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/05/2017] [Indexed: 12/31/2022] Open
Abstract
The cell-death programme, apoptosis, is well established as a tumour suppressor mechanism. Paradoxically, high levels of apoptosis in tumours are closely coupled with poor prognosis. Indeed, where it has been studied, cell loss is a striking feature of high-grade cancers, illustrating the importance of considering malignant disease as an imbalance between cell gain and cell loss that favours cell gain rather than as a unidirectional disorder of cell gain alone. In addition to orchestrating cell loss, apoptosis can signal regenerative responses—for example compensatory proliferation—in neighbouring cells. Accumulating evidence suggests that normal tissue repair and regenerative processes are hijacked in the malignant tissue microenvironment such that cancer may be likened to a ‘wound that fails to stop repairing’. We have proposed that a critical requirement for the successful growth, progression and re-growth of malignant tumours is a complex milieu, conceptually termed the ‘onco-regenerative niche’, which is composed, in addition to transformed neoplastic cells, of a network of normal cells and factors activated as if in tissue repair and regeneration. Our work is based around the hypothesis that tumour cell apoptosis, macrophage activation and endothelial activation are key, interlinked elements of the onco-regenerative niche and that apoptotic tumour cell–derived extracellular vesicles provide critical intercellular communication vehicles of the niche. In aggressive B-cell lymphoma, tumour cell apoptosis promotes both angiogenesis and the accumulation of pro-tumour macrophages in the lymphoma microenvironment. Furthermore, apoptotic lymphoma-derived extracellular vesicles have potent pro-tumour potential. These findings have important implications for the roles of apoptosis in regulation of malignant diseases and for the efficacy of apoptosis-inducing anti-cancer therapies. This article is part of the discussion meeting issue ‘Extracellular vesicles and the tumour microenvironment’.
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Affiliation(s)
- Christopher D Gregory
- MRC Centre for Inflammation Research, University of Edinburgh College of Medicine and Veterinary Medicine, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Margaret Paterson
- MRC Centre for Inflammation Research, University of Edinburgh College of Medicine and Veterinary Medicine, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
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Li Y, Qian Z, Xu K, Wang K, Fan X, Li S, Jiang T, Liu X, Wang Y. MRI features predict p53 status in lower-grade gliomas via a machine-learning approach. NEUROIMAGE-CLINICAL 2017. [PMID: 29527478 PMCID: PMC5842645 DOI: 10.1016/j.nicl.2017.10.030] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background P53 mutation status is a pivotal biomarker for gliomas. Here, we developed a machine-learning model to predict p53 status in lower-grade gliomas based on radiomic features extracted from conventional magnetic resonance (MR) images. Methods Preoperative MR images were retrospectively obtained from 272 patients with primary grade II/III gliomas. The patients were randomly allocated in a 2:1 ratio to a training (n = 180) or validation (n = 92) set. A total of 431 radiomic features were extracted from each patient. The lest absolute shrinkage and selection operator (LASSO) method was used for feature selection and radiomic signature construction. Subsequently, a machine-learning model to predict p53 status was established using the selected features and a Support Vector Machine classifier. The predictive performance of all individual features and the model was calculated using receiver operating characteristic curves in both the training and validation sets. Results The p53-related radiomic signature was built using the LASSO algorithm; this procedure consisted of four first-order statistics or related wavelet features (including Maximum, Median, Minimum, and Uniformity), a shape and size-based feature (Spherical Disproportion), and ten textural features or related wavelet features (including Correlation, Run Percentage, and Sum Entropy). The prediction accuracies based on the area under the curve were 89.6% in the training set and 76.3% in the validation set, which were better than individual features. Conclusions These results demonstrate that MR image texture features are predictive of p53 mutation status in lower-grade gliomas. Thus, our procedure can be conveniently used to facilitate presurgical molecular pathological diagnosis. We established a p53-related radiomic signature in lower-grade gliomas based on LASSO algorithm. We developed a machine-learning model using the radiomic signature and a support vector machine. P53 mutation status of lower-grade gliomas was predicted effectively based on our machine-learning model.
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Affiliation(s)
- Yiming Li
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Zenghui Qian
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Kaibin Xu
- Chinese Academy of Sciences, Institute of Automation, Beijing, China
| | - Kai Wang
- Department of Neuroradiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Xing Fan
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Shaowu Li
- Neurological Imaging Center, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Tao Jiang
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China; Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; Center of Brain Tumor, Beijing Institute for Brain Disorders, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China.
| | - Xing Liu
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.
| | - Yinyan Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
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Teng Y, Dong YC, Liu Z, Zou Y, Xie H, Zhao Y, Su J, Cao F, Jin H, Ren H. DNA methylation-mediated caspase-8 downregulation is associated with anti-apoptotic activity and human malignant glioma grade. Int J Mol Med 2017; 39:725-733. [DOI: 10.3892/ijmm.2017.2881] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 01/27/2017] [Indexed: 11/05/2022] Open
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Kumar S. P53 induction accompanying G2/M arrest upon knockdown of tumor suppressor HIC1 in U87MG glioma cells. Mol Cell Biochem 2014; 395:281-90. [PMID: 24992983 DOI: 10.1007/s11010-014-2137-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 06/17/2014] [Indexed: 10/25/2022]
Abstract
Hypermethylated in cancer 1 (HIC1) is a novel tumor suppressor gene (tsg) frequently silenced by epigenetic modification, predominantly by methylation in different tumors. HIC1 functionally co-operates with p53 in cultured cells as well as in transgenic animals to suppress tumors and has binding site on its promoter. Its over expression often leads to cell cycle arrests. Although HIC1 proven to have role as tsg, its regulation to cell cycle and dependency upon p53 is grossly unknown. In this study, we investigated the role of HIC1 in cell cycle and proliferation of glioma cell line U87MG which has wild type p53, in both serum-containing and serum-deprived medium. Microscopic analysis and MTT assay showed reduced cell number and rate of proliferation upon HIC1 knock down compared to control siRNA (p = 0.025) and untreated cells (p = 0.03) in serum-containing medium and serum-free medium (p = 0.014 vs control siRNA; p = 0.018 vs untreated cells). Cell cycle analysis revealed an arrest at G2/M phase of cell cycle with no demonstrable increase in apoptosis with both medium. An increased expression of p53 concomitant with HIC1 knockdown was observed. Furthermore P21, a p53 responsive gene, along with p27 was significantly increased in comparison with controls. Our results demonstrated an important role of HIC1 for the normal progression of cell cycle, and at molecular level, it could affect the homeostasis of p53 as well as number of cell cycle-related genes, which may or may not be directly linked to p53.
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Affiliation(s)
- Sanjay Kumar
- Biomolecular Science Centre, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Bld 20, 4110 Libra Drive, Orlando, FL, 32816, USA,
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Valdés PA, Kim A, Brantsch M, Niu C, Moses ZB, Tosteson TD, Wilson BC, Paulsen KD, Roberts DW, Harris BT. δ-aminolevulinic acid-induced protoporphyrin IX concentration correlates with histopathologic markers of malignancy in human gliomas: the need for quantitative fluorescence-guided resection to identify regions of increasing malignancy. Neuro Oncol 2011; 13:846-56. [PMID: 21798847 DOI: 10.1093/neuonc/nor086] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Extent of resection is a major goal and prognostic factor in the treatment of gliomas. In this study we evaluate whether quantitative ex vivo tissue measurements of δ-aminolevulinic acid-induced protoporphyrin IX (PpIX) identify regions of increasing malignancy in low- and high-grade gliomas beyond the capabilities of current fluorescence imaging in patients undergoing fluorescence-guided resection (FGR). Surgical specimens were collected from 133 biopsies in 23 patients and processed for ex vivo neuropathological analysis: PpIX fluorimetry to measure PpIX concentrations (C(PpIX)) and Ki-67 immunohistochemistry to assess tissue proliferation. Samples displaying visible levels of fluorescence showed significantly higher levels of C(PpIX) and tissue proliferation. C(PpIX) was strongly correlated with histopathological score (nonparametric) and tissue proliferation (parametric), such that increasing levels of C(PpIX) were identified with regions of increasing malignancy. Furthermore, a large percentage of tumor-positive biopsy sites (∼40%) that were not visibly fluorescent under the operating microscope had levels of C(PpIX) greater than 0.1 µg/mL, which indicates that significant PpIX accumulation exists below the detection threshold of current fluorescence imaging. Although PpIX fluorescence is recognized as a visual biomarker for neurosurgical resection guidance, these data show that it is quantitatively related at the microscopic level to increasing malignancy in both low- and high-grade gliomas. This work suggests a need for improved PpIX fluorescence detection technologies to achieve better sensitivity and quantification of PpIX in tissue during surgery.
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Affiliation(s)
- Pablo A Valdés
- Dartmouth Medical School, Dartmouth College, Hanover, New Hampshire, USA
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Aberrant signaling pathways in glioma. Cancers (Basel) 2011; 3:3242-78. [PMID: 24212955 PMCID: PMC3759196 DOI: 10.3390/cancers3033242] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 08/01/2011] [Accepted: 08/03/2011] [Indexed: 12/30/2022] Open
Abstract
Glioblastoma multiforme (GBM), a WHO grade IV malignant glioma, is the most common and lethal primary brain tumor in adults; few treatments are available. Median survival rates range from 12–15 months. The biological characteristics of this tumor are exemplified by prominent proliferation, active invasiveness, and rich angiogenesis. This is mainly due to highly deregulated signaling pathways in the tumor. Studies of these signaling pathways have greatly increased our understanding of the biology and clinical behavior of GBM. An integrated view of signal transduction will provide a more useful approach in designing novel therapies for this devastating disease. In this review, we summarize the current understanding of GBM signaling pathways with a focus on potential molecular targets for anti-signaling molecular therapies.
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Chaponis D, Barnes JW, Dellagatta JL, Kesari S, Fast E, Sauvageot C, Panagrahy D, Greene ER, Ramakrishna N, Wen PY, Kung AL, Stiles C, Kieran MW. Lonafarnib (SCH66336) improves the activity of temozolomide and radiation for orthotopic malignant gliomas. J Neurooncol 2011; 104:179-89. [PMID: 21246394 DOI: 10.1007/s11060-010-0502-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2010] [Accepted: 12/13/2010] [Indexed: 11/29/2022]
Abstract
Malignant gliomas are highly lethal tumors resistant to current therapies. The standard treatment modality for these tumors, surgical resection followed by radiation therapy and concurrent temozolomide, has demonstrated activity, but development of resistance and disease progression is common. Although oncogenic Ras mutations are uncommon in gliomas, Ras has been found to be constitutively activated through the action of upstream signaling pathways, suggesting that farnesyltransferase inhibitors may show activity against these tumors. We now report the in vitro and orthotopic in vivo results of combination therapy using radiation, temozolomide and lonafarnib (SCH66336), an oral farnesyl transferase inhibitor, in a murine model of glioblastoma. We examined the viability, proliferation, farnesylation of H-Ras, and activation of downstream signaling of combination-treated U87 cells in vitro. Lonafarnib alone or in combination with radiation and temozolomide had limited tumor cell cytotoxicity in vitro although it did demonstrate significant inhibition in tumor cell proliferation. In vivo, lonafarnib alone had a modest ability to inhibit orthotopic U87 tumors, radiation and temozolomide demonstrated better inhibition, while significant anti-tumor activity was found with concurrent lonafarnib, radiation, and temozolomide, with the majority of animals demonstrating a decrease in tumor volume. The use of tumor neurospheres derived from freshly resected adult human glioblastoma tissue was relatively resistant to both temozolomide and radiation therapy. Lonafarnib had a significant inhibitory activity against these neurospheres and could potentate the activity of temozolomide and radiation. These data support the continued research of high grade glioma treatment combinations of farnesyl transferase inhibitors, temozolomide, and radiation therapy.
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Affiliation(s)
- Deviney Chaponis
- Department of Pediatric Hematology/Oncology, Dana-Farber Cancer Institute and Children's Hospital Boston, Boston, MA, USA
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Kang HC, Kim CY, Han JH, Choe GY, Kim JH, Kim JH, Kim IA. Pseudoprogression in patients with malignant gliomas treated with concurrent temozolomide and radiotherapy: potential role of p53. J Neurooncol 2010; 102:157-62. [PMID: 20632071 DOI: 10.1007/s11060-010-0305-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 07/07/2010] [Indexed: 01/19/2023]
Abstract
We investigated pseudoprogression (psPD) in patients with malignant gliomas treated with radiotherapy (RT) and maintenance temozolomide (TMZ) in terms of incidence, outcomes, and predictive and prognostic factors. We evaluated p53 overexpression by immunohistochemical analysis of thirty-five tumor samples as a predictor for psPD. The time to progression and overall survival were compared between subgroups, psPD versus early progression (ePD) versus nonprogression (nonPD). Eight patients developed psPD among eighteen patients with lesion enlargement at the first MRI scan, and the others were classified as ePD. The remaining stable or improved patients were classified as nonPD. All patients with psPD were alive at last follow-up (median follow-up period was 12 months; range 5.8-58.5 months). Overall survival of psPD patients was significantly higher than ePD patients (P < 0.01). There was no significant survival difference between the psPD group and nonPD group (P = 0.25). Seven (87.5%) of eight tumors with psPD showed p53 overexpression, as compared to 3 (30%) of the ten tumors with ePD (P = 0.03). Our study indicates that psPD following chemoradiotherapy with TMZ is associated with significantly better overall survival compared to that of ePD, and is comparable to nonPD group. Overexpression of p53 was identified as a potential biomarker for predicting the development of psPD.
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Affiliation(s)
- Hyun-Cheol Kang
- Department of Radiation Oncology, Seoul National University Bundang Hospital, 300 Gumidong Seongnamsi, Kyeonggido 463-707, Republic of Korea
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Kremer P, Fardanesh M, Ding R, Pritsch M, Zoubaa S, Frei E. Intraoperative fluorescence staining of malignant brain tumors using 5-aminofluorescein-labeled albumin. Neurosurgery 2009; 64:ons53-60; discussion ons60-1. [PMID: 19240573 DOI: 10.1227/01.neu.0000335787.17029.67] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The newly developed conjugate 5-aminofluorescein (AFL)-human serum albumin (HSA) was investigated in a clinical trial for fluorescence-guided surgery of malignant brain tumors to assess its efficacy and tolerability. METHODS AFL, covalently linked to human serum albumin at a molar ratio of 1:1, was administered intravenously 0.5 to 4 days before surgery at 0.5 or 1.0 mg/kg of body weight to 13 patients aged 38 to 71 years who were suspected of having malignant gliomas. Fluorescence guidance using a 488-nm argon laser was performed during surgery at will. The extent of tumor resection was verified by early postoperative magnetic resonance imaging. Fluorescent and nonfluorescent samples were collected for neuropathology. Blood samples for laboratory and pharmacokinetic analyses were taken over the course of 4 weeks. RESULTS Fluorescence staining of tumor tissue was bright in 11 patients (84%), resulting in complete resection of fluorescent tumor tissue in 9 patients (69%). In 2 patients, residual fluorescent tumor tissue was also confirmed by magnetic resonance imaging. Neither bleaching nor penetration of AFL-HSA into the surrounding brain edema or into necrotic tissue was seen. The agreement between fluorescence and histopathology in tumor samples and samples of the tumor border was 83.3%. There were no toxic side effects. The quality of fluorescence was independent of the dose administered. The optimal time for surgery is between 1 and 4 days after AFL-HSA administration. CONCLUSION Tumor fluorescence using AFL-HSA made fluorescence-guided brain tumor resection possible, demonstrating that albumin is a suitable carrier system for selective targeting of aminofluorescein into malignant gliomas.
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Affiliation(s)
- Paul Kremer
- Department of Neurosurgery, Kopfklinikum, University of Heidelberg, Heidelberg, Germany.
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Wiewrodt D, Nagel G, Dreimüller N, Hundsberger T, Perneczky A, Kaina B. MGMT in primary and recurrent human glioblastomas after radiation and chemotherapy and comparison with p53 status and clinical outcome. Int J Cancer 2008; 122:1391-9. [PMID: 18000822 DOI: 10.1002/ijc.23219] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) plays a pivotal role in alkylating drug resistance. Here, we determined MGMT activity in primary and recurrent glioblastomas (GBM, WHO grade IV) of patients who received radiation therapy (RT) or RT plus chemotherapy with alkylating agents (temozolomide, chloroethylnitrosoureas). The mean MGMT activity of untreated GBM was 37 +/- 45 (range 0-205) fmol/mg proteins. In the 1st, 2nd and 3rd recurrences, MGMT activity increased from 66 +/- 50 (13-194) to 68 +/- 44 (14-143) and 182 +/- 163 (64-423) fmol/mg protein, respectively. Comparing patients who received RT only with RT plus chemotherapy, a significant increase of MGMT in 1st recurrences was only found after treatment with RT plus chemotherapy, indicating either selection of MGMT expressing cells or induction of the MGMT gene by alkylating agents. The p53 status was not significantly related to the MGMT expression level, although a trend for lower MGMT activity in p53 positively stained tumors was observed. Patients expressing MGMT activity of <or=30 fmol/mg protein in the pretreatment tumor had a significant better therapeutic response than patients expressing MGMT above this level, which was shown by Kaplan-Meyer curves and the recurrence free interval after primary tumor resection. In patients who received RT only, this correlation was not found. The data revealed a threshold of MGMT expression (30 fmol/mg protein) below which patients respond better to alkylating agents. Therefore, determination of MGMT activity in the primary tumor appears to be useful in predicting the outcome of GBM therapy.
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Pope LZB, Serapião MJ, Serapião CJ, Oliveira MMST, Benites Filho PR, Gugelmin ES, Bleggi-Torres LF. Glioblastoma pediátrico: estudo clínico patológico de 12 casos com imunoistoquímica para proteína p53. ARQUIVOS DE NEURO-PSIQUIATRIA 2007; 65:1056-61. [DOI: 10.1590/s0004-282x2007000600030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Accepted: 08/14/2007] [Indexed: 11/22/2022]
Abstract
Glioblastoma é um dos tumores primários mais letais do sistema nervoso central (SNC). Apesar dos significativos progressos, há poucas análises em crianças. Com o objetivo de avaliar localização, idade, sexo, sobrevida e imunoistoquímica para proteína p53, foram coletados casos de glioblastomas pediátricos do "Banco de Tumores do SNC de Curitiba", durante 1987-2003 e do Hospital Municipal Jesus, Rio de Janeiro, de 1970 a 1988. Doze preencheram os critérios de inclusão. A idade variou até 12 anos (média 7), sendo sete do sexo feminino e cinco do masculino. A sobrevida média foi 7,9 meses. Localizavam-se em hemisférios cerebrais (58,4%), mesencéfalo e tronco (33,3%) e um no cerebelo. A imunoistoquímica demonstrou p53 positivo em 9 (75%). Em conclusão, glioblastoma tem comportamento semelhante entre crianças e adultos, sendo nestas menos freqüentes. Acomete hemisférios cerebrais com maior freqüência que estruturas infratentoriais, mostrando alta sensitividade com a imunomarcação para proteína p53, sendo nestes casos mais agressivos, com menor sobrevida.
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Vlodavsky E, Soustiel JF. Immunohistochemical expression of peripheral benzodiazepine receptors in human astrocytomas and its correlation with grade of malignancy, proliferation, apoptosis and survival. J Neurooncol 2006; 81:1-7. [PMID: 16868661 DOI: 10.1007/s11060-006-9199-9] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2006] [Accepted: 05/15/2006] [Indexed: 11/29/2022]
Abstract
Peripheral benzodiazepine receptors (PBR) are widely distributed in peripheral tissues, astrocytes, and microglia of the brain. They are involved in apoptosis, proliferation, and many other processes, such as steroidogenesis in adrenal glands, male and female gonads, biological adaptation to stress, etc. It has been established that the expression of PBR in astrocytomas is higher than in the normal brain. The goal of this study was to explore the correlation of the immunohistochemical expression of PBR in astrocytomas with the grade of malignancy and rates of apoptosis, proliferation and survival. In 130 cases of astrocytomas (25 grade I, 25 grade II, 20 grade III, 60 grade IV), paraffin sections were stained immunohistochemically for PBR and MIB-1(Ki-67). TUNEL assay was used for evaluation of apoptosis. It was found that the intensity and extent of staining for PBR had a strong direct correlation with the grade of malignancy of the tumor, along with proliferative and apoptotic indices. The highest expression of PBR was in glioblastomas grade IV, especially around areas of necrosis. There was a strong negative correlation between PBR expression and survival. The results of this study may be applied in the pathological diagnosis of astrocytomas as an additional clue in establishing tumor grade; they may be used in the imaging of astrocytomas, both for diagnosis and follow-up, by the application of positron emission tomography scanning with PBR specific ligands. Targeting of PBR in high-grade gliomas may be a promising approach, achieving more specific anti-tumor effect.
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Affiliation(s)
- Eugene Vlodavsky
- Pathology Institute, Rambam Medical Center and Faculty of Medicine, Technion-Israel Institute of Technology, POB 9602, Haifa, Israel.
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