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Lamprou I, Kakouratos C, Tsolou A, Pavlidis P, Xanthopoulou ET, Nanos C, Tsaroucha A, Sivridis E, Giatromanolaki A, Koukourakis MI. Lipophagy-related protein perilipin-3 (PLIN3) and resistance of prostate cancer to radiotherapy. Int J Radiat Oncol Biol Phys 2022; 113:401-414. [PMID: 35121129 DOI: 10.1016/j.ijrobp.2022.01.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 12/17/2021] [Accepted: 01/23/2022] [Indexed: 11/19/2022]
Abstract
PURPOSE Radiotherapy is a principal treatment modality for localized and locally advanced prostate cancer (PCa). Metabolic alterations, including lipid metabolism, may reduce treatment efficacy resulting in tumor relapse and poor therapeutic outcome. In the current study, we investigated the role of the lipophagy-related protein perilipin-3 (PLIN3) and the lysosomal acid lipase (LAL) in PCa response to radiotherapy. METHODS AND MATERIALS We explored the in vitro and xenograft (in NOD.SCID and R2G2 mice) response to radiation of either PLIN3-depleted or LAL-depleted hormone-refractory (DU145, PC3), and hormone-responsive 22Rv1 PCa cell lines. Moreover, we evaluated the clinical role of PLIN3 and LAL protein expression in a series of PCa tissue specimens from patients treated with radical radiotherapy. RESULTS In vitro and in vivo experiments showed reduced proliferation and strong radiosensitization of all studied PCa cell lines upon PLIN3 depletion. In vivo experiments demonstrated the significantly augmented radiotherapy efficacy upon PLIN3 depletion, resulting in extensive tissue necrosis. PLIN3 overexpression in tissue specimens was correlated with increased MIB1 proliferation index, increased autophagy flux, reduced response to radiotherapy and poor prognosis. The impact of LAL depletion on radiotherapy was of lesser importance. CONCLUSIONS Assessment of PLIN3 expression may identify subgroups of PCa patients less responsive to radiotherapy, and at high risk of relapse post irradiation. Whether radiotherapy efficacy may be enhanced by concurrent autophagy or PLIN3 inhibition in this sub-group of patients demands clinical evaluation.
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Affiliation(s)
| | | | | | | | | | | | | | - Efthimios Sivridis
- Department of Pathology, Democritus University of Thrace, Alexandroupolis, Greece
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Kakouratos C, Kalamida D, Lamprou I, Xanthopoulou E, Nanos C, Giatromanolaki A, Koukourakis MI. Apalutamide radio-sensitisation of prostate cancer. Br J Cancer 2021; 125:1377-1387. [PMID: 34471256 PMCID: PMC8575888 DOI: 10.1038/s41416-021-01528-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 07/30/2021] [Accepted: 08/11/2021] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTION The combination of radiotherapy with bicalutamide is the standard treatment of prostate cancer patients with high-risk or locally advanced disease. Whether new-generation anti-androgens, like apalutamide, can improve the radio-curability of these patients is an emerging challenge. MATERIALS AND METHODS We comparatively examined the radio-sensitising activity of apalutamide and bicalutamide in hormone-sensitive (22Rv1) and hormone-resistant (PC3, DU145) prostate cancer cell lines. Experiments with xenografts were performed for the 22Rv1 cell line. RESULTS Radiation dose-response viability and clonogenic assays showed that apalutamide had a stronger radio-sensitising activity for all three cell lines. Confocal imaging for γΗ2Αx showed similar DNA double-strand break repair kinetics for apalutamide and bicalutamide. No difference was noted in the apoptotic pathway. A striking cell death pattern involving nuclear karyorrhexis and cell pyknosis in the G1/S phase was exclusively noted when radiation was combined with apalutamide. In vivo experiments in SCID and R2G2 mice showed significantly higher efficacy of radiotherapy (2 and 4 Gy) when combined with apalutamide, resulting in extensive xenograft necrosis. CONCLUSIONS In vitro and in vivo experiments support the superiority of apalutamide over bicalutamide in combination with radiotherapy in prostate cancer. Clinical studies are encouraged to show whether replacement of bicalutamide with apalutamide may improve the curability rates.
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Affiliation(s)
- Christos Kakouratos
- grid.12284.3d0000 0001 2170 8022Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Dimitra Kalamida
- grid.12284.3d0000 0001 2170 8022Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Ioannis Lamprou
- grid.12284.3d0000 0001 2170 8022Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Erasmia Xanthopoulou
- grid.12284.3d0000 0001 2170 8022Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Christos Nanos
- grid.12284.3d0000 0001 2170 8022Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Alexandra Giatromanolaki
- grid.12284.3d0000 0001 2170 8022Department of Pathology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Michael I. Koukourakis
- grid.12284.3d0000 0001 2170 8022Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
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Mahdavi BF, Taheri A, Hejazi SH, Talebi A, Shokrani P. A protocol for irradiation of cell lines cultured in multi-well plates: effect of air inhomogeneity on irradiated cell survival. Int J Radiat Biol 2019; 95:1543-1546. [PMID: 31550183 DOI: 10.1080/09553002.2019.1642541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Introduction: In multi-well cell culture plates, wells are bordered by air cavities. The air cavity inhomogeneities can reduce the amount of delivered dose. In this study, the effect of these cavities on cell survival was investigated.Materials and methods: A special phantom was designed to house the plates and air cavities were filled by water equivalent materials. Cultured melanoma cells were irradiated using 6MV photon for 200 cGy. MTT and clonogenic assay tests were used to evaluate cell survival.Results: Results of MTT assay showed mean survival percentage for irradiated cells in the first group, i.e. plates with air cavities, was 18.9% higher than the second group with air cavities filled with paraffin. Clonogenic assay results showed a maximum of 37% difference in the mean of number of colonies between the first group and the second group (p value < .05).Conclusions: The presence of air cavities in multi-well cell culture plates reduced radiation cell kill by up to 37%. To ensure the accuracy of delivered dose, it is necessary to replace the air cavities as well as the air surrounding the plates by a water equivalent material.
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Affiliation(s)
- Bibi Fatemeh Mahdavi
- Department of Medical Physics and Medical Engineering, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Azade Taheri
- Department of Pharmaceutics, Novel Drug Delivery Systems Research Center, Faculty of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Seyed Hossein Hejazi
- Department of Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ardeshir Talebi
- Department of Pathology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Parvaneh Shokrani
- Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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Claridge Mackonis E, Hammond L, Esteves AIS, Suchowerska N. Radiation dosimetry in cell biology: comparison of calculated and measured absorbed dose for a range of culture vessels and clinical beam qualities. Int J Radiat Biol 2018; 94:150-156. [PMID: 29254418 DOI: 10.1080/09553002.2018.1419304] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE Cell culture studies are frequently used to evaluate the effects of cancer treatments such as radiotherapy, hormone therapy, chemotherapy, nanoparticle enhancement, and to determine any synergies between the treatments. To achieve valid results, the absorbed dose of each therapy needs to be well known and controlled. In this study, we aim to determine the uncertainty associated with radiation exposure in different experimental conditions. MATERIALS AND METHODS We have performed an in-depth evaluation of the absorbed dose and dose distribution that would be delivered to a cell sample when cultivated in a number of the more popular designs of culture vessels. We focus on exposure to two beam types: a kilovoltage x-ray beam and a megavoltage photon beam, both of which are routinely used to treat cancer patients in the clinical environment. CONCLUSIONS Our results identify large variations of up to 16% in the absorbed dose across multi-well culture plates, which if ignored in radiobiological experiments, have the potential to lead to erroneous conclusions.
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Affiliation(s)
| | - Lauren Hammond
- a Department of Radiation Oncology , Chris O'Brien Lifehouse , Camperdown , Australia
| | - Ana I S Esteves
- a Department of Radiation Oncology , Chris O'Brien Lifehouse , Camperdown , Australia.,b School of Physics , The University of Sydney , Camperdown , Australia
| | - Natalka Suchowerska
- a Department of Radiation Oncology , Chris O'Brien Lifehouse , Camperdown , Australia.,b School of Physics , The University of Sydney , Camperdown , Australia
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Abstract
Objective: Glioblastoma is the most common primary brain tumor in adults and one of the most lethal human tumors. It constitutes a unique non-metastasizing human tumor model with high resistance to radiotherapy and chemotherapy. The current study investigates the association between autophagic flux and glioblastoma cell resistance. Methods: The expression kinetics of autophagy- and lysosome-related proteins following exposure of two glioblastoma cell lines (T98 and U87) to clinically relevant radiation doses was examined. Then, the response of cells resistant to radiotherapy and chemotherapy was investigated after silencing of LC3A, LC3B, and TFEB genes in vitro and in vivo.
Results: Following irradiation with 4 Gy, the relatively radioresistant T98 cells exhibited enhanced autophagic flux. The more radiosensitive U87 cell line suffered a blockage of autophagic flux. Silencing of LC3A, LC3B, and TFEB genes in vitro, significantly sensitized cells to radiotherapy and temozolomide (U87: P < 0.01 and < 0.05, respectively; T98: P < 0.01 and < 0.01, respectively). Silencing of the LC3A gene sensitized mouse xenografts to radiation.
Conclusions: Autophagy in cancer cells may be a key factor of radio-resistance and chemo-resistance in glioblastoma cells. Blocking autophagy may improve the efficacy of radiochemotherapy for glioblastoma patients.
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Affiliation(s)
| | | | - Alexandra Giatromanolaki
- Department of Pathology, Democritus University of Thrace, and University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
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Koukourakis M, Tsolou A, Pouliliou S, Lamprou I, Papadopoulou M, Ilemosoglou M, Kostoglou G, Ananiadou D, Sivridis E, Giatromanolaki A. Blocking LDHA glycolytic pathway sensitizes glioblastoma cells to radiation and temozolomide. Biochem Biophys Res Commun 2017; 491:932-938. [PMID: 28756228 DOI: 10.1016/j.bbrc.2017.07.138] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 07/25/2017] [Indexed: 01/11/2023]
Abstract
PURPOSE Up-regulation of lactate dehydrogenase LDHA, is a frequent event in human malignancies and relate to poor postoperative outcome. In the current study we examined the hypothesis that LDHA and anaerobic glycolysis, may contribute to the resistance of glioblastoma to radiotherapy and to temozolomide. METHODS AND MATERIALS The expression of LDH5 isoenzyme (fully encoded by the LDHA gene) was assessed in human glioblastoma tissues. Experimental in vitro studies involved the T98 and U87 glioblastoma cell lines. Their sensitivity to radiotherapy and to temozolomide, following silencing of LDHA gene or following exposure to the LDHA chemical inhibitor 'oxamate' and to the glycolysis inhibitor '2-deoxy-d-glucose' (2DG), was studied. RESULTS Glioblastoma tissues showed strong cytoplasmic and nuclear LDH5 expression in 0-90% (median 20%) of the neoplastic cells. T98 and U87 cell lines showed that blocking glycolysis, either with LDHA gene silencing or exposure to oxamate (30 mM) and blockage of glycolysis with 2DG (500 μM), results in enhanced radiation sensitivity, an effect that was more robust in the T98 radioresistant cell line. Furthermore, all three glycolysis targeting methods, significantly sensitized both cell lines to Temozolomide. CONCLUSIONS The current study provides evidence that a large subgroup of human glioblastomas are highly glycolytic, and that inhibitors of glycolysis, like LDHA targeting agents, may prove of therapeutic importance by enhancing the efficacy of radiotherapy and temozolomide against this lethal disease.
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Affiliation(s)
- Michael Koukourakis
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece.
| | - Avgi Tsolou
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - Stamatia Pouliliou
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - Ioannis Lamprou
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - Maria Papadopoulou
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - Maria Ilemosoglou
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - Georgia Kostoglou
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - Dimitra Ananiadou
- Department of Radiotherapy / Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - Efthimios Sivridis
- Department of Pathology, Democritus University of Thrace, Alexandroupolis 68100, Greece
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Karagounis IV, Skourti EK, Liousia MV, Koukourakis MI. Assessment of Radiobiological α/β Ratio in Lung Cancer and Fibroblast Cell Lines Using Viability Assays. ACTA ACUST UNITED AC 2017; 31:175-179. [PMID: 28358697 DOI: 10.21873/invivo.11042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 01/30/2017] [Accepted: 02/01/2017] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM Altered fractionation is an area of intense clinical research in radiation oncology. Estimation of the α/β ratio of individual carcinomas after establishment of primary cell cultures from tumor biopsies may prove of importance in the individualization of radiotherapy schemes. MATERIALS AND METHODS Here we proposed a simple method to estimate the α/β ratio in cultured cell lines (two lung carcinomas: A549 and H1299; one lung fibroblast cell line: MRC5), using viability assays. RESULTS For the A549 cell line, the α/β ratio ranged from 14-25 Gy, for H1299 from 11-43 Gy and for the MRC5 fibroblast cell line this was far lower, ranging from 0.69 to 6 Gy. The α/β ratio decreased when extracted from comparisons of lower dose per fraction schemes. CONCLUSION The α/β ratio of a cell line can be easily defined after simple viability/dose fractionation experiments.
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Affiliation(s)
- Ilias V Karagounis
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Eleni K Skourti
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Maria V Liousia
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Michael I Koukourakis
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis, Greece
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Karagounis IV, Kalamida D, Mitrakas A, Pouliliou S, Liousia MV, Giatromanolaki A, Koukourakis MI. Repression of the autophagic response sensitises lung cancer cells to radiation and chemotherapy. Br J Cancer 2016; 115:312-21. [PMID: 27380135 DOI: 10.1038/bjc.2016.202] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 05/29/2016] [Accepted: 06/02/2016] [Indexed: 12/25/2022] Open
Abstract
Background: The cellular autophagic response to radiation is complex. Various cells and tissues respond differentially to radiation, depending on both the dose of exposure and the time post irradiation. In the current study, we determined the autophagosomal and lysosomal response to radiation in lung cancer cell lines by evaluating the expression of the associated proteins, as well as the effect of relevant gene silencing in radio and chemosensitisation. Furthermore, tumour sensitisation was evaluated in in vivo autophagic gene silencing model after irradiation. Methods: A549 and H1299 cell lines were utilised as in vitro cancer models. Both cell lines were transfected with various small-interfering RNAs, silencing auto-lysosomal genes, and irradiated with 4 Gy. Cell growth response was evaluated with AlamarBlue assay. Western blot and confocal microscopy were utilised for the characterisation of the auto-lysosomal flux. Also, the H1299 cell line was stable transfected with small-hairpin RNA of the MAP1LC3A gene, and the tumour radiosensitisation in Athymic Nude-Foxn1nu was evaluated. Results: Following exposure to 4 Gy of radiation, A549 cells exhibited a significant induction of the autophagic flux, which was not supported by transcriptional activation of auto-lysosomal genes (LC3A, LC3B, p62, TFEB and LAMP2a), resulting in aggresome accumulation. Recovery of transcriptional activity and autophagy efficacy occurred 7 days post irradiation. Alternatively, H1299 cells, a relatively radio-resistant cell line, sharply responded with an early (at 2 days) transcriptional activation of auto-lysosomal genes that sustained an effective autophagosomal flux, resulting in adequate aggresome clearance. Subsequently, we tested the silencing of four genes (LC3A, LC3B, TFEB and LAMP2a), confirming a significant radiosensitisation and chemosensitisation to various chemotherapeutic agents, including cisplatin and taxanes. In mouse xenografts, exposure to radiation significantly reduced tumour growth (P<0.001), which was exacerbated among shLC3A-H1299 transfected tumours. Conclusions: The ability of lung cancer cells to survive after irradiation at 4 Gy depends on their ability to sustain a functional autophagic flux. Abrogation of such ability results in increased radiosensitivity and susceptibility to various chemotherapy agents. Selective inhibitors of cancer cell autophagic function may prove important for the eradication of lung cancer.
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Koukourakis MI, Kakouratos C, Kalamida D, Bampali Z, Mavropoulou S, Sivridis E, Giatromanolaki A. Hypoxia-inducible proteins HIF1α and lactate dehydrogenase LDH5, key markers of anaerobic metabolism, relate with stem cell markers and poor post-radiotherapy outcome in bladder cancer. Int J Radiat Biol 2016; 92:353-63. [PMID: 27010533 DOI: 10.3109/09553002.2016.1162921] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE To assess whether anaerobic metabolism, proliferation activity and stem cell content are linked with radioresistance in bladder cancer. MATERIALS AND METHODS Tissue sections from 66 patients with invasive transitional cell bladder cancer treated with hypofractionated accelerated radiotherapy, was immunohistochemically analyzed for the Hypoxia-Inducible Factor 1α (HIF1α) and the anaerobic glycolysis enzyme lactate dehydrogenase 5 (LDH5). Proliferation index (Ki-67) and stem-cell marker (cluster of differentiation CD44, aldehyde dehydrogenase ALDH1) expression was also examined. RESULTS Both HIF1α and LDH5 expression were linked with high CD44 stem cell population (p = 0.001 and 0.05, respectively), while high Ki-67 proliferation index was linked with nuclear LDH5 expression (p = 0.03) and high histological grade (p = 0.02). A strong significant association of HIF1α (p = 0.0009) and of LDH5 (p < 0.0001) with poor local relapse free survival (LRFS) was noted, which was also confirmed in multivariate analysis. A significant association with overall survival was also noted. Silencing of lactate dehydrogenase LDHA gene in the human RT112 bladder cancer cell line, or exposure to oxamate (LDH activity inhibitor), resulted in strong radio-sensitization. CONCLUSIONS HIF1α and LDH5 are markers of poor outcome in patients with bladder cancer treated with radiotherapy. Blockage of anaerobic metabolism may prove of importance in clinical radiotherapy.
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Affiliation(s)
- Michael I Koukourakis
- a Department of Radiotherapy/Oncology , Democritus University of Thrace, and University General Hospital of Alexandroupolis , Alexandroupolis , Greece
| | - Christos Kakouratos
- a Department of Radiotherapy/Oncology , Democritus University of Thrace, and University General Hospital of Alexandroupolis , Alexandroupolis , Greece
| | - Dimitra Kalamida
- a Department of Radiotherapy/Oncology , Democritus University of Thrace, and University General Hospital of Alexandroupolis , Alexandroupolis , Greece
| | - Zoi Bampali
- a Department of Radiotherapy/Oncology , Democritus University of Thrace, and University General Hospital of Alexandroupolis , Alexandroupolis , Greece
| | | | - Efthimios Sivridis
- b Department of Pathology , Democritus University of Thrace, and University General Hospital of Alexandroupolis , Alexandroupolis , Greece
| | - Alexandra Giatromanolaki
- b Department of Pathology , Democritus University of Thrace, and University General Hospital of Alexandroupolis , Alexandroupolis , Greece
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Kalamida D, Karagounis IV, Giatromanolaki A, Koukourakis MI. Important role of autophagy in endothelial cell response to ionizing radiation. PLoS One 2014; 9:e102408. [PMID: 25010689 PMCID: PMC4092133 DOI: 10.1371/journal.pone.0102408] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 06/18/2014] [Indexed: 01/12/2023] Open
Abstract
Objectives Vasculature damage is an important contributor to the side-effects of radiotherapy. The aim of this study is to provide insights into the radiobiology of the autophagic response of endothelial cells. Methods and Materials Human umbilical vascular endothelial cells (HUVEC) were exposed to 2 Gy of ionizing radiation (IR) and studied using confocal microscopy and western blot analysis, at 4 and 8 days post-irradiation. The role of autophagy flux in HUVEC radio-sensitivity was also examined. Results IR-induced accumulation of LC3A+, LC3B+ and p62 cytoplasmic vacuoles, while in double immunostaining with lysosomal markers (LAMP2a and CathepsinD) repression of the autophagolysosomal flux was evident. Autophagy-related proteins (ATF4, HIF1α., HIF2α, Beclin1) were, however, induced excluding an eventual repressive effect of radiation on autophagy initiating protein expression. Exposure of HUVEC to SMER28, an mTOR-independent inducer of autophagy, enhanced proLC3 and LC3A, B-I protein expression and accelerated the autophagic flux. Pre-treatment of HUVEC with SMER28 protected against the blockage of autophagic flux induced by IR and conferred radio-resistance. Suppression of LC3A/LC3B proteins with siRNAs resulted in radio-sensitization. Conclusions The current data provide a rationale for the development of novel radioprotection policies targeting the autophagic pathway.
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Affiliation(s)
- Dimitra Kalamida
- Department of Radiotherapy/Oncology, Democritus University of Thrace, and University General Hospital of Alexandroupolis, Alexandroupolis, Greece
| | - Ilias V. Karagounis
- Department of Radiotherapy/Oncology, Democritus University of Thrace, and University General Hospital of Alexandroupolis, Alexandroupolis, Greece
| | - Alexandra Giatromanolaki
- Department of Pathology, Democritus University of Thrace, and University General Hospital of Alexandroupolis, Alexandroupolis, Greece
| | - Michael I. Koukourakis
- Department of Radiotherapy/Oncology, Democritus University of Thrace, and University General Hospital of Alexandroupolis, Alexandroupolis, Greece
- * E-mail:
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Koukourakis MI, Giatromanolaki A, Panteliadou M, Pouliliou SE, Chondrou PS, Mavropoulou S, Sivridis E. Lactate dehydrogenase 5 isoenzyme overexpression defines resistance of prostate cancer to radiotherapy. Br J Cancer 2014; 110:2217-23. [PMID: 24714743 PMCID: PMC4007238 DOI: 10.1038/bjc.2014.158] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 02/28/2014] [Accepted: 03/03/2014] [Indexed: 12/17/2022] Open
Abstract
Background: Radiotherapy provides high-cure rates in prostate cancer. Despite its overall slow clinical growth, high proliferation rates documented in a subset of tumours relate to poor radiotherapy outcome. This study examines the role of anaerobic metabolism in prostate cancer growth and resistance to radiotherapy. Methods: Biopsy samples from 83 patients with prostate cancer undergoing radical hypofractionated and accelerated radiotherapy were analysed for MIB1 proliferation index and for lactate dehydrogenase isoenzyme LDH5, a marker of tumour anaerobic metabolism. Ninety-five surgical samples were in parallel analysed. Correlation with histopathological variables, PSA and radiotherapy outcome was assessed. Dose–response experiments were performed in PC3 and DU145 cancer cell lines. Results: High MIB1 index (noted in 25% of cases) was directly related to Gleason score (P<0.0001), T3-stage (P=0.0008) and PSA levels (P=0.03). High LDH5 (noted in 65% of cases) was directly related to MIB1 index (P<0.0001), Gleason score (P=0.02) and T3-stage (P=0.001). High Gleason score, MIB1, LDH5 and PSA levels were significantly related to poor BRFS (P=0.007, 0.01, 0.03 and 0.01, respectively). High Gleason score (P=0.04), LDH5 (P=0.01) and PSA levels (P=0.003) were significantly related to local recurrence. MIB1 and T-stage did not affect local control. Silencing of LDHA gene in both prostate cancer cell lines resulted in significant radiosensitisation. Conclusions: LDH5 overexpression is significantly linked to highly proliferating prostate carcinomas and with biochemical failure and local relapse following radiotherapy. Hypoxia and LDHA targeting agents may prove useful to overcome radioresistance in a subgroup of prostate carcinomas with anaerobic metabolic predilection.
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Affiliation(s)
- M I Koukourakis
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - A Giatromanolaki
- Department of Pathology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - M Panteliadou
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - S E Pouliliou
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - P S Chondrou
- Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - S Mavropoulou
- Department of Pathology, Democritus University of Thrace, Alexandroupolis 68100, Greece
| | - E Sivridis
- Department of Pathology, Democritus University of Thrace, Alexandroupolis 68100, Greece
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Zachari MA, Chondrou PS, Pouliliou SE, Mitrakas AG, Abatzoglou I, Zois CE, Koukourakis MI. Evaluation of the alamarblue assay for adherent cell irradiation experiments. Dose Response 2013; 12:246-58. [PMID: 24910583 DOI: 10.2203/dose-response.13-024.koukourakis] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The AlamarBlue assay is based on fluorometric detection of metabolic mitochondrial activity of cells. In this study, we determined the methodology for application of the assay to radiation response experiments in 96-well plates. AlamarBlue was added and its reduction measured 7 hours later. Selection of the initial number of plated cells was important so that the number of proliferating cells remains lower than the critical number that produced full AlamarBlue reduction (plateau phase) at the time points of measurements. Culture medium was replaced twice a week to avoid suppression of viability due to nutrient competition and metabolic waste accumulation. There was no need to replace culture medium before adding AlamarBlue. Cell proliferation continued after irradiation and the suppression effect on cell viability was most evident on day 8. At this time point, by comparing measurements from irradiated vs. non-irradiated cells, for various dose levels, a viability dose response curve was plotted. Immediately after the 8(th) day (nadir), cells started to re-grow at a rate inversely related to the radiation dose. By comparing measurements at the time point of nadir vs. a convenient subsequent time point, re-growth dose response abilities were plotted, simulating clonogenic assays.
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Affiliation(s)
- Maria A Zachari
- Department of Radiotherapy / Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis, Greece
| | - Panagiota S Chondrou
- Department of Radiotherapy / Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis, Greece
| | - Stamatia E Pouliliou
- Department of Radiotherapy / Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis, Greece
| | - Achilleas G Mitrakas
- Department of Radiotherapy / Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis, Greece
| | - Ioannis Abatzoglou
- Department of Radiotherapy / Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis, Greece
| | - Christos E Zois
- Department of Radiotherapy / Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis, Greece
| | - Michael I Koukourakis
- Department of Radiotherapy / Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis, Greece
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