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Mercier AE, Prudent R, Pepper MS, De Koning L, Nolte E, Peronne L, Nel M, Lafanechère L, Joubert AM. Characterization of Signalling Pathways That Link Apoptosis and Autophagy to Cell Death Induced by Estrone Analogues Which Reversibly Depolymerize Microtubules. Molecules 2021; 26:molecules26030706. [PMID: 33572896 PMCID: PMC7866274 DOI: 10.3390/molecules26030706] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 01/07/2021] [Accepted: 01/12/2021] [Indexed: 11/16/2022] Open
Abstract
The search for novel anti-cancer compounds which can circumvent chemotherapeutic drug resistance and limit systemic toxicity remains a priority. 2-Ethyl-3-O-sulphamoyl-estra-1,3,5(10)15-tetraene-3-ol-17one (ESE-15-one) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) are sulphamoylated 2-methoxyestradiol (2-ME) analogues designed by our research team. Although their cytotoxicity has been demonstrated in vitro, the temporal and mechanistic responses of the initiated intracellular events are yet to be determined. In order to do so, assays investigating the compounds' effects on microtubules, cell cycle progression, signalling cascades, autophagy and apoptosis were conducted using HeLa cervical- and MDA-MB-231 metastatic breast cancer cells. Both compounds reversibly disrupted microtubule dynamics as an early event by binding to the microtubule colchicine site, which blocked progression through the cell cycle at the G1/S- and G2/M transitions. This was supported by increased pRB and p27Kip1 phosphorylation. Induction of apoptosis with time-dependent signalling involving the p-JNK, Erk1/2 and Akt/mTOR pathways and loss of mitochondrial membrane potential was demonstrated. Inhibition of autophagy attenuated the apoptotic response. In conclusion, the 2-ME analogues induced a time-dependent cross-talk between cell cycle checkpoints, apoptotic signalling and autophagic processes, with an increased reactive oxygen species formation and perturbated microtubule functioning appearing to connect the processes. Subtle differences in the responses were observed between the two compounds and the different cell lines.
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Affiliation(s)
- Anne E. Mercier
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (E.N.); (M.N.); (L.L.); (A.M.J.)
- Correspondence: ; Tel.: +27-(0)-12-319-2141
| | - Renaud Prudent
- Institute for Advanced Biosciences, Team Regulation and Pharmacology of the Cytoskeleton, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38700 Grenoble, France; (R.P.); (L.P.)
| | - Michael S. Pepper
- Institute for Cellular and Molecular Medicine, Department of Immunology, School of Medicine, SAMRC Extramural Unit for Stem Cell Research and Therapy, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa;
| | - Leanne De Koning
- RPPA Platform, Institut Curie Centre de Recherche, PSL Research University, Paris 75248, France;
| | - Elsie Nolte
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (E.N.); (M.N.); (L.L.); (A.M.J.)
| | - Lauralie Peronne
- Institute for Advanced Biosciences, Team Regulation and Pharmacology of the Cytoskeleton, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38700 Grenoble, France; (R.P.); (L.P.)
| | - Marcel Nel
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (E.N.); (M.N.); (L.L.); (A.M.J.)
| | - Laurence Lafanechère
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (E.N.); (M.N.); (L.L.); (A.M.J.)
- Institute for Advanced Biosciences, Team Regulation and Pharmacology of the Cytoskeleton, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38700 Grenoble, France; (R.P.); (L.P.)
| | - Anna M. Joubert
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (E.N.); (M.N.); (L.L.); (A.M.J.)
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Xianchu L, Ming L, Xiangbin L, Lan Z. Grape seed proanthocyanidin extract supplementation affects exhaustive exercise-induced fatigue in mice. Food Nutr Res 2018; 62:1421. [PMID: 29904333 PMCID: PMC5995222 DOI: 10.29219/fnr.v62.1421] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 05/01/2018] [Accepted: 05/03/2018] [Indexed: 12/22/2022] Open
Abstract
Background Grape seed proanthocyanidin extract (GSPE) has been extensively reported to possess a wide range of beneficial properties in multiple tissue damage. Previous studies have shown that exhaustive exercise-induced fatigue associates with oxidative stress injury, inflammatory response, and mitochondrial dysfunction. Objective The aim of this study is to investigate the anti-fatigue effects of GSPE in mice and explore its possible underlying mechanism. Design The mouse model of exhaustive exercise-induced fatigue was established by using the forced swimming test, and GSPE was orally treated for successive 28 days at 0, 1, 50 and 100 mg/kg/day of body weight, designated the control, GSPE-L, GSPE-M and GSPE-H groups, respectively. Results The presented results showed that treatment of GSPE at a dose of 50 and 100 mg/kg/day of body weight significantly relieved exhaustive exercise-induced fatigue, indicated by increasing the forced swimming time. In addition, treatment of GSPE significantly improved the creatine phosphokinase and lactic dehydrogenase, as well as lactic acid level in exhaustive swimming. For underlying mechanisms, treatment of GSPE had anti-fatigue effects by promoting antioxidant ability and resisting oxidative effect, as represented by increased total antioxidative capability levels, enhanced superoxide dismutase and catalase activities, and ameliorated malondialdehyde levels. Furthermore, treatment of GSPE significantly inhibited the activity of tumor necrosis factor-α and interleukin-1β, which suggested that its protective effects on exhaustive exercise-induced fatigue may be attributed to inhibition of inflammatory response. Last but not the least, treatment of GSPE significantly improved succinate dehydrogenase and Na+-K+-ATPase levels to enhance mitochondrial function during exhaustive swimming-induced fatigue. Conclusions These results proved that treatment of GSPE possessed the beneficial properties of anti-inflammatory, antioxidant, and mitochondrial protection to improve exhaustive exercise, which suggested that GSPE could be used as an effective functional food to delay fatigue.
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Affiliation(s)
- Liu Xianchu
- Institute of Physical Education, Hunan University of Arts and Science, Hunan Province, Changde, China.,Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Liu Ming
- Institute of Physical Education, Hunan University of Arts and Science, Hunan Province, Changde, China.,Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Liu Xiangbin
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Zheng Lan
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
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Nkandeu SD, van den Bout I, Cronjé MJ, van Papendorp DH, Joubert AM. A Novel 2-Methoxyestradiol Analogue Is Responsible for Vesicle Disruption and Lysosome Aggregation in Breast Cancer Cells. Pharmacology 2018; 102:9-16. [PMID: 29672318 DOI: 10.1159/000487443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 01/30/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND 2-Methoxyestradiol (2ME2) is an endogenous metabolite of 17-β-estradiol with anti-proliferative and anti-angiogenic properties. Due to 2ME2's rapid metabolism and low oral bioavailability in in vivo settings, 2ME2 analogues have been designed to alleviate these issues. One of these compounds is 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16). A previous work alluded to the ability of ESE-16 to induce autophagic cell death. Therefore, we investigated the mode of action of ESE-16 by studying its effects on autophagy, vesicle formation, and lysosomal organisation. SUMMARY Vesicle formation and autophagy induction were analysed by transmission electron microscopy (TEM), monodansylcadaverine (MDC) staining and Lysotracker staining, while autophagosome turnover was analysed using microtubule-associated protein 1A/1B-light chain 3 (LC3 lipidation) analysis. MDC staining of acidic vesicles revealed an increase both in the number and size of vesicles after ESE-16 exposure. This was confirmed by TEM. Lysotracker staining indicated an increase in the size of lysosomes, as well as changes in their distribution within the cell. However, autophagy was not induced, since LC3 lipidation did not increase after exposure to ESE-16. Key -Messages: This study showed that ESE-16 exposure leads to the aggregation of acidic vesicles, identified as lysosomes, not accompanied by an induction of autophagy. Therefore, ESE-16 disrupts normal endocytic vesicle maturation likely through the inhibition of the microtubule function.
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Affiliation(s)
- Sandra D Nkandeu
- Department of Physiology, University of Pretoria, Pretoria, South Africa
| | - Iman van den Bout
- Department of Physiology, University of Pretoria, Pretoria, South Africa.,Centre for Neuroendocrinology, University of Pretoria, Pretoria, South Africa
| | - Marianne J Cronjé
- Department of Biochemistry, University of Johannesburg, Johannesburg, South Africa
| | | | - Anna M Joubert
- Department of Physiology, University of Pretoria, Pretoria, South Africa
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The in vitro effects of a novel estradiol analog on cell proliferation and morphology in human epithelial cervical carcinoma. Cell Mol Biol Lett 2018; 23:10. [PMID: 29568313 PMCID: PMC5859677 DOI: 10.1186/s11658-018-0079-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 03/12/2018] [Indexed: 01/04/2023] Open
Abstract
Background The majority of novel chemotherapeutics target the cell cycle, aiming to effect arrest and cause apoptosis. One such agent, 2-methoxyestradiol (2ME), has been shown to possess anticancer properties against numerous cancer types, both in vitro and in vivo. Despite its promise, 2ME has exhibited limitations, including low oral bioavailability and rapid hepatic enzymatic inactivation in vivo. A novel sulphamoylated estrogen analog, 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16), was in silico-designed in our laboratory to overcome these issues. It was then synthesized by a pharmaceutical company and used in an in vitro antiproliferative effect study on a human cervical carcinoma (HeLa) cell line. Results Cell proliferation data obtained from the crystal violet assay and real-time cell analysis demonstrated that 0.2 μM of ESE-16 had a significant inhibitory effect on the HeLa cells 24 h post-exposure. Immunofluorescence showed that ESE-16 is a microtubule disruptor that causes cells to undergo a mitotic block. Qualitative morphological studies using polarization-optical transmitted light differential interference contrast (PlasDIC) and light microscopy revealed a decrease in cell density and an increase in the number of cells arrested in metaphase. After ESE-16 exposure, hallmarks of apoptosis were also observed, including membrane blebbing, chromatin condensation and the presence of apoptotic bodies. Flow cytometry provided quantitative results from cell cycle progression analysis, indicating cells undergoing apoptosis and cells in the G2/M phase of the cell cycle, confirming cell cycle arrest in metaphase after ESE-16 treatment. Quantification of the ESE-16-mediated upregulation of cyclin B in HeLa cells and spectrophotometric and flow cytometric confirmation of cell death via apoptosis further confirmed the substance's impact. Conclusion ESE-16 exerts its antiproliferative effects through microtubule disruption, which induces a mitotic block culminating in apoptosis. This research provided information on ESE-16 as a potential antitumor agent and on cellular targets that could aid in the design of prospective microtubule-disrupting compounds. Further in vitro and in vivo investigations of this novel compound are needed.
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Lin SR, Fu YS, Tsai MJ, Cheng H, Weng CF. Natural Compounds from Herbs that can Potentially Execute as Autophagy Inducers for Cancer Therapy. Int J Mol Sci 2017; 18:ijms18071412. [PMID: 28671583 PMCID: PMC5535904 DOI: 10.3390/ijms18071412] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 06/19/2017] [Accepted: 06/27/2017] [Indexed: 01/07/2023] Open
Abstract
Accumulated evidence indicates that autophagy is a response of cancer cells to various anti-cancer therapies. Autophagy is designated as programmed cell death type II, and is characterized by the formation of autophagic vacuoles in the cytoplasm. Numerous herbs, including Chinese herbs, have been applied to cancer treatments as complementary and alternative medicines, supplements, or nutraceuticals to dampen the side or adverse effects of chemotherapy drugs. Moreover, the tumor suppressive actions of herbs and natural products induced autophagy that may lead to cell senescence, increase apoptosis-independent cell death or complement apoptotic processes. Hereby, the underlying mechanisms of natural autophagy inducers are cautiously reviewed in this article. Additionally, three natural compounds—curcumin, 16-hydroxycleroda-3,13-dien-15,16-olide, and prodigiosin—are presented as candidates for autophagy inducers that can trigger cell death in a supplement or alternative medicine for cancer therapy. Despite recent advancements in therapeutic drugs or agents of natural products in several cancers, it warrants further investigation in preclinical and clinical studies.
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Affiliation(s)
- Shian-Ren Lin
- Department of Life Science and Institute of Biotechnology, National Dong Hwa University, 97401 Hualien, Taiwan.
| | - Yaw-Syan Fu
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, 807 Kaohsiung city, Taiwan.
| | - May-Jywan Tsai
- Neural Regeneration Laboratory, Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, 11221 Taipei, Taiwan.
- Center for Neural Regeneration, Neurological Institute, Taipei Veterans General Hospital, 11221 Taipei, Taiwan.
| | - Henrich Cheng
- Neural Regeneration Laboratory, Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, 11221 Taipei, Taiwan.
- Center for Neural Regeneration, Neurological Institute, Taipei Veterans General Hospital, 11221 Taipei, Taiwan.
| | - Ching-Feng Weng
- Department of Life Science and Institute of Biotechnology, National Dong Hwa University, 97401 Hualien, Taiwan.
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Ex vivo apoptotic and autophagic influence of an estradiol analogue on platelets. Exp Hematol Oncol 2016; 5:18. [PMID: 27429862 PMCID: PMC4946154 DOI: 10.1186/s40164-016-0048-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 07/06/2016] [Indexed: 01/06/2023] Open
Abstract
Background Platelets are known contributors to the vascularization, metastasis and growth of tumors. Upon their interaction with cancer cells they are activated resulting in degranulation and release of constituents. Since the apoptotic- and autophagic effects of 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) has been shown to occur in vitro and this compound was designed to bind to carbonic anhydrase II (CAII), the possible occurrence of these cell death mechanisms in platelets as circulatory components, is of importance. Methods Scanning electron microscopy was used to assess morphological changes in platelets after exposure to ESE-16. The possible apoptotic- and autophagic effect of ESE-16 in platelets was also determined by means of flow cytometry through measurement of Annexin V-FITC, caspase 3 activity, autophagy related protein 5 levels and light chain 3-I to light chain 3-II conversion. Results Scanning electron microscopy revealed no changes in ESE-16-treated platelets when compared to vehicle-treated samples. Apoptosis detection by Annexin V-FITC and measurement of caspase 3 activity indicated that there was no increase in apoptosis when platelets were exposed to ESE-16. The incidence of autophagy by measurement of autophagy related protein 5 levels and light chain 3-I to light chain 3-II conversion showed that exposure to ESE-16 did not cause the incidence of autophagy in platelets. Conclusion This is the first ex vivo study reporting on involvement of apoptosis- and autophagy-related targets in platelets after exposure to ESE-16, warranting further investigation in platelets of cancer patients.
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van Vuuren RJ, Visagie MH, Theron AE, Joubert AM. Antimitotic drugs in the treatment of cancer. Cancer Chemother Pharmacol 2015; 76:1101-12. [PMID: 26563258 PMCID: PMC4648954 DOI: 10.1007/s00280-015-2903-8] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/03/2015] [Indexed: 01/05/2023]
Abstract
Cancer is a complex disease since it is adaptive in such a way that it can promote proliferation and invasion by means of an overactive cell cycle and in turn cellular division which is targeted by antimitotic drugs that are highly validated chemotherapy agents. However, antimitotic drug cytotoxicity to non-tumorigenic cells and multiple cancer resistance developed in response to drugs such as taxanes and vinca alkaloids are obstacles faced in both the clinical and basic research field to date. In this review, the classes of antimitotic compounds, their mechanisms of action and cancer cell resistance to chemotherapy and other limitations of current antimitotic compounds are highlighted, as well as the potential of novel 17-β estradiol analogs as cancer treatment.
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Affiliation(s)
| | - Michelle H Visagie
- Department of Physiology, University of Pretoria, Private Bag x 323, Arcadia, 0007, South Africa.
| | - Anne E Theron
- Department of Physiology, University of Pretoria, Private Bag x 323, Arcadia, 0007, South Africa
| | - Annie M Joubert
- Department of Physiology, University of Pretoria, Private Bag x 323, Arcadia, 0007, South Africa
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Elaborating the role of natural products-induced autophagy in cancer treatment: achievements and artifacts in the state of the art. BIOMED RESEARCH INTERNATIONAL 2015; 2015:934207. [PMID: 25821829 PMCID: PMC4363717 DOI: 10.1155/2015/934207] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 09/29/2014] [Accepted: 10/02/2014] [Indexed: 12/12/2022]
Abstract
Autophagy is a homeostatic process that is highly conserved across different types of mammalian cells. Autophagy is able to relieve tumor cell from nutrient and oxidative stress during the rapid expansion of cancer. Excessive and sustained autophagy may lead to cell death and tumor shrinkage. It was shown in literature that many anticancer natural compounds and extracts could initiate autophagy in tumor cells. As summarized in this review, the tumor suppressive action of natural products-induced autophagy may lead to cell senescence, provoke apoptosis-independent cell death, and complement apoptotic cell death by robust or target-specific mechanisms. In some cases, natural products-induced autophagy could protect tumor cells from apoptotic death. Technical variations in detecting autophagy affect data quality, and study focus should be made on elaborating the role of autophagy in deciding cell fate. In vivo study monitoring of autophagy in cancer treatment is expected to be the future direction. The clinical-relevant action of autophagy-inducing natural products should be highlighted in future study. As natural products are an important resource in discovery of lead compound of anticancer drug, study on the role of autophagy in tumor suppressive effect of natural products continues to be necessary and emerging.
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Xie T, Li SJ, Guo MR, Wu Y, Wang HY, Zhang K, Zhang X, Ouyang L, Liu J. Untangling knots between autophagic targets and candidate drugs, in cancer therapy. Cell Prolif 2015; 48:119-39. [PMID: 25650136 DOI: 10.1111/cpr.12167] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 10/05/2014] [Indexed: 02/05/2023] Open
Abstract
Autophagy is an evolutionarily conserved lysosomal mechanism implicated in a wide variety of pathological processes, such as cancer. Autophagy can be regulated by a limited number of autophagy-related genes (Atgs) such as oncogenic Bcl-2/Bcl-XL , mTORC1, Akt and PI3KCI, and tumour suppressive proteins PI3KCIII, Beclin-1, Bif-1, p53, DAPKs, PTEN and UVRAG, which play their crucial roles in regulating autophagy-related cancer. As autophagy has a dual role in cancer cells, with tumour-promoting and tumour-suppressing properties, it has become an attractive target for a series of emerging small molecule drugs. In this review, we reveal new discoveries of related small molecules or chemical compounds that can regulate autophagic pathways and lead to pro-death or pro-survival autophagy, in different types of cancer. We discuss the knots between autophagic targets and candidate drugs, in the hope of shedding new light on exploiting new anti-tumour small molecule drugs for future cancer therapy.
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Affiliation(s)
- Tao Xie
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
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Repsold L, Mqoco T, Wolmarans E, Nkandeu S, Theron J, Piorkowski T, Toit PD, Papendorp DV, Joubert AM. Ultrastructural changes of erythrocytes in whole blood after exposure to prospective in silico-designed anticancer agents: a qualitative case study. Biol Res 2014; 47:39. [PMID: 25299962 PMCID: PMC4167501 DOI: 10.1186/0717-6287-47-39] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 08/20/2014] [Indexed: 12/25/2022] Open
Abstract
Background Novel, in silico-designed anticancer compounds were synthesized in our laboratory namely, 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16). These compounds were designed to have improved bioavailability when compared to their source compound, 2-methoxyestradiol. This theoretically would be due to their increased binding affinity to carbonic anhydrase II, present in erythrocytes. Since the novel compounds under investigation are proposed to be transported within erythrocytes bound to carbonic anhydrase II, the morphological effect which they may exert on whole blood and erythrocytes is of great significance. A secondary outcome included revision of previously reported procedures for the handling of the whole blood sample. The purpose of this study was twofold. Firstly, the ultrastructural morphology of a healthy female’s erythrocytes was examined via scanning electron microscopy (SEM) after exposure to the newly in silico-designed compounds. Morphology of erythrocytes following exposure to ESE-15-ol and ESE-16 for 3 minutes and 24 hours at 22°C were described with the use of SEM. The haemolytic activity of the compounds after 24 hours exposure were also determined with the ex vivo haemolysis assay. Secondly, storage conditions of the whole blood sample were investigated by determining morphological changes after a 24 hour storage period at 22°C and 37°C. Results No significant morphological changes were observed in the erythrocyte morphology after exposure to the novel anticancer compounds. Storage of the whole blood samples at 37°C for 24 hours resulted in visible morphological stress in the erythrocytes. Erythrocytes incubated at 22°C for 24 hours showed no structural deformity or distress. Conclusions From this research the optimal temperature for ex vivo exposure of whole blood samples to ESE-15-ol and ESE-16 for 24 hours was determined to be 22°C. Data from this study revealed the potential of these compounds to be applied to ex vivo study techniques, since no damage occurred to erythrocytes ultrastructure under these conditions. As no structural changes were observed in erythrocytes exposed to ESE-15-ol and ESE-16, further ex vivo experiments will be conducted into the potential effects of these compounds on whole blood. Optimal incubation conditions up to 24 hours for whole blood were established as a secondary outcome.
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Affiliation(s)
- Lisa Repsold
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Thandi Mqoco
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Elize Wolmarans
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Sandra Nkandeu
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Joji Theron
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Tomek Piorkowski
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Peet du Toit
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Dirk van Papendorp
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Annie Margaretha Joubert
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
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Repsold L, Pretorius E, Joubert AM. An estrogen analogue and promising anticancer agent refrains from inducing morphological damage and reactive oxygen species generation in erythrocytes, fibrin and platelets: a pilot study. Cancer Cell Int 2014; 14:48. [PMID: 24932135 PMCID: PMC4057810 DOI: 10.1186/1475-2867-14-48] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/26/2014] [Indexed: 12/22/2022] Open
Abstract
Background 2-Methoxyestradiol is known to have antitumour and antiproliferative action in vitro and in vivo. However, when 2-methoxyestradiol is orally administered, it is rapidly oxidized by the enzyme 17β-hydroxysteriod dehydrogenase in the gastrointestinal tract. Therefore, 2-methoxyestradiol never reaches high enough concentrations in the tissue to be able to exert these antitumour properties. This resulted in the in silico-design of 2-methoxyestradiol analogues in collaboration with the Bioinformatics and Computational Biology Unit (UP) and subsequent synthesis by iThemba Pharmaceuticals (Pty) Ltd (Modderfontein, Midrand, South Africa). One such a novelty-designed analogue is 2-ethyl-3-O-sulphamoyl-estra-1, 3, 5(10)16-tetraene (ESE-16). Methods This pilot study aimed to determine the morphological effect and possible generation of reactive oxygen species by ESE-16 on erythrocytes and platelet samples (with and without added thrombin) by means of scanning electron microscopy, transmission electron microscopy and flow cytometry. Results Erythrocytes and platelets were exposed to ESE-16 at a concentration of 180nM for 24 hours. Scanning- and transmission electron microscopy indicated that ESE-16 did not cause changes to erythrocytes, platelets or fibrin networks. Flow cytometry measurements of hydrogen peroxide and superoxide indicated that ESE-16 does not cause an increase in the generation of reactive oxygen species in these blood samples. Conclusion Further in vivo research is warranted to determine whether this novel in silico-designed analogue may impact on development of future chemotherapeutic agents and whether it could be considered as an antitumour agent.
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Affiliation(s)
- Lisa Repsold
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Etheresia Pretorius
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Annie Margaretha Joubert
- Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
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Wolmarans E, Sippel K, McKenna R, Joubert A. Induction of the intrinsic apoptotic pathway via a new antimitotic agent in an esophageal carcinoma cell line. Cell Biosci 2014; 4:68. [PMID: 25937890 PMCID: PMC4417530 DOI: 10.1186/2045-3701-4-68] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 11/02/2014] [Indexed: 11/29/2022] Open
Abstract
Background 2-Ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) is a unique, in silico-designed compound with possible anticancer properties, which were identified in our laboratory. This compound is capable of interfering with microtubule dynamics and is believed to have potential carbonic anhydrase IX inhibiting activity. In this study, it was investigated whether ESE-16 is capable of inducing apoptosis in vitro in the esophageal carcinoma SNO cell line via the intrinsic pathway at a concentration of 0.2 μM with an exposure time of 24 hours. Results Qualitative results were obtained via light microscopy, transmission electron microscopy and confocal microscopy. Results showed hallmarks of apoptosis in the ESE-16-treated cells. In addition, data revealed an increase in the number of ESE-16-treated cells blocked in metaphase. Cell death via apoptosis in the ESE-16-treated cells was confirmed by studying the internal ultrastructure of the cells via transmission electron microscopy, while confocal microscopy revealed abnormal spindle formation and condensed chromatin in ESE-16-treated cells, thus confirming metaphase block. Quantitative results were obtained via flow cytometry and spectrophotometry. Cell death via apoptosis in ESE-16-treated cells was quantitatively confirmed by the Annexin V-FITC apoptosis detection assay. Flow cytometry and spectrophotometry revealed dissipation of mitochondrial membrane potential and an increase in superoxide levels in the ESE-16-treated cells when compared to the relevant controls. Both initiator caspase 9 and effector caspase 3 activities were increased, which demonstrates that ESE-16 causes cell death in a caspase-dependent manner. Conclusions This was the first in vitro study conducted to investigate the action mechanism of ESE-16 on an esophageal carcinoma cell line. The results provided valuable information on the action mechanism of this potential anticancer agent. It can be concluded that the novel in silico-designed compound exerts an anti-proliferative effect on the esophageal carcinoma SNO cell line by disrupting microtubule function resulting in metaphase block. This culminates in apoptotic cell death via the intrinsic apoptotic pathway. This research provided cellular targets warranting in vivo assessment of ESE-16’s potential as an anticancer agent.
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Affiliation(s)
- Elize Wolmarans
- Department of Physiology, University of Pretoria, Pretoria, South Africa
| | - Katherine Sippel
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas USA
| | - Robert McKenna
- McKnight Institute, University of Florida, Gainesville, Florida USA
| | - Annie Joubert
- Department of Physiology, University of Pretoria, Pretoria, South Africa
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