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Tse HM, Gardner G, Dominguez-Bendala J, Fraker CA. The Importance of Proper Oxygenation in 3D Culture. Front Bioeng Biotechnol 2021; 9:634403. [PMID: 33859979 PMCID: PMC8042214 DOI: 10.3389/fbioe.2021.634403] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 03/09/2021] [Indexed: 12/15/2022] Open
Abstract
Cell culture typically employs inexpensive, disposable plasticware, and standard humidified CO2/room air incubators (5% CO2, ∼20% oxygen). These methods have historically proven adequate for the maintenance of viability, function, and proliferation of many cell types, but with broad variation in culture practices. With technological advances it is becoming increasingly clear that cell culture is not a “one size fits all” procedure. Recently, there is a shift toward comprehension of the individual physiological niches of cultured cells. As scale-up production of single cell and 3D aggregates for therapeutic applications has expanded, researchers have focused on understanding the role of many environmental metabolites/forces on cell function and viability. Oxygen, due to its role in cell processes and the requirement for adequate supply to maintain critical energy generation, is one such metabolite gaining increased focus. With the advent of improved sensing technologies and computational predictive modeling, it is becoming evident that parameters such as cell seeding density, culture media height, cellular oxygen consumption rate, and aggregate dimensions should be considered for experimental reproducibility. In this review, we will examine the role of oxygen in 3D cell culture with particular emphasis on primary islets of Langerhans and stem cell-derived insulin-producing SC-β cells, both known for their high metabolic demands. We will implement finite element modeling (FEM) to simulate historical and current culture methods in referenced manuscripts and innovations focusing on oxygen distribution. Our group and others have shown that oxygen plays a key role in proliferation, differentiation, and function of these 3D aggregates. Their culture in plastic consistently results in core regions of hypoxia/anoxia exacerbated by increased media height, aggregate dimensions, and oxygen consumption rates. Static gas permeable systems ameliorate this problem. The use of rotational culture and other dynamic culture systems also have advantages in terms of oxygen supply but come with the caveat that these endocrine aggregates are also exquisitely sensitive to mechanical perturbation. As recent work demonstrates, there is a strong rationale for the use of alternate in vitro systems to maintain physio-normal environments for cell growth and function for better phenotypic approximation of in vivo counterparts.
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Affiliation(s)
- Hubert M Tse
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Graeme Gardner
- Department of Surgery, Diabetes Research Institute, Leonard M. Miller School of Medicine, University of Miami, Coral Gables, FL, United States
| | - Juan Dominguez-Bendala
- Department of Surgery, Diabetes Research Institute, Leonard M. Miller School of Medicine, University of Miami, Coral Gables, FL, United States.,Department of Cell Biology and Anatomy, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Christopher A Fraker
- Department of Surgery, Diabetes Research Institute, Leonard M. Miller School of Medicine, University of Miami, Coral Gables, FL, United States
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Abstract
A three-dimensional (3D) tissue model has significant advantages over the conventional two-dimensional (2D) model. A 3D model mimics the relevant in-vivo physiological conditions, allowing a cell culture to serve as an effective tool for drug discovery, tissue engineering, and the investigation of disease pathology. The present reviews highlight the recent advances and the development of microfluidics based methods for the generation of cell spheroids. The paper emphasizes on the application of microfluidic technology for tissue engineering including the formation of multicellular spheroids (MCS). Further, the paper discusses the recent technical advances in the integration of microfluidic devices for MCS-based high-throughput drug screening. The review compares the various microfluidic techniques and finally provides a perspective for the future opportunities in this research area.
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Sinek JP, Sanga S, Zheng X, Frieboes HB, Ferrari M, Cristini V. Predicting drug pharmacokinetics and effect in vascularized tumors using computer simulation. J Math Biol 2008; 58:485-510. [PMID: 18781304 PMCID: PMC2782117 DOI: 10.1007/s00285-008-0214-y] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 01/30/2008] [Indexed: 10/26/2022]
Abstract
In this paper, we investigate the pharmacokinetics and effect of doxorubicin and cisplatin in vascularized tumors through two-dimensional simulations. We take into account especially vascular and morphological heterogeneity as well as cellular and lesion-level pharmacokinetic determinants like P-glycoprotein (Pgp) efflux and cell density. To do this we construct a multi-compartment PKPD model calibrated from published experimental data and simulate 2-h bolus administrations followed by 18-h drug washout. Our results show that lesion-scale drug and nutrient distribution may significantly impact therapeutic efficacy and should be considered as carefully as genetic determinants modulating, for example, the production of multidrug-resistance protein or topoisomerase II. We visualize and rigorously quantify distributions of nutrient, drug, and resulting cell inhibition. A main result is the existence of significant heterogeneity in all three, yielding poor inhibition in a large fraction of the lesion, and commensurately increased serum drug concentration necessary for an average 50% inhibition throughout the lesion (the IC(50) concentration). For doxorubicin the effect of hypoxia and hypoglycemia ("nutrient effect") is isolated and shown to further increase cell inhibition heterogeneity and double the IC(50), both undesirable. We also show how the therapeutic effectiveness of doxorubicin penetration therapy depends upon other determinants affecting drug distribution, such as cellular efflux and density, offering some insight into the conditions under which otherwise promising therapies may fail and, more importantly, when they will succeed. Cisplatin is used as a contrast to doxorubicin since both published experimental data and our simulations indicate its lesion distribution is more uniform than that of doxorubicin. Because of this some of the complexity in predicting its therapeutic efficacy is mitigated. Using this advantage, we show results suggesting that in vitro monolayer assays using this drug may more accurately predict in vivo performance than for drugs like doxorubicin. The nonlinear interaction among various determinants representing cell and lesion phenotype as well as therapeutic strategies is a unifying theme of our results. Throughout it can be appreciated that macroscopic environmental conditions, notably drug and nutrient distributions, give rise to considerable variation in lesion response, hence clinical resistance. Moreover, the synergy or antagonism of combined therapeutic strategies depends heavily upon this environment.
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Affiliation(s)
- John P Sinek
- Department of Mathematics, University of California, Irvine, CA, USA
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Dubessy C, Merlin JM, Marchal C, Guillemin F. Spheroids in radiobiology and photodynamic therapy. Crit Rev Oncol Hematol 2000; 36:179-92. [PMID: 11033305 DOI: 10.1016/s1040-8428(00)00085-8] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Spheroids are tridimensional aggregates of tumor cells coming from one or several cell clones. This model, which mimics the micro-tumors structure and some of their properties, shows oxygen, pH and nutrient gradients inducing a necrotic area in the center of the spheroid. Analysis of spheroids, cultured under static or stirred conditions, can be performed on whole spheroids or dissociated spheroids. The spheroids sensitivity to ionizing radiation and photodynamic therapy can be altered by oxygen status, damage repair, intercellular commmunications and apoptosis induction, as in experimental tumor models. In radiobiology, the similarity of radiation response between spheroids and tumor xenograft bearing mice makes the spheroids to be a good alternative model to in vivo irradiation studies. In photodynamic therapy, spheroids lead to a better understanding of the own tumor response without interactions with vascular system. Finally, despite the quality of spheroid model, only the use of new technology for analysis of spheroid populations will help to increase their experimental use, particularly in preclinical oncology.
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Affiliation(s)
- C Dubessy
- Laboratoire de Recherche en Oncologie, Centre Alexis Vautrin, 54511, cedex, Vandoeuvre-Nancy, France
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Kunz-Schughart LA, Groebe K, Mueller-Klieser W. Three-dimensional cell culture induces novel proliferative and metabolic alterations associated with oncogenic transformation. Int J Cancer 1996; 66:578-86. [PMID: 8635877 DOI: 10.1002/(sici)1097-0215(19960516)66:4<578::aid-ijc25>3.0.co;2-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
To date, cell biological characteristics of oncogene-transfected cells have been investigated either in relatively homogeneous monolayer cultures or in heterogeneous tumors in vivo. To evaluate the emergence of cellular heterogeneity during tumor formation, we have established a multicellular spheroid system from an oncogene-dependent, genetically determined 2-stage carcinogenesis model for 3-dimensional growth under well-defined conditions. The effect of T24Ha-ras transfection on cellular growth, proliferation, cell viability and oxygenation was investigated using spontaneously immortalized (Rat1) and c-myc-transfected (M1) Fisher 344 rat embryo fibroblasts and a tumorigenic T24Ha-ras-transfected clone of each (Rat1-T1 and MR1). Spheroid volume growth curves and [3H]thymidine autoradiographs clearly demonstrated that spheroids better reflect the degree of tumorigenicity in vivo as opposed to monolayer cultures. Studies on Rat1 and M1 aggregates showed that the potential for tumor formation of Rat1 cells might be manifested in vitro as an increased capability of the cells to survive in 3D culture. pO2 measurements confirmed that neither cell quiescence nor cell death in the pseudo-normal cell aggregate types is due to an oxygen deficiency. In contrast, depletion of oxygen coincided with necrotic cell death in Rat1-T1 spheroids and proliferation arrest in MR1 cultures. Cell-line-specific attributes in 3D culture that were not specifically related to ras transfection of the cells included histological structure, development of necrosis and thickness of viable cell rim. However, growth behavior, proliferation characteristics and their association with the oxygen supply might be correlated with the extent of transformation.
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Woods ML, Koch CJ, Lord EM. Detection of individual hypoxic cells in multicellular spheroids by flow cytometry using the 2-nitroimidazole, EF5, and monoclonal antibodies. Int J Radiat Oncol Biol Phys 1996; 34:93-101. [PMID: 12118570 DOI: 10.1016/0360-3016(95)02006-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
PURPOSE The purpose of this work was to evaluate EF5, a 2-nitroimidazole compound, and anti-EF5 antibodies as a method to quantify radiobiologically hypoxic cells. METHODS AND MATERIALS Multicellular spheroids of EMT6 mammary sarcoma cells were used as a model to identify hypoxic cells that were resistant to radiation damage. This was accomplished by incubating the spheroids with the 2-nitroimidazole (EF5), which forms hypoxia-dependent adducts with cellular macromolecules that are detected by fluorescent monoclonal antibodies. RESULTS Cells from spheroids grown for 2 days in sealed flasks had an increased surviving fraction following radiation as compared to fully reoxygenated spheroids, indicating the presence of radiobiological hypoxia. Treatment of the spheroids with EF5 and subsequent immunohistochemical staining of cryosections with an anti-EF5 fluorochrome conjugated monoclonal antibody allowed for the identification of EF5-adduct containing cells. Spheroids grown under hypoxic conditions in the presence of EF5 showed limited staining of the peripheral cell layers, intense staining of the interior, and an absence of staining within the necrotic center. In contrast, there was minimal staining in reoxygenated spheroids and no staining in control spheroids incubated in the absence of EF5. Flow cytometric analysis of single cells dissociated from spheroids allowed for the calculation of the percentage of stained cells, as well as the intensity of staining. A comparison of the intensity of staining of EF5 treated hypoxic spheroids with the intensity of staining of single cells incubated with EF5 under controlled oxygen concentrations was used to estimate the oxygen concentration range within spheroids. Selective dissociation of spheroids provided a direct demonstration that the cells containing the highest level of EF5 binding were also the cells with increased radiation resistance. CONCLUSION This technique provides an excellent means of detecting and quantifying hypoxia, which should be directly applicable in tumors.
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Affiliation(s)
- M L Woods
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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Bérubé LR, Harasiewicz K, Foster FS, Dobrowsky E, Sherar MD, Rauth AM. Use of a high frequency ultrasound microscope to image the action of 2-nitroimidazoles in multicellular spheroids. Br J Cancer 1992; 65:633-40. [PMID: 1586589 PMCID: PMC1977392 DOI: 10.1038/bjc.1992.137] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A system was designed to allow imaging of control and drug treated multicellular spheroids with a high frequency backscatter ultrasound microscope. It allowed imaging of individual spheroids under good growth conditions. Since little data were available on cellular toxicity of ultrasound at these high frequencies (80 MHz), studies were undertaken to evaluate effects on cell survival, using a colony forming assay. No toxicity was observed on cell monolayers subjected to pulsed ultrasound at the intensities used for imaging experiments. Spheroids were also subjected to pulsed ultrasound and no growth delay was observed when exposed spheroids were compared with mock-exposed spheroids. Imaging studies were performed and pictures of untreated spheroids were obtained in which the necrotic and viable regions are clearly distinguishable. When the hypoxic cell cytotoxin 1-methyl-2-nitroimidazole (INO2) was added to the spheroid, dramatic changes were observed in the backscatter signal. The interior viable cells of the spheroid were selectively affected. Changes in the backscatter signal were also observed when the reduction product 1-methyl-2-nitrosoimidazole (INO) was added to spheroids. With INO however, the changes were located at the periphery of the spheroid, presumably due to the high reactivity of INO which limits diffusion of the drug into the spheroid. The present work demonstrates the potential usefulness of ultrasound backscatter microscopy in following the action of selected drugs in this in vitro tumour model.
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Affiliation(s)
- L R Bérubé
- Ontario Cancer Institute, Toronto, Canada
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Sillerud LO, Freyer JP, Neeman M, Mattingly MA. Proton NMR Microscopy of Multicellular Tumor Spheroid Morphology. Magn Reson Med 1990. [DOI: 10.1002/j.1522-2594.1990.tb00001.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - James P. Freyer
- Cellular and Molecular Biology Group, Life Sciences DivisionLos Alamos National Laboratory, University of CaliforniaLos AlamosNew Mexico87545
| | - Michal Neeman
- Cellular and Molecular Biology Group, Life Sciences DivisionLos Alamos National Laboratory, University of CaliforniaLos AlamosNew Mexico87545
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Sillerud LO, Freyer JP, Neeman M, Mattingly MA. Proton NMR microscopy of multicellular tumor spheroid morphology. Magn Reson Med 1990; 16:380-9. [PMID: 2077329 DOI: 10.1002/mrm.1910160304] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We report proton NMR images obtained at microscopic (less than 30 microns) resolution of EMT6/Ro and HT1080 multicellular tumor spheroids 1.2-1.7 mm in diameter. T1-weighted images showed little contrast across a slice through the spheroid. There was also no difference between the inner and outer spheroid regions when signal intensity was measured as a function of the repetition time (TR), showing that T1 was the same across the spheroid. Conversely, T2-weighted and multi-echo images clearly revealed the central necrosis that occurs as the spheroids develop. Measurements of the thickness of the viable cell zone made on NMR images agreed with those made on standard histology sections for two different cell lines. The basis for the NMR discrimination of the necrotic region from the viable rim cells was found to be a shortened apparent T2 in the necrotic region (132 +/- 17 ms) with respect to that in the viable cells (173 +/- 9 ms). These results illustrate the applicability of NMR microscopy to assaying conditions inside intact tumor spheroids and suggest that this technology will allow the use of spheroids to investigate several important questions in tumor biology and pathophysiology.
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Affiliation(s)
- L O Sillerud
- Biomedical NMR Facility, Los Alamos National Laboratory, University of California, New Mexico 87545
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Paschen W. Imaging of energy metabolites (ATP, glucose and lactate) in tissue sections: a bioluminescent technique. PROGRESS IN HISTOCHEMISTRY AND CYTOCHEMISTRY 1990; 20:1-122. [PMID: 2315510 DOI: 10.1016/s0079-6336(11)80071-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- W Paschen
- Max-Planck-Institute for Neurological Research, Department of Experimental Neurology, Köln, FRG
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11
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Freyer JP, Schor PL. Automated selective dissociation of cells from different regions of multicellular spheroids. IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY : JOURNAL OF THE TISSUE CULTURE ASSOCIATION 1989; 25:9-19. [PMID: 2914820 DOI: 10.1007/bf02624405] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In this report we describe a new apparatus which has been developed for the automated selective dissociation of multicellular spheroids into fractions of viable cells from different locations in the spheroid. This device is based on the exposure of spheroids to a 0.25% solution of trypsin under carefully controlled conditions, such that the cells are released from the outer spheroid surface in successive layers. Study of the spheroid size, number of cells per spheroid, and sections through the spheroid with increasing exposure to trypsin demonstrate the effectiveness of this technique. The technique has been successfully used on spheroids from five different cell lines over a wide range of spheroid diameters. We also present data detailing the effect of varying the dissociation temperature, the mixing speed, the trypsin concentration, and the number of spheroids being dissociated. The new apparatus has several advantages over previous selective dissociation methods and other techniques for isolating cells from different regions in spheroids, including: a) precise control over dissociation conditions, improving reproducibility; b) short time to recover cell fractions; c) ability to isolate large numbers of cells from many different spheroid locations; d) use of common, inexpensive laboratory equipment; and e) easy adaptability to new cell lines or various spheroid sizes. Applications of this method are demonstrated, including the measurement of nutrient consumption rates, regrowth kinetics, and radiation survivals of cells from different spheroid regions.
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Affiliation(s)
- J P Freyer
- Life Sciences Division, Los Alamos National Laboratory, New Mexico 87545
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Freyer JP, Wilder ME, Jett JH. Viable sorting of intact multicellular spheroids by flow cytometry. CYTOMETRY 1987; 8:427-36. [PMID: 3304881 DOI: 10.1002/cyto.990080413] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A flow cytometric method has been developed for sorting viable, intact multicellular spheroids in order to obtain uniformly-sized populations with diameters in the range of 50-100 microns. A FACS II instrument was modified for this purpose by installing a 200-microns-diameter exit orifice and by making adjustments in the sheath flow, oscillator frequency, and number of droplets sorted. Polystyrene microspheres (44 and 88 microns diameter) and 41-96-microns-diameter spheroids could be sorted and recovered with 70-100% efficiency, an improvement over previous reports. Unstained, viable spheroids were simultaneously analyzed for small-angle forward light scatter, 90 degree light scatter, and autofluorescence using a 488-nm laser operating at 100 mW. Analysis of the data demonstrated a considerable variation in both the 90 degrees light scatter and the autofluorescence signals for a given forward angle light scattering signal. By setting narrow sort windows on the forward angle light scattering signal and either the 90 degree light scatter or autofluorescence signals, uniformly spherical spheroid populations could be recovered. These sorted populations had coefficients of variation of the mean diameter in the range of 5-9%. This represents a variation of less than one cell diameter, and is a major improvement over any other technique. There was no significant difference in the subsequent growth rates of sorted spheroids compared to the unsorted spheroids. This technique will apply when uniform populations of small spheroids are required, such as investigations of the contact effect or in the initiation of growth curve studies.
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Mueller-Klieser W. Multicellular spheroids. A review on cellular aggregates in cancer research. J Cancer Res Clin Oncol 1987; 113:101-22. [PMID: 3549738 DOI: 10.1007/bf00391431] [Citation(s) in RCA: 284] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Cellular aggregates have been used in developmental biology and in experimental cancer research for several decades. Spherical aggregates of malignant cells, i.e. multicellular tumor spheroids, may serve as in vitro models of tumor microregions and of an early, avascular stage of tumor growth. The similarities between the original tumor and the respective spheroids include volume growth kinetics, cellular heterogeneity, e.g. the induction of proliferation gradients and quiescence, as well as differentiation characteristics, such as the development of specific histological structures or the expression of antigens. Research using cell aggregates has been focussed on mechanisms involved in the control of proliferation, invasion and metastasis. Immunological studies with spheroids have resulted in the characterization of defense cells which are responsible for specific host-versus-tumor reactions. The vast majority of investigations on spheroids concerns the simulation of therapy with regard to various treatment modalities, combination treatments and systematic analyses of using various endpoints in predictive assays. Only a few pathophysiological studies on the interrelationship among tumor-specific micromilieu, cellular metabolism, proliferative status, and cellular viability have been undertaken with the spheroid model up to now. Since these studies are indicative of a large influence of the cellular microenvironment on basic biological properties of cancer cells, investigations of these epigenetic mechanisms should be intensified in future research on cell aggregates. Similarly, the molecular basis of the biological peculiarities found in malignant cells grown as three-dimensional aggregates has to be investigated more intensively.
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Mueller-Klieser W, Vaupel P. Improvement of tumor spheroid oxygenation by tetrachlorodecaoxide. Int J Radiat Oncol Biol Phys 1987; 13:49-54. [PMID: 3804815 DOI: 10.1016/0360-3016(87)90259-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The benefit of Tetrachlorodecaoxide (TCDO) in improving tumor tissue oxygenation has been tested using multicellular tumor spheroids. Measurements of oxygen tension (PO2) values with O2-sensitive microelectrodes revealed a distinct enhancement of the spheroid oxygenation after both, bolus injection or continuous infusion of TCDO into the medium surrounding the spheroids. The effect of TCDO on local oxygenation appeared to be less pronounced in spheroid regions with low initial PO2 values compared to well-oxygenated areas of these cellular aggregates. By continuously infusing TCDO into the measuring system, a sustained increase of local PO2 was obtained which was proportional to the local steady state concentration of TCDO in the medium surrounding the tumor spheroids. During experiments with TCDO in vivo, this substance should, therefore, be tested for its potential of improving the oxygenation status of solid tumors, and hence, of sensitizing tumors to classical treatments, such as radiotherapy.
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Mueller-Klieser W, Vaupel P. Tetrachlorodecaoxide improves the oxygenation status of multicellular tumor spheroids. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1986; 200:623-32. [PMID: 3799354 DOI: 10.1007/978-1-4684-5188-7_75] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The benefit of Tetrachlorodecaoxide (TCDO) in improving tumor tissue oxygenation has been tested using multicellular tumor spheroids. Measurements of PO2 values with O2-sensitive microelectrodes revealed a distinct enhancement of the spheroid oxygenation after bolus injection of TCDO into the medium around the spheroid (peak concentration: 0.7 mM). Small spheroids exhibited a uniform, transient rise in PO2 at different locations within the spheroid. Larger spheroids showed a smaller, yet still significant increase in PO2 in inner parts compared to the spheroid periphery. The increase in PO2 after TCDO injection appeared to be less in spheroid areas with low initial PO2 values versus well-oxygenated spheroid regions. Continuous infusion of TCDO for 15 minutes at steady state concentrations in the medium of 33 microM resulted in a substantial and persistent elevation of the local PO2 within spheroids. The PO2 returned to the control level 20 minutes after the stoppage of the infusion.
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Vaupel P, Mueller-Klieser W. Cell line and growth site as relevant parameters governing tumor tissue oxygenation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1986; 200:633-43. [PMID: 3799355 DOI: 10.1007/978-1-4684-5188-7_76] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Tumors commonly exhibit pronounced inter-individual and intra-individual differences in the oxygenation status. Paramount factors contributing to this variability are the tumor growth stage or size, changes in the O2 transport capacity of the arterial blood (e.g., during tumor-induced anemia) as well as inherent properties of the tumor cell line investigated and different tumor growth sites as shown in the present study. In most cases, variations of nutritive tumor blood flow and changes in the amount of arterio-venous shunt perfusion within the tumor tissue have to be considered as basic pathomechanisms for these inter-tumor variations of tissue oxygenation.
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