scholarly journals Quantitative analysis of tumour spheroid structure

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Alexander P Browning ◽  
Jesse A Sharp ◽  
Ryan J Murphy ◽  
Gency Gunasingh ◽  
Brodie Lawson ◽  
...  

Tumour spheroids are common in vitro experimental models of avascular tumour growth. Compared with traditional two-dimensional culture, tumour spheroids more closely mimic the avascular tumour microenvironment where spatial differences in nutrient availability strongly influence growth. We show that spheroids initiated using significantly different numbers of cells grow to similar limiting sizes, suggesting that avascular tumours have a limiting structure; in agreement with untested predictions of classical mathematical models of tumour spheroids. We develop a novel mathematical and statistical framework to study the structure of tumour spheroids seeded from cells transduced with fluorescent cell cycle indicators, enabling us to discriminate between arrested and cycling cells and identify an arrested region. Our analysis shows that transient spheroid structure is independent of initial spheroid size, and the limiting structure can be independent of seeding density. Standard experimental protocols compare spheroid size as a function of time; however, our analysis suggests that comparing spheroid structure as a function of overall size produces results that are relatively insensitive to variability in spheroid size. Our experimental observations are made using two melanoma cell lines, but our modelling framework applies across a wide range of spheroid culture conditions and cell lines.

2021 ◽  
Author(s):  
Alexander P Browning ◽  
Jesse A Sharp ◽  
Ryan J Murphy ◽  
Gency Gunasingh ◽  
Brodie Lawson ◽  
...  

Tumour spheroids are common in vitro experimental models of avascular tumour growth. Compared with traditional two-dimensional culture, tumour spheroids more closely mimic the avascular tumour microenvironment where spatial differences in nutrient availability strongly influence growth. We show that spheroids initiated using significantly different numbers of cells grow to similar limiting sizes, suggesting that avascular tumours have a limiting structure; in agreement with untested predictions of classical mathematical models of tumour spheroids. We develop a novel mathematical and statistical framework to study the structure of tumour spheroids seeded from cells transduced with fluorescent cell cycle indicators, enabling us to discriminate between arrested and cycling cells and identify an arrested region. Our analysis shows that transient spheroid structure is independent of initial spheroid size, and the limiting structure can be independent of seeding density. Standard experimental protocols compare spheroid size as a function of time; however, our analysis suggests that comparing spheroid structure as a function of overall size produces results that are relatively insensitive to variability in spheroid size. Our experimental observations are made using two melanoma cell lines, but our modelling framework applies across a wide range of spheroid culture conditions and cell lines.


Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 460
Author(s):  
Beatriz Medeiros-Fonseca ◽  
Antonio Cubilla ◽  
Haissa Brito ◽  
Tânia Martins ◽  
Rui Medeiros ◽  
...  

Penile cancer is an uncommon malignancy that occurs most frequently in developing countries. Two pathways for penile carcinogenesis are currently recognized: one driven by human papillomavirus (HPV) infection and another HPV-independent route, associated with chronic inflammation. Progress on the clinical management of this disease has been slow, partly due to the lack of preclinical models for translational research. However, exciting recent developments are changing this landscape, with new in vitro and in vivo models becoming available. These include mouse models for HPV+ and HPV− penile cancer and multiple cell lines representing HPV− lesions. The present review addresses these new advances, summarizing available models, comparing their characteristics and potential uses and discussing areas that require further improvement. Recent breakthroughs achieved using these models are also discussed, particularly those developments pertaining to HPV-driven cancer. Two key aspects that still require improvement are the establishment of cell lines that can represent HPV+ penile carcinomas and the development of mouse models to study metastatic disease. Overall, the growing array of in vitro and in vivo models for penile cancer provides new and useful tools for researchers in the field and is expected to accelerate pre-clinical research on this disease.


Blood ◽  
2020 ◽  
Vol 136 (22) ◽  
pp. 2535-2547 ◽  
Author(s):  
W. Grey ◽  
R. Chauhan ◽  
M. Piganeau ◽  
H. Huerga Encabo ◽  
M. Garcia-Albornoz ◽  
...  

Abstract Expansion of human hematopoietic stem cells (HSCs) is a rapidly advancing field showing great promise for clinical applications. Recent evidence has implicated the nervous system and glial family ligands (GFLs) as potential drivers of hematopoietic survival and self-renewal in the bone marrow niche; how to apply this process to HSC maintenance and expansion has yet to be explored. We show a role for the GFL receptor, RET, at the cell surface of HSCs in mediating sustained cellular growth, resistance to stress, and improved cell survival throughout in vitro expansion. HSCs treated with the key RET ligand/coreceptor complex, glial-derived neurotrophic factor and its coreceptor, exhibit improved progenitor function at primary transplantation and improved long-term HSC function at secondary transplantation. Finally, we show that RET drives a multifaceted intracellular signaling pathway, including key signaling intermediates protein kinase B, extracellular signal-regulated kinase 1/2, NF-κB, and p53, responsible for a wide range of cellular and genetic responses that improve cell growth and survival under culture conditions.


1983 ◽  
Vol 3 (4) ◽  
pp. 596-604
Author(s):  
C A Whitlock ◽  
S F Ziegler ◽  
O N Witte

Some molecular changes which correlate with the tumorigenic progression of neoplastic cells can best be studied with in vitro cell lines that represent each stage in the progression. Lymphoid cells infected by Abelson murine leukemia virus exhibit a wide range of growth potential in vitro and in vivo. Uncloned populations that are poorly oncogenic early after infection become progressively more oncogenic with successive passages of the cells in culture. In such mass cultures, it is difficult to evaluate whether a rare subpopulation of highly oncogenic cells becomes dominant in the culture or whether the individual cells progress in oncogenic phenotype. To examine this latter possibility, Abelson virus-infected lymphoid cells were cloned by limiting-dilution culture 10 days postinfection. We isolated two clones that grew poorly in agar, required feeder layers of adherent bone marrow cells for growth in liquid culture, and were extremely slow to form tumors in syngeneic animals. Both clones, after passage in the presence of adherent feeder layers for 3 months, grew well in liquid and agar-containing cultures in the absence of feeder layers and formed tumors in animals at a rapid rate. The progression of these clonal cell lines to a more malignant growth phenotype occurred in the absence of detectable changes in the concentration, half-life, phosphorylation, in vitro kinase activity, or cell localization of the Abelson virus-encoded transforming protein. No change in the concentration or arrangement of integrated Abelson viral DNA sequences was detected in either clone. Thus, perhaps changes in the expression of cellular genes would appear to alter the growth properties of lymphoid cells after their initial transformation by Abelson virus. Such cellular changes could complement the activity of the Abelson virus transforming protein in producing the fully malignant growth phenotype.


2005 ◽  
Vol 17 (2) ◽  
pp. 167 ◽  
Author(s):  
A.M. Giraldo ◽  
J.W. Lynn ◽  
C.E. Pope ◽  
R.A. Godke ◽  
K.R. Bondioli

The low efficiency of nuclear transfer (NT) has been related to factors such as mitochondria heteroplasmy, failure of genomic activation, and asynchrony between the donor karyoplast and recipient cytoplast. Few studies have characterized donor cell lines in terms of proliferative capacity and chromosomal stability. It is known that suboptimal culture conditions can induce chromosomal abnormalities, and the use of aneuploid donor cells during NT can lead to a high incidence of abnormal cloned embryos (Giraldo et al. 2004 Reprod. Fertil. Dev. 16, 124 abst). The purpose of this study was to determine the lifespan and chromosomal stability of bovine and porcine fetal cells. Four bovine and four porcine fibroblast cells lines were established from 50-day and 40-day fetuses, respectively. Cells were cultured in DMEM medium supplemented with 10% fetal bovine serum and 1% penicillin and streptomycin at 37°C in 5% CO2. Each cell line was passaged to senescence. Total population doublings (PDs) and cell cycle duration were calculated. To determine the chromosome numbers at different PDs, cells were synchronized in metaphase, fixed, and stained. ANOVA and chi-square tests were used to analyze differences in PDs and proportion of aneuploid cells between cell lines, respectively (P < 0.05). The results show that proliferative capacity was not different between cell lines derived from the same species. Cell lines derived from bovine and porcine fetuses had different in vitro lifespans (33 PDs vs. 42 PDs, respectively; P < 0.05). The mean length of the cell cycles for both bovine and porcine fetal fibroblasts was ∼28 h. The percentage of aneupliod cells in both bovine and porcine fetal cell lines increased progressively with duration of culture (see Table) and was high throughout the study. The proliferative capacity of cultured cells was similar within individuals of the same species, but growth characteristics differed between fetal bovine and porcine cell lines. The progressive increase of aneuploid cells could be due to suboptimal culture conditions or unusual chromosome instability in the particular fetuses used. These data demonstrate the importance of determining chromosome content and the use of cells at early passages to decrease the percentage of aneuploid reconstructed embryos and increase the efficiency of NT.


2018 ◽  
Vol 10 (5) ◽  
pp. 153 ◽  
Author(s):  
Balashanmugam P. ◽  
Mosa Christas K. ◽  
Kowsalya E.

Objective: The biogenic gold nanoparticles are considered to be extremely impressive for its wide range of applications in pharmaceutics and therapeutics. The present study was aimed at the biogenic synthesis of gold nanoparticles (AuNPs) from Marsilea quadrifolia aqueous extract and to investigate its antioxidant property and cytotoxic effect on human ovarian teratocarcinoma (PA-1) and lung adenocarcinoma (A549) cell lines.Methods: The biogenic AuNPs was synthesized using an aqueous extract of Marsilea quadrifolia. The synthesized biogenic AuNPs were characterized by ultraviolet (UV) visible spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD). The biogenic AuNPs was assessed for its stability over a period of time and antioxidant activity. The cytotoxicity of biogenic AuNPs against PA-1 and A549 cell lines was studied using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.Results: The synthesized biogenic AuNPs showed peculiar ruby red color and a surface plasmon resonance (SPR) peak at 544 nm in the UV-Vis spectrum. The characterization of biogenic AuNPs by TEM, EDX and XRD revealed well dispersed spherical particles ranging from 10-40 nm and the presence of elemental gold and its crystalline nature, respectively. The AuNPs showed good stability and the scavenging activity at 50 μg/ml. The in vitro cytotoxicity of biogenic AuNPs against PA-1 and A549 cell lines recorded half maximal inhibitory concentration (IC50) of 45.88 μg/ml and 52.015 μg/ml, respectively.Conclusion: The biogenic AuNPs demonstrated superior antioxidant and antiproliferative activities against cancer cell lines.


Antioxidants ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 609 ◽  
Author(s):  
Amjad Khan ◽  
Muhammad Ikram ◽  
Jong Ryeal Hahm ◽  
Myeong Ok Kim

Neurodegenerative disorders have emerged as a serious health issue in the current era. The most common neurodegenerative disorders are Alzheimer’s disease (AD), Parkinson’s disease, multiple sclerosis, and amyotrophic lateral sclerosis (ALS). These diseases involve progressive impairment of neurodegeneration and memory impairment. A wide range of compounds have been identified as potential neuroprotective agents against different models of neurodegeneration both in vivo and in vitro. Hesperetin, a flavanone class of citrus flavonoid, is a derivative of hesperidin found in citrus fruits such as oranges, grapes, and lemons. It has been extensively reported that hesperetin exerts neuroprotective effects in experimental models of neurodegenerative diseases. In this systematic review, we have compiled all the studies conducted on hesperetin in both in vivo and in vitro models of neurodegeneration. Here, we have used an approach to lessen the bias in each study, providing a least biased, broad understanding of findings and impartial conclusions of the strength of evidence and the reliability of findings. In this review, we collected different papers from a wide range of journals describing the beneficial effects of hesperetin on animal models of neurodegeneration. Our results demonstrated consistent neuroprotective effects of hesperetin against different models of neurodegeneration. In addition, we have summarized its underlying mechanisms. This study provides the foundations for future studies and recommendations of further mechanistic approaches to conduct preclinical studies on hesperetin in different models.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1571-1571 ◽  
Author(s):  
Thomas Prebet ◽  
Anne Catherine Lhoumeau ◽  
Christine Arnoulet ◽  
Anais Aulas ◽  
Sylvie Marchetto ◽  
...  

Abstract Abstract 1571 Poster Board I-596 The pseudo tyrosine kinase receptor 7 (PTK7) is an orphean tyrosine kinase receptor assigned to the planar cell polarity pathway (PCP). It has been recently described and plays a major role during embryogenesis and epithelial tissue organisation. To date there is no report in the litterature considering a potential implication in hematopoiesis. In silico and in vitro analysis found that PTK7 was also expressed in normal myeloid progenitors and CD34+ CD38- bone marrow cells in humans. Preliminary results from our team showed that PTK7 was also expressed in various leukemic cell lines such Jurkat, TF-1 or KG-1a. We decided to perform a wide range multicolour immunophenotyping screen on patients with acute myeloid leukemia (AML) at diagnosis and to investigate the role of PTK7 in AML in vitro. More than 250 patient samples were evaluated and we demonstrated that PTK7 was largely expressed in AML as 72% of the samples were PTK7 positive. Its expression mostly correlates with granulocytic lineage differentiation. PTK7 expression was associated with a lower WBC count at diagnosis and a lower frequency of extramedullary disease whatever was FAB subtype. Interestingly, PTK7 expression was associated with some cytogenetic subgroups including CBF-AML and APL. There was no correlation with molecular subgroups (i.e. FLT3-ITD/NPM1/CEBPA status). Overall Survival and Relapse Free Survival were evaluated in non-APL patients treated with induction chemo (n=182). Patients with PTK7 positive AML are more resistant to anthracycline-based frontline therapy with a significantly reduced Relapse Free Survival in a multivariate analysis model integrating all pre treatment variables (2 year probability of RFS= 29% vs 66% for PTK7 negative patients, p= 0.003). Forrest plot analysis showed that the negative impact of PTK7 expression was the most significant in intermediate cytogenetic risk subgroup and when PTK7 was aberrantly expressed in M4-M5 FAB subtypes. There was no demonstrated impact on CR. In cultured cells, expression of PTK7 promotes leukemia cell migration, cell survival and resistance to anthracyclin-induced apoptosis. There was no effect of PTK7 expression on cell proliferation in tritiated thymidine assay. In the absence of known inhibitor of PTK7, we produced a soluble recombinant PTK7-Fc protein that efficiently competes for PTK7 functions in cell migration and survival assays in cell lines and primary AML samples. These data were confirmed using a shRNA strategy. We conclude that PTK7 is a PCP component expressed in the myeloid progenitor compartment that conveys promigratory and anti-apoptotic signal to leukemia cells. Its use as a potential biomarker or therapeutical target should be investigated. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2888-2888
Author(s):  
Abhinav B. Chandra ◽  
Jack Burton ◽  
Rhona Stein ◽  
Susan Chen ◽  
Nidhi Mishra ◽  
...  

Abstract Abstract 2888 Background: CD74 (HLA-DR-associated invariant chain) is expressed alone or along with DR in a wide range of hematologic cancers and solid tumors. Humanized anti-CD74 mAb, milatuzumab (Immunomedics, Morris Plains, NJ), exhibits direct cytotoxicity for NHL, CLL and MM cell lines, and is undergoing clinical evaluation for treatment of these malignancies. CD74 is upregulated by interferons in hematologic and epithelial cancer cell lines. Here we present the results of our analysis of CD74 expression and function in AML, and the effect of CD74 upregulation by treatment with IFN-γ on the cytotoxicity of milatuzumab for AML cell lines. Methods: CD74 expression in bone marrow biopsy (BMB) specimens from non-M3 AML patients was evaluated by immunohistochemistry and, for the 3 human AML cell lines, by flow cytometry, with/without permeabilization and with/without IFN-γ (40 and 200 U/mL). These cell lines were also tested in proliferation assays for responses to milatuzumab, with/without IFN-γ. Also, assessment of apoptosis and cellular signaling was performed. Results: In the initial group of AML cases, 13/14 BMB specimens showed moderate to strong CD74 expression by leukemic blasts, which was mostly intracellular, usually with a perinuclear distribution. Three AML cell lines also showed moderate to strong expression of CD74, which was mostly intracellular. Without IFN-γ, surface expression of CD74 was present, but IFN-γ treatment of these 3 lines resulted in upregulation of surface CD74 by 69–117%. Much higher levels of intracellular CD74 were observed in all 3 lines (with and without IFN-γ), with IFN-γ-induced upregulation of intracellular CD74 in all 3 lines (from 85%-868%; P<0.001). In 2/3 lines, IFN-γ increased milatuzumab-mediated growth inhibition (23.7 to 44.8% and -3.9 to 30.9%, P=0.01 and P<0.05, respectively). Cytotoxicity was in part due to apoptosis, as significant increases in Annexin V binding (P=0.01) were observed after treatment with IFN-γ plus milatuzumab. Initial experiments addressing cellular signaling suggest a role for AKT, because phosphorylated AKT levels increased (P=0.06) in response to IFN-γ + milatuzumab. Conclusions: CD74 is expressed in AML patient specimens and in AML cell lines, with the majority of CD74 expression found intracellularly. Cell surface and cytoplasmic expression of CD74 were upregulated in AML lines after IFN-γ exposure. This increased expression resulted in increased cytotoxicity of the anti-CD74 mAb, milatuzumab, in 2/3 AML lines. This effect was through apoptosis and involved the AKT pathway. Thus, AML is another cancer type where combined IFN-γ and milatuzumab treatment may be useful. Supported in part by NIH grant PO1-CA103985 (DMG). Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3436-3436
Author(s):  
Amit Kumar Mitra ◽  
Taylor S Harding ◽  
Brian Van Ness

Abstract Proteasome inhibitors (PI) are effective chemotherapeutic agents in the treatment of multiple myeloma (MM), used alone or in combination with other anti-cancer agents, such as alkylating agents, topoisomerase inhibitors, corticosteroids, histone deacetylase inhibitors (HDACis) and immunomodulatory drugs (IMiDs). Bortezomib (Velcade/Bz) was the first PI to be approved by US-FDA for the treatment of relapsed and refractory MM. Other second generation PIs include carfilzomib (Kyprolis/Cz), ixazomib/Iz and oprozomib (Opz). Wide inter-individual variation in response to treatment with PIs is a major limitation in achieving consistent therapeutic effect in MM. Yet few studies have compared the efficacy of all four PIs in a range of myeloma subtypes. In our current study, we performed comprehensive in vitro chemosensitivity profiling of response to four (4) PIs (Bz, Cz, Ix and Opz) in a panel of forty-five (45) human myeloma cells lines (HMCLs) generated through the immortalization of primary multiple myeloma cells (MMCs) and representing the biological and genetic heterogeneity of MM with regards to chromosomal abnormalities, oncogene mutations (e.g. Ras), tumor suppressor variations (e.g. p53), cell surface phenotypes, or growth factor response. Cells were treated with increasing concentrations of Bz, Cz, Ix and Opz as single agents and cell viability assays were performed using CellTiter-Glo luminescent cell viability assay to generate survival curves and determine the half maximal inhibitory concentration (IC50) values by calculating the nonlinear regression using sigmoidal dose-response equation (variable slope). Our results in comparing the cellular responses to PI treatment among HMCLs showed wide range of variability in IC50 values identifying some lines which were highly sensitive and some lines relatively refractory to PI treatment. Pearson product-moment correlation (PPMC) test demonstrated statistically significant (adjusted p values < 0.001) positive correlation between IC50 values of the following drug pairs: Bz vs Opz (r = 0.82); and Ix vs Opz (r = 0.88); Bz vs Ix (r = 0.65); Cz vs Opz (r = 0.69) and Cz vs Ix (r = 0.63). Subgroup analysis revealed significant correlation between carfizomib IC50 and chromosome number (p < 0.05). Furthermore, it was interesting to note that although all 4 drugs belong to the same drug class (PI), not all cell lines responded the same across all PI treatments. This demonstrates tumor heterogeneity even in response to inhibitors of the same class, and further demonstrates tumors refractory to one PI may still respond to another. We are currently examining genetic characteristics that are associated with response among the four PIs, and analysis of these characteristics will be presented. Disclosures No relevant conflicts of interest to declare.


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