scholarly journals Designing and interpreting 4D tumour spheroid experiments

2021 ◽  
Author(s):  
Ryan J Murphy ◽  
Alexander P Browning ◽  
Gency Gunasingh ◽  
Nikolas K Haass ◽  
Matthew J Simpson

Tumour spheroid experiments are routinely used to study cancer progression and treatment. Various and inconsistent experimental designs are used, leading to challenges in interpretation and reproducibility. Using multiple experimental designs, live-dead cell staining, and real-time cell cycle imaging, we measure necrotic and proliferation-inhibited regions in over 1000 4D tumour spheroids (3D space plus cell cycle status). By intentionally varying the initial spheroid size and temporal sampling frequencies across multiple cell lines, we collect an abundance of measurements of internal spheroid structure. These data are difficult to compare and interpret. However, using an objective mathematical modelling framework and statistical identifiability analysis we quantitatively compare experimental designs and identify design choices that produce reliable biological insight. Measurements of internal spheroid structure provide the most insight, whereas varying initial spheroid size and temporal measurement frequency is less important. Our general framework applies to spheroids grown in different conditions and with different cell types.

Dose-Response ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 155932582092868 ◽  
Author(s):  
Qingjie Xian ◽  
Ronglei Zhao ◽  
Juanjuan Fu

Increasing evidence indicated that microRNAs served dominant roles in carcinogenesis and cancer progression by targeting potential downstream genes. In our study, we found that miR-527 was an upregulated expression in human esophageal squamous cell carcinoma (ESCC) cells and tissues. Furthermore, overexpression of miR-527 promoted cell proliferation and colony formation, enhanced anchorage-independent growth ability, and contributed to cell cycle. In addition, protein phosphatase 2 (PHLPP2) was identified as the direct downstream target gene of miR-527 and was confirmed by luciferase gene reporter assay. In summary, we concluded that miR-527 acted as an oncogenic microRNA in ESCC development by directly targeting PHLPP2 might be a novel therapeutic target for the treatment of ESCC.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Susanne Fransson ◽  
Angela Martinez-Monleon ◽  
Mathias Johansson ◽  
Rose-Marie Sjöberg ◽  
Caroline Björklund ◽  
...  

AbstractNeuroblastoma is the most common and deadly childhood tumor. Relapsed or refractory neuroblastoma has a very poor prognosis despite recent treatment advances. To investigate genomic alterations associated with relapse and therapy resistance, whole-genome sequencing was performed on diagnostic and relapsed lesions together with constitutional DNA from seven children. Sequencing of relapsed tumors indicates somatic alterations in diverse genes, including those involved in RAS-MAPK signaling, promoting cell cycle progression or function in telomere maintenance and immortalization. Among recurrent alterations, CCND1-gain, TERT-rearrangements, and point mutations in POLR2A, CDK5RAP, and MUC16 were shown in ≥ 2 individuals. Our cohort contained examples of converging genomic alterations in primary-relapse tumor pairs, indicating dependencies related to specific genetic lesions. We also detected rare genetic germline variants in DNA repair genes (e.g., BARD1, BRCA2, CHEK2, and WRN) that might cooperate with somatically acquired variants in these patients with highly aggressive recurrent neuroblastoma. Our data indicate the importance of monitoring recurrent neuroblastoma through sequential genomic characterization and that new therapeutic approaches combining the targeting of MAPK signaling, cell cycle progression, and telomere activity are required for this challenging patient group.


Nutrients ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 1212
Author(s):  
Getinet M. Adinew ◽  
Equar Taka ◽  
Patricia Mendonca ◽  
Samia S. Messeha ◽  
Karam F. A. Soliman

Triple- negative breast cancer (TNBC) incidence rate has regularly risen over the last decades and is expected to increase in the future. Finding novel treatment options with minimum or no toxicity is of great importance in treating or preventing TNBC. Flavonoids are new attractive molecules that might fulfill this promising therapeutic option. Flavonoids have shown many biological activities, including antioxidant, anti-inflammatory, and anticancer effects. In addition to their anticancer effects by arresting the cell cycle, inducing apoptosis, and suppressing cancer cell proliferation, flavonoids can modulate non-coding microRNAs (miRNAs) function. Several preclinical and epidemiological studies indicate the possible therapeutic potential of these compounds. Flavonoids display a unique ability to change miRNAs’ levels via different mechanisms, either by suppressing oncogenic miRNAs or activating oncosuppressor miRNAs or affecting transcriptional, epigenetic miRNA processing in TNBC. Flavonoids are not only involved in the regulation of miRNA-mediated cancer initiation, growth, proliferation, differentiation, invasion, metastasis, and epithelial-to-mesenchymal transition (EMT), but also control miRNAs-mediated biological processes that significantly impact TNBC, such as cell cycle, immune system, mitochondrial dysregulation, modulating signaling pathways, inflammation, and angiogenesis. In this review, we highlighted the role of miRNAs in TNBC cancer progression and the effect of flavonoids on miRNA regulation, emphasizing their anticipated role in the prevention and treatment of TNBC.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
John A. Halsall ◽  
Simon Andrews ◽  
Felix Krueger ◽  
Charlotte E. Rutledge ◽  
Gabriella Ficz ◽  
...  

AbstractChromatin configuration influences gene expression in eukaryotes at multiple levels, from individual nucleosomes to chromatin domains several Mb long. Post-translational modifications (PTM) of core histones seem to be involved in chromatin structural transitions, but how remains unclear. To explore this, we used ChIP-seq and two cell types, HeLa and lymphoblastoid (LCL), to define how changes in chromatin packaging through the cell cycle influence the distributions of three transcription-associated histone modifications, H3K9ac, H3K4me3 and H3K27me3. We show that chromosome regions (bands) of 10–50 Mb, detectable by immunofluorescence microscopy of metaphase (M) chromosomes, are also present in G1 and G2. They comprise 1–5 Mb sub-bands that differ between HeLa and LCL but remain consistent through the cell cycle. The same sub-bands are defined by H3K9ac and H3K4me3, while H3K27me3 spreads more widely. We found little change between cell cycle phases, whether compared by 5 Kb rolling windows or when analysis was restricted to functional elements such as transcription start sites and topologically associating domains. Only a small number of genes showed cell-cycle related changes: at genes encoding proteins involved in mitosis, H3K9 became highly acetylated in G2M, possibly because of ongoing transcription. In conclusion, modified histone isoforms H3K9ac, H3K4me3 and H3K27me3 exhibit a characteristic genomic distribution at resolutions of 1 Mb and below that differs between HeLa and lymphoblastoid cells but remains remarkably consistent through the cell cycle. We suggest that this cell-type-specific chromosomal bar-code is part of a homeostatic mechanism by which cells retain their characteristic gene expression patterns, and hence their identity, through multiple mitoses.


2021 ◽  
Vol 83 (5) ◽  
Author(s):  
Wang Jin ◽  
Loredana Spoerri ◽  
Nikolas K. Haass ◽  
Matthew J. Simpson

2004 ◽  
Vol 15 (11) ◽  
pp. 5172-5186 ◽  
Author(s):  
Moe R. Mahjoub ◽  
M. Qasim Rasi ◽  
Lynne M. Quarmby

Polycystic kidney disease and related syndromes involve dysregulation of cell proliferation in conjunction with ciliary defects. The relationship between cilia and cell cycle is enigmatic, but it may involve regulation by the NIMA-family of kinases (Neks). We previously showed that the Nek Fa2p is important for ciliary function and cell cycle in Chlamydomonas. We now show that Fa2p localizes to an important regulatory site at the proximal end of cilia in both Chlamydomonas and a mouse kidney cell line. Fa2p also is associated with the proximal end of centrioles. Its localization is dynamic during the cell cycle, following a similar pattern in both cell types. The cell cycle function of Fa2p is kinase independent, whereas its ciliary function is kinase dependent. Mice with mutations in Nek1 or Nek8 have cystic kidneys; therefore, our discovery that a member of this phylogenetic group of Nek proteins is localized to the same sites in Chlamydomonas and kidney epithelial cells suggests that Neks play conserved roles in the coordination of cilia and cell cycle progression.


1979 ◽  
Vol 81 (1) ◽  
pp. 123-136 ◽  
Author(s):  
N Agabian ◽  
M Evinger ◽  
G Parker

An essential event in developmental processes is the introduction of asymmetry into an otherwise undifferentiated cell population. Cell division in Caulobacter is asymmetric; the progeny cells are structurally different and follow different sequences of development, thus providing a useful model system for the study of differentiation. Because the progeny cells are different from one another, there must be a segregation of morphogenetic and informational components at some time in the cell cycle. We have examined the pattern of specific protein segregation between Caulobacter stalked and swarmer daughter cells, with the rationale that such a progeny analysis would identify both structurally and developmentally important proteins. To complement the study, we have also examined the pattern of protein synthesis during synchronous growth and in various cellular fractions. We show here, for the first time, that the association of proteins with a specific cell type may result not only from their periodicity of synthesis, but also from their pattern of distribution at the time of cell division. Several membrane-associated and soluble proteins are segregated asymmetrically between progeny stalked and swarmer cells. The data further show that a subclass of soluble proteins becomes associated with the membrane of the progeny stalked cells. Therefore, although the principal differentiated cell types possess different synthetic capabilities and characteristic proteins, the asymmetry between progeny stalked and swarmer cells is generated primarily by the preferential association of specific soluble proteins with the membrane of only one daughter cell. The majority of the proteins which exhibit this segregation behavior are synthesized during the entire cell cycle and exhibit relatively long, functional messenger RNA half-lives.


2004 ◽  
Vol 39 (Supplement 1) ◽  
pp. S58
Author(s):  
R. Troncone ◽  
I. Caputo ◽  
M. Barone ◽  
S. Auricchio ◽  
C. Esposito

Author(s):  
Esak Lee ◽  
Niranjan B. Pandey ◽  
Aleksander S. Popel

Tumour and organ microenvironments are crucial for cancer progression and metastasis. Crosstalk between multiple non-malignant cell types in the microenvironments and cancer cells promotes tumour growth and metastasis. Blood and lymphatic endothelial cells (BEC and LEC) are two of the components in the microenvironments. Tumour blood vessels (BV), comprising BEC, serve as conduits for blood supply into the tumour, and are important for tumour growth as well as haematogenous tumour dissemination. Lymphatic vessels (LV), comprising LEC, which are relatively leaky compared with BV, are essential for lymphogenous tumour dissemination. In addition to describing the conventional roles of the BV and LV, we also discuss newly emerging roles of these endothelial cells: their crosstalk with cancer cells via molecules secreted by the BEC and LEC (also called angiocrine and lymphangiocrine factors). This review suggests that BEC and LEC in various microenvironments can be orchestrators of tumour progression and proposes new mechanism-based strategies to discover new therapies to supplement conventional anti-angiogenic and anti-lymphangiogenic therapies.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Hongyu Zhao ◽  
Yu Teng ◽  
Wende Hao ◽  
Jie Li ◽  
Zhefeng Li ◽  
...  

Abstract Background Ovarian cancer was one of the leading causes of female deaths. Patients with OC were essentially incurable and portends a poor prognosis, presumably because of profound genetic heterogeneity limiting reproducible prognostic classifications. Methods We comprehensively analyzed an ovarian cancer single-cell RNA sequencing dataset, GSE118828, and identified nine major cell types. Relationship between the clusters was explored with CellPhoneDB. A malignant epithelial cluster was confirmed using pseudotime analysis, CNV and GSVA. Furthermore, we constructed the prediction model (i.e., RiskScore) consisted of 10 prognosis-specific genes from 2397 malignant epithelial genes using the LASSO Cox regression algorithm based on public datasets. Then, the prognostic value of Riskscore was assessed with Kaplan–Meier survival analysis and time-dependent ROC curves. At last, a series of in-vitro assays were conducted to explore the roles of IL4I1, an important gene in Riskscore, in OC progression. Results We found that macrophages possessed the most interaction pairs with other clusters, and M2-like TAMs were the dominant type of macrophages. C0 was identified as the malignant epithelial cluster. Patients with a lower RiskScore had a greater OS (log-rank P < 0.01). In training set, the AUC of RiskScore was 0.666, 0.743 and 0.809 in 1-year, 3-year and 5-year survival, respectively. This was also validated in another two cohorts. Moreover, downregulation of IL4I1 inhibited OC cells proliferation, migration and invasion. Conclusions Our work provide novel insights into our understanding of the heterogeneity among OCs, and would help elucidate the biology of OC and provide clinical guidance in prognosis for OC patients.


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