Cancer research
Live-cell imaging
in cancer research
Cancer is characterized as a complex disease that results from a series of successive genetic mutations, leading to defective cell functions and proliferation. The development of novel scientific techniques, alongside the optimization of already existing approaches drives the advancement of cancer research.
Live-cell microscopy has become an indispensable tool for improving our understanding of cancer pathogenesis. The applications of time-lapse imaging range from directly visualizing the transient interactions between immune and cancer cells, to examining more complex biological processes, such as metastasis, programmed cell death and tumor angiogenesis.
Multi-well clonogenic assay to evaluate cytotoxicity and genotoxicity of anti-cancer agents
Label-free, semi-automated assessment of cell survival and colony formation
Clonogenic or colony formation assay is a widely used method in the field of cancer biology. It evaluates the effects of different treatments on the ability of cancer cells to survive and form colonies. Standard clonogenic protocols involve colony fixation, staining and examination at the end of a lengthy incubation period. The CytoSMART Omni allows continuous monitoring of clonogenic growth by creating time-lapse videos for days or even weeks at a time, without the need to fix or stain your cells. Monitoring the entire process of colony formation can provide a lot of valuable information, including the time-dependent effects of different drug treatments. In addition, the integrated image analysis software automatically detects newly formed colonies and evaluates their size and circularity.
Fluorescence live-cell microscopy in cancer immunotherapy
Labelled imaging of cell-cell interactions
Cancer immunotherapy harnesses the inherent capabilities of the host immune system to combat cancer. Fluorescence microscopy has been playing a key role in facilitating the understanding of interactions that take place between immune and tumor cells, as this cellular interplay represents the core of any immunotherapeutic approach. The CytoSMART Lux3 FL fluorescence imaging system can capture spatial interactions between different types of cells by gathering kinetic data in real time. As the imaging can take place directly from inside an incubator, cellular interactions are not affected by undesired extrinsic factors.
In vitro cell migration assay for studying cancer metastasis
Algorithm-based analysis of cell migration
Cancer metastasis involves the spread of malignant cells from their original site and is responsible for the largest number of cancer-related deaths. Numerous in vitro assays have been developed to replicate different stages of metastasis under a more controlled environment. Scratch assays (also known as a wound healing assays), in particular, can aid the analysis of cancer cell migration under the influence of various chemokines and growth factors. All CytoSMART live-cell imaging platforms (CytoSMART Omni, Lux2 or Lux3 FL) are equipped with the Scratch Assay software that can analyse the rate and efficiency of scratch closure and cell migration.
3D cell cultures for cancer modelling
Tumor organoids represent a more sophisticated model for cancer research, as they more accurately mimic the genetic, cellular, and pathophysiological characteristics of cancer compared to traditional 2D cell cultures. CytoSMART Technologies has developed effective solutions for working with tumor-derived organoids. The CytoSMART Omni bright-field imaging system can closely monitor the process of tumor organoid formation by recording whole-vessel time-lapse videos directly from inside an incubator. The Corning Cell Counter, adapted with the innovative Organoid Counting software, can determine the precise number and size of organoids in a sample in no time.
Videos
Appnotes
Cell Cytoxicity Assay to Analyze Drug Response
Cell Viability Analysis
Cell Cytoxicity Assay to Analyze Drug Response
The effect of drugs and drug candidates on the viability of cells in culture can be determined using cell counting, live/dead assays and metabolic assays. However, these assays are often end-point measurements. Alternatively, cells can be monitored using bright-field microscopy, by creating time-lapse videos for a culture period of multiple days. To study the lasting effect of the drug candidate.
In this study the cytotoxic effect of a chemotherapy drug was investigated for a range of concentrations. The effect on cell viability between drug concentrations was compared by analyzing confluency measurements obtained using automated live-cell imaging. The entire experiment was performed inside a CO2-incubator, ensuring optimal culturing conditions and cells were imaged every hour for a period of 3 days.
Cell Migration
Cell migration is essential for physiological development and homeostasis, among other things. It is part of processes such as angiogenesis and wound healing. Conversely, cell migration in pathologies, including cancer can lead to worsening and progression of the diseased state.
To gain insight into collective cell migration a variety of assays have been developed. One of which is the wound healing assay, also known as the scratch assay. In this procedure a ‘wound’ is made in a confluent monolayer of cells, after which the gap closure is quantitatively monitored.
For this study a wound healing assay was performed to assess the effect of a chemotherapy drug on the migration of C6 rat glail tumor cells. Automated live-cell imaging was performed inside a CO2-incubator to ensure cells are kept at the desired conditions during the entire experiment. The experiment was performed in a 24 well plate, which was fully imaged every hour for 23 hours. The surface area and gap closure speed were compared for increasing concentrations of the drug.
Cell Viability Analysis
Cell viability, growth and cytotoxicity studies can be performed using metabolic activity assays. The overall metabolic activity of the cell is indicated by the enzymatic cleavage of colorimetric or fluorescent substrates.
While these assays are relatively straightforward and cheap, they are dependent on culture conditions and intrinsic metabolic activity of the cell type that is being investigated. Furthermore, depletion of the metabolic substrate can lead to a plateau in the fluorescent signal, making assay output unreliable. To overcome these limitations cell viability could be determined optically using confluency measurements.
In the study described here the performance of confluency measurements to assess cell viability were compared to a metabolic activity assay: cell titer blue. Confluency was visualized using automated bright-field microscopy and subsequently analyzed using image analysis algorithms. Images were collected inside a CO2-incubator, keeping the culture at optimal conditions. For the cell titer blue assay resazurin was added to the medium and incubated for 3 hours. The fluorescent signal was normalized to the control to obtain the relative metabolic activity as a measure of cell viability. The comparison between the methods was performed for two pancreatic cancer cell lines, PACO7 and POCA43.