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Quantification of Cytokine-Induced Cell Death in Human Colonic Organoids Using Live Fluorescence Microscopy
Published on: August 2, 2024
Modulating cell-to-cell variability and sensitivity to death ligands by co-drugging
Deborah A Flusberg1, Peter K Sorger
1Center for Cell Decision Processes, Department of Systems Biology, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA.
Physical Biology
|June 6, 2013
Summary
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) shows variable anti-cancer effects due to cell-to-cell differences. Combining drugs can tune this variability and enhance apoptosis, offering a promising therapeutic strategy.
Area of Science:
- Cancer Biology
- Cellular Signaling
- Pharmacology
Background:
- Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anti-cancer agent, but its efficacy is limited by variable apoptosis induction across tumor cell lines.
- Fractional cell killing by TRAIL, even in clonal populations, is attributed to cell-to-cell variability in gene expression and protein levels, not genetic differences.
- Understanding and modulating this cell-to-cell variability is crucial for optimizing TRAIL-based cancer therapies.
Purpose of the Study:
- To investigate how cell-to-cell variability in TRAIL-induced apoptosis differs across cell types with varying sensitivities.
- To explore how drug combinations affect cell-to-cell variability in apoptosis timing and probability.
- To elucidate the mechanisms underlying the modulation of TRAIL-induced apoptosis by co-drugging.
Main Methods:
- Analysis of cell-to-cell variability in apoptosis induction by TRAIL in different tumor cell lines.
- Assessment of TRAIL sensitivity and cell death timing in clonal populations after treatment.
- Evaluation of drug combinations for their impact on apoptotic sensitivity and cell-to-cell variability.
Main Results:
- Fractional killing by TRAIL is a stable property of cell populations, with surviving cells regenerating parental sensitivity distributions.
- Drug combinations can effectively tune cell-to-cell variability in apoptosis timing and probability, enhancing overall apoptotic sensitivity.
- Co-drugging with TRAIL appears to reduce the threshold for mitochondrial outer membrane permeabilization, a key step in apoptosis.
Conclusions:
- Cell-to-cell variability in TRAIL response is a fundamental characteristic that can be modulated by therapeutic interventions.
- Combination therapies offer a strategy to overcome the limitations of single-agent TRAIL therapy by enhancing and standardizing apoptosis induction.
- Targeting the mitochondrial pathway through drug combinations may be a key mechanism for improving anti-cancer drug efficacy.
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