Bryanjantzen4801

Optogenetics uses light to manipulate protein localization or activity from subcellular to supra-cellular level with unprecedented spatiotemporal resolution. We used it to control the activity of the Cdc42 Rho GTPase, a major regulator of actin polymerization and cell polarity. In this chapter, we describe how to trigger and guide cell migration using optogenetics as a way to mimic EMT in an artificial yet highly controllable fashion.The epithelial-mesenchymal transition (EMT) and the corresponding reverse process, mesenchymal-epithelial transition (MET), are dynamic and reversible cellular programs orchestrated by many changes at both biochemical and morphological levels. A recent surge in identifying the molecular mechanisms underlying EMT/MET has led to the development of various mathematical models that have contributed to our improved understanding of dynamics at single-cell and population levels (a) multi-stability-how many phenotypes can cells attain during an EMT/MET?, (b) reversibility/irreversibility-what time and/or concentration of an EMT inducer marks the "tipping point" when cells induced to undergo EMT cannot revert?, (c) symmetry in EMT/MET-do cells take the same path when reverting as they took during the induction of EMT?, and (d) non-cell autonomous mechanisms-how does a cell undergoing EMT alter the tendency of its neighbors to undergo EMT? These dynamical traits may facilitate a heterogenous response within a cell population undergoing EMT/MET. Here, we present a few examples of designing different mathematical models that can contribute to decoding EMT/MET dynamics.Metastasis results from the ability of cancer cells to grow and to spread beyond the primary tumor to distant organs. Epithelial-to-Mesenchymal Transition (EMT), a fundamental developmental process, is reactivated in cancer cells, and causes epithelial properties to evolve into mesenchymal and invasive ones. EMT changes cellular characteristics between two distinct states, yet, the process is not binary but rather reflects a broad spectrum of partial EMT states in which cells exhibit various degrees of intermediate epithelial and mesenchymal phenotypes. EMT is a complex multistep process that involves cellular reprogramming through numerous signaling pathways, alterations in gene expression, and changes in chromatin morphology. Therefore, expression of key proteins, including cadherins, occludin, or vimentin must be precisely regulated. A comprehensive understanding of how changes in nuclear organization, at the level of single genes clusters, correlates with these processes during formation of metastatic cells is still missing and yet may help personalized prognosis and treatment in the clinic. Here, we describe methods to correlate physiological and molecular states of cells undergoing an EMT process with chromatin rearrangements observed via FISH labeling of specific domains.Epithelial-Mesenchymal Transition (EMT) and its reciprocal Mesenchymal-Epithelial Transition (MET) occur naturally as a cycling process during embryonic and foetal development. The capacity of such iterative cycles to drive cell fate and cellular and molecular behaviour in physiology or pathology remains unclear. We describe here a protocol to induce successive cycles of EMT/MET in an untransformed human mammary epithelial cell line (MCF10A) as well as the necessary controls for cycle validation.The critical role of metabolism in facilitating cancer cell growth and survival has been demonstrated by a combination of methods including, but not limited to, genomic sequencing, transcriptomic and proteomic analyses, measurements of radio-labelled substrate flux and the high throughput measurement of oxidative metabolism in unlabelled live cells using the Seahorse Extracellular Flux (XF) technology. These studies have revealed that tumour cells exhibit a dynamic metabolic plasticity, using numerous pathways including both glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) to support cell proliferation, energy production and the synthesis of biomass. These advanced technologies have also demonstrated metabolic differences between cancer cell types, between molecular subtypes within cancers and between cell states. This has been exemplified by examining the transitions of cancer cells between epithelial and mesenchymal phenotypes, referred to as epithelial-mesenchymal plasticity (EMP). A growingin turn can be correlated to EMP phenotypes. Normalisation of bioenergetic studies should be considered with respect to cell number, and to potential differences in mitochondrial mass, itself being an important bioenergetics endpoint.Metastasis and chemoresistance, the most lethal features of cancer progression, are strongly associated with a form of cellular plasticity known as the epithelial-to-mesenchymal transition (EMT). Carcinoma cells undergoing EMT lose their epithelial morphology and become more mobile, allowing them to invade and migrate more efficiently. This shift is also associated with a change in vulnerability to chemotherapeutic agents. Durvalumab manufacturer Importantly, EMT does not involve a single mechanism, but rather encompasses a spectrum of phenotypes with differing degrees of epithelial and mesenchymal characteristics. These hybrid/partial epithelial-mesenchymal states are associated with other important aspects of tumor biology, such as distinct modes of cellular invasion and drug resistance, illustrating the need to further characterize this phenomenon in tumor cells. Although simple in theory, the identification of tumor cells that have undergone EMT in vivo has proven difficult due to their high similarity to other mesenchymal cells that populate tumor stroma, such as cancer-associated fibroblasts. This protocol describes two methods for isolating epithelial and EMT cancer cell populations from primary murine tumors and cultured cancer cells to identify different EMT subtypes. These populations can then be used for several applications, including, but not limited to, functional studies of motility or invasion, gene expression analysis (RNA sequencing and RT-qPCR), DNA sequencing, epigenetic analysis, tumor subtyping, western blotting, immunohistochemistry, etc. Finally, we describe a flow cytometry-based approach to identify and study tumors cells that are undergoing partial EMT.