p120catenin alteration in cancer and its role in tumour invasion

Inhibition of δ-catenin palmitoylation slows the progression of prostate cancer

Prostate cancer (PCa) is the second leading cause of death in males. It has been reported that δ-catenin expression is upregulated during the late stage of prostate cancer. Palmitoylation promotes protein transport to the cytomembrane and regulates protein localization and function. However, the effect of δ-catenin palmitoylation on the regulation of cancer remains unknown. In this study, we utilized prostate cancer cells overexpressing mutant δ-catenin (J6A cells) to induce a depalmitoylation phenotype and investigate its effect on prostate cancer. Our results indicated that depalmitoylation of δ-catenin not only reduced its membrane expression but also promoted its degradation in the cytoplasm, resulting in a decrease in the effect of EGFR and E-cadherin signaling. Consequently, depalmitoylation of δ-catenin reduced the proliferation and metastasis of prostate cancer cells. Our findings provide novel insights into potential therapeutic strategies for controlling the progression of prostate cancer through palmitoylation-based targeting of δ-catenin.

N-cadherin directs the collective Schwann cell migration required for nerve regeneration through Slit2/3-mediated contact inhibition of locomotion

Collective cell migration is fundamental for the development of organisms and in the adult for tissue regeneration and in pathological conditions such as cancer. Migration as a coherent group requires the maintenance of cell-cell interactions, while contact inhibition of locomotion (CIL), a local repulsive force, can propel the group forward. Here we show that the cell-cell interaction molecule, N-cadherin, regulates both adhesion and repulsion processes during Schwann cell (SC) collective migration, which is required for peripheral nerve regeneration. However, distinct from its role in cell-cell adhesion, the repulsion process is independent of N-cadherin trans-homodimerisation and the associated adherens junction complex. Rather, the extracellular domain of N-cadherin is required to present the repulsive Slit2/Slit3 signal at the cell surface. Inhibiting Slit2/Slit3 signalling inhibits CIL and subsequently collective SC migration, resulting in adherent, nonmigratory cell clusters. Moreover, analysis of ex vivo explants from mice following sciatic nerve injury showed that inhibition of Slit2 decreased SC collective migration and increased clustering of SCs within the nerve bridge. These findings provide insight into how opposing signals can mediate collective cell migration and how CIL pathways are promising targets for inhibiting pathological cell migration.

Expression of p120 - catenin in oral squamous cell carcinoma and apparently normal mucosa adjacent to oral squamous cell carcinoma

Background

An essential molecular occurrence in carcinogenesis that can lead to invasion and migration, predisposing cells to malignant transformation, involves alterations in cell adhesion molecules, such as p120 catenin. The destabilization of E-cadherin, caused by the loss or phosphorylation of p120 catenin (p120), regulates cadherin stability and turnover, impacting cell adhesiveness and migratory capacity. Consequently, p120 is associated with the invasiveness and progression of various human epithelial tumor types, including Oral Squamous Cell Carcinomas (OSCC). The present study aimed to assess and establish a correlation between the expression of p120 antibody in OSCC and Apparently Normal Mucosa Adjacent to OSCC (ANMAOSCC).

Material and Methods

The immunoexpression of p120 in 300 selected cases was categorized into two groups: OSCC (n = 150) and ANMAOSCC (n = 150). Two 4µm-thick tissue sections from the selected blocks were prepared. One section was stained with Hematoxylin and Eosin, while the other underwent immunohistochemical (IHC) staining using anti-p120 catenin antibody (clone No. EP66; Catalog No. PR062; PathnSitu, Wayne, PA, USA). The analysis of p120 immunoexpression included parameters such as intensity, percentage, and the location of staining.

Results

In OSCC, over 80% of cases expressed p120, with only 16% exhibiting loss of expression. In ANMAOSCC, all cells maintained p120 expression. In OSCC, p120 was predominantly localized to the membrane and cytoplasm in 76%, while in ANMAOSCC, over 90% showed membrane localization. Regarding positivity, only 19% of OSCC cases reported positivity in >50% of cells, compared to 64.7% in ANMAOSCC. The extent of staining in ANMAOSCC was observed up to the granular layer (45%) and corneal layer (19%).

Conclusions

The atypical staining pattern of p120 may indicate a loss of adhesion and could serve as a marker for identifying the malignant potential of ANMAOSCC and the aggressiveness of OSCC. Key words:Oral Squamous Cell Carcinoma, P120 Catenin, Cell Adhesion Molecules, Gene Expression Regulation.

Molecular Regulation and Oncogenic Functions of TSPAN8

Tetraspanins, a superfamily of small integral membrane proteins, are characterized by four transmembrane domains and conserved protein motifs that are configured into a unique molecular topology and structure in the plasma membrane. They act as key organizers of the plasma membrane, orchestrating the formation of specialized microdomains called "tetraspanin-enriched microdomains (TEMs)" or "tetraspanin nanodomains" that are essential for mediating diverse biological processes. TSPAN8 is one of the earliest identified tetraspanin members. It is known to interact with a wide range of molecular partners in different cellular contexts and regulate diverse molecular and cellular events at the plasma membrane, including cell adhesion, migration, invasion, signal transduction, and exosome biogenesis. The functions of cell-surface TSPAN8 are governed by ER targeting, modifications at the Golgi apparatus and dynamic trafficking. Intriguingly, limited evidence shows that TSPAN8 can translocate to the nucleus to act as a transcriptional regulator. The transcription of TSPAN8 is tightly regulated and restricted to defined cell lineages, where it can serve as a molecular marker of stem/progenitor cells in certain normal tissues as well as tumors. Importantly, the oncogenic roles of TSPAN8 in tumor development and cancer metastasis have gained prominence in recent decades. Here, we comprehensively review the current knowledge on the molecular characteristics and regulatory mechanisms defining TSPAN8 functions, and discuss the potential and significance of TSPAN8 as a biomarker and therapeutic target across various epithelial cancers.

PRMT-1 and p120-Catenin as EMT Mediators in Osimertinib Resistance in NSCLC

Osimertinib, an irreversible tyrosine kinase inhibitor, is a first-line therapy in EGFR-mutant NSCLC patients. Prolonged treatment with Osimertinib leads to resistance due to an acquired C797S mutation in the EGFR domain and other mechanisms, such as epithelial-mesenchymal transition (EMT). In this study, we investigated the role of PRMT-1 and p120-catenin in mediating Osimertinib resistance (OR) through EMT. These studies found upregulation of gene and protein expression of PRMT-1, p120-catenin and Kaiso factor. Knockdown of p120-catenin using siRNA increased OR efficacy by 45% as compared to cells treated with mock siRNA and OR. After 24 h of transfection, the percentage wound closure in cells transfected with p120-catenin siRNA was 26.2%. However, in mock siRNA-treated cells the wound closure was 7.4%, showing its involvement in EMT. We also found high levels of p120-catenin expressed in 30% of smokers as compared to 5.5% and 0% of non-smokers and quit-smokers (respectively) suggesting that smoking may influence p120-catenin expression in NSCLC patients. These results suggest that biomarkers such as PRMT-1 may mediate EMT by methylating Twist-1 and increasing p120-catenin expression, which causes transcriptional activation of genes associated with Kaiso factor to promote EMT in Osimertinib-resistant cells.

Role of the blood-spinal cord barrier: An adheren junction regulation mechanism that promotes chronic postsurgical pain

Chronic postsurgical pain (CPSP) is a serious postoperative complication with high incidence, and its pathogenesis involves neuroimmune interactions and the breakdown of the blood-spinal cord barrier (BSCB), the decreased level of adheren junction (AJ)-related proteins is an important cause of BSCB injury. Vascular endothelial-cadherin (VE-cadherin) and p120 catenin (p120) constitute the endothelial barrier adheren junction. The Src/p120/VE-cadherin pathway is involved in the regulation of the endothelial barrier function. However, the role of the BSCB-AJ regulatory mechanism in CPSP has not been reported. In this study, we established a skin/muscle incision and retraction (SMIR) model and evaluated the paw withdrawal threshold (PWT), the effects of an Src inhibitor and p120 knockdown on p-Src, p120 and VE-cadherin expression, as well as BSCB-AJ function in rat spinal cord were observed to explore the regulation of BSCB-AJ function by the p-Src/p120/VE-cadherin pathway in promoting SMIR-induced CPSP. The levels of p-Src, p120 and VE-cadherin in the spinal cord were detected by Western blot. Meanwhile, BSCB permeability test was used to detect the changes in BCSB function. Finally, the spatial and temporal localization of p120 in spinal cord was detected by immunofluorescence. Our findings indicated that p-Src/p120/VE-cadherin could induce BSCB-AJ dysfunction and promote the development of CPSP.

Substrate stiffness regulates the recurrent glioblastoma cell morphology and aggressiveness

Recurrent glioblastoma is highly aggressive with currently no specific treatment regime. Therefore, to identify novel therapeutic targets for recurrent GBM, we used a cellular model developed in our lab from commercially available cell line U87MG and patient-derived cultures that allows the comparison between radiation naïve (Parent) and recurrent GBM cells generated after parent cells are exposed to lethal dose of radiation. Total RNA-seq of parent and recurrent population revealed significant upregulation of cell-ECM interactions pathway in the recurrent population. These results led us to hypothesize that the physical microenvironment contributes to the aggressiveness of recurrent GBM. To verify this, we cultured parent and recurrent GBM cells on collagen-coated polyacrylamide gels mimicking the stiffness of normal brain (Young's modulus E = 0.5kPa) or tumorigenic brain (E = 10kPa) and tissue culture plastic dishes (E ∼ 1 GPa). We found that compared to parent cells, recurrent cells showed higher proliferation, invasion, migration, and resistance to EGFR inhibitor. Using orthotopic GBM mouse model and resection model, we demonstrate that recurrent cells cultured on 0.5kPa had higher in vivo tumorigenicity and recurrent disease progression than parent cells, whereas these differences were insignificant when parent and recurrent cells were cultured on plastic substrates. Furthermore, recurrent cells on 0.5kPa showed high expression of ECM proteins like Collagen, MMP2 and MMP9. These proteins were also significantly upregulated in recurrent patient biopsies. Additionally, the brain of mice injected with recurrent cells grown on 0.5kPa showed higher Young's moduli suggesting the ability of these cells to make the surrounding ECM stiffer. Total RNA-seq of parent and recurrent cells grown on plastic and 0.5kpa identified PLEKHA7 significantly upregulated specifically in recurrent cells grown on 0.5 kPa substrate. PLEKHA7 was also found to be high in recurrent GBM patient biopsies. Accordingly, PLEKHA7 knockdown reduced invasion and survival of recurrent GBM cells. Together, these data provide an in vitro model system that captures the observed in vivo and clinical behavior of recurrent GBM by mimicking mechanical microenvironment and identifies PLEKHA7 as a novel potential target for recurrent GBM.

Cadherins and the pathogenesis of epilepsy

Epilepsy is a nervous system disease caused by abnormal discharge of brain neurons, which is characterized by recurrent seizures. The factors that induce epilepsy include genetic and environmental factors. Genetic factors are important pathogenic factors of epilepsy, such as epilepsy caused by protocadherin-19 (PCDH-19) mutation, which is an X-linked genetic disease. It is more common in female heterozygotes, which are caused by mutations in the PCDH-19 gene. Epilepsy caused by environmental factors is mainly caused by brain injury, which is commonly caused by brain tumors, brain surgery, or trauma to the brain. In addition, the pathogenesis of epilepsy is closely related to abnormalities in some signaling pathways. The Wnt/β-catenin signaling pathway is considered a new target for the treatment of epilepsy. This review summarizes these factors inducing epilepsy and the research hypotheses regarding the pathogenesis of epilepsy. The focus of this review centers on cadherins and the pathogenesis of epilepsy. We analyzed the pathogenesis of epilepsy induced by N-cadherin and PCDH-19 in the cadherin family members. Finally, we expect that in the future, new breakthroughs will be made in the study of the pathogenesis and mechanism of epilepsy at the cellular and molecular levels.

Roles of CA125 in diagnosis, prediction, and oncogenesis of ovarian cancer

After it was discovered approximately 40 years ago, carbohydrate antigen 125 (CA125) became the most widely used and concerning biomarker in ovarian cancer screening. However, there is still controversy about its role in clinical practice. CA125 is not sufficiently reliable in diagnosis to screen for early-stage ovarian cancer. On the other hand, CA125 has been a valuable indicator for evaluating chemotherapeutic efficacy and prognosis. We still do not know much about its biological role, and several studies have indicated that this marker participates in the occurrence and development of ovarian cancer. Currently, an increasing number of scholars have begun to pay attention to CA125-targeted treatment strategies. In the interest of better design and development of anticancer therapies, a renewed and systematic understanding of the roles of CA125 in diagnosis, prediction, and tumorigenesis is warranted.

Proteomic Analysis Reveals a Role for RSK in p120-catenin Phosphorylation and Melanoma Cell-Cell Adhesion

The RAS/mitogen-activated protein kinase (MAPK) signaling pathway regulates various biological functions, including cell survival, proliferation and migration. This pathway is frequently deregulated in cancer, including melanoma, which is the most aggressive form of skin cancer. RSK (p90 ribosomal S6 kinase) is a MAPK-activated protein kinase required for melanoma growth and proliferation, but relatively little is known about its function and the nature of its cellular partners. In this study, we used a proximity-based labeling approach to identify RSK proximity partners in cells. We identified many potential RSK-interacting proteins, including p120ctn (p120-catenin), which is an essential component of adherens junction (AJ). We found that RSK phosphorylates p120ctn on Ser320, which appears to be constitutively phosphorylated in melanoma cells. We also found that RSK inhibition increases melanoma cell-cell adhesion, suggesting that constitutive RAS/MAPK signaling negatively regulates AJ integrity. Together, our results indicate that RSK plays an important role in the regulation of melanoma cell-cell adhesion.

P120 Catenin Isoforms Differentially Associate with Breast Cancer Invasion and Metastasis

Tumor metastasis is the endpoint of tumor progression and depends on the ability of tumor cells to locally invade tissue, transit through the bloodstream and ultimately to colonize secondary organs at distant sites. P120 catenin (p120) has been implicated as an important regulator of metastatic dissemination because of its roles in cell–cell junctional stability, cytoskeletal dynamics, growth and survival. However, conflicting roles for p120 in different tumor models and steps of metastasis have been reported, and the understanding of p120 functions is confounded by the differential expression of p120 isoforms, which differ in N-terminal length, tissue localization and, likely, function. Here, we used in silico exon expression analyses, in vitro invasion assays and both RT-PCR and immunofluorescence of human tumors. We show that alternative exon usage favors expression of short isoform p120-3 in 1098 breast tumors and correlates with poor prognosis. P120-3 is upregulated at the invasive front of breast cancer cells migrating as collective groups in vitro. Furthermore, we demonstrate in histological sections of 54 human breast cancer patients that p120-3 expression is maintained throughout the metastatic cascade, whereas p120-1 is differentially expressed and diminished during invasion and in metastases. These data suggest specific regulation and functions of p120-3 in breast cancer invasion and metastasis.

Microtubules: Evolving roles and critical cellular interactions

Microtubules are cytoskeletal elements known as drivers of directed cell migration, vesicle and organelle trafficking, and mitosis. In this review, we discuss new research in the lens that has shed light into further roles for stable microtubules in the process of development and morphogenesis. In the lens, as well as other systems, distinct roles for characteristically dynamic microtubules and stabilized populations are coming to light. Understanding the mechanisms of microtubule stabilization and the associated microtubule post-translational modifications is an evolving field of study. Appropriate cellular homeostasis relies on not only one cytoskeletal element, but also rather an interaction between cytoskeletal proteins as well as other cellular regulators. Microtubules are key integrators with actin and intermediate filaments, as well as cell–cell junctional proteins and other cellular regulators including myosin and RhoGTPases to maintain this balance.

Impact statement

The role of microtubules in cellular functioning is constantly expanding. In this review, we examine new and exciting fields of discovery for microtubule’s involvement in morphogenesis, highlight our evolving understanding of differential roles for stabilized versus dynamic subpopulations, and further understanding of microtubules as a cellular integrator.

p120ctn-Mediated Organ Patterning Precedes and Determines Pancreatic Progenitor Fate

The mechanism of how organ shape emerges and specifies cell fate is not understood. Pancreatic duct and endocrine lineages arise in a spatially distinct domain from the acinar lineage. Whether these lineages are pre-determined or settle once these niches have been established remains unknown. Here, we reconcile these two apparently opposing models, demonstrating that pancreatic progenitors re-localize to establish the niche that will determine their ultimate fate. We identify a p120ctn-regulated mechanism for coordination of organ architecture and cellular fate mediated by differential E-cadherin based cell sorting. Reduced p120ctn expression is necessary and sufficient to re-localize a subset of progenitors to the peripheral tip domain, where they acquire an acinar fate. The same mechanism is used re-iteratively during endocrine specification, where it balances the choice between the alpha and beta cell fates. In conclusion, organ patterning is regulated by p120ctn-mediated cellular positioning, which precedes and determines pancreatic progenitor fate.

MUC16 impacts tumor proliferation and migration through cytoplasmic translocation of P120-catenin in epithelial ovarian cancer cells: an original research

Background

Epithelial ovarian cancer (EOC) remains one of the most lethal gynecologic cancers, and its pathogenetic mechanism remains unclear. Here we show that MUC16 promotes the translocation of p120-catenin (p120ctn) to the cytoplasm and consequently activates ras homolog (Rho) GTPases RhoA/Cdc42 activation to modulate the proliferation and migration abilities of EOC cells.

Methods

We collect 94 ovarian cancer (OC) patients’ tissue samples to constitute tissue microarray (TMA) and analyze the MUC16 and p120ctn expression levels. Lentivirus transfection is used to overexpress cytoplasmic tail domain (CTD) of MUC16 and CRISPR/Cas9 genome-editing system is firstly used to knock out MUC16 in EOC cells. The proliferation or migration ability of cells is analyzed by MTS or migration assay.

Results

We find that MUC16 and p120ctn are aberrantly overexpressed in 94 clinical OC samples compared with benign ovarian tumors (BOT). MUC16 is a critical inducer of the proliferation and migration of EOC cells and the CTD of MUC16 plays an important role during this process. In addition, we reveal the relationship between MUC16 and p120ctn, which has not previously been studied. We show that MUC16 promotes the translocation of p120ctn to the cytoplasm and consequently activates Rho GTPases to modulate the proliferation and migration abilities of EOC cells. The cell proliferation and migration abilities induced by MUC16 are mediated by p120ctn through RhoA/Cdc42 activation.

Conclusions

The highly expressed MUC16 promotes the translocation of p120ctn to the cytoplasm, where it activates RhoA/Cdc42 to modulate the proliferation and migration abilities of EOC cells. These findings may provide new targets for the treatment of EOC.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5371-4) contains supplementary material, which is available to authorized users.

Signaling by Small GTPases at Cell-Cell Junctions: Protein Interactions Building Control and Networks

A number of interesting reports highlight the intricate network of signaling proteins that coordinate formation and maintenance of cell-cell contacts. We have much yet to learn about how the in vitro binding data is translated into protein association inside the cells and whether such interaction modulates the signaling properties of the protein. What emerges from recent studies is the importance to carefully consider small GTPase activation in the context of where its activation occurs, which upstream regulators are involved in the activation/inactivation cycle and the GTPase interacting partners that determine the intracellular niche and extent of signaling. Data discussed here unravel unparalleled cooperation and coordination of functions among GTPases and their regulators in supporting strong adhesion between cells.

Divergent roles of p120-catenin isoforms linked to altered cell viability, proliferation, and invasiveness in carcinogen-induced rat skin tumors

The heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) targets multiple organs for tumorigenesis in the rat, including the colon and the skin. PhIP-induced skin tumors were subjected to mutation screening, which identified genetic changes in Hras (7/40, 17.5%) and Tp53 (2/40, 5%), but not in Ctnnb1, a commonly mutated gene in PhIP-induced colon tumors. Despite the absence of Ctnnb1 mutations, β-catenin was overexpressed in nuclear and plasma membrane fractions from PhIP-induced skin tumors, coinciding with loss of p120-catenin from the plasma membrane, and the appearance of multiple p120-catenin-associated bands in the nuclear extracts. Real-time RT-PCR revealed that p120-catenin isoforms 1 and 4 were upregulated in PhIP-induced skin tumors, whereas p120-catenin isoform 3 was expressed uniformly, compared with adjacent normal-looking tissue. In human epidermoid carcinoma and colon cancer cells, transient transfection of p120-catenin isoform 1A enhanced the viability and cell invasion index, whereas transient transfection of p120-catenin isoform 4A increased cell viability and cell proliferation. Knockdown of p120-catenin revealed a corresponding reduction in the expression of β-catenin and a transcriptionally regulated target, Ccnd1/Cyclin D1. Co-immunoprecipitation experiments identified associations of β-catenin with p120-catenin isoforms in PhIP-induced skin tumors and human cancer cell lines. The results are discussed in the context of therapeutic strategies that might target different p120-catenin isoforms, providing an avenue to circumvent constitutively active β-catenin arising via distinct mechanisms in skin and colon cancer.

p120-catenin in canonical Wnt signaling

Canonical Wnt signaling controls β-catenin protein stabilization, its translocation to the nucleus and the activation of β-catenin/Tcf-4-dependent transcription. In this review, we revise and discuss the recent results describing actions of p120-catenin in different phases of this pathway. More specifically, we comment its involvement in four different steps: (i) the very early activation of CK1ɛ, essential for Dvl-2 binding to the Wnt receptor complex; (ii) the internalization of GSK3 and Axin into multivesicular bodies, necessary for a complete stabilization of β-catenin; (iii) the activation of Rac1 small GTPase, required for β-catenin translocation to the nucleus; and (iv) the release of the inhibitory action caused by Kaiso transcriptional repressor. We integrate these new results with the previously known action of other elements in this pathway, giving a particular relevance to the responses of the Wnt pathway not required for β-catenin stabilization but for β-catenin transcriptional activity. Moreover, we discuss the possible future implications, suggesting that the two cellular compartments where β-catenin is localized, thus, the adherens junction complex and the Wnt signalosome, are more physically connected that previously thought.

The Src non-receptor tyrosine kinase paradigm: New insights into mammalian Sertoli cell biology

Src kinases are non-receptor tyrosine kinases that phosphorylate diverse substrates, which control processes such as cell proliferation, differentiation and survival; cell adhesion; and cell motility. c-Src, the prototypical member of this protein family, is widely expressed by several organs that include the testis. In the seminiferous epithelium of the adult rat testis, c-Src is highest at the tubule lumen during the release of mature spermatids. Other studies show that testosterone regulates spermatid adhesion to Sertoli cells via c-Src, indicating Src phosphorylates key substrates that prompt the disassembly of Sertoli cell-spermatid junctions. A more recent in vitro study reveals that c-Src participates in the internalization of proteins that constitute the blood-testis barrier, which is present between Sertoli cells, suggesting a similar mechanism of junction disassembly is at play during spermiation. In this review, we discuss recent findings on c-Src, with an emphasis on its role in spermatogenesis in the mammalian testis.

Epithelial-to-Mesenchymal Plasticity Harnesses Endocytic Circuitries

The ability of cells to alter their phenotypic and morphological characteristics, known as cellular plasticity, is critical in normal embryonic development and adult tissue repair and contributes to the pathogenesis of diseases, such as organ fibrosis and cancer. The epithelial-to-mesenchymal transition (EMT) is a type of cellular plasticity. This transition involves genetic and epigenetic changes as well as alterations in protein expression and post-translational modifications. These changes result in reduced cell-cell adhesion, enhanced cell adhesion to the extracellular matrix, and altered organization of the cytoskeleton and of cell polarity. Among these modifications, loss of cell polarity represents the nearly invariable, distinguishing feature of EMT that frequently precedes the other traits or might even occur in their absence. EMT transforms cell morphology and physiology, and hence cell identity, from one typical of cells that form a tight barrier, like epithelial and endothelial cells, to one characterized by a highly motile mesenchymal phenotype. Time-resolved proteomic and phosphoproteomic analyses of cells undergoing EMT recently identified thousands of changes in proteins involved in many cellular processes, including cell proliferation and motility, DNA repair, and - unexpectedly - membrane trafficking (1). These results have highlighted a picture of great complexity. First, the EMT transition is not an all-or-none response but rather a gradual process that develops over time. Second, EMT events are highly dynamic and frequently reversible, involving both cell-autonomous and non-autonomous mechanisms. The net results is that EMT generates populations of mixed cells, with partial or full phenotypes, possibly accounting (at least in part) for the physiological as well as pathological cellular heterogeneity of some tissues. Endocytic circuitries have emerged as complex connectivity infrastructures for numerous cellular networks required for the execution of different biological processes, with a primary role in the control of polarized functions. Thus, they may be relevant for controlling EMT or certain aspects of it. Here, by discussing a few paradigmatic cases, we will outline how endocytosis may be harnessed by the EMT process to promote dynamic changes in cellular identity, and to increase cellular flexibility and adaptation to micro-environmental cues, ultimately impacting on physiological and pathological processes, first and foremost cancer progression.