Cell Polarity Research Articles

Dinámica de los receptores de quimioquinas en la membrana celular

Chemokines are chemotactic cytokines that control the migratory patterns and positioning of many cells, including immune cells. Although chemokines were initially considered to be important mediators of acute inflammation, we now know that this complex system of ligands and receptors is essential for the generation of primary and secondary adaptive cellular and humoral immune responses. In addition, they also trigger other biological responses ranging from cell polarization or movement or the prevention of HIV-1 infection. Chemokine-mediated cell activation was believed to be due to the binding of a monomeric chemokine to its monomeric receptor. However, the biology of these mediators is more complex than initially anticipated, as several studies indicate that chemokines dimerize. In addition, the use of new advanced optical imaging techniques have made possible to determine that the receptors also form dimers, homo- and heterodimers, as well as higher order oligomers at the cell surface. These are very dynamic and plastic structures/conformations, influenced by the presence of ligands, the co-expression of other receptors and proteins, the lipid composition of the cell membrane or the environment where cells perform their function. Keywords: Chemokines; Chemokine receptors; Receptor conformation; Molecular dynamics; Signaling

Blocking M2-Like Macrophage Polarization Using Decoy Oligodeoxynucleotide-Based Gene Therapy Prevents Immune Evasion for Pancreatic Cancer Treatment.

M2-like macrophages exhibit immunosuppressive activity and promote pancreatic cancer progression. Reactive oxygen species (ROS) affect macrophage polarization; however, the mechanism remains unclear. This study aimed to elucidate the underlying molecular basis and design a gene therapy to inhibit M2-like polarization. Microarray analysis and immunofluorescence staining were performed in M1-like and M2-like macrophages to ascertain the expression of CYBB, a major intracellular ROS source. Coculture assay and syngeneic orthotopic pancreatic cancer mice models were used to study the mechanism of M2-like skewing. Decoy oligodeoxynucleotides (ODNs) were designed to manipulate CYBB transcription to inhibit M2-like polarization and control tumor growth. Lipopolysaccharide treatment polarized U937 cells to M1-like macrophages in which CYBB expression was increased. In contrast, coculture with PANC-1 cells induced M2-like polarization in U937 cells with CYBB downregulation. High CD204 M2-like expression in combination with low CYBB expression was associated with the worst prognosis in patients with pancreatic cancer. STAT6 and HDAC2 in U937 cells were activated by cancer cell-derived IL4 after coculture and then bound to the CYBB promoter to repress CYBB expression, resulting in M2-like polarization. Diphenyleneiodonium, 8λ³-iodatricyclo[7.4.0.02,⁷]trideca-1(13),2,4,6,9,11-hexaen-8-ylium chloride that inhibits ROS production could block this action. Knockdown of STAT6 and HDAC2 also inhibited M2-like polarization and maintained the M1-like phenotype of U937 cells after coculture. Decoy ODNs interrupting the binding of STAT6 to the CYBB promoter counteracted M2-like polarization and tumor growth and triggered antitumor immunity in vivo. Gene therapy using STAT6-CYBB decoy ODNs can inhibit M2-like polarization, representing a potential therapeutic tool for pancreatic cancer.

Fructose 1,6-bisphosphatase as a promising target of anticancer treatment

Fructose 1,6-bisphosphatase (FBP) is a regulatory enzyme of gluconeogenesis that also influences in a non-catalytic manner – via protein-protein interactions – cell cycle-dependent events, mitochondria biogenesis and polarization, synaptic plasticity and even cancer progression. FBP reduces glycolytic capacity of cells via blocking HIF-1α transcriptional activity and modulating NF-κB action, and influences oxidative metabolism by binding to c-MYC. Because FBP limits the energy-producing potential of cells and because a reduction of FBP amounts is observed in cancer cells, FBP is considered to be an anti-oncogenic protein. This is supported by the observation that cancer cells overexpress aldolase A (ALDOA), a pro-oncogenic protein that can bind to FBP and potentially block its anti-oncogenic activity. Interestingly, only the muscle isozyme of FBP (FBP2) interacts strongly with ALDOA, whereas the binding of the liver isozyme (FBP1) to ALDOA is more than an order of magnitude weaker.Here, we briefly review the most important evidence supporting the anti-oncogenic function of FBP and discuss what structural properties of the two FBP isozymes allow FBP2, rather than FBP1, to exert more flexible anticancer functions.

Deletion within ameloblastin multitargeting domain reduces its interaction with artificial cell membrane

In human, mutations in the gene encoding the enamel matrix protein ameloblastin (Ambn) have been identified in cases of amelogenesis imperfecta. In mouse models, perturbations in the Ambn gene have caused loss of enamel and dramatic disruptions in enamel-making ameloblast cell function. Critical roles for Ambn in ameloblast cell signaling and polarization as well as adhesion to the nascent enamel matrix have been supported. Recentely, we have identified a multitargeting domain (MTD) in Ambn that interacts with cell membrane, with the majority enamel matrix protein amelogenin, and with itself. This domain includes an amphipathic helix (AH) motif that directly interacts with cell membrane. In this study, we analyzed the sequence of the MTD for evolutionary conservation and found high conservation among mammals within the MTD and particularly within the AH motif. We computationally predicted that the AH motif lost its hydrophobic moment upon deleting hydrophobic but not hydrophilic residues from the motif. Furthermore, we rationally designed peptides that encompassed the Ambn MTD and contained deletions of largely hydrophobic or hydrophilic stretches of residues. To assess their AH-forming and membrane-binding abilities, we combined those peptides with synthetic phospholipid membrane vesicles and performed circular dichroism, membrane leakage, and vesicle clearance measurements. Circular dichroism showed retention of α-helix formation in all peptides except the one with the largest deletion of eleven amino acids including seven that were hydrophobic. This same peptide variant failed to cause leakage or clearance of synthetic membranes, while smaller deletions yielded intermediate membrane interaction as measured by leakage and clearance assays. Our data revealed that deletion of key hydrophobic residues from the AH leads to the most dramatic loss of Ambn–membrane interaction. Pinpointing roles of residues within the MTD has important implications for the multifunctionality of Ambn.

SARS-CoV-2-derived protein Orf9b enhances MARK2 activity via interaction with the autoinhibitory KA1 domain.

Microtubule affinity-regulating kinase 2 (MARK2) is a Ser/Thr protein kinase that regulates cell polarity and immune responses. Here, we report that Orf9b, one of the accessory proteins encoded in the SARS-CoV-2 genome, increases MARK2 activity via interaction with the autoinhibitory KAI domain. We found that co-expression of Orf9b enhances the kinase activity of MARK2 in HEK293 cells. Orf9b does not bind to or enhance the activity of the mutant form of MARK2 lacking the KA1 domain. Orf9b lowers inhibitory phosphorylation of MARK2 at T595 while mutation experiments indicate that this site is dispensable for Orf9b-mediated enhancement of MARK2 activity. Our results suggest that Orf9b enhances MARK2 activity by binding the autoinhibitory KA1 domain, which closely interacts with the kinase domain.

Linkage between Fuz and Gpr161 genes regulates sonic hedgehog signaling during mouse neural tube development.

Sonic hedgehog (Shh) signaling regulates embryonic morphogenesis utilizing the primary cilium, the cell's antenna, which acts as a signaling hub. Fuz, an effector of planar cell polarity signaling, regulates Shh signaling by facilitating cilia formation, and the G protein-coupled receptor 161 (Gpr161) is a negative regulator of Shh signaling. The range of phenotypic malformations observed in mice bearing mutations in either of the genes encoding these proteins is similar; however, their functional relationship has not been previously explored. This study identified the genetic and biochemical linkage between Fuz and Gpr161 in mouse neural tube development. Fuz was found to be genetically epistatic to Gpr161 with respect to regulation of Shh signaling in mouse neural tube development. The Fuz protein biochemically interacts with Gpr161, and Fuz regulates Gpr161-mediated ciliary localization, a process that might utilize β-arrestin 2. Our study characterizes a previously unappreciated Gpr161-Fuz axis that regulates Shh signaling during mouse neural tube development.

Optimization of culture conditions to generate vascularized multi-lineage liver organoids with structural complexity and functionality

Hepatic organoids (HOs), primarily composed of hepatobiliary cells, do not represent the pathogenesis of liver diseases due to the lack of non-parenchymal cells. Multi-lineage liver organoids (mLOs) containing various cell types found in the liver offer a promising in vitro disease model. However, their structural complexity remains challenging to achieve due to the difficulty in optimizing culture conditions that meet the growth need of all component cell types. Here, we demonstrate that cystic HOs generated from hPSCs can be expanded long-term and serve as a continuous source for generating complex mLOs. Assembling cystic HOs with hPSC-derived endothelial and hepatic stellate cell-like cells under conventional HO culture conditions failed to support the development of multiple cell types within mLOs, resulting in biased differentiation towards specific cell types. In contrast, modulating the cAMP/Wnt/Hippo signaling pathways with small molecules during assembly and differentiation phases efficiently generate mLOs containing both hepatic parenchymal and non-parenchymal cells. These mLOs exhibited structural complexity and functional maturity, including vascular network formation between parenchymal lobular structures, cell polarity for bile secretion, and the capacity to respond to fibrotic stimuli. Our study underscores the importance of modulating signaling pathways to enhance mLO structural complexity for applications in modeling liver pathologies.

Collagen prolyl 4-hydroxylase subunit α member-induced head and neck squamous cell carcinoma aggressiveness is antagonized by LLGL2 via reduced expression of occludin.

There are three isoforms of human collagen prolyl 4-hydroxylases (C-P4Hs), each of which has been reported to play an important role in regulating the progression of a variety of human cancers. By analyzing TGCA datasets on human head and neck squamous cell carcinoma (HNSC), we find that a higher expression of all three C-P4HAs (the α subunit of C-P4Hs) is a superior prognostic indicator than a higher expression of two or a single C-P4HA. Unexpectedly, some patients with higher levels of three C-P4HAs survive longer than patients whose tumors have lower expression of C-P4HAs. Therefore, there may be molecule(s) that can negate the deleterious effects of overexpressing C-P4HAs during cancer progression. By constructing a functional protein interaction network of C-P4HAs and analyzing molecules whose expressions are correlated significantly with that of C-P4HAs, we identify scribble cell polarity complex component 2 (LLGL2) as a factor that antagonizes the effects of overexpressed C-P4HAs on HNSC. Silencing of LLGL2 in the human oral squamous cell line Cal-27 upregulates the expression of occludin and increases cancer cell invasion and migration. In contrast, knocking down C-P4HA alone inhibits cell migration and invasion. Furthermore, simultaneously downregulating three C-P4HAs has more pronounced effects on inhibiting cell migration and invasion. Accordingly, high LLGL2 expression is also a marker indicating improved prognosis in patients with HNSC. These results suggest that the interplay between LLGL2 and C-P4HAs may be targeted to mitigate HNSC tumorigenesis and progression.

NFATc1 in CD4+ T cells and CD11c+ dendritic cells drives TH2-mediated eosinophilic inflammation in allergic asthma

BackgroundAsthma, a chronic lung disease, is a significant public health problem worldwide. It is marked by increased Th2 response resulting in eosinophil accumulation. The pathophysiology of asthma involves various cell types, including epithelial cells, dendritic cells (DCs), innate lymphoid cells (ILCs), B cells, and effector cells. Nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), a critical transcription factor for immune regulation, is known for its role in T cells and, more recently, in myeloid cells. However, the specific contributions of NFATc1 in T cells and DCs in the context of asthma are not well understood. ObjectiveExplore NFATc1’s role in T cells and dendritic cells in modulating Th2 immune responses within the pathophysiology of allergic asthma. MethodsMice lacking Nfatc1 in CD4+T cells or CD11c+ dendritic cells, were induced with asthma using house dust mite (HDM), enabling investigation into NFATc1's role in both cell types in experimental allergic asthma. Additionally, the study examined NFATc1 expression in these cells and its correlation with blood eosinophil levels in an adult asthma cohort. ResultsIn HDM-induced asthma model, we found that Nfatc1 deficiency either in CD4+ T cells or CD11c+ dendritic cells resulted in reduced Th2-driven eosinophilic inflammation, immunoglobulin E (IgE) levels, and mast cell presence in the lung of asthmatic mice. Nfatc1's absence in CD4+ T cells directly hampered Th2 cell polarization and functionality, whereas in CD11c+ dendritic cells, it affected DC differentiation and maturation, thereby weakening T cell priming, proliferation and subsequent Th2 differentiation. Correspondingly, translational research indicated significant correlations between CD4+NFATc1+ and CD11c+NFATc1+ cell populations and eosinophil levels in asthmatic patients, but not in healthy controls. ConclusionNFATc1 in T cells and dendritic cells modulate Th2-mediated eosinophilic inflammation in allergic asthma, which offering insights into asthma pathogenesis and identifying NFATc1 as a potential target for therapeutic intervention.

Early Cell Lineage Formation in Mammals: Complexity, Species Diversity, and Susceptibility to Disruptions Impacting Embryo Viability.

The emergence of the earliest cell lineages in mammalian embryos is a complex process that utilizes an extensive network of chromatin regulators, transcription factors, cell polarity regulators, and cellular signaling pathways. These factors and pathways operate over a protracted period of time as embryos cleave, undergo compaction, and form blastocysts. The first cell fate specification event separates the pluripotent inner cell mass from the trophectoderm lineage. The second event separates pluripotent epiblast from hypoblast. This review summarizes over 50 years of study of these early lineage forming events, addressing the complexity of the network of interacting molecules, cellular functions and pathways that drive them, interspecies differences, and aspects of these mechanisms that likely underlie their high susceptibility to disruption by numerous environmental factors that can compromise embryo viability, such as maternal health and diet, environmental toxins, and other stressors.

Prognostic value of PLEKHA4 and its correlation with tumor-infiltrating immune cells in breast cancer: a comprehensive study based on bioinformatics and clinical analysis validation.

Pleckstrin homology containing family A, number 4 (PLEKHA4) plays a role in a number of biological processes in human cells, including cell polarization, growth, and proliferation. However, the relationship between PLEKHA4 expression and survival in breast cancer (BC) remains unclear. The aim of this study is to investigate the potential of PLEKHA4 as a prognostic indicator in BC. We obtained gene expression profiles of BC and normal tissues from the Tumor Immune Estimation Resource (TIMER), UALCAN web. Immunohistochemistry (IHC) staining was performed to investigate the protein expression and prognostic value of PLEKHA4 in BC patients. The prognostic value was analyzed using Kaplan-Meier curve analysis and Cox regression analysis in R software after downloading The Cancer Genome Atlas (TCGA) databases. The correlations between PLEKHA4 and tumor immune infiltrates were investigated via gene set variation analysis (GSVA). Signaling pathways related to PLEKHA4 expression were identified by the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Both bioinformatics and IHC results showed that PLEKHA4 was expressed at low levels in BC tissues compared with the adjacent tissues. Furthermore, the expression of PLEKHA4 was negatively correlated with ages (χ2=6.394, P=0.01), molecular subtype (χ2=15.606, P=0.001), lymph node metastasis (χ2=13.753, P=0.004), tumor-node-metastasis (TNM) stage (χ2=22.616, P<0.001). Kaplan-Meier curves implicated low expression of PLEKHA4 was associated with worse survival of BC patients [hazard ratio (HR) =0.46, P=0.01]. Cox regression models showed that low PLEKHA4 expression could be an independent risk factor for BC (HR =0.911, P=0.006). The results of gene set enrichment analysis (GSEA) showed that cell cycle, Notch signaling pathway, nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathway, and Rho GTPases were highly enriched in the low PLEKHA4 expression group, as identified by GO and KEGG. Additionally, in BC, PLEKHA4 expression displayed a positive correlation with the infiltration of natural killer (NK) cells (P<0.001), CD8+ T cells (P<0.001), B cells (P<0.001), neutrophils (P<0.001), and dendritic cells (DCs) (P<0.001). The findings indicate that PLEKHA4 is an independent prognostic biomarker associated with key signaling pathways and immune infiltration in BC. Targeting PLEKHA4 may contribute to improving immunotherapy for BC.

Fluorescence lifetime imaging: A novel approach to simultaneous visualizing lipid droplets and endoplasmic reticulum polarity in live cells and fatty liver

Cellular polarity plays an indispensable role in both physiological functions and the progression of diseases, with organelles demonstrating specific polarities that are integral to their roles. The advent of a single fluorescent probe capable of concurrently and selectively visualizing two distinct organelles through distinct fluorescence emission spectra has emerged as a powerful approach for investigating their interactions within cellular mechanisms. However, the use of changes in dual fluorescence lifetimes to monitor polarity changes in two organelles has rarely been employed, despite its potential benefits for more accurate detection of subtle changes in organelle polarity. Herein, two polarity-sensitive probes (ER-LDs-1 and ER-LDs-2) were developed. ER-LDs-2 exhibited high sensitivity to polarity alterations in both lipid droplets (LDs) and endoplasmic reticulum (ER) under various physiological and pathological conditions, including ferroptosis and endoplasmic reticulum stress, as demonstrated by distinct changes in fluorescence lifetime. ER-LDs-2 enables the monitoring of polarity changes in mouse and human normal and fatty liver tissues by fluorescence lifetime imaging. Collectively, this study presents innovative tools that hold great potential for advancing our understanding of cellular organelle polarity dynamics and the progression of associated diseases.

Blockade of Crk eliminates Yki/YAP-activated tumors via JNK-mediated apoptosis in Drosophila

Selective elimination of cancer cells without causing deleterious effects on normal cells is an ideal anti-cancer strategy. Here, using Drosophila cancer model, we performed an in vivo RNAi screen for anti-cancer targets that selectively eliminate tumors without affecting normal tissue growth. In Drosophila imaginal epithelium, clones of cells expressing oncogenic Ras with simultaneous mutations in the cell polarity gene scribble (RasV12/scrib−/−) develop into malignant tumors. We found that knockdown of Crk, the Drosophila ortholog of human CRK (CT10 regulatory kinase) and CRKL (Crk-like) adapter proteins, significantly suppresses growth of RasV12/scrib−/− tumors by inducing c-Jun N-terminal kinase (JNK)-mediated apoptosis, while it does not affect growth of normal epithelium. Mechanistically, Crk inhibition blocks Yorkie (Yki)/YAP activity by impairing F-actin accumulation, an upstream event of Yki/YAP activation in tumors. Inhibition of Yki/YAP in tumors causes intracellular JNK signaling to be used for apoptosis induction. Given that molecules and signaling pathways identified in Drosophila are highly conserved and activated in human cancers, our findings would provide a novel, to the best of our knowledge, anti-cancer strategy against YAP-activated cancers.

Inactivation of JNK signalling results in polarity loss and cell senescence of Sertoli cell.

As major somatic cells in the testis, Sertoli cell development is precisely regulated by numerous factors, and aberrant development of these cells is associated with male reproductive diseases. JNK signalling is evolutionarily conserved and involved in multiple critical biological processes. Here, we found that the double knockout of Jnk1 and Jnk2 resulted in aberrant localisation of Sertoli cells at early developmental stages, with most Sertoli cells being lost at later stages. Further studies revealed that the inactivation of JNK signalling caused polarity loss in Sertoli cells. In vitro-cultured Jnk1/2-DKO Sertoli cells exhibited a senescence-associated phenotype. Mechanistic studies demonstrate that JNK signalling is likely involved in establishing Sertoli cell polarity by regulating the expression of TGF-β2, mediated by c-Jun. The senescence of Sertoli cells in JNKs-deficient mice is caused by aberrant proteolysis of P27KIP1, mediated by c-Myc. This study demonstrates the role of JNK signalling in Sertoli cell development and functional maintenance, which may also represent an aetiology of male infertility in humans.

Molecular mechanisms of polarized transport to the apical plasma membrane.

Cell polarity is essential for cellular function. Directional transport within a cell is called polarized transport, and it plays an important role in cell polarity. In this review, we will introduce the molecular mechanisms of polarized transport, particularly apical transport, and its physiological importance.

Membrane-Targeting Amphiphilic Honokiol Derivatives Containing an Oxazole Moiety as Potential Antibacterials against Methicillin-Resistant Staphylococcus aureus.

Infections with methicillin-resistant Staphylococcus aureus (MRSA) are becoming increasingly serious, making the development of novel antimicrobials urgent. Here, we synthesized some amphiphilic honokiol derivatives bearing an oxazole moiety and investigated their antibacterial and hemolytic activities. Bioactivity evaluation showed that E17 possessed significant in vitro antibacterial activity against S. aureus and MRSA, along with low hemolytic activity. Moreover, E17 exhibited rapid bactericidal properties and was not susceptible to resistance. Mechanistic studies indicated that E17 interacts with phosphatidylglycerol and cardiolipin of bacterial cell membranes, leading to changes in cell membrane permeability and polarization, increased intracellular ROS, and leakage of DNA and proteins, thus accelerating bacterial death. Transcriptome analysis further demonstrated that E17 has membrane-targeting effects, affecting the expression of genes related to cell membranes and ABC transporter proteins. Notably, in vivo activity showed that E17 has prominent anti-MRSA efficacy, comparable to vancomycin, and is expected to be a new anti-MRSA drug candidate.

Curdlan-Mediated Syngeneic RNAi against NF-κB in Glial Cells Protects Cerebral Vessels in the TBI Mouse Model.

Traumatic brain injury (TBI) activates the NF-κB pathway in microglia and astrocytes, which secrete pro-inflammatory cytokines that disrupt the blood-brain barrier (BBB). Curdlan derivatives are promising carriers for the delivery of siRNA drugs. Herein, we evaluated the glial cell specificity, siRNA delivery efficiency, and the subsequent phenotypic regulation of glial cells by the Curdlan derivatives in the TBI mouse model. Our in vitro and in vivo studies confirmed that the (1) pAVC4 or CuMAN polymer encapsulating siRNA were internalized by astrocytes and microglia in a receptor-dependent manner; (2) systemic administration of the pAVC4 or CuMAN polymer encapsulating siRNA resulted in significant gene silencing efficiency, altered the phenotypic polarization of glial cells, and regulated the secretion of inflammatory cytokines; (3) this lessened neuroinflammation, ameliorated BBB destruction, and improved vascular recovery. These data suggested that pAVC4 and CuMAN polymers are promising RNA delivery vehicles that can efficiently deliver siRNA to the target cells.

Paracrine FGF1 signaling directs pituitary architecture and size

Organ architecture is established during development through intricate cell-cell communication mechanisms, yet the specific signals mediating these communications often remain elusive. Here, we used the anterior pituitary gland that harbors different interdigitated hormone-secreting homotypic cell networks to dissect cell-cell communication mechanisms operating during late development. We show that blocking differentiation of corticotrope cells leads to pituitary hypoplasia with a major effect on somatotrope cells that directly contact corticotropes. Gene knockout of the corticotrope-restricted transcription factor Tpit results in fewer somatotropes, with less secretory granules and a loss of cell polarity, resulting in systemic growth retardation. Single-cell transcriptomic analyses identified FGF1 as a corticotrope-specific Tpit dosage-dependent target gene responsible for these phenotypes. Consistently, genetic ablation of FGF1 in mice phenocopies pituitary hypoplasia and growth impairment observed in Tpit-deficient mice. These findings reveal FGF1 produced by the corticotrope cell network as an essential paracrine signaling molecule participating in pituitary architecture and size.

Antagonistic action of Siah2 and Pard3/JamC to promote germinal zone exit of differentiated cerebellar granule neurons by modulating Ntn1 signaling via Dcc.

Exiting a germinal zone (GZ) initiates a cascade of events that promote neuronal maturation and circuit assembly. Developing neurons and their progenitors must interpret various niche signals-such as morphogens, guidance molecules, extracellular matrix components, and adhesive cues-to navigate this region. How differentiating neurons integrate and adapt to multiple cell-extrinsic niche cues with their cell-intrinsic machinery in exiting a GZ is unknown. We establish cooperation between cell polarity-regulated adhesion and Netrin-1 (Ntn-1) signaling comprises a coincidence detection circuit repelling maturing neurons from their GZ. In this circuit, the Partitioning defective 3 (Pard3) polarity protein and Junctional adhesion molecule-C (JamC) adhesion protein promote, while the Seven in absentia 2 (Siah2) ubiquitin ligase inhibits, Deleted in colorectal cancer (Dcc) receptor surface recruitment to gate differentiation linked repulsion to GZ Ntn-1. These results demonstrate cell polarity as a central integrator of adhesive- and guidance cues cooperating to spur GZ exit.

Protrusion force and cell-cell adhesion play a critical role in collective tumor cluster migration.

While collective migration is shown to enhance invasive and metastatic potential in cancer, the mechanisms driving this behavior and regulating tumor migration plasticity remain poorly understood. This study provides a mechanistic framework explaining the emergence of different modes of collective migration under hypoxia-induced secretome. We focus on the interplay between cellular protrusion force and cell-cell adhesion using collectively migrating three-dimensional microtumors as models with well-defined microenvironment. Large microtumors show directional migration due to intrinsic hypoxia, while small microtumors exhibit radial migration in response to hypoxic secretome. Here, we developed the minimal multi-scale microtumor model (MSMM) to elucidate underlying mechanisms. We identified distinct migration modes within specific regions of protrusion force and cell-cell adhesion parameter space. We show that sufficient cellular protrusion force is crucial for both, radial and directional collective microtumor migration. Radial migration emerges when sufficient cellular protrusion force is generated, driving neighboring cells to move collectively in diverse directions. Within migrating tumors, strong cell-cell adhesion enhances the alignment of cell polarity, breaking the symmetric angular distribution of protrusion forces, and leading to directional microtumor migration. The integrated results from the experimental and computational models provide fundamental insights into collective migration in response to different microenvironment stimuli.