Direct observation of α-actinin tension and recruitment at focal adhesions during contact growth

Adherent cells interact with extracellular matrix via cell–substrate contacts at focal adhesions. The dynamic assembly and disassembly of focal adhesions enables cell attachment, migration and growth. While the influence of mechanical forces on the formation and growth of focal adhesions has been widely observed, the force loading on specific proteins at focal adhesion complex is not clear. By co-expressing force sensitive α-actinin FRET probes and fluorescence labeled paxillin in MDCK cells, we have simultaneously observed the time-dependent changes in tension in α-actinin and the dynamics of focal adhesion during cell migration. We show that increase in tension in α-actinin at the focal adhesion coincides with elongation of the adhesion in its growth phase. The enlargement of focal adhesion is through a force sensitive recruitment of α-actinin and paxillin to the adhesion sites. Changes in α-actinin tension and correlated relocation of α-actinin in an active adhesion also guide the growth direction of the adhesion. The results support the model that cytoskeletal tension is coupled to focal adhesion via the linking protein, α-actinin at the adhesion complex. Lysophosphatidic acid caused an immediate increase in α-actinin tension followed by drastic focal adhesion formation and elongation. Application of Rho-ROCK inhibitor, Y27632, resulted in reversible reduction in tension in α-actinin and disassociation of focal adhesion, suggesting the involvement of myosin-II mediated contractile force in the focal adhesion dynamics. These findings suggest that α-actinin not only serves as a physical linker between cytoskeleton and integrin, but also participates in force transmission at adhesion sites to facilitate adhesion?s growth.     

Lipid rafts control human melanoma cell migration by regulating focal adhesion disassembly

Tumor cell migration is a crucial step in the metastatic cascade, and interruption of this step is considered to be logically effective in preventing tumor metastasis. Lipid rafts, distinct liquid ordered plasma membrane microdomains, have been shown to influence cancer cell migration, but the underlying mechanisms are still not well understood. Here, we report that lipid rafts regulate the dynamics of actin cytoskeleton and focal adhesion in human melanoma cell migration. Disrupting the integrity of lipid rafts with methyl-β cyclodextrin enhances actin stress fiber formation and inhibits focal adhesion disassembly, accompanied with alterations in cell morphology. Furthermore, actin cytoskeleton, rather than microtubules, mediates the lipid raft-dependent focal adhesion disassembly by regulating the dephosphorylation of focal adhesion proteins and the internalization of β3 integrin. We also show that Src–RhoA–Rho kinase signaling pathway is responsible for lipid raft disruption-induced stress fiber formation. Taken together, these observations provide a new mechanism to further explain how lipid rafts regulate the migration of melanoma cell and suggest that lipid rafts may be novel and attractive targets for cancer therapy.     

Alpha-actinin interactions with syndecan-4 are integral to fibroblast–matrix adhesion and regulate cytoskeletal architecture

All cells of the musculoskeletal system possess transmembrane syndecan proteoglycans, notably syndecan-4. In fibroblasts it regulates integrin-mediated adhesion to the extracellular matrix. Syndecan-4 null mice have a complex wound repair phenotype while their fibroblasts have reduced focal adhesions and matrix contraction abilities. Signalling through syndecan-4 core protein to the actin cytoskeleton involves protein kinase Cα and Rho family G proteins but also direct interactions with α-actinin. The contribution of the latter interaction to cell–matrix adhesion is not defined but investigated here since manipulation of Rho GTPase and its downstream targets could not restore a wild type microfilament organisation to syndecan-4 null cells. Microarray and protein analysis revealed no significant alterations in mRNA or protein levels for actin- or α-actinin associated proteins when wild type and syndecan-4 knockout fibroblasts were compared. The binding site for syndecan-4 cytoplasmic domain was identified as spectrin repeat 4 of α-actinin while further experiments confirmed the importance of this interaction in stabilising cell–matrix junctions. However, α-actinin is also present in adherens junctions, these organelles not being disrupted in the absence of syndecan-4. Indeed, co-culture of wild type and knockout cells led to adherens junction-associated stress fibre formation in cells lacking syndecan-4, supporting the hypothesis that the proteoglycan regulates cell–matrix adhesion and its associated microfilament bundles at a post-translational level. These data provide an additional dimension to syndecan function related to tension at the cell–matrix interface, wound healing and potentially fibrosis.     

α9β1 Integrin in melanoma cells can signal different adhesion states for migration and anchorage

Cell surface integrins are the primary receptors for cell migration on extracellular matrix, and exist in several activation states regulated in part by ectodomain conformation. The α9 integrin subunit, which pairs only with β1, has specific roles in the immune system and may regulate cell migration. Melanoma cells express abundant α9β1 integrin, and its role in cell migration was assessed. Ligands derived from Tenascin-C and ADAM12 supported α9β1 integrin-mediated cell attachment and GTP-Rac dependent migration, but not focal adhesion formation. Manganese ions induced α9β1 integrin- and Rho kinase-dependent focal adhesion and stress fibre formation, suggesting that the activation status of α9β1 integrin was altered. The effect of manganese ions in promoting focal adhesion formation was reproduced by β1 integrin activating antibody. The α9β1 integrin translocated to focal adhesions, where active β1 integrin was also detected by conformation-specific antibodies. Focal adhesion assembly was commensurate with reduced cell migration. Endogenous α9β1 integrin-mediated adhesion was sensitive to the PP1 chemical inhibitor and an inhibitor of endosomal vesicle recycling, but not inhibitors of protein kinase C or the small GTPase Rho. Our results demonstrated that although α9β1 integrin can induce and localise to focal adhesions in a high activation state, its intermediate activity state normally supports cell adhesion consistent with migration.     

Tension is required but not sufficient for focal adhesion maturation without a stress fiber template

Focal adhesion composition and size are modulated in a myosin II-dependent maturation process that controls adhesion, migration, and matrix remodeling. As myosin II activity drives stress fiber assembly and enhanced tension at adhesions simultaneously, the extent to which adhesion maturation is driven by tension or altered actin architecture is unknown. We show that perturbations to formin and α-actinin 1 activity selectively inhibited stress fiber assembly at adhesions but retained a contractile lamella that generated large tension on adhesions. Despite relatively unperturbed adhesion dynamics and force transmission, impaired stress fiber assembly impeded focal adhesion compositional maturation and fibronectin remodeling. Finally, we show that compositional maturation of focal adhesions could occur even when myosin II-dependent cellular tension was reduced by 80%. We propose that stress fiber assembly at the adhesion site serves as a structural template that facilitates adhesion maturation over a wide range of tensions. This work identifies the essential role of lamellar actin architecture in adhesion maturation.     

HAMLET binding to α-actinin facilitates tumor cell detachment

Cell adhesion is tightly regulated by specific molecular interactions and detachment from the extracellular matrix modifies proliferation and survival. HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is a protein-lipid complex with tumoricidal activity that also triggers tumor cell detachment in vitro and in vivo, suggesting that molecular interactions defining detachment are perturbed in cancer cells. To identify such interactions, cell membrane extracts were used in Far-western blots and HAMLET was shown to bind α-actinins; major F-actin cross-linking proteins and focal adhesion constituents. Synthetic peptide mapping revealed that HAMLET binds to the N-terminal actin-binding domain as well as the integrin-binding domain of α-actinin-4. By co-immunoprecipitation of extracts from HAMLET-treated cancer cells, an interaction with α-actinin-1 and -4 was observed. Inhibition of α-actinin-1 and α-actinin-4 expression by siRNA transfection increased detachment, while α-actinin-4-GFP over-expression significantly delayed rounding up and detachment of tumor cells in response to HAMLET. In response to HAMLET, adherent tumor cells rounded up and detached, suggesting a loss of the actin cytoskeletal organization. These changes were accompanied by a reduction in β1 integrin staining and a decrease in FAK and ERK1/2 phosphorylation, consistent with a disruption of integrin-dependent cell adhesion signaling. Detachment per se did not increase cell death during the 22 hour experimental period, regardless of α-actinin-4 and α-actinin-1 expression levels but adherent cells with low α-actinin levels showed increased death in response to HAMLET. The results suggest that the interaction between HAMLET and α-actinins promotes tumor cell detachment. As α-actinins also associate with signaling molecules, cytoplasmic domains of transmembrane receptors and ion channels, additional α-actinin-dependent mechanisms are discussed.     

血管生成素相互作用蛋白质的筛选与鉴定

血管生成素（angiogenin, ANG）在肿瘤、神经退行性疾病和先天免疫过程中均发挥作用,但对其具体生理病理功能和作用机制的了解并不深入全面.蛋白质 蛋白质相互作用调控着细胞内的各个生物学过程,可以为目标蛋白质功能和机制的探索提供信息.本文利用酵母双杂交技术,分别从人心肌和肝cDNA文库中筛选了ANG的可能相互作用蛋白质.对筛选获得的20个候选蛋白质进行生物信息学分析,显示10个蛋白质含有EGF结构域;有5个蛋白质在KEGG 数据库已有记录,主要参与细胞黏附、通讯和迁移等过程.在以往的研究中,我们已经验证α 辅肌动蛋白2（α-actinin 2）、卵泡抑素（follistatin）、磷脂混杂酶1（phospholipid scramblase 1）和腓骨蛋白1（fibulin1）与ANG作用的真实性.本文的蛋白质沉降实验显示,ANG与腓骨蛋白2、3、4之间也存在相互作用.     

Distribution of the cadherin-catenin complex in normal human thyroid epithelium and a thyroid carcinoma cell line

E-cadherin is the major cell-cell adhesion molecule expressed by epithelial cells. Cadherins form a complex with three cytoplasmic proteins, α-, β-, and γ-catenin, and the interaction between them is crucial for anchoring the actin cytoskeleton to the intercellular adherens junctions. The invasive behavior of cancer cells has been attributed to a dysfunction of these molecules. In this study, we examined the distribution of the cadherin-catenin complex in a Chinese human thyroid cancer cell line, CGTH W-2, compared with that in normal human thyroid epithelial cells. In the normal cells, using immunofluorescence staining, E-cadherin and α-, β-, and γ-catenin were found to be localized at the intercellular junction and appeared as 135, 102, 90, and 80 kD proteins on Western blots. In CGTH W-2 cells, no E-cadherin and γ-catenin immunoreactivity was detected by immunofluorescence or Western blotting; α- and β-catenin were detected as 102 and 90 kD proteins on blots but gave a diffuse cytoplasmic immunofluorescence staining pattern in most cells, while β-catenin was also distributed throughout the cytoplasm in most cells but was found at the cell junction in some, where it colocalized with α-actinin. The present data indicate that the loss of cell adhesiveness in these cancer cells may be due to incomplete assembly of the cadherin-catenin complex at the cell junction. However, this defect did not affect the linkage of actin bundles to vinculin-enriched intercellular junctions. J. Cell. Biochem. 70:330–337, 1998. © 1998 Wiley-Liss, Inc.     

Effect of overexpression of β- and γ-actin isoforms on actin cytoskeleton organization and migration of human colon cancer cells

Actins are eukaryotic proteins, which are involved in diverse cellular functions including muscle contraction, cell motility, adhesion and maintenance of cell shape. Cytoplasmic actin isoforms β and γ are ubiquitously expressed and essential for cell functioning. However, their unique contributions are not very well understood. The aim of this study was to determine the effect of β- and γ-actin overexpression on the migration capacity and actin cytoskeleton organization of human colon adenocarcinoma BE cells. In cells overexpressing β- or γ-actin, distinct cytoskeletal actin rearrangements were observed under the laser scanning confocal microscope. Overexpressed actins localized at the submembranous region of the cell body, especially near to the leading edge and on the tips of pseudopodia. The cells transfected with plasmids containing cDNA for β- or γ-actin were characterized by increased migration and invasion capacities. However, the migration velocity was statistically significantly higher only in the case of γ-actin overexpressing cells. In conclusion, the increased level of β- or γ-actin leads to actin cytoskeletal remodeling followed by an increase in migration and invasion capacities of human colon BE cells. These data suggest that expression of both actin isoforms has an impact on cancer cell motility, with the subtle predominance of γ-actin, and may influence invasiveness of human colon cancer.     

α-Actinin Is Required for the Proper Assembly of Z-Disk/Focal-Adhesion-Like Structures and for Efficient Locomotion in Caenorhabditis elegans

The actin binding protein α-actinin is a major component of focal adhesions found in vertebrate cells and of focal-adhesion-like structures found in the body wall muscle of the nematode Caenorhabditis elegans. To study its in vivo function in this genetic model system, we isolated a strain carrying a deletion of the single C. elegans α-actinin gene. We assessed the cytological organization of other C. elegans focal adhesion proteins and the ultrastructure of the mutant. The mutant does not have normal dense bodies, as observed by electron microscopy; however, these dense-body-like structures still contain the focal adhesion proteins integrin, talin, and vinculin, as observed by immunofluorescence microscopy. Actin is found in normal-appearing I-bands, but with abnormal accumulations near muscle cell membranes. Although swimming in water appeared grossly normal, use of automated methods for tracking the locomotion of individual worms revealed a defect in bending. We propose that the reduced motility of α-actinin null is due to abnormal dense bodies that are less able to transmit the forces generated by actin/myosin interactions.     

Flow-induced focal adhesion remodeling mediated by local cytoskeletal stresses and reorganization

Cells respond to fluid shear stress through dynamic processes involving changes in actomyosin and other cytoskeletal stresses, remodeling of cell adhesions, and cytoskeleton reorganization. In this study we simultaneously measured focal adhesion dynamics and cytoskeletal stress and reorganization in MDCK cells under fluid shear stress. The measurements used co-expression of fluorescently labeled paxillin and force sensitive FRET probes of α-actinin. A shear stress of 0.74 dyn/cm² for 3 hours caused redistribution of cytoskeletal tension and significant focal adhesion remodeling. The fate of focal adhesions is determined by the stress state and stability of the linked actin stress fibers. In the interior of the cell, the mature focal adhesions disassembled within 35-40 min under flow and stress fibers disintegrated. Near the cell periphery, the focal adhesions anchoring the stress fibers perpendicular to the cell periphery disassembled, while focal adhesions associated with peripheral fibers sustained. The diminishing focal adhesions are coupled with local cytoskeletal stress release and actin stress fiber disassembly whereas sustaining peripheral focal adhesions are coupled with an increase in stress and enhancement of actin bundles. The results show that flow induced formation of peripheral actin bundles provides a favorable environment for focal adhesion remodeling along the cell periphery. Under such condition, new FAs were observed along the cell edge under flow. Our results suggest that the remodeling of FAs in epithelial cells under flow is orchestrated by actin cytoskeletal stress redistribution and structural reorganization.     

The PDZ-LIM protein CLP36 is required for actin stress fiber formation and focal adhesion assembly in BeWo cells

CLP36 belongs to the ALP subfamily of PDZ-LIM proteins and has a PDZ domain at its N-terminal and a LIM domain at its C-terminal. It has been shown that CLP36 is localized to stress fibers through interaction with α-actinin, but its function is still unclear. To investigate the role of CLP36 in stress fibers, we suppressed CLP36 expression in BeWo cells by RNAi and examined the phenotypic changes. CLP36-knockdown resulted in cell spreading and the loss of stress fibers and focal adhesions. These changes were reversed by addition of exogenous CLP36, but not by addition of mutant forms of CLP36 that lacked the PDZ or LIM domain. These findings indicate that CLP36 plays a critical role in stress fiber formation and the assembly of focal adhesions in BeWo cells. In addition, the PDZ and LIM domains are both essential for CLP36 to function.     

Stem Cell Factor Regulates the Melanocyte Cytoskeleton

Stem cell factor is a growth factor for normal human melanocytes, that acts through the tyrosine kinase receptor c-kit. We have previously demonstrated that stem cell factor increases melanocyte adhesion and migration on fibronectin, and regulates integrin protein expression. In this report, we have characterized the effect of stem cell factor on the organization of the actin cytoskeleton in human melanocytes attached to fibronectin, and have examined the effect of stem cell factor on the phosphorylation of the focal contact protein paxillin and on the expression of the focal contact proteins talin, paxillin, vinculin, and α-actinin. Paxillin is a vinculin-binding protein that is a substrate of focal adhesion kinase, a nonreceptor tyrosine kinase, and in its phosphorylated form is believed to stabilize focal contacts. We show that stem cell factor induces a rapid increase in actin stress fiber formation in melanocytes, which can be abrogated by genistein, a tyrosine kinase inhibitor, and that stem cell factor induces phosphorylation of paxillin on tyrosine residues. In contrast, stem cell factor did not regulate expression of any of the four focal contact proteins tested. These findings have implications for the models describing the mechanisms of action of stem cell factor on melanocyte adhesion and migration, and suggest that reorganization of the cytoskeleton is a primary effect of stem cell factor on human melanocytes.     

The TMEFF2 tumor suppressor modulates integrin expression,RhoA activation and migration of prostate cancer cells

Cell adhesion and migration play important roles in physiological and pathological states, including embryonic development and cancer invasion and metastasis. The type I transmembrane protein with epidermal growth factor and two follistatin motifs 2 (TMEFF2) is expressed mainly in brain and prostate and its expression is deregulated in prostate cancer. We have previously shown that TMEFF2 can function as a tumor suppressor by inhibiting cell migration and invasion of prostate cells. However, the molecular mechanisms involved in this inhibition are not clear. In this study we demonstrate that TMEFF2 affects cell adhesion and migration of prostate cancer cells and that this effect correlates with changes in integrin expression and RhoA activation. Deletion of a 13 basic-rich amino acid region in the cytoplasmic domain of TMEFF2 prevented these effects. Overexpression of TMEFF2 reduced cell attachment and migration on vitronectin and caused a concomitant decrease in RhoA activation, stress fiber formation and expression of αv, β1 and β3 integrin subunits. Conversely, TMEFF2 interference in 22Rv1 prostate cancer cells resulted in an increased integrin expression. Results obtained with a double TRAMP/TMEFF2 transgenic mouse also indicated that TMEFF2 expression reduced integrin expression in the mouse prostate. In summary, the data presented here indicate an important role of TMEFF2 in regulating cell adhesion and migration that involves integrin signaling and is mediated by its cytoplasmic domain.     

Expression of estrogen receptor β increases integrin α1 and integrin β1 levels and enhances adhesion of breast cancer cells

Estrogen effects on mammary gland development and differentiation are mediated by two receptors (ERα and ERβ). Estrogen‐bound ERα induces proliferation of mammary epithelial and cancer cells, while ERβ is important for maintenance of the differentiated epithelium and inhibits proliferation in different cell systems. In addition, the normal breast contains higher ERβ levels compared to the early stage breast cancers, suggesting that loss of ERβ could be important in cancer development. Analysis of ERβ?/? mice has consistently revealed reduced expression of cell adhesion proteins. As such, ERβ is a candidate modulator of epithelial homeostasis and metastasis. Consequently, the aim of this study was to analyze estrogenic effects on adhesion of breast cancer cells expressing ERα and ERβ. As ERβ is widely found in breast cancer but not in cell lines, we used ERα positive T47‐D and MCF‐7 human breast cancer cells to generate cells with inducible ERβ expression. Furthermore, the colon cancer cell lines SW480 and HT‐29 were also used. Integrin α1 mRNA and protein levels increased following ERβ expression. Integrin β1—the unique partner for integrin α1—increased only at the protein level. ERβ expression enhanced the formation of vinculin containing focal complexes and actin filaments, indicating a more adhesive potential. This was confirmed by adhesion assays where ERβ increased adhesion to different extracellular matrix proteins, mostly laminin. In addition, ERβ expression was associated to less cell migration. These results indicate that ERβ affects integrin expression and clustering and consequently modulates adhesion and migration of breast cancer cells. J. Cell. Physiol. 222:156–167, 2010. © 2009 Wiley‐Liss, Inc.     

Syndecan-4 and β1 integrin are regulated by electrical activity in skeletal muscle: Implications for cell adhesion

Syndecan-4 and integrins are involved in the cell migration and adhesion processes in several cell types. Syndecan-4, a transmembrane heparan sulfate proteoglycan, is associated to focal adhesions in adherent cells and has been described as a marker of satellite cells in skeletal muscle. In this tissue, β1 integrin forms heterodimers with α5 and α6 during myoblast differentiation and with α7 in adult muscle. Here, we show that the levels of these two cell surface membrane molecules are regulated by spontaneous electrical activity during the differentiation of rat primary myoblasts. Syndecan-4 and β1 integrin protein levels decrease after the inhibition of electrical activity using tetrodotoxin (TTX). Syndecan-4 also decreases substantially in denervated rat tibialis anterior muscle. Indirect immunofluorescence analysis shows that syndecan-4 and β1 integrin co-localize with vinculin, a molecular marker of costameres in skeletal muscle myofibers. Co-localization is lost in inactive myotubes adopting a diffuse pattern, suggesting that the costameric organization is disrupted in TTX-treated myotubes. Moreover, the inhibition of spontaneous electrical activity decreases myotube cell adhesion. In summary, this work shows that syndecan-4 and β1 integrin protein levels and their localization in costameric structures are regulated by electrical activity and suggests that this regulatory mechanism influences the adhesion properties of skeletal myotubes during differentiation.     

Up-regulated α-actin expression is associated with cell adhesion ability in 3-D cultured myocytes subjected to mechanical stimulation

This study was aimed to investigate the alteration of α-actin in three-dimensionally (3-D) cultured myocytes under cyclic tensile stress loading. Myocytes were collected from neonatal SD rat’s lateral pterygoid muscle for primary cell culture. The third-passage cells were implanted and 3-D cultured in poly lactic-co-glycolic acid (PLGA) scaffold, and then subjected to cyclic tensile stress (0.5 Hz, 2,000 μstrain) for 0, 2, 4, 8, 12, and 24 h through a four-point bending strain system. The α-actin mRNA was investigated by semi-quantitative RT–PCR. The α-actin protein expression was examined by immunofluorescent cytochemistry, laser confocal scanning microscopy (LCSM), and image analysis technology. The dynamic adhesion of myocytes to PLGA scaffolds was investigated by fluorescence microscope and the viability of the myocytes was measured by MTT assay. After mechanical loading, the α-actin mRNA increased at 2 h and then declined. The α-actin protein expression kept increased until peaked at 12 h, but declined at 24 h. The time course changing of α-actin protein expression parallelled with that of cell adhesion ability. It is concluded that α-actin expression is probably associated with cell adhesion ability in myocytes subjected to mechanical stimulation.     

Antagonistic regulation of cell migration by epidermal growth factor and glucocorticoid in human gastric carcinoma cells

Epidermal growth factor (EGF) induced the disruption and scattering of colonies of TMK-1, a cell line derived from a human gastric carcinoma. A stimulatory action of EGF on cell migration was also observed as determined by a wound assay. However, these actions of EGF were inhibited if the cells were pretreated with dexamethasone, a synthetic glucocorticoid. Dexamethasone increased cell adhesion to collagen type IV and laminin, but not to poly-L-lysine and fibronectin. In contrast, EGF did not affect cell adhesion to these extracellular matrices whether dexamethasone was present or not. Dexamethasone enhanced the protein levels of both α1 and β1 integrin subunits, and that of the α1 β1 heterodimer. Further, flow cytometric analysis revealed that dexamethasone increased the expression of β1 and α1 integrin subunits at the cell surface, whereas EGF increased expression of β1 and α2 subunits at the cell surface. Antibodies against α1 and β1 integrin subunits inhibited the increased cell adhesion seen in the presence of dexamethasone. An immunofluorescence study indicated that dexamethasone increased the formation of focal adhesions along the entire edges of cell colonies. In contrast, EGF led to the formation of focal adhesions preferentially at the cell front, and this EGF-induced preferential formation was not observed if the cells were pretreated with dexamethasone. These results suggest that glucocorticoid increased cell adhesion to the extracellular matrix via α1 β1 integrin, and therebyantagonized EGF-induced cell migration. J. Cell. Physiol. 176:127–137, 1998. © 1998 Wiley-Liss, Inc.     

Shear stress stimulates integrin β1 trafficking and increases directional migration of cancer cells via promoting deacetylation of microtubules

In egress routes of malignancy, cancer cells are constantly subjected to shear stress imposed by blood/lymph flow. Increasing evidence points toward the regulatory roles of shear stress in tumor cell adhesion and motility. Although it is known that integrin endocytic trafficking governs focal adhesion (FA) turnover and cell migration, the effect and biological consequences of low shear stress (LSS) on integrin trafficking remain unclear. Here, we identified the critical role of integrin β1 trafficking and caveolin-1 (Cav-1) mediated endocytosis in LSS-induced cell directional migration. LSS altered the distribution of integrin β1 in MDA-MB-231 cells and significantly promoted its internalization and recycling, which in turn facilitated FA turnover and directional cell migration. Furthermore, LSS induced cytoskeleton remodeling, which was required for internalization of integrin β1. LSS down-regulated the acetylation level of microtubules (MTs) via activating ROCK/HDAC6 pathway, resulting in elevation of MTs dynamics, Cav-1 motility, and Cav-1-dependent integrin β1 recycling. We also showed that high HDAC6 expression was a ROCK-dependent prognostic factor, which was correlated with poor outcomes in breast cancer patients. Taken together, these results defined a novel mechanism by which LSS enhanced integrin β1 trafficking via actin cytoskeleton remodeling and ROCK/HDAC6 mediated deacetylation of MTs, thereby promoting FAs turnover and directional cell migration.