The role of hyaluronan in tumour neovascularization (review)

Self-assembled hyaluronic acid nanoparticles for the topical treatment of inflammatory skin diseases: Beyond drug carriers

Inflammatory skin diseases represent a significant health concern, affecting approximately 20-25% of the global population. These conditions not only reduce an individual's quality of life but also impose a huge burden on both humanity and society. However, addressing these challenges is hindered by their chronic nature, insufficient therapeutic effectiveness, and the propensity for recurrence and adverse side effects. Hyaluronic acid (HA) has emerged as a potential solution to these barriers, owing to its excellent attributes such as biocompatibility, non-toxicity, and targeted drug delivery. However, its practical application has been limited because endogenous hyaluronidase (HYAL) rapidly degrades HA in inflamed skin thus reducing its ability to penetrate deep into the skin. Interestingly, recent research has expanded the role of self-assembled HA-nanoparticles (HA-NPs) beyond drug carriers; they are resistant to HYAL, thereby enabling deep skin penetration, and possess inherent anti-inflammatory properties. Moreover, these abilities can be fine-tuned depending on the conditions during particle synthesis. Additionally, their role as a drug delivery system holds potential for use as a multi-target drug or hybrid drug. In conclusion, this review aims to specifically introduce and highlight the emerging potential of HA-NPs as a topical treatment for inflammatory skin conditions.

Nanomedicine Strategies for Targeting Tumor Stroma

The tumor stroma, or the microenvironment surrounding solid tumors, can significantly impact the effectiveness of cancer therapies. The tumor microenvironment is characterized by high interstitial pressure, a consequence of leaky vasculature, and dense stroma created by excessive deposition of various macromolecules such as collagen, fibronectin, and hyaluronic acid (HA). In addition, non-cancerous cells such as cancer-associated fibroblasts (CAFs) and the extracellular matrix (ECM) itself can promote tumor growth. In recent years, there has been increased interest in combining standard cancer treatments with stromal-targeting strategies or stromal modulators to improve therapeutic outcomes. Furthermore, the use of nanomedicine, which can improve the delivery and retention of drugs in the tumor, has been proposed to target the stroma. This review focuses on how different stromal components contribute to tumor progression and impede chemotherapeutic delivery. Additionally, this review highlights recent advancements in nanomedicine-based stromal modulation and discusses potential future directions for developing more effective stroma-targeted cancer therapies.

Aptamer/doxorubicin-conjugated nanoparticles target membranous CEMIP2 in colorectal cancer

The objectives were to identify the functional domains of a potential oncoprotein, cell migration inducing hyaluronidase 2 (CEMIP2), evaluate its expression levels and roles in colorectal cancer (CRC), and develop an aptamer-based nanoparticle for targeted therapy. Data mining on TCGA identified that CEMIP2 might play oncogenic roles in CRC. In a local cohort, CEMIP2 mRNA levels significantly stepwise increase in CRC patients with higher stages, and high CEMIP2 confers worse disease-free survival. In addition, CEMIP2 mRNA levels significantly correlated to hyaluronan levels in sera from CRC patients. Deletion mapping identified that CEMIP2 containing G8 and PANDER-like domains preserved hyaluronidase activity and oncogenic roles, including cell proliferation, anchorage-independent cell growth, cell migration and invasion, and human umbilical vein endothelial cell (HUVEC) tube formation in CRC-derived cells. A customized monoclonal mouse anti-human CEMIP2 antibody probing the PANDER-like domain (anti-289307) counteracted CEMIP2-mediated carcinogenesis in vitro. Cell-SELEX pinpointed an aptamer, aptCEMIP2(101), specifically interacted with the full-length CEMIP2, potentially involving its 3D structure. Treatments with aptCEMIP2(101) significantly reduced CEMIP2-mediated tumorigenesis in vitro. Mesoporous silica nanoparticles (MSN) carrying atpCEMIP2(101) and Dox were fabricated. Dox@MSN, MSN-aptCEMIP2(101), and Dox@MSN-aptCEMIP2(101) significantly suppressed tumorigenesis in vitro compared to the Mock, while Dox@MSN-aptCEMIP2(101) showed substantially higher effects compared to Dox@MSN and MSN-aptCEMIP2(101) in CRC-derived cells. Our study identified a novel oncogene and developed an effective aptamer-based targeted therapeutic strategy.

Enzymatically Crosslinked Collagen as a Versatile Matrix for In Vitro and In Vivo Co-Engineering of Blood and Lymphatic Vasculature

Adequate vascularization is required for the successful translation of many in vitro engineered tissues. This study presents a novel collagen derivative that harbors multiple recognition peptides for orthogonal enzymatic crosslinking based on sortase A (SrtA) and Factor XIII (FXIII). SrtA-mediated crosslinking enables the rapid co-engineering of human blood and lymphatic microcapillaries and mesoscale capillaries in bulk hydrogels. Whereas tuning of gel stiffness determines the extent of neovascularization, the relative number of blood and lymphatic capillaries recapitulates the ratio of blood and lymphatic endothelial cells originally seeded into the hydrogel. Bioengineered capillaries readily form luminal structures and exhibit typical maturation markers both in vitro and in vivo. The secondary crosslinking enzyme Factor XIII is used for in situ tethering of the VEGF mimetic QK peptide to collagen. This approach supports the formation of blood and lymphatic capillaries in the absence of exogenous VEGF. Orthogonal enzymatic crosslinking is further used to bioengineer hydrogels with spatially defined polymer compositions with pro- and anti-angiogenic properties. Finally, macroporous scaffolds based on secondary crosslinking of microgels enable vascularization independent from supporting fibroblasts. Overall, this work demonstrates for the first time the co-engineering of mature micro- and meso-sized blood and lymphatic capillaries using a highly versatile collagen derivative.

Extracellular Matrix-Derived Biophysical Cues Mediate Interstitial Flow-Induced Sprouting Angiogenesis

Sprouting angiogenesis is orchestrated by an intricate balance of biochemical and mechanical cues in the local tissue microenvironment. Interstitial flow has been established as a potent regulator of angiogenesis. Similarly, extracellular matrix (ECM) physical properties, such as stiffness and microarchitecture, have also emerged as important mediators of angiogenesis. However, the interplay between interstitial flow and ECM physical properties in the initiation and control of angiogenesis is poorly understood. Using a three-dimensional (3D) microfluidic tissue analogue of angiogenic sprouting with defined interstitial flow superimposed over ECM with well-characterized physical properties, we found that the addition of hyaluronan (HA) to collagen-based matrices significantly enhances sprouting induced by interstitial flow compared to responses in collagen-only hydrogels. We confirmed that both the stiffness and matrix pore size of collagen-only hydrogels were increased by the addition of HA. Interestingly, interstitial flow-potentiated sprouting responses in collagen/HA matrices were not affected when functionally blocking the HA receptor CD44. In contrast, enzymatic depletion of HA in collagen/HA matrices with hyaluronidase (HAdase) resulted in decreased stiffness, pore size, and interstitial flow-mediated sprouting to the levels observed in collagen-only matrices. Taken together, these results suggest that HA enhances interstitial flow-mediated angiogenic sprouting through its alterations to collagen ECM stiffness and pore size.

Tachyplesin I and its derivatives: A pharmaco-chemical perspective on their antimicrobial and antitumor potential

INTRODUCTION

Increasing evidence suggests that intratumor microbiota are an intrinsic component in the tumor microenvironment across multiple cancer types, and that there is a close relationship between microbiota and tumor progression. Therefore, how to address the interaction between bacteria and malignances has become a growing concern. Tachyplesin I (TPI), a peptide with dual antimicrobial and antitumor effects, holds great promise as a therapeutic alternative for the aforementioned diseases, with the advantage of broad-spectrum activities, quick killing efficacy, and a low tendency to induce resistance.

AREAS COVERED

This review comprehensively summarizes the pharmacological mechanisms of TPI with an emphasis on its antimicrobial and antitumor potential. Furthermore, it presents advances in TPI derivatives and gives a perspective on their future development. The article is based on literature searches using PubMed and SciFinder to retrieve the most up-to-date information of TPI.

EXPERT OPINION

Bacterial infections and cancer both pose a serious threat to health due to their symbiotic interactions and drug resistance. TPI is anticipated to be a novel agent to control pathogenic bacteria and various tumors through multiple mechanisms of action. Indeed, the continuous advancements in chemical modification and innovative applications of TPI give hope for future improvements in therapeutic efficacy.

Profound Effects of Dexamethasone on the Immunological State, Synthesis and Secretion Capacity of Human Testicular Peritubular Cells

The functions of human testicular peritubular cells (HTPCs), forming a small compartment located between the seminiferous epithelium and the interstitial areas of the testis, are not fully known but go beyond intratesticular sperm transport and include immunological roles. The expression of the glucocorticoid receptor (GR) indicates that they may be regulated by glucocorticoids (GCs). Herein, we studied the consequences of the GC dexamethasone (Dex) in cultured HTPCs, which serves as a unique window into the human testis. We examined changes in cytokines, mainly by qPCR and ELISA. A holistic mass-spectrometry-based proteome analysis of cellular and secreted proteins was also performed. Dex, used in a therapeutic concentration, decreased the transcript level of proinflammatory cytokines, e.g., IL6, IL8 and MCP1. An siRNA-mediated knockdown of GR reduced the actions on IL6. Changes in IL6 were confirmed by ELISA measurements. Of note, Dex also lowered GR levels. The proteomic results revealed strong responses after 24 h (31 significantly altered cellular proteins) and more pronounced ones after 72 h of Dex exposure (30 less abundant and 42 more abundant cellular proteins). Dex also altered the composition of the secretome (33 proteins decreased, 13 increased) after 72 h. Among the regulated proteins were extracellular matrix (ECM) and basement membrane components (e.g., FBLN2, COL1A2 and COL3A1), as well as PTX3 and StAR. These results pinpoint novel, profound effects of Dex in HTPCs. If transferrable to the human testis, changes specifically in ECM and the immunological state of the testis may occur in men upon treatment with Dex for medical reasons.

Nanotechnology for Targeted Therapy of Atherosclerosis

Atherosclerosis is the major cause of heart attack and stroke that are the leading causes of death in the world. Nanomedicine is a powerful tool that can be engineered to target atherosclerotic plaques for therapeutic and diagnosis purposes. In this review, advances in designing nanoparticles with therapeutic effects on atherosclerotic plaques known as atheroprotective nanomedicine have been summarized to stimulate further development and future translation.

Mechanisms underlying unidirectional laminar shear stress-mediated Nrf2 activation in endothelial cells: Amplification of low shear stress signaling by primary cilia

Endothelial cells are sensitive to mechanical stress and respond differently to oscillatory flow versus unidirectional flow. This review highlights the mechanisms by which a wide range of unidirectional laminar shear stress induces activation of the redox sensitive antioxidant transcription factor nuclear factor-E2-related factor 2 (Nrf2) in cultured endothelial cells. We propose that fibroblast growth factor-2 (FGF-2), brain-derived neurotrophic factor (BDNF) and 15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) are potential Nrf2 activators induced by laminar shear stress. Shear stress-dependent secretion of FGF-2 and its receptor-mediated signaling is tightly controlled, requiring neutrophil elastase released by shear stress, αvβ3 integrin and the cell surface glycocalyx. We speculate that primary cilia respond to low laminar shear stress (<10 dyn/cm2), resulting in secretion of insulin-like growth factor 1 (IGF-1), which facilitates αvβ3 integrin-dependent FGF-2 secretion. Shear stress induces generation of heparan-binding epidermal growth factor-like growth factor (HB-EGF), which contributes to FGF-2 secretion and gene expression. Furthermore, HB-EGF signaling modulates FGF-2-mediated NADPH oxidase 1 activation that favors casein kinase 2 (CK2)-mediated phosphorylation/activation of Nrf2 associated with caveolin 1 in caveolae. Higher shear stress (>15 dyn/cm2) induces vesicular exocytosis of BDNF from endothelial cells, and we propose that BDNF via the p75NTR receptor could induce CK2-mediated Nrf2 activation. Unidirectional laminar shear stress upregulates gene expression of FGF-2 and BDNF and generation of 15d-PGJ2, which cooperate in sustaining Nrf2 activation to protect endothelial cells against oxidative damage.

Anti-angiogenesis Function of Ononin via Suppressing the MEK/Erk Signaling Pathway

Angiogenesis is a complicated pathological process and plays an important role in modulating tumor development. Flavonoids, sharing the basic functional group with estrogen, have been utilized as chemopreventive agents to inhibit endothelial cell angiogenesis and also suppress tumor cell proliferation. Ononin, also referred to as formononetin-7-O-β-d-glucoside, is one of the bioactive chemicals found within many functional food or plants. The anticancer functions of ononin have been reported both in vitro and in vivo. However, the anti-angiogenetic properties of ononin have not been reported. The possible efficacies of ononin against angiogenesis was verified in cultured endothelial cells. Ononin suppressed vascular endothelial growth factor (VEGF)-induced HUVEC migration, invasion. and tube formation activity after 48 h. The apoptosis rate and specific markers, i.e., Bax/Bc-2 ratio, cleaved caspase 3/9 (Cl-caspase 3/9), and cytochrome c (Cyto c), were enhanced in the ononin-treated group. On the other hand, the protein expressions levels of hypoxia-inducible factor 1α (HIF-1α), mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK), and vascular endothelial growth factor receptor 2 (VEGFR2) were restricted after ononin treatment for 2 days in VEGF-pretreated endothelial cells. In summary, ononin acts as a candidate for angiogenetic-related disease prevention and treatment.

Hyaluronan control of the primary vascular barrier during early mouse pregnancy is mediated by uterine NK cells

Successful implantation is associated with a unique spatial pattern of vascular remodeling, characterized by profound peripheral neovascularization surrounding a periembryo avascular niche. We hypothesized that hyaluronan controls the formation of this distinctive vascular pattern encompassing the embryo. This hypothesis was evaluated by genetic modification of hyaluronan metabolism, specifically targeted to embryonic trophoblast cells. The outcome of altered hyaluronan deposition on uterine vascular remodeling and postimplantation development were analyzed by MRI, detailed histological examinations, and RNA sequencing of uterine NK cells. Our experiments revealed that disruption of hyaluronan synthesis, as well as its increased cleavage at the embryonic niche, impaired implantation by induction of decidual vascular permeability, defective vascular sinus folds formation, breach of the maternal-embryo barrier, elevated MMP-9 expression, and interrupted uterine NK cell recruitment and function. Conversely, enhanced deposition of hyaluronan resulted in the expansion of the maternal-embryo barrier and increased diffusion distance, leading to compromised implantation. The deposition of hyaluronan at the embryonic niche is regulated by progesterone-progesterone receptor signaling. These results demonstrate a pivotal role for hyaluronan in successful pregnancy by fine-tuning the periembryo avascular niche and maternal vascular morphogenesis.

Hyaluronan fine-tunes the periembryo avascular niche and maternal vascular morphogenesis during implantation.

Polymer microcapsules and microbeads as cell carriers for in vivo biomedical applications

Polymer microcarriers are being extensively explored as cell delivery vehicles in cell-based therapies and hybrid tissue and organ engineering. Spherical microcarriers are of particular interest due to easy fabrication and injectability. They include microbeads, composed of a porous matrix, and microcapsules, where matrix core is additionally covered with a semipermeable membrane. Microcarriers provide cell containment at implantation site and protect the cells from host immunoresponse, degradation and shear stress. Immobilized cells may be genetically altered to release a specific therapeutic product directly at the target site, eliminating side effects of systemic therapies. Cell microcarriers need to fulfil a number of extremely high standards regarding their biocompatibility, cytocompatibility, immunoisolating capacity, transport, mechanical and chemical properties. To obtain cell microcarriers of specified parameters, a wide variety of polymers, both natural and synthetic, and immobilization methods can be applied. Yet so far, only a few approaches based on cell-laden microcarriers have reached clinical trials. The main issue that still impedes progress of these systems towards clinical application is limited cell survival in vivo. Herein, we review polymer biomaterials and methods used for fabrication of cell microcarriers for in vivo biomedical applications. We describe their key limitations and modifications aiming at improvement of microcarrier in vivo performance. We also present the main applications of polymer cell microcarriers in regenerative medicine, pancreatic islet and hepatocyte transplantation and in the treatment of cancer. Lastly, we outline the main challenges in cell microimmobilization for biomedical purposes, the strategies to overcome these issues and potential future improvements in this area.

Hyaluronic Acid Nanoparticles as Nanomedicine for Treatment of Inflammatory Diseases

Owing to their unique biological functions, hyaluronic acid (HA) and its derivatives have been explored extensively for biomedical applications such as tissue engineering, drug delivery, and molecular imaging. In particular, self-assembled HA nanoparticles (HA-NPs) have been used widely as target-specific and long-acting nanocarriers for the delivery of a wide range of therapeutic or diagnostic agents. Recently, it has been demonstrated that empty HA-NPs without bearing any therapeutic agent can be used therapeutically for the treatment of inflammatory diseases via modulating inflammatory responses. In this review, we aim to provide an overview of the significant achievements in this field and highlight the potential of HA-NPs for the treatment of inflammatory diseases.

The role of CD44 in pathological angiogenesis

Angiogenesis is required for normal development and occurs as a pathological step in a variety of disease settings, such as cancer, ocular diseases, and ischemia. Recent studies have revealed the role of CD44, a widely expressed cell surface adhesion molecule, in promoting pathological angiogenesis and the development of its associated diseases through its regulation of diverse function of endothelial cells, such as proliferation, migration, adhesion, invasion, and communication with the microenvironment. Conversely, the absence of CD44 expression or inhibition of its function impairs pathological angiogenesis and disease progression. Here, we summarize the current understanding of the roles of CD44 in pathological angiogenesis and the underlying cellular and molecular mechanisms.

Implication of HYBID (Hyaluronan-Binding Protein Involved in Hyaluronan Depolymerization) in Hyaluronan Degradation by Synovial Fibroblasts in Patients with Knee Osteoarthritis

Cell migration-inducing hyaluronidase 1 (CEMIP), also known as hyaluronan (HA)-binding protein involved in HA depolymerization (HYBID), plays a role in HA degradation. CEMIP2, also known as transmembrane protein 2 (TMEM2), possessing a sequence similarity with HYBID, is reported as a hyaluronidase in mice. However, the expression of these molecules in osteoarthritic synovium and their involvement in HA degradation in synovial fluid (SF) from patients with knee osteoarthritis remain elusive. This study examined their expression in synovial tissue and the relationship with molecular weight of HA in SF in knee osteoarthritis patients. Quantification of mRNA demonstrated that HYBID expression is significantly (5.5-fold) higher in osteoarthritic synovium than in normal control synovium, whereas TMEM2 expression level is similar between the two groups. By immunohistochemistry, HYBID was localized mainly to CD68-negative and fibroblast-specific protein 1-positive synovial lining cells and sublining fibroblasts in osteoarthritic synovium. The mRNA expression levels of HYBID, but not TMEM2, in osteoarthritic synovium positively correlated with distribution of lower-molecular-weight HA with below 1000 kDa in SF. HA-degrading activity in osteoarthritic synovial fibroblasts was abrogated by siRNA-mediated knockdown of HYBID. Among the 12 factors examined, IL-6 significantly up-regulated the HYBID expression and HA-degrading activity in osteoarthritic synovial fibroblasts. These data suggest that HYBID overexpressed by IL-6-stimulated synovial fibroblasts is implicated in HA degradation in osteoarthritic synovium.

HYBID (alias KIAA1199/CEMIP) and hyaluronan synthase coordinately regulate hyaluronan metabolism in histamine-stimulated skin fibroblasts

The immune-regulatory compound histamine is involved in the metabolism of the essential skin component hyaluronan (HA). We previously reported that histamine up-regulates the expression of HYBID (hyaluronan-binding protein involved in hyaluronan depolymerization, also called CEMIP or KIAA1199), which plays a key role in HA degradation. However, no information is available about histamine's effects on HA synthase (HAS) expression, the molecular sizes of HA species produced, and histamine receptors and their signaling pathways in skin fibroblasts. Moreover, histamine's effects on photoaged skin remain elusive. Here, we show that histamine increases HA degradation by up-regulating HYBID and down-regulating HAS2 in human skin fibroblasts in a dose- and time-dependent manner and thereby decreases the total amounts and sizes of newly produced HA. Histamine H1 blocker abrogated the histamine effects on HYBID up-regulation, HAS2 suppression, and HA degradation. Histamine H1 agonist exhibited effects on HA levels, composition, and breakdown similar to those of histamine. Of note, blockade of protein kinase Cδ or PI3K-Akt signaling abolished histamine-mediated HYBID stimulation and HAS2 suppression, respectively. Immunohistochemical experiments revealed a significant ∼2-fold increase in tryptase-positive mast cells in photoaged skin, where HYBID and HAS2 expression levels were increased and decreased, respectively, compared with photoprotected skin. These results indicate that histamine controls HA metabolism by up-regulating HYBID and down-regulating HAS2 via distinct signaling pathways downstream of histamine receptor H1. They further suggest that histamine may contribute to photoaged skin damage by skewing HA metabolism toward degradation.

Isoform-specific promotion of breast cancer tumorigenicity by TBX3 involves induction of angiogenesis

TBX3 is a member of the highly conserved family of T-box transcription factors involved in embryogenesis, organogenesis and tumor progression. While the functional role of TBX3 in tumorigenesis has been widely studied, less is known about the specific functions of the different isoforms (TBX3iso1 and TBX3iso2) which differ in their DNA-binding domain. We therefore sought to investigate the functional consequence of this highly conserved splice event as it relates to TBX3-induced tumorigenesis. By utilizing a nude mouse xenograft model, we have identified differential tumorigenic potential between TBX3 isoforms, with TBX3iso1 overexpression more commonly associated with invasive carcinoma and high tumor vascularity. Transcriptional analysis of signaling pathways altered by TBX3iso1 and TBX3iso2 overexpression revealed significant differences in angiogenesis-related genes. Importantly, osteopontin (OPN), a cancer-associated secreted phosphoprotein, was significantly up-regulated with TBX3iso1 (but not TBX3iso2) overexpression. This pattern was observed across three non/weakly-tumorigenic breast cancer cell lines (21PT, 21NT, and MCF7). Up-regulation of OPN in TBX3iso1 overexpressing cells was associated with induction of hyaluronan synthase 2 (HAS2) expression and increased retention of hyaluronan in pericellular matrices. These transcriptional changes were accompanied by the ability to induce endothelial cell vascular channel formation by conditioned media in vitro, which could be inhibited through addition of an OPN neutralizing antibody. Within the TCGA breast cancer cohort, we identified an 8.1-fold higher TBX3iso1 to TBX3iso2 transcript ratio in tumors relative to control, and this ratio was positively associated with high-tumor grade and an aggressive molecular subtype. Collectively, the described changes involving TBX3iso1-dependent promotion of angiogenesis may thus serve as an adaptive mechanism within breast cancer cells, potentially explaining differences in tumor formation rates between TBX3 isoforms in vivo. This study is the first of its kind to report significant functional differences between the two TBX3 isoforms, both in vitro and in vivo.

Role of HYBID (Hyaluronan Binding Protein Involved in Hyaluronan Depolymerization), Alias KIAA1199/CEMIP, in Hyaluronan Degradation in Normal and Photoaged Skin

Photoaged skin is characterized clinically by apparent manifestations such as wrinkles and sagging, and histologically by an accumulation of abnormal elastin and a severe loss of collagen fibers in the dermis. Quantitative and qualitative alterations in elastin and collagens are considered to be responsible for the formation of wrinkles and sagging. However, since the integrity of elastin and collagen fibers in the dermis is maintained by their interactions with hyaluronan (HA) and a proteoglycan network structure, HA degradation may be the initial process, prior to the breakdown of the fibrillary components, leading to wrinkles and sagging in photoaged skin. We have recently discovered a new HA-degrading mechanism mediated by HYBID (hyaluronan binding protein involved in hyaluronan depolymerization), alias KIAA1199/CEMIP, in human skin fibroblasts, and examined the implication of HYBID for skin photoaging. In this review, we give an overview of the characteristics of HYBID and its prospective roles in HA turnover in normal skin and excessive HA degradation in photoaged skin. In addition, we describe our data on the inhibition of HYBID activity and expression by plant extracts in skin fibroblasts; and propose novel strategies to prevent or improve photoaging symptoms, such as skin wrinkling, by inhibition of HYBID-mediated HA degradation.

Characterization and bioactivity of self-assembled anti-angiogenic chondroitin sulfate-ES2-AF nanoparticle conjugate

Background

In the past few years, significant progress has been made in inhibiting neovascularization at the tumor site, cutting off the nutrient supply of the tumor, and inhibiting tumor growth and metastasis. However, many proteins/peptides have the disadvantage of poor stability, short half-life, and uncertain targeting ability. Chemical modification can be used to overcome these disadvantages; many polyethylene glycol-modified proteins/peptides have been approved by US FDA. The purpose of this study was to obtain a novel anti-angiogenic chondroitin sulfate (CS)-peptide nanoparticle conjugate with efficient anti-neovascularization and tumor targeting ability and an acceptable half-life.

Materials and methods

The CS-ES2-AF nanoparticle conjugate was synthesized and characterized using ¹H-nuclear magnetic resonance spectroscopy, transmission electron microscopy, and particle size and zeta potential analyzer. The anti-angiogenic ability was studied using MTT, migration, tube formation, and chick chorioallantoic membrane assays. The targeting ability of CS-ES2-AF was studied by ELISA, surface plasmon resonance, and bioimaging. The pharmacokinetics was also studied.

Results

The CS-ES2-AF could self-assemble into stable nanoparticles in aqueous solution, which significantly enhances its anti-neovascularization activity, tumor targeting more explicit, and prolongs its half-life.

Conclusion

CS is an effective protein/peptide modifier, and CS-ES2-AF displayed good potential in tumor targeting therapy.

Neodermis Formation in Full Thickness Wounds Using an Esterified Hyaluronic Acid Matrix

The role of the dermis is essential for the proper orchestration of all phases of the normal wound healing process. Wounds with seriously damaged or even absent dermis consistently show seriously impaired wound healing and/or long-term complications such as hypertrophic scarring. Replacing a damaged dermis requires a dermal matrix that is compatible with, or even stimulates, the process of wound healing. Hyaluronic acid (HA), in an esterified form, is among the many matrices that are available. HA has been used in a number of indications, such as ulcers (ie, diabetic foot ulcers and venous leg ulcers), trauma, including burns, and for the repair of contractures and hypertrophic scars. The shorter healing time and the decrease of recurring hypertrophy demonstrate the efficiency of HA-derived matrices. Biopsies, taken up to 12 months post-reconstruction show a neodermis that histologically is largely comparable to normal skin, which probably is a function of HA playing such a pivotal role in normal, unwounded skin, as well as in the process of healing.

Managing Wounds with Exposed Bone and Tendon with an Esterified Hyaluronic Acid Matrix (eHAM): A Literature Review and Personal Experience

The loss of extracellular matrix in combination with the exposure of structures such as bone and tendon pose a major challenge; the development of granulation tissue and subsequent reepithelialization over these structures is extremely slow and often may not happen at all. Replacement of the matrix has been shown to significantly increase the chances of healing since, with revascularization of the matrix, a wound bed is created that may either heal by secondary intention or via the application of a skin graft. A literature search on an esterified hyaluronic acid-based matrix (eHAM) returned five articles on the treatment of wounds with tendon and bone loss in which the eHAM was used. The etiologies of the wounds described varied among the articles, as did treatment modalities. However, all of them received proper debridement of necrosis with subsequent (although not always immediately) application of the eHAM. A very high percentage of all wounds reached the different primary endpoints in the studies, which were complete reepithelialization, complete coverage with granulation tissue and/or 10% coverage of the original wound size with epithelium, the latter being a strong indicator of the wound continuing to heal. The individual authors concluded that the esterified hyaluronic acid matrix (eHAM) is a valuable tool to assist in the complete healing of difficult to heal wounds.

Hybrid collagen alginate hydrogel as a platform for 3D tumor spheroid invasion

Extracellular matrix regulates hallmark features of cancer through biochemical and mechanical signals, although mechanistic understanding of these processes remains limited by lack of models that recreate physiology of tumors. To tissue-engineer models that recapitulate three-dimensional architecture and signaling in tumors, there is a pressing need for new materials permitting flexible control of mechanical and biophysical features. We developed a hybrid hydrogel system composed of collagen and alginate to model tumor environments in breast cancer and other malignancies. Material properties of the hydrogel, including stiffness, microstructure and porosimetry, encompass parameters present in normal organs and tumors. The hydrogel possesses a well-organized, homogenous microstructure with adjustable mechanical stiffness and excellent permeability. Upon embedding multicellular tumor spheroids, we constructed a 3D tumor invasion model showing follow-the-leader migration with fibroblasts leading invasion of cancer cells similar to in vivo. We also demonstrated effects of CXCL12-CXCR4 signaling, a pathway implicated in tumor progression and metastasis, in a dual-tumor spheroid invasion model in 3D hydrogels. These studies establish a new hydrogel platform with material properties that can be tuned to investigate effects of environmental conditions on tumor progression, which will advance future studies of cancer cell invasion and response to therapy.

STATEMENT OF SIGNIFICANCE

Our manuscript describes a novel design of hybrid hydrogel system composed of collagen and alginate modeling 3D tumor environments in breast cancer. The hydrogel possesses a well-organized, homogenous microstructure with adjustable mechanical stiffness. Upon embedding tumor spheroids, we successfully showed a 3D tumor invasion model showing follow-the-leader migration with fibroblasts leading invasion of cancer cells similar to in vivo. To the best of our knowledge, this is the first study showing two spheroids invade simultaneously and forming bridge-like connection and effects of chemical gradients in 3D hydrogel environment. This research provides a new model for tumor-stromal interactions in cancer cell migration and establishes a novel hydrogel system for analyzing physical and biochemical signals regulating cancer progression and response to therapy.

Reduction of hyaluronan and increased expression of HYBID (alias CEMIP and KIAA1199) correlate with clinical symptoms in photoaged skin

BACKGROUND

Hyaluronan (HA) metabolism in skin fibroblasts is mediated by HYBID (hyaluronan binding protein involved in hyaluronan depolymerization, alias CEMIP and KIAA1199) and the HA synthases HAS1 and HAS2. However, photoageing-dependent changes in HA and their molecular mechanisms, and the relationship between HA metabolism and clinical symptoms in photoaged skin remain elusive.

OBJECTIVES

We examined the amount, size and tissue distribution of HA and expression levels of HYBID, HAS1 and HAS2 in photoaged skin, and analysed their relationship with the degree of photoageing.

METHODS

Photoageing-dependent changes of HA were investigated by studying skin biopsies isolated from photoprotected and photoexposed areas of the same donors, and the relationships between HA and photoageing symptoms such as skin wrinkling and sagging were examined.

RESULTS

Skin biopsy specimens showed that the amount and size of HA are decreased in photoexposed skin compared with photoprotected skin, and this was accompanied by increased expression of HYBID and decreased expression of HAS1 and HAS2. Histologically, HA staining in the papillary dermis was decreased in photoexposed skin, showing reverse correlation with HYBID expression. HYBID expression in the photoexposed skin directly correlated with skin roughness and sagging parameters, and the reduced HA staining in the papillary dermis in the photoexposed skin positively correlated with these symptoms.

CONCLUSIONS

These data demonstrate that imbalance between HYBID-mediated HA degradation and HAS-mediated HA synthesis may contribute to enhanced HA catabolism in photoaged skin, and suggest that HYBID-mediated HA reduction in the papillary dermis is related to skin wrinkling and sagging of photoaged skin.

Hybrid nanoparticles based on chlorin e6-conjugated hyaluronic acid/poly(l-histidine) copolymer for theranostic application to tumors

The aim of this study is to synthesize multifunctional hybrid nanoparticles composed of hyaluronic acid (HA) and poly(l-histidine) (PHS) with a disulfide linkage and chlorin e6 (HAPHSce6ss) for diagnostic and therapeutic application against breast tumor cells. The reductive end of HA was conjugated with cystamine to make a disulfide linkage (HA-cystamine). PHS was conjugated with Ce6 with the aid of carbodiimide chemistry (PHS-ce6). Then, HA-cystamine was conjugated with the carboxyl group of Ce6 to make an HAPHSce6ss copolymer. Nanoparticles of HAPHSce6ss copolymer have small particle sizes of less than 100 nm and their diameters increased with acidic pH, indicating that HAPHSce6ss nanoparticles have pH-sensitivity. Furthermore, ce6 was activated in the acidic environment and had redox-status in a fluorescence study. In a cell culture study, the nanoparticles were specifically targeted at the CD44 receptor of MDA-MB231 cells while CD44-negative MCF7 cells had no CD44-specificity. The nanoparticles exhibited an enhanced association with cells and were more fluorescent at acidic pH or in the presence of GSH. They inhibited the growth of tumor cells in a CD44 receptor specific or pH-sensitive manner. In an in vivo animal tumor xenograft study using mice, HAPHSce6ss nanoparticles predominantly targeted an MDA-MB231 tumor rather than an MCF7 tumor and effectively inhibited tumor growth. HAPHSce6ss nanoparticles have CD44 specificity, pH/redox dual sensitivity and a fluorescence diagnostic function against tumor cells. We suggest that HAPHSce6ss nanoparticles are a promising candidate for theranostic application to tumors.

Relationship of Tumoral Hyaluronic Acid and Cathepsin D Contents with Histological Type of Gastric Carcinoma

The aim of this work was to evaluate the cytosolic contents of hyaluronic acid (HA) and cathepsin D (CatD) in gastric carcinomas and their possible relationships with the clinicopathological parameters of the tumors. Our study demonstrated a wide variability in the cytosolic levels of HA (mean ± SEM: 3748 ± 411 ng/mg protein) and cathepsin D (52 ± 4 pmol/mg protein) in the tumors of 78 gastric cancer patients. In addition, the tumoral contents of HA and CatD were significantly higher (p<0.005) in diffuse type (HA: 6027 ± 1099 ng/mg protein; CatD: 75 ± 13 pmol/mg protein) than in intestinal type (HA: 2735 ± 242 ng/mg protein; CatD: 42±3 pmol/mg protein) carcinomas. These data suggest that both markers may contribute to the biological characterization of gastric carcinomas.

Hyaluronan Nanoparticles Selectively Target Plaque-Associated Macrophages and Improve Plaque Stability in Atherosclerosis

Hyaluronan is a biologically active polymer, which can be formulated into nanoparticles. In our study, we aimed to probe atherosclerosis-associated inflammation by using hyaluronan nanoparticles and to determine whether they can ameliorate atherosclerosis. Hyaluronan nanoparticles (HA-NPs) were prepared by reacting amine-functionalized oligomeric hyaluronan (HA) with cholanic ester and labeled with a fluorescent or radioactive label. HA-NPs were characterized in vitro by several advanced microscopy methods. The targeting properties and biodistribution of HA-NPs were studied in apoe^-/- mice, which received either fluorescent or radiolabeled HA-NPs and were examined ex vivo by flow cytometry or nuclear techniques. Furthermore, three atherosclerotic rabbits received ⁸⁹Zr-HA-NPs and were imaged by PET/MRI. The therapeutic effects of HA-NPs were studied in apoe^-/- mice, which received weekly doses of 50 mg/kg HA-NPs during a 12-week high-fat diet feeding period. Hydrated HA-NPs were ca. 90 nm in diameter and displayed very stable morphology under hydrolysis conditions. Flow cytometry revealed a 6- to 40-fold higher uptake of Cy7-HA-NPs by aortic macrophages compared to normal tissue macrophages. Interestingly, both local and systemic HA-NP-immune cell interactions significantly decreased over the disease progression. ⁸⁹Zr-HA-NPs-induced radioactivity in atherosclerotic aortas was 30% higher than in wild-type controls. PET imaging of rabbits revealed 6-fold higher standardized uptake values compared to the muscle. The plaques of HA-NP-treated mice contained 30% fewer macrophages compared to control and free HA-treated group. In conclusion, we show favorable targeting properties of HA-NPs, which can be exploited for PET imaging of atherosclerosis-associated inflammation. Furthermore, we demonstrate the anti-inflammatory effects of HA-NPs in atherosclerosis.

Is hyaluronan deposition in the stroma of pancreatic ductal adenocarcinoma of prognostic significance?

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis and the number of PDAC-related deaths is rising. Recently the tumour stroma and in particular one of its main components, hyaluronan (HA), have attracted considerable attention as intravenous hyaluronidase treatment together with conventional chemotherapy considerably prolonged survival in HA-rich PDA patients. We therefore wanted to investigate the prognostic significance of HA deposition in PDA using both antibodies to HA and hyaluronan binding protein (HABP).

MATERIAL AND METHODS

Tissue microarrays of PDAs of 184 patients and pancreatic xenografts tumours were immunohistochemically (IHC) stained for HA using either biotinylated hyaluronic acid binding protein (HABP) or anti-HA antibody.

RESULTS

The pattern of staining with HABP differed significantly from that with antibody IHC. Antibody staining was found both within cancer cells and in the extracellular matrix and staining could not be eliminated by hyaluronidase predigestion of the tissue sections. In contrast, HABP staining was generally confined to the extracellular matrix and was completely abolished by hyaluronidase pretreatment. HA positivity as determined by HABP was associated with larger primary tumours (p = 0.046). There were no correlations between overall survival, disease-free survival and HA expression.

CONCLUSION

Presence of HA alone is not of prognostic importance in PDAC, and IHC with utilization of antibody detection shows no reliable staining pattern and should not be applied for HA IHC.

Hyaluronan oligosaccharides stimulate matrix metalloproteinase and anabolic gene expression in vitro by intervertebral disc cells and annular repair in vivo

The role of hyaluronan (HA) oligosaccharides in disc cell-mediated matrix metalloproteinase (MMP) and anabolic gene expression in vitro and annular repair in vivo were examined. Monolayer and alginate bead cultures of ovine intervertebral disc cells were stimulated with 10-12 mer hyaluronan oligosaccharides (HA-oligos). Annulus fibrosus (AF) monolayers were poorly responsive to the HA-oligos, proMMP-2 levels were marginally elevated and levels were MMP-9 unaffected. ProMMP-2 displayed a strong dose-dependent increase in the nucleus pulposus (NP) monolayers. In AF alginate bead cultures, proMMP-2 and active MMP-9 increased up to day 10, in NP cultures proMMP-2 was progressively converted to active MMP-2 over days 7-10 and active MMP-9 levels were elevated on day 10. A steady decline in MMP-2 and MMP-9 activity was evident over days 2-10 in the non-stimulated NP cultures. Disc cell viabilities were ≥92 ± 5% in all cultures indicating that the HA-oligo was not cytotoxic. Reverse-transcription polymerase chain reaction demonstrated an upregulation in MMP1, MMP113 and ADAMTS1 and the anabolic matrix repair genes ACAN, COL1A1 and COL2A1 in the NP by HA-oligos, whereas AF MMP13, ADAMTS1, ADAMTS4 and ADAMTS5, ACAN and COL2A1 were down-regulated; this differential regulation is expected to promote clearance of granulation/scar tissue from AF defects and matrix replenishment. The AF defect sites contained enlarged annular lamellae in vivo in response to the HA oligos, which is consistent with an active repair response. Masson trichrome and PicroSirius red histology and immunolocalization of type I collagen supported active remodelling in the outer lesion zone by the HA-oligo treatment but not the inner lesion. Copyright © 2016 John Wiley & Sons, Ltd.

Delivery of growth factor-based therapeutics in vascular diseases: Challenges and strategies

Either cardiovascular or peripheral vascular diseases have become the major cause of morbidity and mortality worldwide. Recently, growth factors therapeutics, whatever administrated in form of exogenous growth factors or their relevant genes have been discovered to be an effective strategy for the prevention and therapy of vascular diseases, because of their promoting angiogenesis. Besides, as an alternative, stem cell-based therapy has been also developed in view of their paracrine-mediated effect or ability of differentiation toward angiogenesis-related cells under assistance of growth factors. Despite of being specific and potent, no matter growth factors or stem cells-based therapy, their full clinical transformation is limited from bench to bedside. In this review, the potential choices of therapeutic modes based on types of different growth factors or stem cells were firstly summarized for vascular diseases. The confronted various challenges such as lack of non-invasive delivery method, the physiochemical challenge, the short half-life time, and poor cell survival, were carefully analyzed for these therapeutic modes. Various strategies to overcome these limitations are put forward from the perspective of drug delivery. The expertised design of a suitable delivery form will undoubtedly provide valuable insight into their clinical application in the regenerative medicine.

New Delivery Systems of Stem Cells for Vascular Regeneration in Ischemia

The finances of patients and countries are increasingly overwhelmed with the plague of cardiovascular diseases as a result of having to chronically manage the associated complications of ischemia such as heart failures, neurological deficits, chronic limb ulcers, gangrenes, and amputations. Hence, scientific research has sought for alternate therapies since pharmacological and surgical treatments have fallen below expectations in providing the desired quality of life. The advent of stem cells research has raised expectations with respect to vascular regeneration and tissue remodeling, hence assuring the patients of the possibility of an improved quality of life. However, these supposed encouraging results have been short-lived as the retention, survival, and engraftment rates of these cells appear to be inadequate; hence, the long-term beneficial effects of these cells cannot be ascertained. These drawbacks have led to the relentless research into better ways to deliver stem cells or angiogenic factors (which mobilize stem cells) to the regions of interest to facilitate increased retention, survival, engraftment, and regeneration. This review considered methods, such as the use of scaffolds, retrograde coronary delivery, improved combinations, stem cell pretreatment, preconditioning, stem cell exosomes, mannitol, magnet, and ultrasound-enhanced delivery, homing techniques, and stem cell modulation. Furthermore, the study appraised the possibility of a combination therapy of stem cells and macrophages, considering the enormous role macrophages play in repair, remodeling, and angiogenesis.

Proteomic Profiling of Neuroblastoma Cells Adhesion on Hyaluronic Acid-Based Surface for Neural Tissue Engineering

The microenvironment of neuron cells plays a crucial role in regulating neural development and regeneration. Hyaluronic acid (HA) biomaterial has been applied in a wide range of medical and biological fields and plays important roles in neural regeneration. PC12 cells have been reported to be capable of endogenous NGF synthesis and secretion. The purpose of this research was to assess the effect of HA biomaterial combining with PC12 cells conditioned media (PC12 CM) in neural regeneration. Using SH-SY5Y cells as an experimental model, we found that supporting with PC12 CM enhanced HA function in SH-SY5Y cell proliferation and adhesion. Through RP-nano-UPLC-ESI-MS/MS analyses, we identified increased expression of HSP60 and RanBP2 in SH-SY5Y cells grown on HA-modified surface with cotreatment of PC12 CM. Moreover, we also identified factors that were secreted from PC12 cells and may promote SH-SY5Y cell proliferation and adhesion. Here, we proposed a biomaterial surface enriched with neurotrophic factors for nerve regeneration application.

Provisional matrix: A role for versican and hyaluronan

Hyaluronan and versican are extracellular matrix (ECM) components that are enriched in the provisional matrices that form during the early stages of development and disease. These two molecules interact to create pericellular "coats" and "open space" that facilitate cell sorting, proliferation, migration, and survival. Such complexes also impact the recruitment of leukocytes during development and in the early stages of disease. Once thought to be inert components of the ECM that help hold cells together, it is now quite clear that they play important roles in controlling cell phenotype, shaping tissue response to injury and maintaining tissue homeostasis. Conversion of hyaluronan-/versican-enriched provisional matrix to collagen-rich matrix is a "hallmark" of tissue fibrosis. Targeting the hyaluronan and versican content of provisional matrices in a variety of diseases including, cardiovascular disease and cancer, is becoming an attractive strategy for intervention.

Hyaluronic Acid--an "Old" Molecule with "New" Functions: Biosynthesis and Depolymerization of Hyaluronic Acid in Bacteria and Vertebrate Tissues Including during Carcinogenesis

Hyaluronic acid is an evolutionarily ancient molecule commonly found in vertebrate tissues and capsules of some bacteria. Here we review modern data regarding structure, properties, and biological functions of hyaluronic acid in mammals and Streptococcus spp. bacteria. Various aspects of biogenesis and degradation of hyaluronic acid are discussed, biosynthesis and degradation metabolic pathways for glycosaminoglycan together with involved enzymes are described, and vertebrate and bacterial hyaluronan synthase genes are characterized. Special attention is given to the mechanisms underlying the biological action of hyaluronic acid as well as the interaction between polysaccharide and various proteins. In addition, all known signaling pathways involving hyaluronic acid are outlined. Impaired hyaluronic acid metabolism, changes in biopolymer molecular weight, hyaluronidase activity, and enzyme isoforms often accompany carcinogenesis. The interaction between cells and hyaluronic acid from extracellular matrix that may be important during malignant change is discussed. An expected role for high molecular weight hyaluronic acid in resistance of naked mole rat to oncologic diseases and the protective role of hyaluronic acid in bacteria are discussed.

Hyaluronan oligosaccharides promote diabetic wound healing by increasing angiogenesis

BACKGROUND

Hyaluronan (also known as hyaluronic acid) oligosaccharides (O-HA) can promote angiogenesis and wound healing; however, there are few reports on whether O-HA also plays a role in healing wounds of diabetic patients.

METHODS

In this study, we prepared a special ointment containing a mixture of hyaluronan fragments from 2 to 10 disaccharide units and investigated its effects on healing the wounds of diabetic rats.

RESULTS

We found that O-HA significantly increases proliferation, migration, and tube formation of endothelial cells under high glucose conditions, and topical administration of O-HA ointment promotes wound healing by increasing angiogenesis in the wounded area of the skin. The underlying mechanisms are that O-HA increases the phosphorylation of Src and ERK, and expression of TGF beta1, thereby increasing angiogenesis.

CONCLUSIONS

This suggests that topical application of O-HA could be a useful method by which to treat diabetic wounds in clinical practice.

Hyaluronan Upregulates Mitochondrial Biogenesis and Reduces Adenoside Triphosphate Production for Efficient Mitochondrial Function in Slow-Proliferating Human Mesenchymal Stem Cells

Hyaluronan-coated surfaces preserve the proliferation and differentiation potential of mesenchymal stem cells by prolonging their G1-phase transit, which maintains cells in a slow-proliferative mode. Mitochondria are known to play a crucial role in stem cell self-renewal and differentiation. In this study, for the first time, the metabolic mechanism underlying the hyaluronan-regulated slow-proliferative maintenance of stem cells was investigated by evaluating mitochondrial functions. Human placenta-derived mesenchymal stem cells (PDMSCs) cultured on hyaluronan-coated surfaces at 0.5, 3.0, 5.0, and 30 µg/cm² were found to have an average 58% higher mitochondrial mass and an increase in mitochondrial DNA copy number compared to noncoated tissue culture surfaces (control), as well as a threefold increase in the gene expression of the mitochondrial biogenesis-related gene PGC-1α. Increase in mitochondrial biogenesis led to a hyaluronan dose-dependent increase in mitochondrial membrane potential, ATP content, and oxygen consumption rate, with reactive oxygen species levels shown to be at least three times lower compared to the control. Although hyaluronan seemed to favor mitochondrial function, cell entry into a hyaluronan-regulated slow-proliferative mode led to a fivefold reduction in ATP production and coupling efficiency levels. Together, these results suggest that hyaluronan-coated surfaces influence the metabolic proliferative state of stem cells by upregulating mitochondrial biogenesis and function with controlled ATP production. This more efficiently meets the energy requirements of slow-proliferating PDMSCs. A clear understanding of the metabolic mechanism induced by hyaluronan in stem cells will allow future applications that may overcome the current limitations faced in stem cell culture. Stem Cells 2016;34:2512-2524.

Hyaluronidase To Enhance Nanoparticle-Based Photodynamic Tumor Therapy

Photodynamic therapy (PDT) is considered as a safe and selective way to treat a wide range of cancers as well as nononcological disorders. However, as oxygen is required in the process of PDT, the hypoxic tumor microenvironment has largely limited the efficacy of PDT to treat tumors especially those with relatively large sizes. To this end, we uncover that hyaluronidase (HAase), which breaks down hyaluronan, a major component of extracellular matrix (ECM) in tumors, would be able to enhance the efficacy of nanoparticle-based PDT for in vivo cancer treatment. It is found that the administration of HAase would lead to the increase of tumor vessel densities and effective vascular areas, resulting in increased perfusion inside the tumor. As a result, the tumor uptake of nanomicelles covalently linked with chlorine e6 (NM-Ce6) would be increased by ∼2 folds due to the improved "enhanced permeability and retention" (EPR) effect, while the tumor oxygenation level also shows a remarkable increase, effectively relieving the hypoxia state inside the tumor. Those effects taken together offer significant benefits in greatly improving the efficacy of PDT delivered by nanoparticles. Taking advantage of the effective migration of HAase from the primary tumor to its drainage sentinel lymph nodes (SLNs), we further demonstrate that this strategy would be helpful to the treatment of metastatic lymph nodes by nanoparticle-based PDT. Lastly, both enhanced EPR effect of NM-Ce6 and relieved hypoxia state of tumor are also observed after systemic injection of modified HAase, proving its potential for clinical translation. Therefore, our work presents a new concept to improve the efficacy of nanomedicine by modulating the tumor microenvironment.

Hydrogels for therapeutic cardiovascular angiogenesis

Acute myocardial infarction (MI) caused by ischemia is the most common cause of cardiac dysfunction. While growth factor or cell therapy is promising, the retention of bioactive agents in the highly vascularized myocardium is limited and prevents sustained activation needed for adequate cellular responses. Various types of biomaterials with different physical and chemical properties have been developed to improve the localized delivery of growth factor and/or cells for therapeutic angiogenesis in ischemic tissues. Hydrogels are particularly advantageous as carrier systems because they are structurally similar to the tissue extracellular matrix (ECM), they can be processed under relatively mild conditions and can be delivered in a minimally invasive manner. Moreover, hydrogels can be designed to degrade in a timely fashion that coincides with the angiogenic process. For these reasons, hydrogels have shown great potential as pro-angiogenic matrices. This paper reviews a few of the hydrogel systems currently being applied together with growth factor delivery and/or cell therapy to promote therapeutic angiogenesis in ischemic tissues, with emphasis on myocardial applications.

Smart Nanoparticles Based on Hyaluronic Acid for Redox-Responsive and CD44 Receptor-Mediated Targeting of Tumor

BACKGROUND

Since aggressive cancer cells highly express the CD44 receptor compared to normal cells, hyaluronic acid (HA) can be used for CD44 targeting molecule. Since glutathione (GSH) level is normally elevated in the intracellular compartment and in the tumor cell, the fact that disulfide bond can be cleaved by GSH is widely used for intracellular drug delivery.

METHODS

HA was connected with poly(DL-lactide-co-glycolide) (PLGA) using disulfide linkage, and then a diblock copolymer (HAssLG) was prepared. Doxorubicin (DOX)-loaded HAssLG nanoparticles were prepared by dialysis procedures.

RESULTS AND DISCUSSION

DOX-loaded HAssLG nanoparticles have spherical shapes with small particle size of less than 300 nm. In fluorescence measurement, DOX was dose-dependently liberated from nanoparticles by the addition of GSH. DOX release rate from HAssLG nanoparticles was increased by the addition of GSH. To confirm CD44 receptor-mediated endocytosis of nanoparticles, CD44-positive MDA-MB231 cells were employed and fluorescence intensity was strong when nanoparticles were treated to tumor cells. However, fluorescence intensity was significantly decreased through blocking of the CD44 receptor by pretreatment of cells with free HA. Fluorescence intensity of cells was increased again when GSH was added, indicating that HAssLG nanoparticles have CD44 receptor targetability and potential of redox-responsive drug delivery. For animal imaging study, CD44-positive MDA-MB231 cells and CD44-negative NIH3T3 cells were simultaneously implanted into the right flank and left flank of mice, respectively. Fluorescence intensity was significantly stronger at tumor mass of MDA-MB231 cells than solid mass of NIH3T3 cells, indicating that HAssLG nanoparticles were specifically delivered to tumor cells.

CONCLUSIONS

The results indicated that HAssLG nanoparticles have specificity against the CD44 receptor and can be used for anticancer drug targeting. We recommend HAssLG nanoparticles as a promising vehicle for cancer drug targeting.

Hyaluronan-induced VEGF-C promotes fibrosis-induced lymphangiogenesis via Toll-like receptor 4-dependent signal pathway

Hyaluronan (HA), a component of the extracellular matrix, modulates cellular behavior including angiogenesis. However, little is known about the effect of HA on lymphangiogenesis in fibrosis model. In this study, we investigated the roles of HA in lymphangiogenesis of unilateral ureteral obstruction (UUO). We found that HA cooperated synergistically with vascular endothelial cell growth factor-C to stimulate capillary-like tube formation and increase migration of cells in a haptotaxis assay. Accumulation of HA in the cortical interstitial space was positively correlated with the number of lymphatic vessels after UUO. Depletion of macrophages with clodronate decreased UUO-induced HA accumulation and lymphangiogenesis. Additionally, hyaluronan synthase (HAS) mRNA expression and HA production were increased in bone marrow-derived macrophages upon stimulation with TGF-β1. Transfer of mHAS2 and mHAS3 knock-down CD11b-positive macrophages to SCID mice resulted in a partial decrease in UUO-induced lymphangiogenesis. HA increased expression of vascular endothelial cell growth factor-C in macrophages. Vascular endothelial cell growth factor-C expression and LYVE-1-positive lymphatic area was significantly lower in the UUO-kidney from TLR4 null mice than that from TLR4 wild-type mice. Collectively, these results suggest that HA increases lymphangiogenesis in renal fibrosis model and also stimulates vascular endothelial cell growth factor-C production from macrophages through Toll-like receptor 4-dependent signal pathway.

Emerging roles for hyaluronidase in cancer metastasis and therapy

Hyaluronidases are a family of five human enzymes that have been differentially implicated in the progression of many solid tumor types, both clinically and in functional studies. Advances in the past 5 years have clarified many apparent contradictions: (1) by demonstrating that specific hyaluronidases have alternative substrates to hyaluronan (HA) or do not exhibit any enzymatic activity, (2) that high-molecular weight HA polymers elicit signaling effects that are opposite those of the hyaluronidase-digested HA oligomers, and (3) that it is actually the combined overexpression of HA synthesizing enzymes with hyaluronidases that confers tumorigenic potential. This review examines the literature supporting these conclusions and discusses novel mechanisms by which hyaluronidases impact invasive tumor cell processes. In addition, a detailed structural and functional comparison of the hyaluronidases is presented with insights into substrate selectivity and potential for therapeutic targeting. Finally, technological advances in targeting hyaluronidase for tumor imaging and cancer therapy are summarized.