Inhibition of hyaluronic acid formation sensitizes chronic myelogenous leukemia to treatment with doxorubicin

Targeting the extracellular matrix for immunomodulation: applications in drug delivery and cell therapies

Host immune cells interact bi-directionally with their extracellular matrix (ECM) to receive and deposit molecular signals, which orchestrate cellular activation, proliferation, differentiation, and function to maintain healthy tissue homeostasis. In response to pathogens or damage, immune cells infiltrate diseased sites and synthesize critical ECM molecules such as glycoproteins, proteoglycans, and glycosaminoglycans to promote healing. When the immune system misidentifies pathogens or fails to survey damaged cells effectively, maladies such as chronic inflammation, autoimmune diseases, and cancer can develop. In these conditions, it is essential to restore balance to the body through modulation of the immune system and the ECM. This review details the components of dysregulated ECM implicated in pathogenic environments and therapeutic approaches to restore tissue homeostasis. We evaluate emerging strategies to overcome inflamed, immune inhibitory, and otherwise diseased microenvironments, including mechanical stimulation, targeted proteases, adoptive cell therapy, mechanomedicine, and biomaterial-based cell therapeutics. We highlight various strategies that have produced efficacious responses in both pre-clinical and human trials and identify additional opportunities to develop next-generation interventions. Significantly, we identify a need for therapies to address dense or fibrotic tissue for the treatment of organ tissue damage and various cancer subtypes. Finally, we conclude that therapeutic techniques that disrupt, evade, or specifically target the pathogenic microenvironment have a high potential for improving therapeutic outcomes and should be considered a priority for immediate exploration. A schematic showing the various methods of extracellular matrix disruption/targeting in both fibrotic and cancerous environments. a Biomaterial-based cell therapy can be used to deliver anti-inflammatory cytokines, chemotherapeutics, or other factors for localized, slow release of therapeutics. b Mechanotherapeutics can be used to inhibit the deposition of molecules such as collagen that affect stiffness. c Ablation of the ECM and target tissue can be accomplished via mechanical degradation such as focused ultrasound. d Proteases can be used to improve the distribution of therapies such as oncolytic virus. e Localization of therapeutics such as checkpoint inhibitors can be improved with the targeting of specific ECM components, reducing off-target effects and toxicity.

Targeting the Tumor Extracellular Matrix by the Natural Molecule 4-Methylumbelliferone: A Complementary and Alternative Cancer Therapeutic Strategy

In antineoplastic therapy, one of the challenges is to adjust the treatment to the needs of each patient and reduce the toxicity caused by conventional antitumor strategies. It has been demonstrated that natural products with antitumoral properties are less toxic than chemotherapy and radiotherapy. Also, using already developed drugs allows developing substantially less costly methods for the discovery of new treatments than traditional drug development. Candidate molecules proposed for drug repositioning include 4-methylumbelliferone (4-MU), an orally available dietetic product, derivative of coumarin and mainly found in the plant family Umbelliferae or Apiaceae. 4-MU specifically inhibits the synthesis of glycosaminoglycan hyaluronan (HA), which is its main mechanism of action. This agent reduces the availability of HA substrates and inhibits the activity of different HA synthases. However, an effect independent of HA synthesis has also been observed. 4-MU acts as an inhibitor of tumor growth in different types of cancer. Particularly, 4-MU acts on the proliferation, migration and invasion abilities of tumor cells and inhibits the progression of cancer stem cells and the development of drug resistance. In addition, the effect of 4-MU impacts not only on tumor cells, but also on other components of the tumor microenvironment. Specifically, 4-MU can potentially act on immune, fibroblast and endothelial cells, and pro-tumor processes such as angiogenesis. Most of these effects are consistent with the altered functions of HA during tumor progression and can be interrupted by the action of 4-MU. While the potential advantage of 4-MU as an adjunct in cancer therapy could improve therapeutic efficacy and reduce toxicities of other antitumoral agents, the greatest challenge is the lack of scientific evidence to support its approval. Therefore, crucial human clinical studies have yet to be done to respond to this need. Here, we discuss and review the possible applications of 4-MU as an adjunct in conventional antineoplastic therapies, to achieve greater therapeutic success. We also describe the main proposed mechanisms of action that promote an increase in the efficacy of conventional antineoplastic strategies in different types of cancer and prospects that promote 4-MU repositioning and application in cancer therapy.

Hyaluronic Acid-Modified and Doxorubicin-Loaded Gold Nanoparticles and Evaluation of Their Bioactivity

Functionalized gold nanoparticles (AuNPs) have been successfully used in many fields as a result of having low cytotoxicity, good biocompatibility, excellent optical properties, and their ability to target cancer cells. Here, we synthesized AuNP carriers that were modified by hyaluronic acid (HA), polyethylene glycol (PEG), and adipic dihydrazide (ADH). The antitumor drug doxorubicin (Dox) was loaded into AuNP carriers and attached chemically. The Au nanocomposite AuNPs@MPA-PEG-HA-ADH-Dox was able to disperse uniformly in aqueous solution, with a diameter of 15 nm. The results of a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that AuNP carriers displayed very little toxicity toward cells in high doses, although the antitumor properties of Au nanocomposites were significantly enhanced. Cellular uptake experiments demonstrated that AuNPs modified with hyaluronic acid were more readily ingested by HepG2 and HCT-116 cells, as they have a large number of CD44 receptors. A series of experiments measuring apoptosis such as Rh123 and annexin V-FITC staining, and analysis of mitochondrial membrane potential (MMP) analysis, indicated that apoptosis played a role in the inhibition of cell proliferation by AuNPs@MPA-PEG-HA-ADH-Dox. Excessive production of reactive oxygen species (ROS) was the principal mechanism by which the Au nanocomposites inhibited cell proliferation, leading to apoptosis. Thus, the Au nanocomposites, which allowed cell imaging in real-time and induced apoptosis in specific cell types, represent theragnostic agents with potential for future clinical applications in bowel cancer.

Extracellular Matrix in the Tumor Microenvironment and Its Impact on Cancer Therapy

Solid tumors are complex organ-like structures that consist not only of tumor cells but also of vasculature, extracellular matrix (ECM), stromal, and immune cells. Often, this tumor microenvironment (TME) comprises the larger part of the overall tumor mass. Like the other components of the TME, the ECM in solid tumors differs significantly from that in normal organs. Intratumoral signaling, transport mechanisms, metabolisms, oxygenation, and immunogenicity are strongly affected if not controlled by the ECM. Exerting this regulatory control, the ECM does not only influence malignancy and growth of the tumor but also its response toward therapy. Understanding the particularities of the ECM in solid tumor is necessary to develop approaches to interfere with its negative effect. In this review, we will also highlight the current understanding of the physical, cellular, and molecular mechanisms by which the pathological tumor ECM affects the efficiency of radio-, chemo-, and immunotherapy. Finally, we will discuss the various strategies to target and modify the tumor ECM and how they could be utilized to improve response to therapy.

miR-34b/c regulates doxorubicin-induced myocardial cell injury through ITCH

Objective: To determine the underlying mechanism of miR-34b/c in regulating doxorubicin (Dox)-induced myocardial cell injury.Methods: The viability of mouse myocardial cells HL-1 was detected by MTT assay. The apoptosis of HL-1 cells was detected by TUNEL assay. mRNA expressions of ITCH, TNF-α and IL-6 were measured by qRT-PCR. Protein levels of ITCH, NF-κB, TNF-α and IL-6 were measured by western blot. Dual luciferase assay was performed to detect the regulation of miR-34b/c on ITCH. Mouse model of cardiomyopathy was induced by intraperitoneal injection of Dox.Results: Dox reduced HL-1 cell viability and activated NF-κB pathway in HL-1 cells. miR-34b/c expressions were gradually up-regulated and ITCH expression was gradually down-regulated in Dox-treated HL-1 cells. miR-34b/c expression had negative correlation with the mRNA expression of ITCH. Besides, ITCH was a target of miR-34b/c. miR-34b/c mimic reduced cell viability, suppressed ITCH expression, increased TNF-α and IL-6 level, and promoted NF-κB expression in nucleus and cytoplasm of HL-1 cells. Whereas silencing miR-34 protected HL-1 cells through regulating ITCH. Finally, we demonstrated miR-34 antagomir-protected myocardial cells in mouse model of cardiomyopathy.Conclusion: miR-34b/c decreased HL-1 cell viability and promoted the secretion of proinflammatory cytokines in Dox-induced myocardial cells through ITCH/NF-κB pathway.

4-Methylumbelliferone Inhibits Cancer Stem Cell Activation and Overcomes Chemoresistance in Ovarian Cancer

We have recently shown that the extracellular matrix molecule hyaluronan (HA) plays a role in the development of ovarian cancer chemoresistance. This present study determined if HA production is increased in chemotherapy-resistant ovarian cancers and if the HA inhibitor 4-methylubelliferone (4-MU) can overcome chemoresistance to the chemotherapeutic drug carboplatin (CBP) and inhibit spheroid formation and the expression of cancer stem cell (CSC) markers. We additionally assessed whether 4-MU could inhibit in vivo invasion of chemoresistant primary ovarian cancer cells in the chicken embryo chorioallantoic membrane (CAM) assay. The expression of the HA synthases HAS2 and HAS3 was significantly increased in chemoresistant compared to chemosensitive primary ovarian cancer cells isolated from patient ascites. 4-MU significantly inhibited HA production, cell survival, and spheroid formation of chemoresistant serous ovarian cancer cells. In combination with CBP, 4-MU treatment significantly decreased ovarian cancer cell survival and increased apoptosis of chemoresistant primary cells compared to CBP alone. 4-MU significantly reduced spheroid formation, expression of CSC markers ALDH1A1 and ABCG2 in primary cell spheroid cultures, and ALDH1 immunostaining in patient-derived tissue explant assays following treatment with CBP. Furthermore, 4-MU was very effective at inhibiting in vivo invasion of chemoresistant primary cells in CAM assays. Inhibition of HA is therefore a promising new strategy to overcome chemoresistance and to improve ovarian cancer survival.