Telomerase Responsive Delivery of Doxorubicin from Mesoporous Silica Nanoparticles in Multiple Malignancies: Therapeutic Efficacies against Experimental Aggressive Murine Lymphoma

Telomerase: a nexus between cancer nanotherapy and circadian rhythm

Cancer represents a complex disease category defined by the unregulated proliferation and dissemination of anomalous cells within the human body. According to the GLOBOCAN 2020 report, the year 2020 witnessed the diagnosis of approximately 19.3 million new cases of cancer and 10.0 million individuals succumbed to the disease. A typical cell eventually becomes cancerous because of a long-term buildup of genetic instability and replicative immortality. Telomerase is a crucial regulator of cancer progression as it induces replicative immortality. In cancer cells, telomerase inhibits apoptosis by elongating the length of the telomeric region, which usually protects the genome from shortening. Many nanoparticles are documented as being available for detecting the presence of telomerase, and many were used as delivery systems to transport drugs. Furthermore, telomere homeostasis is regulated by the circadian time-keeping machinery, leading to 24-hour rhythms in telomerase activity and TERT mRNA expression in mammals. This review provides a comprehensive discussion of various kinds of nanoparticles used in telomerase detection, inhibition, and multiple drug-related pathways, as well as enlightens an imperative association between circadian rhythm and telomerase activity from the perspective of nanoparticle-based anticancer therapeutics.

Targeting Telomere Dynamics as an Effective Approach for the Development of Cancer Therapeutics

Telomere is a protective structure located at the end of chromosomes of eukaryotes, involved in maintaining the integrity and stability of the genome. Telomeres play an essential role in cancer progression; accordingly, targeting telomere dynamics emerges as an effective approach for the development of cancer therapeutics. Targeting telomere dynamics may work through multifaceted molecular mechanisms; those include the activation of anti-telomerase immune responses, shortening of telomere lengths, induction of telomere dysfunction and constitution of telomerase-responsive drug release systems. In this review, we summarize a wide variety of telomere dynamics-targeted agents in preclinical studies and clinical trials, and reveal their promising therapeutic potential in cancer therapy. As shown, telomere dynamics-active agents are effective as anti-cancer chemotherapeutics and immunotherapeutics. Notably, these agents may display efficacy against cancer stem cells, reducing cancer stem levels. Furthermore, these agents can be integrated with the capability of tumor-specific drug delivery by the constitution of related nanoparticles, antibody drug conjugates and HSA-based drugs.

Insights into the role of nucleotide methylation in metabolic-associated fatty liver disease

Metabolic-associated fatty liver disease (MAFLD) is a chronic liver disease characterized by fatty infiltration of the liver. In recent years, the MAFLD incidence rate has risen and emerged as a serious public health concern. MAFLD typically progresses from the initial hepatocyte steatosis to steatohepatitis and then gradually advances to liver fibrosis, which may ultimately lead to cirrhosis and carcinogenesis. However, the potential evolutionary mechanisms still need to be clarified. Recent studies have shown that nucleotide methylation, which was directly associated with MAFLD's inflammatory grading, lipid synthesis, and oxidative stress, plays a crucial role in the occurrence and progression of MAFLD. In this review, we highlight the regulatory function and associated mechanisms of nucleotide methylation modification in the progress of MAFLD, with a particular emphasis on its regulatory role in the inflammation of MAFLD, including the regulation of inflammation-related immune and metabolic microenvironment. Additionally, we summarize the potential value of nucleotide methylation in the diagnosis and treatment of MAFLD, intending to provide references for the future investigation of MAFLD.

Functionalization of Nanoparticulate Drug Delivery Systems and Its Influence in Cancer Therapy

Research into the application of nanocarriers in the delivery of cancer-fighting drugs has been a promising research area for decades. On the other hand, their cytotoxic effects on cells, low uptake efficiency, and therapeutic resistance have limited their therapeutic use. However, the urgency of pressing healthcare needs has resulted in the functionalization of nanoparticles' (NPs) physicochemical properties to improve clinical outcomes of new, old, and repurposed drugs. This article reviews recent research on methods for targeting functionalized nanoparticles to the tumor microenvironment (TME). Additionally, the use of relevant engineering techniques for surface functionalization of nanocarriers (liposomes, dendrimers, and mesoporous silica) and their critical roles in overcoming the current limitations in cancer therapy-targeting ligands used for targeted delivery, stimuli strategies, and multifunctional nanoparticles-were all reviewed. The limitations and future perspectives of functionalized nanoparticles were also finally discussed. Using relevant keywords, published scientific literature from all credible sources was retrieved. A quick search of the literature yielded almost 400 publications. The subject matter of this review was addressed adequately using an inclusion/exclusion criterion. The content of this review provides a reasonable basis for further studies to fully exploit the potential of these nanoparticles in cancer therapy.

Improving anti-cancer drug delivery performance of magnetic mesoporous silica nanocarriers for more efficient colorectal cancer therapy

BACKGROUND

Improving anti-cancer drug delivery performance can be achieved through designing smart and targeted drug delivery systems (DDSs). For this aim, it is important to evaluate overexpressed biomarkers in the tumor microenvironment (TME) for optimizing DDSs.

MATERIALS AND METHODS

Herein, we designed a novel DDS based on magnetic mesoporous silica core-shell nanoparticles (SPION@MSNs) in which release of doxorubicin (DOX) at the physiologic pH was blocked with gold gatekeepers. In this platform, we conjugated heterofunctional polyethylene glycol (PEG) onto the outer surface of nanocarriers to increase their biocompatibility. At the final stage, an epithelial cell adhesion molecule (EpCAM) aptamer as an active targeting moiety was covalently attached (Apt-PEG-Au@NPs-DOX) for selective drug delivery to colorectal cancer (CRC) cells. The physicochemical properties of non-targeted and targeted nanocarriers were fully characterized. The anti-cancer activity, cellular internalization, and then the cell death mechanism of prepared nanocarriers were determined and compared in vitro. Finally, tumor inhibitory effects, biodistribution and possible side effects of the nanocarriers were evaluated in immunocompromised C57BL/6 mice bearing human HT-29 tumors.

RESULTS

Nanocarriers were successfully synthesized with a mean final size diameter of 58.22 ± 8.54 nm. Higher cytotoxicity and cellular uptake of targeted nanocarriers were shown in the EpCAM-positive HT-29 cells as compared to the EpCAM-negative CHO cells, indicating the efficacy of aptamer as a targeting agent. In vivo results in a humanized mouse model showed that targeted nanocarriers could effectively increase DOX accumulation in the tumor site, inhibit tumor growth, and reduce the adverse side effects.

CONCLUSION

These results suggest that corporation of a magnetic core, gold gatekeeper, PEG and aptamer can strongly improve drug delivery performance and provide a theranostic DDS for efficient CRC therapy.

Stimulus-Responsive Nanomedicines for Disease Diagnosis and Treatment

Stimulus-responsive drug delivery systems generally aim to release the active pharmaceutical ingredient (API) in response to specific conditions and have recently been explored for disease treatments. These approaches can also be extended to molecular imaging to report on disease diagnosis and management. The stimuli used for activation are based on differences between the environment of the diseased or targeted sites, and normal tissues. Endogenous stimuli include pH, redox reactions, enzymatic activity, temperature and others. Exogenous site-specific stimuli include the use of magnetic fields, light, ultrasound and others. These endogenous or exogenous stimuli lead to structural changes or cleavage of the cargo carrier, leading to release of the API. A wide variety of stimulus-responsive systems have been developed-responsive to both a single stimulus or multiple stimuli-and represent a theranostic tool for disease treatment. In this review, stimuli commonly used in the development of theranostic nanoplatforms are enumerated. An emphasis on chemical structure and property relationships is provided, aiming to focus on insights for the design of stimulus-responsive delivery systems. Several examples of theranostic applications of these stimulus-responsive nanomedicines are discussed.

A novel strategy for the diagnosis, prognosis, treatment, and chemoresistance of hepatocellular carcinoma: DNA methylation

The cancer mortality rate of hepatocellular carcinoma (HCC) is the second highest in the world and the therapeutic options are limited. The incidence of this deadly cancer is rising at an alarming rate because of the high degree of resistance to chemo- and radiotherapy, lack of proper, and adequate vaccination to hepatitis B, and lack of consciousness and knowledge about the disease itself and the lifestyle of the people. DNA methylation and DNA methylation-induced epigenetic alterations, due to their potential reversibility, open the access to develop novel biomarkers and therapeutics for HCC. The contribution to these epigenetic changes in HCC development still has not been thoroughly summarized. Thus, it is necessary to better understand the new molecular targets of HCC epigenetics in HCC diagnosis, prevention, and treatment. This review elaborates on recent key findings regarding molecular biomarkers for HCC early diagnosis, prognosis, and treatment. Currently emerging epigenetic drugs for the treatment of HCC are summarized. In addition, combining epigenetic drugs with nonepigenetic drugs for HCC treatment is also mentioned. The molecular mechanisms of DNA methylation-mediated HCC resistance are reviewed, providing some insights into the difficulty of treating liver cancer and anticancer drug development.

Mesoporous Silica Nanoparticles as Carriers for Therapeutic Biomolecules

The enormous versatility of mesoporous silica nanoparticles permits the creation of a large number of nanotherapeutic systems for the treatment of cancer and many other pathologies. In addition to the controlled release of small drugs, these materials allow a broad number of molecules of a very different nature and sizes. In this review, we focus on biogenic species with therapeutic abilities (proteins, peptides, nucleic acids, and glycans), as well as how nanotechnology, in particular silica-based materials, can help in establishing new and more efficient routes for their administration. Indeed, since the applicability of those combinations of mesoporous silica with bio(macro)molecules goes beyond cancer treatment, we address a classification based on the type of therapeutic action. Likewise, as illustrative content, we highlight the most typical issues and problems found in the preparation of those hybrid nanotherapeutic materials.

Nanomedicine - a promising therapy for hematological malignancies

Hematological tumors are a group of diseases defined as the clonal proliferation of blood-forming cells. In recent years, incidences of hematological malignancies have increased. Traditional methods of diagnosing hematological tumors are primarily based on observing morphological features under light microscopy, and molecular diagnostics and immunological indicators are powerful auxiliary diagnostic methods. However, traditional methods cannot efficiently identify tumor markers and limit the efficiency and accuracy of diagnosis. Although treatment methods have been improved continuously, chemotherapy remains a primary technique for the treatment of hematological tumors. Traditional chemotherapy exhibits poor drug selectivity and lacks good biocompatibility and pharmacokinetic properties. The therapeutic effect is not ideal and the risk of toxic side effects is high. The nanosize and surface charge properties of nanodrugs are effective in improving drug delivery efficiency. The high load and rich surface modification methods of nanomaterials provide various possibilities for improving the biocompatibility and pharmacokinetics of drugs, as well as the targeting of drugs. In addition, a nanomedicine loading platform can load multiple drugs simultaneously and design the optimal proportion of combined drug schemes, which can improve the efficacy of drugs and reduce the occurrence of drug resistance. With their unique physical and chemical properties and biological characteristics, the application of nanoparticles in the diagnosis and treatment of hematological tumors has received considerable attention. In this review, we summarize recent advances in the application of various types of nanostructures for the diagnosis and treatment of hematological malignancies, investigate the advantages of nanomedicine compared with the traditional diagnosis and treatment of hematological tumors, and discuss their biological security and application prospects.

New Advances in In Vivo Applications of Gated Mesoporous Silica as Drug Delivery Nanocarriers

One appealing concept in the field of hybrid materials is related to the design of gated materials. These materials are prepared in such a way that the release of chemical or biochemical species from voids of porous supports to a solution is triggered upon the application of external stimuli. Such gated materials are mainly composed of two subunits: i) a porous inorganic scaffold in which a cargo is stored, and ii) certain molecular or supramolecular entities, grafted onto the external surface, that can control mass transport from the interior of the pores. On the basis of this concept, a large number of examples are developed in the past ten years. A comprehensive overview of gated materials used in drug delivery applications in in vivo models from 2016 to date is thus given here.

Oxovanadium(V) and Dioxomolybdenum(VI) Complexes of Amide-Imine Conjugates: Structures, Catalytic and Antitumor Activities

Three new amide-imine conjugates, namely [(E)-2-hydroxy-N'-((2-hydroxynaphthalen-1-yl)methylene)benzohydrazide] (SALNP), [(E)-N'-(4-(diethylamino)-2-hydroxybenzylidene)-2-hydroxybenzohydrazide] (SALSD), and [(E)-N'-(3-ethoxy-4-hydroxybenzylidene)-2-hydroxybenzohydrazide] (SALVN), derived by reacting 2-hydroxybenzohydrazide (SAL) with three different aldehyde, 2-hydroxynapthaldehyde, 4-(diethylamino)-2-hydroxybenzaldehyde, and 3-ethoxy-4-hydroxybenzaldehyde, respectively. Three mononuclear oxovanadium(V) and two μ_oxo-bridged dinuclear molybdenum(VI) complexes have been synthesized using SALNP and SALSD. Besides, SALVN is used to prepare oxovanadium(V) and dioxomolybdenum(VI) complexes. All five metal complexes along with three amide-imine conjugates are characterized by single crystal XRD analysis. Some of them have been explored as catalyst for oxidation of alkyl benzene and styrene. Antitumor activities of the metal complexes along with ligands have been studied on Dalton lymphoma (DL) and 2PK3 murine lymphoma cells.

Nanoparticles for hematologic diseases detection and treatment

Nanotechnology, as an interdisciplinary science, combines engineering, physics, material sciences, and chemistry with the biomedicine knowhow, trying the management of a wide range of diseases. Nanoparticle-based devices holding tumor imaging, targeting and therapy capabilities are formerly under study. Since conventional hematological therapies are sometimes defined by reduced selectivity, low therapeutic efficacy and many side effects, in this review we discuss the potential advantages of the NPs' use in alternative/combined strategies. In the introduction the basic notion of nanomedicine and nanoparticles' classification are described, while in the main text nanodiagnostics, nanotherapeutics and theranostics solutions coming out from the use of a wide-ranging NPs availability are listed and discussed.

Azouracil and Its Cu(II)-Catalyzed Cyclization to an Anticancer Active Triazole Derivative: Symmetrical and Asymmetrical Reductive Cleavage, DNA Interaction, and Molecular Docking Studies

The 6-amino-1,3-dimethyl uracil-based azo derivative (p-carboxy phenylazouracil, L11) undergoes Cu(II)-catalyzed cyclization to a triazole derivative, namely, 1,3-dimethyl-8-(p-carboxy phenyl) azapurine (L11P). Interestingly, the azo functionality of L11 undergoes both symmetrical and asymmetrical reductive cleavage at two different reaction conditions. The chloride salts of Mn(II), Ni(II), and Pd(II) catalyze reductive cleavage of an azo moiety in an asymmetric manner, producing a new uracil hydrazine derivative (A3). On the other hand, hydrazine catalyzes symmetrical reductive cleavage of the azo moiety of L11, resulting in 5,6-diamino-1,3-dimethyl uracil (A2) along with the starting p-aminobenzoic acid (A1). Time-dependent density functional theoretical (TD-DFT) studies provide optimized geometries of L11, L11P, and A3 along with their orbital energies. The L11 and L11P bind firmly to genomic DNA of E. coli with a site size n ∼ 9 and n ∼ 8. The L11P shows anticancer activity on selected murine lymphoma cancer cell lines (DL, YAC1, and 2PK3). In addition, its antiproliferative activity is measured with several cancer cell lines and found hemocompatible toward blood cells. Corresponding molecular docking studies of L11P with caspase-3 (cysteine-aspartic proteases) unlock their mode of interaction.

Functionalized mesoporous silica nanoparticles and biomedical applications

Since the first report in early 1990s, mesoporous silica nanoparticles (MSNs) have progressively attracted the attention of scientists due to their potential applications in physic, energy storage, imaging, and especially in biomedical engineering. Owning the unique physiochemical properties, such as highly porosity, large surface area and pore volume, functionalizable, tunable pore and particle sizes and biocompatibility, and high loading cavity, MSNs offer efficient encapsulation and then controlled release, and in some cases, intracellular delivery of bioactive molecules for biomedical applications. During the last decade, functionalized MSNs that show respond upon the surrounding stimulus changes, such as temperature, pH, redox, light, ultrasound, magnetic or electric fields, enzyme, redox, ROS, glucose, and ATP, or their combinations, have continuously revolutionized their potential applications in biomedical engineering. Therefore, this review focuses on discussion the recent fabrication of functionalized MSNs and their potential applications in drug delivery, therapeutic treatments, diagnostic imaging, and biocatalyst. In addition, some potential clinical applications and challenges will also be discussed.