Comparative Molecular Immunological Activity of Physiological Metal Oxide Nanoparticle and its Anticancer Peptide and RNA Complexes

Nickel nanoparticles induce autophagy and apoptosis via HIF-1α/mTOR signaling in human bronchial epithelial cells

With the rapid development of nanotechnology, the potential adverse health effects of nanoparticles have been caught more attention and become global concerns. However, the underlying mechanisms in metal nanoparticle-induced toxic effects are still largely obscure. In this study, we investigated whether exposure to nickel nanoparticles (Nano-Ni) and titanium dioxide nanoparticles (Nano-TiO₂) would alter autophagy and apoptosis levels in normal human bronchial epithelial BEAS-2B cells and the underlying mechanisms involved in this process. Our results showed that the expressions of autophagy- and apoptosis-associated proteins were dysregulated in cells exposed to Nano-Ni. However, exposure to the same doses of Nano-TiO₂ had no significant effects on these proteins. In addition, exposure to Nano-Ni, but not Nano-TiO₂, led to nuclear accumulation of HIF-1α and decreased phosphorylation of mTOR in BEAS-2B cells. Inhibition of HIF-1α by CAY10585 abolished Nano-Ni-induced decreased phosphorylation of mTOR, while activation of mTOR by MHY1485 did not affect Nano-Ni-induced nuclear accumulation of HIF-1α. Furthermore, both HIF-1α inhibition and mTOR activation abolished Nano-Ni-induced autophagy but enhanced Nano-Ni-induced apoptosis. Blockage of autophagic flux by Bafilomycin A1 exacerbated Nano-Ni-induced apoptosis, while activation of autophagy by Rapamycin effectively rescued Nano-Ni-induced apoptosis. In conclusion, our results demonstrated that Nano-Ni exposure caused increased levels of autophagy and apoptosis via the HIF-1α/mTOR signaling axis. Nano-Ni-induced autophagy has a protective role against Nano-Ni-induced apoptosis. These findings provide us with further insight into Nano-Ni-induced toxicity.

Current Understanding of Flavonoids in Cancer Therapy and Prevention

Cancer is a major cause of death worldwide, with multiple pathophysiological manifestations. In particular, genetic abnormalities, inflammation, bad eating habits, radiation exposure, work stress, and toxin consumption have been linked to cancer disease development and progression. Recently, natural bioactive chemicals known as polyphenols found in plants were shown to have anticancer capabilities, destroying altered or malignant cells without harming normal cells. Flavonoids have demonstrated antioxidant, antiviral, anticancer, and anti-inflammatory effects. Flavonoid type, bioavailability, and possible method of action determine these biological actions. These low-cost pharmaceutical components have significant biological activities and are beneficial for several chronic disorders, including cancer. Recent research has focused primarily on isolating, synthesizing, and studying the effects of flavonoids on human health. Here we have attempted to summarize our current knowledge of flavonoids, focusing on their mode of action to better understand their effects on cancer.

Single-helical formyl β-glucan effectively deliver CpG DNA with poly(dA) to macrophages for enhanced vaccine effects

Single helical β-glucan is a one-dimensional host that can form a hybrid helix with DNAs/RNAs as delivery systems. However, unmodified β-glucan has a gelling tendency and a single helical conformation is challenging to obtain. Therefore, in this study, we developed a β-glucan formyl derivative with stable single helical conformation and no gelling tendency. Circular dichroism studies found that the formyl-β-glucan could form a hybrid helix with DNA CpG-poly(dA). The hybrid helix delivery system showed improved activation on antigen-presenting cells, thereby upregulating the mRNA and protein levels of inflammatory factors, and had an immune-enhancing effect on ovalbumin (OVA) immunized mice. These results indicate that formyl-β-glucan can be developed as a non-cationic supramolecular DNA delivery platform with low toxicity and high efficiency.

Advances of Cobalt Nanomaterials as Anti-Infection Agents, Drug Carriers, and Immunomodulators for Potential Infectious Disease Treatment

Infectious diseases remain the most serious public health issue, which requires the development of more effective strategies for infectious control. As a kind of ultra-trace element, cobalt is essential to the metabolism of different organisms. In recent decades, nanotechnology has attracted increasing attention worldwide due to its wide application in different areas, including medicine. Based on the important biological roles of cobalt, cobalt nanomaterials have recently been widely developed for their attractive biomedical applications. With advantages such as low costs in preparation, hypotoxicity, photothermal conversion abilities, and high drug loading ability, cobalt nanomaterials have been proven to show promising potential in anticancer and anti-infection treatment. In this review, we summarize the characters of cobalt nanomaterials, followed by the advances in their biological functions and mechanisms. More importantly, we emphatically discuss the potential of cobalt nanomaterials as anti-infectious agents, drug carriers, and immunomodulators for anti-infection treatments, which might be helpful to facilitate progress in future research of anti-infection therapy.

Renovation as innovation: Repurposing human antibacterial peptide LL-37 for cancer therapy

In many organisms, antimicrobial peptides (AMPs) display wide activities in innate host defense against microbial pathogens. Mammalian AMPs include the cathelicidin and defensin families. LL37 is the only one member of the cathelicidin family of host defense peptides expressed in humans. Since its discovery, it has become clear that they have pleiotropic effects. In addition to its antibacterial properties, many studies have shown that LL37 is also involved in a wide variety of biological activities, including tissue repair, inflammatory responses, hemotaxis, and chemokine induction. Moreover, recent studies suggest that LL37 exhibits the intricate and contradictory effects in promoting or inhibiting tumor growth. Indeed, an increasing amount of evidence suggests that human LL37 including its fragments and analogs shows anticancer effects on many kinds of cancer cell lines, although LL37 is also involved in cancer progression. Focusing on recent information, in this review, we explore and summarize how LL37 contributes to anticancer effect as well as discuss the strategies to enhance delivery of this peptide and selectivity for cancer cells.

Inspirations of Cobalt Oxide Nanoparticle Based Anticancer Therapeutics

Cobalt is essential to the metabolism of all animals due to its key role in cobalamin, also known as vitamin B12, the primary biological reservoir of cobalt as an ultra-trace element. Current cancer treatment strategies, including chemotherapy and radiotherapy, have been seriously restricted by their side effects and low efficiency for a long time, which urges us to develop new technologies for more effective and much safer anticancer therapies. Novel nanotechnologies, based on different kinds of functional nanomaterials, have been proved to act as effective and promising strategies for anticancer treatment. Based on the important biological roles of cobalt, cobalt oxide nanoparticles (NPs) have been widely developed for their attractive biomedical applications, especially their potential for anticancer treatments due to their selective inhibition of cancer cells. Thus, more and more attention has been attracted to the preparation, characterization and anticancer investigation of cobalt oxide nanoparticles in recent years, which is expected to introduce novel anticancer treatment strategies. In this review, we summarize the synthesis methods of cobalt oxide nanoparticles to discuss the advantages and restrictions for their preparation. Moreover, we emphatically discuss the anticancer functions of cobalt oxide nanoparticles as well as their underlying mechanisms to promote the development of cobalt oxide nanoparticles for anticancer treatments, which might finally benefit the current anticancer therapeutics based on functional cobalt oxide nanoparticles.

Designing of Co0.5Ni0.5GaxFe2-xO4 (0.0 ≤ x ≤ 1.0) Microspheres via Hydrothermal Approach and Their Selective Inhibition on the Growth of Cancerous and Fungal Cells

The current study offers an efficient design of novel nanoparticle microspheres (MCs) using a hydrothermal approach. The Co_0.5Ni_0.5Ga_xFe_2−xO₄ (0.0 ≤ x ≤ 1.0) MCs were prepared by engineering the elements, such as cobalt (Co), nickel (Ni), iron (Fe), and gallium (Ga). There was a significant variation in MCs’ physical structure and surface morphology, which was evaluated using energy dispersive X-ray analysis (EDX), X-ray diffractometer (XRD), high-resolution transmission electron microscopy (HR-TEM), and scanning electron microscope (SEM). The anti-proliferative activity of MCs was examined by MTT assay and DAPI staining using human colorectal carcinoma cells (HCT-116), human cervical cancer cells (HeLa), and a non-cancerous cell line—human embryonic kidney cells (HEK-293). Post 72 h treatment, MCs caused a dose dependent inhibition of growth and proliferation of HCT-116 and HeLa cells. Conversely, no cytotoxic effect was observed on HEK-293 cells. The anti-fungal action was assessed by the colony forming units (CFU) technique and SEM, resulting in the survival rate of Candida albicans as 20%, with severe morphogenesis, on treatment with MCs x = 1.0. These findings suggest that newly engineered microspheres have the potential for pharmaceutical importance, in terms of infectious diseases and anti-cancer therapy.

Cobalt oxide nanoparticle-synergized protein degradation and phototherapy for enhanced anticancer therapeutics

How to enable protein degradation pathways including the autophagy-lysosome pathway (ALP) and the ubiquitin-proteasome system (UPS) to enhance the efficacy of anticancer treatments remains a substantial challenge. Cobalt oxide nanoparticles (Co₃O₄ NPs) have attracted interest in recent years for their potential use as a synergistic anticancer treatment, although their therapeutic mechanisms of action are still poorly understood. Here, we describe the synergistic use of Co₃O₄ NPs as an autophagy inhibitor, chemosensitizer and photosensitizer, which manipulate protein degradation pathways (ALP and UPS) and photothermal therapy for enhanced anticancer treatments both in vitro and in vivo. We show that Co₃O₄ NPs can induce autolysosome accumulation and lysosomal functions damage by inhibiting lysosomal proteolytic activity and reducing intracellular ATP levels. Notably, Co₃O₄ NPs can be combined with the proteasome inhibitor, Carfilzomib (Cfz), to promote the accumulation of autophagic substrates, protein ubiquitination, and endoplasmic reticulum stress, and in doing so, inhibit cancer progression. By taking advantage of their photothermal conversion efficiency, Co₃O₄ NPs can also serve as photothermal sensitizer, which synergistically enhances the anticancer efficacy of Cfz both in vitro and in vivo. In summary, we provide evidence of a nanomaterial-synergized, photothermal anticancer strategy that synergistically targets cancer cell survival pathways and may eventually serve to enhance the anticancer efficacy of established cancer therapeutics.