Utilizing G2/M retention effect to enhance tumor accumulation of active targeting nanoparticles

Artificial Space Weathering to Mimic Solar Wind Enhances the Toxicity of Lunar Dust Simulants in Human Lung Cells

During NASA's Apollo missions, inhalation of dust particles from lunar regolith was identified as a potential occupational hazard for astronauts. These fine particles adhered tightly to spacesuits and were unavoidably brought into the living areas of the spacecraft. Apollo astronauts reported that exposure to the dust caused intense respiratory and ocular irritation. This problem is a potential challenge for the Artemis Program, which aims to return humans to the Moon for extended stays in this decade. Since lunar dust is "weathered" by space radiation, solar wind, and the incessant bombardment of micrometeorites, we investigated whether treatment of lunar regolith simulants to mimic space weathering enhanced their toxicity. Two such simulants were employed in this research, Lunar Mare Simulant-1 (LMS-1), and Lunar Highlands Simulant-1 (LHS-1), which were added to cultures of human lung epithelial cells (A549) to simulate lung exposure to the dusts. In addition to pulverization, previously shown to increase dust toxicity sharply, the simulants were exposed to hydrogen gas at high temperature as a proxy for solar wind exposure. This treatment further increased the toxicity of both simulants, as measured by the disruption of mitochondrial function, and damage to DNA both in mitochondria and in the nucleus. By testing the effects of supplementing the cells with an antioxidant (N-acetylcysteine), we showed that a substantial component of this toxicity arises from free radicals. It remains to be determined to what extent the radicals arise from the dust itself, as opposed to their active generation by inflammatory processes in the treated cells.

Predicting anti-cancer drug combination responses with a temporal cell state network model

Cancer chemotherapy combines multiple drugs, but predicting the effects of drug combinations on cancer cell proliferation remains challenging, even for simple in vitro systems. We hypothesized that by combining knowledge of single drug dose responses and cell state transition network dynamics, we could predict how a population of cancer cells will respond to drug combinations. We tested this hypothesis here using three targeted inhibitors of different cell cycle states in two different cell lines in vitro. We formulated a Markov model to capture temporal cell state transitions between different cell cycle phases, with single drug data constraining how drug doses affect transition rates. This model was able to predict the landscape of all three different pairwise drug combinations across all dose ranges for both cell lines with no additional data. While further application to different cell lines, more drugs, additional cell state networks, and more complex co-culture or in vivo systems remain, this work demonstrates how currently available or attainable information could be sufficient for prediction of drug combination response for single cell lines in vitro.

Alfaleh M, H. Abdulaal W, Bakhaidar RB, Alselami MO, Zahrani MAL, Alqarni HM, F. Alghaith A, Alshehri S, Badr-Eldin SM, Aldawsari HM, Al-hejaili OD, Aldhabi BM, Mahdi WA. Wasp venom peptide improves the proapoptotic activity of alendronate sodium in A549 lung cancer cells

BACKGROUND

Lung cancer in men and women is considered the leading cause for cancer-related mortality worldwide. Anti-cancer peptides represent a potential untapped reservoir of effective cancer therapy.

METHODOLOGY

Box-Behnken response surface design was applied for formulating Alendronate sodium (ALS)-mastoparan peptide (MP) nanoconjugates using Design-Expert software. The optimization process aimed at minimizing the size of the prepared ALS-MP nanoconjugates. ALS-MP nanoconjugates' particle size, encapsulation efficiency and the release profile were determined. Cytotoxicity, cell cycle, annexin V staining and caspase 3 analyses on A549 cells were carried out for the optimized formula.

RESULTS

The results revealed that the optimized formula was of 134.91±5.1 nm particle size. The novel ALS-MP demonstrated the lowest IC50 (1.3 ± 0.34 μM) in comparison to ALS-Raw (37.6 ± 1.79 μM). Thus, the results indicated that when optimized ALS-MP nanoconjugate was used, the IC50 of ALS was also reduced by half. Cell cycle analysis demonstrated a significantly higher percentage of cells in the G2-M phase following the treatment with optimized ALS-MP nanoconjugates.

CONCLUSION

The optimized ALS-MP formula had significantly improved the parameters related to the cytotoxic activity towards A549 cells, compared to control, MP and ALS-Raw.

Preparation of Liposomal Raloxifene-Graphene Nanosheet and Evaluation of Its In Vitro Anticancer Effects

BACKGROUND

In current years, researchers have shown their prime interest in developing multifunctional drug delivery systems, especially against cancers, for effective anticancer outcomes.

METHODOLOGY

Raloxifene (RLX) loaded liposomal-graphene nanosheet (GNS) was developed. The novelty of this work was to enhance the solubilization of RLX and improvement of its bioavailability in the disease area. So, the selection of optimized formula design of experiment was implemented which produced the desired formula with the particle size of 156.333 nm. Further, encapsulation efficiency, in vitro release, and thermodynamic stability of optimized formulation were evaluated. The optimized formulation exhibited prolonged release of RLX for a longer period of 24 h, which can minimize the dose-related toxicity of the drug. Furthermore, optimized formulation demonstrated remarkable thermodynamic stability in terms of phase separation, creaming, and cracking.

RESULTS

The cytotoxicity study on the A549 cell line exhibited significant (P < .05) results in favor of optimized formulation than the free drug. The apoptotic activity was carried out by Annexin V staining and Caspase 3 analysis, which demonstrated remarkable promising results for optimized liposomal formulation.

CONCLUSION

From the findings of the study, it can be concluded that the novel optimized liposomal formulation could be pondered as a novel approach for the treatment of lung cancer.

Protein corona: Dr. Jekyll and Mr. Hyde of nanomedicine

Nanomedicine is an interdisciplinary field of research, comprising science, engineering, and medicine. Many are the clinical applications of nanomedicine, such as molecular imaging, medical diagnostics, targeted therapy, and image-guided surgery. Despite major advances during the past 20 years, many efforts must be done to understand the complex behavior of nanoparticles (NPs) under physiological conditions, the kinetic and thermodynamic principles, involved in the rational design of NP. Once administrated in physiological environment, NPs interact with biomolecules and they are surrounded by protein corona (PC) or biocorona. PC can trigger an immune response, affecting NPs toxicity and targeting capacity. This review aims to provide a detailed description of biocorona and of parameters that are able to control PC formation and composition. Indeed, the review provides an overview about the role of PC in the modulation of both cytotoxicity and immune response as well as in the control of targeting capacity.

Enhanced Internalization of Nanoparticles Following Ionizing Radiation Leads to Mitotic Catastrophe in MG-63 Human Osteosarcoma Cells

This study aims to investigate whether ionizing radiation combined with doxorubicin-conjugated iron oxide nanoparticles (NP-DOX) improves the internalization and cytotoxic effects of the nano-carrier-mediated drug delivery in MG-63 human osteosarcoma cells. NP-DOX was designed and synthesized using the co-precipitation method. Highly stable and crystalline nanoparticles conjugated with DOX were internalized in MG-63 cells through macropinocytosis and located in the perinuclear area. Higher nanoparticles internalization in MG-63 cells previously exposed to 1 Gy X-rays was correlated with an early accumulation of cells in G₂/M, starting at 12 h after treatment. After 48 h, the application of the combined treatment led to higher cytotoxic effects compared to the individual treatment, with a reduction in the metabolic capacity and unrepaired DNA breaks, whilst a low percent of arrested cells, contributing to the commitment of mitotic catastrophe. NP-DOX showed hemocompatibility and no systemic cytotoxicity, nor histopathological alteration of the main organs.

Vorinostat-loaded titanium oxide nanoparticles (anatase) induce G2/M cell cycle arrest in breast cancer cells via PALB2 upregulation

Breast cancer is a group of diseases in which cells divide out of controlled, typically resulting in a mass. Erlotinib is targeted cancer drug which functions as an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase. It is used mainly to treat of non-small cell lung cancer patients and has an action against pancreatic cancer. Vorinostat (aka suberanilohydroxamic acid) is an inhibitor of histone deacetylases (HDAC), which has an epigenetic modulation activity. It is used to treat cutaneous T cell lymphoma. In the present study, the erlotinib (ERL) and vorinostat (SAHA) loaded TiO₂ nanoparticles (NPs) were used for the treatment of the breast cancer cells (MDA-MB-231 and MCF-7) and human cancerous amniotic cells (WISH). Cell count and viability were negatively affected in all treatments compared to normal cells and bare TiO₂ NPs. Apoptosis results indicated a significant increase in the total apoptosis in all treatments compared with control cells. ERL- and SAHA-loaded TiO₂ NPs treatments arrested breast cancer cells at G2/M phase, which indicate the cytotoxic effect of these treatment. Partner and localizer of BRCA2 (PALB2) gene expression was assessed using qPCR. The results indicate that PLAB2 was upregulated in ERL- and SAHA-loaded TiO₂ NPs compared with control cells and can be used as nanocarrier for chemotherapy drugs. However, this conclusion necessitates further confirmative investigation.

Thymoquinone-Loaded Soy-Phospholipid-Based Phytosomes Exhibit Anticancer Potential against Human Lung Cancer Cells

Thymoquinone (TQ), a natural polyphenol, has been associated with various pharmacological responses; however, low bioavailability of TQ limits its clinical application. Thus, a novel phytosomal delivery system of TQ-Phospholipon® 90H complex (TQ-phytosome) was developed by refluxing combined with anti-solvent precipitation. This TQ delivery system was optimized by a three-factor, three-level Box-Behnken design. The optimized TQ-phytosome size was (45.59 ± 1.82 nm) and the vesicle size was confirmed by transmission electron microscopy. The in vitro release pattern of the formulation indicated a biphasic release pattern, where an initial burst release was observed within 2 h, followed by a prolonged release. A remarkable increase in dose-dependent cytotoxicity was evident from the significant decrease in IC50 value of TQ-phytosomes (4.31 ± 2.21 µM) against the A549 cell line. The differential effect of TQ-phytosomes in cell cycle analysis was observed, where cancer cells were accumulated on G2-M and pre-G1 phases. Furthermore, increased apoptotic induction and cell necrosis of TQ-phytosomes were revealed with the annexin V staining technique via activation of caspase-3. In reactive oxygen species (ROS) analysis, TQ-phytosomes acted to significantly increase ROS generation in A549 cells. In conclusion, the sustained release profile with significantly-improved anticancer potential could be obtained with TQ by this phytosomal nanocarrier platform.

Optimized Icariin Phytosomes Exhibit Enhanced Cytotoxicity and Apoptosis-Inducing Activities in Ovarian Cancer Cells

Icariin (ICA) is a flavonol glycoside that has pleiotropic pharmacological actions. It has cytotoxic effects against ovarian cancer cells and increases their chemosensitivity to chemotherapeutic drugs. Phytosomes are identified for their potential in drug delivery of cytotoxic agents. Thus, the purpose of this study was to determine the potential enhancement of ICA cytotoxicity activity in OVCAR-3 ovarian cancer cells via its formulation in phytosomes. ICA-phytosomal formulation was optimized using a Box-Behnken design. Particle size, shape, and in vitro drug release were used to characterize the optimized formula. The optimized formulation exhibited enhanced in vitro drug release. ICA-phytosomes exhibited enhanced cytotoxicity against ovarian cancer cells. Cell cycle analysis indicated accumulation of cells challenged with ICA-phytosomes in G2/M and pre-G1 phases. Staining of cells with annexin V indicated significant elevation of percentage cells with early and late apoptosis as well as total cell death. In addition, the formulation significantly disturbed mitochondrial membrane potential and cellular content of caspase 3. In addition, intracellular release of reactive oxygen species (ROS) was enhanced by ICA-phytosomes. In conclusion, phytosome formulation of ICA significantly potentiates its cytotoxic activities against OVCAR-3 cells. This is mediated, at least partly, by enhanced ICA cellular permeation, apoptosis, and ROS.

Effects of carbon dots surface functionalities on cellular behaviors - Mechanistic exploration for opportunities in manipulating uptake and translocation

Carbon dots (CDots) for their excellent optical and other properties have been widely pursued for potential biomedical applications, in which a more comprehensive understanding on the cellular behaviors and mechanisms of CDots is required. For such a purpose, two kinds of CDots with surface passivation by 3-ethoxypropylamine (EPA-CDots) and oligomeric polyethylenimine (PEI-CDots) were selected for evaluations on their uptakes by human cervical carcinoma HeLa cells at three cell cycle phases (G₀/G₁, S and G₂/M), and on their different internalization pathways and translocations in cells. The results show that HeLa cells could internalize both CDots by different pathways, with an overall slightly higher internalization efficiency for PEI-CDots. The presence of serum in culture media could have major effects, significantly enhancing the cellular uptake of EPA-CDots, yet markedly inhibiting that of PEI-CDots. The HeLa cells at different cell cycle phases have different behaviors in taking up the CDots, which are also affected by the different dot surface moieties and serum in culture media. Mechanistic implications of the results and the opportunities associated with an improved understanding on the cellular behaviors of CDots for potentially the manipulation and control of their cellular uptakes and translocations are discussed.

A size switchable nanoplatform for targeting the tumor microenvironment and deep tumor penetration

The complex tumor microenvironment (TME) in solid tumors forms physiological barriers to the efficient delivery of nanomedicine, leading to limited therapeutic efficacy. Herein, to overcome these physiological barriers and improve the therapeutic effect, we constructed a novel size-adjustable nanoplatform for efficient drug delivery into solid tumors. The smart size-switchable nanoplatform (DGL/DOX@PP) was prepared by conjugating small dendrigraft poly-l-lysine (DGL) to poly(ethylene glycol)-poly(caprolactone) micelles via a matrix metalloproteinase 2 (MMP-2)-sensitive peptide. DGL/DOX@PP had an initial size of 100 nm and a nearly neutral charge, rendering the system able to take advantage of the enhanced permeability and retention effect. After extravasation from the tumor vessels, small DGL/DOX nanoparticles (∼30 nm) were rapidly released from DGL/DOX@PP in response to MMP-2 in the TME. This process of particle size alteration greatly enhanced the nanoparticle penetration into both multicellular spheroids (MCSs) and solid tumors. In vivo results demonstrated that compared with small and non-switchable nanoparticles, particles from the size-switchable nanoplatform achieved excellent antitumor efficacy in 4T1 tumor-bearing mice. This size-adjustable nanoplatform provides a multifunctional strategy for TME modulation and tumor penetration.

Mitochondria chaperone GRP75 moonlighting as a cell cycle controller to derail endocytosis provides an opportunity for nanomicrosphere intracellular delivery

Understanding how cancer cells regulate endocytosis during the cell cycle could lead us to capitalize this event pharmacologically. Although certain endocytosis pathways are attenuated during mitosis, the endocytosis shift and regulation during the cell cycle have not been well clarified. The conventional concept of glucose-regulated proteins (GRPs) as protein folding chaperones was updated by discoveries that translocated GRPs assume moonlighting functions that modify the immune response, regulate viral release, and control intracellular trafficking. In this study, GRP75, a mitochondria matrix chaperone, was discovered to be highly expressed in mitotic cancer cells. Using synchronized cell models and the GRP75 gene knockdown and ectopic overexpression strategy, we showed that: (1) clathrin-mediated endocytosis (CME) was inhibited whereas clathrin-independent endocytosis (CIE) was unchanged or even up-regulated in the cell cycle M-phase; (2) GRP75 inhibited CME but promoted CIE in the M-phase, which is largely due to its high expression in cancer cell mitochondria; (3) GRP75 targeting by its small molecular inhibitor MKT-077 enhanced cell cycle G1 phase-privileged CME, which provides an opportunity for intracellular delivery of nanomicrospheres sized from 40 nm to 100 nm. Together, our results revealed that GRP75 moonlights as a cell cycle controller and endocytosis regulator in cancer cells, and thus has potential as a novel interference target for nanoparticle drugs delivery into dormant cancer cells.

Folate-mediated chemotherapy and diagnostics: An updated review and outlook

Folate receptor (FR) is highly expressed in many types of human cancers, and it has been actively studied for developing targeted chemotherapy and diagnostic agents. Tremendous efforts have been made in developing FR-targeted nanomedicines and nanoprobes and translating them into clinical applications. This article provides a concise review on the latest development of folate-mediated nanomedicines and nanoprobes for chemotherapy and diagnostics with an emphasis on in vivo applications. The cellular uptake mechanisms, pharmacokinetics (PK), administration routes and major challenges in FR-targeted nanoparticles are discussed.