Synthesis and Characterization of Folic Acid-Functionalized DPLA-co-PEG Nanomicelles for the Targeted Delivery of Letrozole.

An effective treatment for hormone-dependent breast cancer is chemotherapy using cytotoxic agents such as letrozole (LTZ). However, most anticancer drugs, including LTZ, are classified as class IV biopharmaceuticals, which are associated with low water solubility, poor bioavailability, and significant toxicity. As a result, developing a targeted delivery system for LTZ is critical for overcoming these challenges and limitations. Here, biodegradable LTZ-loaded nanocarriers were synthesized by solvent emulsification evaporation using nanomicelles prepared with dodecanol-polylactic acid-co-polyethylene glycol (DPLA-co-PEG). Furthermore, cancer cell-targeting folic acid (FA) was conjugated into the nanomicelles to achieve a more effective and safer cancer treatment. During our investigation, DPLA-co-PEG and DPLA-co-PEG-FA displayed a uniform and spherical morphology. The average diameters of DPLA-co-PEG and DPLA-co-PEG-FA nanomicelles were 86.5 and 241.3 nm, respectively. Our preliminary data suggest that both nanoformulations were cytocompatible, with ≥90% cell viability across all concentrations tested. In addition, the amphiphilic nature of the nanomicelles led to high drug loading and dispersion in water, resulting in the extended release of LTZ for up to 50 h. According to the Higuchi model, nanomicelles functionalized with FA have a greater potential for the controlled delivery of LTZ into target cells. This model was confirmed experimentally, as LTZ-containing DPLA-co-PEG-FA was significantly and specifically more cytotoxic (up to 90% cell death) toward MCF-7 cells, a hormone-dependent human breast cancer cell line, when compared to free LTZ and LTZ-containing DPLA-co-PEG. Furthermore, a half-maximal inhibitory concentration (IC50) of 87 ± 1 nM was achieved when MCF-7 cells were exposed to LTZ-containing DPLA-co-PEG-FA, whereas higher doses of 125 ± 2 and 100 ± 2 nM were required for free LTZ and LTZ-containing DPLA-co-PEG, respectively. Collectively, DPLA-co-PEG-FA represents a promising nanosized drug delivery system to target controllably the delivery of drugs such as chemotherapeutics.

Newly Developed Targeted Therapies Against the Androgen Receptor in Triple-Negative Breast Cancer: A Review.

Among different types of breast cancers (BC), triple-negative BC (TNBC) amounts to 15% to 20% of breast malignancies. Three principal characteristics of TNBC cells are (i) extreme aggressiveness, (ii) absence of hormones, and (iii) growth factor receptors. Due to the lack or poor expression of the estrogen receptor, human epidermal growth factor receptor 2, and progesterone receptor, TNBC is resistant to hormones and endocrine therapies. Consequently, chemotherapy is currently used as the primary approach against TNBC. Expression of androgen receptor (AR) in carcinoma cells has been observed in a subset of patients with TNBC; therefore, inhibiting androgen signaling pathways holds promise for TNBC targeting. The new AR inhibitors have opened up new therapy possibilities for BC patients carrying AR-positive TNBC cells. Our group provides a comprehensive review of the structure and function of the AR and clinical evidence for targeting the cell's nuclear receptor in TNBC. We updated AR agonists, inhibitors, and antagonists. We also presented a new era of genetic manipulating CRISPR/Cas9 and nanotechnology as state-of-the-art approaches against AR to promote the efficiency of targeted therapy in TNBC. SIGNIFICANCE STATEMENT: The lack of effective treatment for triple-negative breast cancer is a health challenge. The main disadvantages of existing treatments are their side effects, due to their nonspecific targeting. Molecular targeting of cellular receptors, such as androgen receptors, increased expression in malignant tissues, significantly improving the survival rate of breast cancer patients.

Nanoparticles as Powerful Tools for Crossing the Blood-brain Barrier.

The blood-brain barrier (BBB) is considered an important protective barrier in the central nervous system (CNS). The barrier is mainly formed by endothelial cells (ECs) interconnected by various junctions such as tight junctions (TJs), gap junctions, and adherent junctions. They collectively constitute an intensive barrier to the transit of different substances into the brain, selectively permitting small molecules to pass through by passive movement but holding off large ones such as peptides and proteins to cross the brain. Hence some molecules selectively transfer across the BBB by active routes via transcytosis. The BBB also forms a barrier against neurotoxins as well as pathogenic agents. Although various CNS disorders like Alzheimer's disease (AD) and Parkinson's disease (PD) could hamper the integrity of the border. Nevertheless, the BBB acts as a barrier for CNS disorders treatment because it prevents the drugs from reaching their target in the CNS. In recent years, different strategies, including osmotic disruption of BBB or chemical modification of drugs, have been used to transfer the chemotherapeutic agents into brain substances. Nowadays, nanoparticles (NPs) have been used as an effective and non-invasive tool for drug delivery and diagnosis of CNS disorders. In this review, we discuss the structural characteristic of BBB, safe passageways to cross the BBB, and the relation of barrier lesions with different CNS disorders. In the end, we explore the progress in drug delivery, diagnosis, imaging, and treatment of CNS disorders using nanoparticles.

Structural evolution of Delta lineage of SARS-CoV-2.

One of the main obstacles in prevention and treatment of COVID-19 is the rapid evolution of the SARS-CoV-2 Spike protein. Given that Spike is the main target of common treatments of COVID-19, mutations occurring at this virulent factor can affect the effectiveness of treatments. The B.1.617.2 lineage of SARS-CoV-2, being characterized by many Spike mutations inside and outside of its receptor-binding domain (RBD), shows high infectivity and relative resistance to existing cures. Here, utilizing a wide range of computational biology approaches, such as immunoinformatics, molecular dynamics (MD), analysis of intrinsically disordered regions (IDRs), protein-protein interaction analyses, residue scanning, and free energy calculations, we examine the structural and biological attributes of the B.1.617.2 Spike protein. Furthermore, the antibody design protocol of Rosetta was implemented for evaluation the stability and affinity improvement of the Bamlanivimab (LY-CoV55) antibody, which is not capable of interactions with the B.1.617.2 Spike. We observed that the detected mutations in the Spike of the B1.617.2 variant of concern can cause extensive structural changes compatible with the described variation in immunogenicity, secondary and tertiary structure, oligomerization potency, Furin cleavability, and drug targetability. Compared to the Spike of Wuhan lineage, the B.1.617.2 Spike is more stable and binds to the Angiotensin-converting enzyme 2 (ACE2) with higher affinity.

Combination of androgen receptor inhibitor enzalutamide with the CDK4/6 inhibitor ribociclib in triple negative breast cancer cells.

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer (BC) that currently lacks specific therapy options. Thus, chemotherapy continues to be the primary treatment, and developing novel targets is a top clinical focus. The androgen receptor (AR) has emerged as a therapeutic target in a subtype of TNBC, with substantial clinical benefits shown in various clinical studies. Numerous studies have shown that cancer is associated with changes in components of the cell cycle machinery. Although cell cycle cyclin-dependent kinase (CDK) 4/6 inhibitors are successful in the treatment of ER-positive BC, they are not helpful in the treatment of patients with TNBC. We investigated the possibility of combining CDK4/6 inhibitor(ribociclib) with AR inhibitor(enzalutamide) in the AR-positive TNBC cell line. Ribociclib showed an inhibitory effect in TNBC cells. Additionally, we found that enzalutamide reduced cell migration/invasion, clonogenic capacity, cell cycle progression, and cell growth in AR-positive cells. Enzalutamide therapy could increase the cytostatic impact of ribociclib in AR+ TNBC cells. Furthermore, dual inhibition of AR and CDK4/6 demonstrated synergy in an AR+ TNBC model compared to each treatment alone.

SARS-CoV-2 spike evolutionary behaviors; simulation of N501Y mutation outcomes in terms of immunogenicity and structural characteristic.

Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a large number of mutations in its genome have been reported. Some of the mutations occur in noncoding regions without affecting the pathobiology of the virus, while mutations in coding regions are significant. One of the regions where a mutation can occur, affecting the function of the virus is at the receptor-binding domain (RBD) of the spike protein. RBD interacts with angiotensin-converting enzyme 2 (ACE2) and facilitates the entry of the virus into the host cells. There is a lot of focus on RBD mutations, especially the displacement of N501Y which is observed in the UK/Kent, South Africa, and Brazilian lineages of SARS-CoV-2. Our group utilizes computational biology approaches such as immunoinformatics, protein-protein interaction analysis, molecular dynamics, free energy computation, and tertiary structure analysis to disclose the consequences of N501Y mutation at the molecular level. Surprisingly, we discovered that this mutation reduces the immunogenicity of the spike protein; also, displacement of Asn with Tyr reduces protein compactness and significantly increases the stability of the spike protein and its affinity to ACE2. Moreover, following the N501Y mutation secondary structure and folding of the spike protein changed dramatically.

Evaluation the Anti-Cancer Effect of PEGylated Nano-Niosomal Gingerol, on Breast Cancer Cell lines (T47D), In-Vitro

Background: Cancer is a significant problem in modern medicine, also is the most common cause of death after cardiovascular diseases, and in need of targeted drug release. Although, chemotherapy is an important candidate in cancer treatment, but it has many side effects on healthy tissues of the body. Therefore, Nano technology is used for specific function, by the least side effects and damage to normal cells. Materials and method: In this study, the pharmacological properties of PEGylated Nano-niosomal Gingerol was examined. Noisome were prepared using reverse phase evaporation method, which contains specific proportion of cholesterol, span60 and polyethylene glycol. Then, PEGylated the prepared formulation by PEG6600. The amount of release and encapsulation of the drug was investigated. The percentage of remains of cancer cell line T47D treated with PEGylated niosomal Gingerol. Results: The average diameter of the nanoparticles, size distribution and zeta potential were reported for PEGylated niosomal sample 35.65 nm, 0.17 and 21 mv, and for PEGylated niosomal drug sample 256.9 nm, 0.23 and 28 mv, respectively. The amount of OD for encapsulated drug was 0.198, also the amount of concentration of the drug which is not encapsulated, was 0.77947 µl of the drug per ml. This value of encapsulated drug was 76.38 percent. Conclusion: The results showed that IC50 of the formulation of PEGylated nanoniosomal Gingerol is less than the standard drug. It seems, the cause of this phenomenon is due to the effect of Polyethylene glycol, in more stability and slower drug release, in the formulation of PEGylated niosome. Also, Polyethylene glycol makes increase in the drug dealing and its greater influence with the target cell. In this study, more than 76% of the Gingerol drug in PEGylated nanoniosomal formulation were enclose. Also, we could reduce the amount of drug release, as much as possible.

General Characteristics and Cytotoxic Effects of Nano-Poly (Butyl Cyanoacrylate) Containing Carboplatin on Ovarian Cancer Cells

The initial response to treatment and subsequent development of resistance to carboplatin are very important challenges. Use of nano drug delivery is a new method to replace standard chemotherapy. In this research, both non-PEGylated and PEGylated nanoparticles (NPs) were prepared by mini-emulsion polymerization of poly (butyl cyanoacrylate) (PBCA) NPs. Characteristics such as size, polydispersity index (PDI), zeta potential, drug release, and stability were examined. In addition, infrared spectroscopy was used for description of the produced NPs. Then, cytotoxicity effects of both formulations were studied on the A2780CIS ovarian cancer cell line with incubation for 24, 48, and 72h. Examination of characteristics of loaded carboplatin on the PBCA NPs under suitable laboratory conditions showed a positive effect of PEG on their properties. Cytotoxicity studies demonstrated greater toxicity with both formulations of nano-drugs than the free drug. The results indicated that PBCA NPs can be considered as suitable candidates for nano-drugs in chemotherapy.