Systemic lupus erythematosus therapeutic strategy: From immunotherapy to gut microbiota modulation.

Systemic lupus erythematosus (SLE) is characterized by a systemic dysfunction of the innate and adaptive immune systems, leading to an attack on healthy tissues of the body. During the development of SLE, pathogenic features, such as the formation of autoantibodies to self-nuclear antigens, caused tissue damage including necrosis and fibrosis, with an increased expression of type Ⅰ interferon (IFN) regulated genes. Treatment of lupus with immunosuppressants and glucocorticoids, which are used as the standard therapy, is not effective enough and causes side effects. As an alternative, more effective immunotherapies have been developed, including monoclonal and bispecific antibodies that target B cells, T cells, co-stimulatory molecules, cytokines or their receptors, and signaling molecules. Encouraging results have been observed in clinical trials with some of these therapies. Furthermore, a chimeric antigen receptor T cells (CAR-T) therapy has emerged as the most effective, safe, and promising treatment option for SLE, as demonstrated by successful pilot studies. Additionally, emerging evidence suggests that gut microbiota dysbiosis may play a significant role in the severity of SLE, and the use of methods to normalize the gut microbiota, particularly fecal microbiota transplantation (FMT), opens up new opportunities for effective treatment of SLE.

Anticancer therapeutic strategies for targeting mutant p53-Y220C.

The tumor suppressor p53 is a transcription factor with a powerful antitumor activity that is controlled by its negative regulator murine double minute 2 (MDM2, also termed HDM2 in humans) through a feedback mechanism. At the same time, TP53 is the most frequently mutated gene in human cancers. Mutant p53 proteins lose wild-type p53 tumor suppression functions but acquire new oncogenic properties, among which are deregulating cell proliferation, increasing chemoresistance, disrupting tissue architecture, and promoting migration, invasion and metastasis as well as several other pro-oncogenic activities. The oncogenic p53 mutation Y220C creates an extended surface crevice in the DNA-binding domain destabilizing p53 and causing its denaturation and aggregation. This cavity accommodates stabilizing small molecules that have therapeutic values. The development of suitable small-molecule stabilizers is one of the therapeutic strategies for reactivating the Y220C mutant protein. In this review, we summarize approaches that target p53-Y220C, including reactivating this mutation with small molecules that bind Y220C to the hydrophobic pocket and developing immunotherapies as the goal for the near future, which target tumor cells that express the p53-Y220C neoantigen.

Pillar[5]arene/albumin biosupramolecular systems for simultaneous native protein preservation and encapsulation of a water-soluble substrate.

The growing resistance of pathogens, bacteria, viruses, and fungi to a number of drugs has encouraged researchers to use natural and synthetic biomimetic systems to overcome this challenge. Multicomponent systems are an attractive approach for drug design and multitarget therapy. In this study, we report the assembly of a three-component (pillar[5]arene, bovine serum albumin, and methyl orange) biosupramolecular system as a potential drug delivery system. We estimated the cytotoxic activity and transfection ability of pillar[5]arene derivatives and investigated the effect of the nature of macrocycle functions (L-phenylalanine, glycine, L-alanine) on the native conformation of serum albumin in a three-component system. NMR, UV-vis, fluorescence, CD spectroscopy, DLS, and molecular docking studies were performed in order to confirm the structure and possible pillar[5]arene/bovine serum albumin/methyl orange interactions occurring during the association process. Results indicate that pillar[5]arene with L-phenylalanine fragments retains the native form of BSA to the maximum extent and forms more stable associates.

Immunotherapy Strategy for Systemic Autoimmune Diseases: Betting on CAR-T Cells and Antibodies.

Systemic autoimmune diseases (SAIDs), such as systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and rheumatoid arthritis (RA), are fully related to the unregulated innate and adaptive immune systems involved in their pathogenesis. They have similar pathogenic characteristics, including the interferon signature, loss of tolerance to self-nuclear antigens, and enhanced tissue damage like necrosis and fibrosis. Glucocorticoids and immunosuppressants, which have limited specificity and are prone to tolerance, are used as the first-line therapy. A plethora of novel immunotherapies have been developed, including monoclonal and bispecific antibodies, and other biological agents to target cellular and soluble factors involved in disease pathogenesis, such as B cells, co-stimulatory molecules, cytokines or their receptors, and signaling molecules. Many of these have shown encouraging results in clinical trials. CAR-T cell therapy is considered the most promising technique for curing autoimmune diseases, with recent successes in the treatment of SLE and SSc. Here, we overview novel therapeutic approaches based on CAR-T cells and antibodies for targeting systemic autoimmune diseases.

Aggregation, Cytotoxicity and DNA Binding in a Series of Calix[4]arene Amphiphile Containing Aminotriazole Groups.

The present work focuses on the study of the aggregation and complexing properties of calixarenes as potential DNA condensation agents for gene delivery. In the current study, 1,4-triazole derivatives of calix[4]arenes 7 and 8 containing monoammonium fragments were synthesized. The synthesized compound's structure was characterized by using various spectroscopic techniques (FTIR, HRESI MS, ¹H NMR and ¹³C NMR). The interactions between a series of calix[4]arene-containing aminotriazole groups (triazole-containing macrocycles with diethylenetriammonium fragments (3 and 4) and triazole-containing macrocycles with monoammonium fragments (7 and 8)) and calf thymus DNA were carried out via UV absorption, fluorescence spectroscopy, dynamic light scattering and zeta potential measurements. The role of the binding forces of calixarene-DNA complexes was analyzed. Photophysical and morphological studies revealed the interaction of the calixarenes 3, 4 and 8 with ct-DNA, which transformed the fibrous structure of ct-DNA to completely condensed compact structures that are 50 nm in diameter. The cytotoxic properties of calixarenes 3, 4, 7 and 8 against cancerous cells (MCF7, PC-3) as well as a healthy cell line (HSF) were investigated. Compound 4 was found to have the highest toxic effect on MCF7 breast adenocarcinoma (IC50 3.3 µM).

Decasubstituted Pillar[5]arene Derivatives Containing L-Tryptophan and L-Phenylalanine Residues: Non-Covalent Binding and Release of Fluorescein from Nanoparticles.

Sensitive systems with controlled release of drugs or diagnostic markers are attractive for solving the problems of biomedicine and antitumor therapy. In this study, new decasubstituted pillar[5]arene derivatives containing L-Tryptophan and L-Phenylalanine residues have been synthesized as pH-responsive drug nanocarriers. Fluorescein dye (Fluo) was loaded into the pillar[5]arene associates and used as a spectroscopic probe to evaluate the release in buffered solutions with pH 4.5, 7.4, and 9.2. The nature of the substituents in the pillar[5]arene structure has a huge influence on the rate of delivering. When the dye was loaded into the associates based on pillar[5]arene derivatives containing L-Tryptophan, the Fluo release occurs in the neutral (pH = 7.4) and alkaline (pH = 9.2) buffered solutions. When the dye was loaded into the associates based on pillar[5]arene with L-Phenylalanine fragments, the absence of release was observed in every pH evaluated. This happens as the result of different packing of the dye in the structure of the associate. This fact was confirmed by different fluorescence mechanisms (aggregation-caused quenching and aggregation-induced emission) and association constants. It was shown that the macrocycle with L-Phenylalanine fragments binds the dye more efficiently (lgKa = 3.92). The experimental results indicate that the pillar[5]arene derivatives with amino acids fragments have a high potential to be used as a pH-responsive drug delivery devices, especially for promoting the intracellular delivering, due to its nanometric size.

Assessment of Thermal Stability of Mutant p53 Proteins via Differential Scanning Fluorimetry.

The p53 protein is a transcription factor that preserves the integrity of the genome. The TP53 gene has inactivating mutations in about 50% of all human cancers. Some missense mutations lead to decreased thermal stability in the p53 protein, its unfolding and aggregation under physiological conditions. A general understanding of the impact of point mutations on the stability and conformation of mutant p53 is essential for the design and development of small molecules that target specific p53 mutations. In this work, we determined the thermostability properties of some of the most common mutant forms of the p53 protein-p53(R273H), p53(R248Q), p53(R248W) and p53(Y220C)-that are often considered as attractive therapeutic targets. The results showed that these missense mutations lead to destabilization of the p53 protein and a decrease in its melting temperature.