Molecular mechanism underlying the selective attack of trehalose lipids on cancer cells as revealed by coarse-grained molecular dynamics simulations

Nullomer peptide increases immune cell infiltration and reduces tumor metabolism in triple negative breast cancer mouse model

Background

Nullomers are the shortest strings of absent amino acid (aa) sequences in a species or group of species. Primes are those nullomers that have not been detected in the genome of any species. 9S1R is a 5-aa peptide derived from a prime sequence that is tagged with 5 arginine aa, used to treat triple negative breast cancer (TNBC) in an in vivo TNBC mouse model. 9S1R is administered in trehalose (9S1R-NulloPT), which enhances solubility and exhibits some independent effects against tumor growth and is thus an important component in the drug preparation.

Method

We examined the effect of 9S1R-NulloPT on tumor growth, metabolism, metastatic burden, necrosis, tumor immune microenvironment, and the transcriptome of aggressive mouse TNBC tumors.

Results

The peptide-treated mice had smaller tumors in the initial phase of the treatment, as compared to the untreated control, and reduced in vivo bioluminescence at later stages, which is indicative of metabolically inactive tumors. A decrease in ex vivo bioluminescence was also observed in the excised tumors of treated mice, but not in the secondary metastasis in the lungs. The treatment also caused changes in tumor immune microenvironment with increased infiltration of immune cells and margin inflammation. The treatment upregulated 365 genes and downregulated 710 genes in tumors compared to the untreated group. Consistent with in vitro findings in breast cancer cell lines, downregulated genes in the treated TNBC tumors include Cellular Metabolic Process Related genes (179), specifically mitochondrial genes associated with TCA cycle/oxidative phosphorylation (44), and translation machinery/ribosome biogenesis genes (45). Among upregulated genes, the Developmental Pathway (13), ECM Organization (12) and Focal Adhesion Related Pathways (7) were noteworthy. We also present data from a pilot study using a bilateral BC mouse model, which supports our findings.

Conclusion

In conclusion, although 9S1R-NulloPT was moderate at reducing the tumor volume, it altered the tumor immune microenvironment as well as the tumor transcriptome, rendering tumors metabolically less active by downregulating the mitochondrial function and ribosome biogenesis. This corroborates previously published in vitro findings.

Aqueous Sugar-Based Amphiphile Systems: Recent Advances in Phase Behavior and Nanoarchitectonics

Currently, numerous fascinating molecular assemblies are used in food, cosmetics, and pharmaceuticals. Sugar-based amphiphiles are representative constituents of these molecular assemblies. Despite numerous studies on these generic compounds, many aspects remain unexplored even in aqueous systems. In this review, molecular assembly studies of sugar-based amphiphiles in aqueous systems are summarized. First, recent advances in molecular assembly studies, including the glassy state of lyotropic and thermotropic liquid crystalline (LC) phases, modulated crystal phases, and coagels consisting of nanofibers of alkyl β-D-glycosides, are presented. Second, research on thermotropic LC phases under desiccated conditions of trehalose fatty acid monoesters to clarify the fundamental behaviors of the glassy state and their use as stabilizers of glass-forming surfactants for pharmaceutical applications are discussed. Several effective X-ray analytical approaches are included to identify or clarify these phenomena, unknown or unsolved for a long time. Third, a comprehensive analysis of vitamin E (tocopherol)-cyclodextrin in aqueous systems is presented. Along with these topics, the importance of investigating stabilizer-free functional components, considered minor components, is highlighted. These unveiled phenomena or concepts will contribute to the development of nanoarchitectonics covering the self-assembly and selforganization of soft molecules.

Phase Behaviour, Functionality, and Physicochemical Characteristics of Glycolipid Surfactants of Microbial Origin

Growing demand for biosurfactants as environmentally friendly counterparts of chemically derived surfactants enhances the extensive search for surface-active compounds of biological (microbial) origin. The understanding of the physicochemical properties of biosurfactants such as surface tension reduction, dispersion, emulsifying, foaming or micelle formation is essential for the successful application of biosurfactants in many branches of industry. Glycolipids, which belong to the class of low molecular weight surfactants are currently gaining a lot of interest for industrial applications. For this reason, we focus mainly on this class of biosurfactants with particular emphasis on rhamnolipids and sophorolipids, the most studied of the glycolipids.