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The adenosine triphosphate (ATP)-binding cassette (ABC) importer GlnPQ from Lactococcus lactishas two sequential covalently linked substrate-binding domains (SBDs), which capture the substrates and deliver them to the translocon. The two SBDs differ in their ligand specificities, binding affinities and the distance to the transmembrane domain; interestingly, both SBDs can bind their ligands simultaneously without affecting each other. In this work, we studied the binding of ligands to both SBDs using X-ray crystallography and molecular dynamics simulations. We report three high-resolution structures of SBD1, namely, the wild-type SBD1 with bound asparagine or arginine, and E184D SBD1 with glutamine bound. Molecular dynamics (MD) simulations provide a detailed insight into the dynamics associated with open-closed transitions of the SBDs.

Here we describe the early stages of a fragment-based lead discovery (FBLD) project for a recently elucidated synthetic lethal target, the PRMT5/MTA complex, for the treatment of MTAP-deleted cancers. Starting with five fragment/PRMT5/MTA X-ray co-crystal structures, we employed a two-phase fragment elaboration process encompassing optimization of fragment hits and subsequent fragment growth to increase potency, assess synthetic tractability, and enable structure-based drug design. Two lead series were identified, one of which led to the discovery of the clinical candidate MRTX1719.

Photopharmacology addresses the challenge of drug selectivity and side effects through creation of photoresponsive molecules activated with light with high spatiotemporal precision. This is achieved through incorporation of molecular photoswitches and photocages into the pharmacophore. However, the structural basis for the light-induced modulation of inhibitory potency in general is still missing, which poses a major design challenge for this emerging field of research. Here we solved crystal structures of the glutamate transporter homologue GltTkin complex with photoresponsive transport inhibitors—azobenzene derivative of TBOA (both in transand cisconfiguration) and with the photocaged compound ONB-hydroxyaspartate. The essential role of glutamate transporters in the functioning of the central nervous system renders them potential therapeutic targets in the treatment of neurodegenerative diseases. The obtained structures provide a clear structural insight into the origins of photocontrol in photopharmacology and lay the foundation for application of photocontrolled ligands to study the transporter dynamics by using time-resolved X-ray crystallography.

In recent years, the concept of formation of a sufficiently autonomous cytokine network in a malignant tumour has emerged. In this regard, the data on the role of this network and its signalling pathways in the process of metastasis are an interesting topic. The aim of this study was to evaluate the in vitro cytokine-producing potential of mammary adenocarcinoma (MAC; and cells of its microenvironment) from patients with or without metastases in regional lymph nodes (LNs). By enzyme-linked immunosorbent assays of culture supernatants, we studied the cytokine production by biopsy samples of MAC: spontaneous and stimulated by polyclonal activators (PAs: phytohaemagglutinin, concanavalin A and lipopolysaccharide). The levels of spontaneous production of interleukin (IL)-10 and granulocyte colony-stimulating factor (G-CSF) and the amounts of IL-2, IL-10, G-CSF and monocyte chemoattractant protein-1 (MCP-1) produced during stimulation by PAs, as well as the index of stimulation by polyclonal activators (ISPA) for IL-2 production, were lower for MAC with LN metastasis than for MAC without LN metastasis. The levels of spontaneous production of IL-2 and interferon (IFN)-γ and the ISPA for granulocyte–macrophage colony-stimulating factor (GM-CSF) production were higher for MAC with LN metastasis. There were only three pairwise correlations between the produced cytokines that were specific to MAC with LN metastasis: IL-2 and IFN-γ, IL-6 and GM-CSF, and IL-8 and GM-CSF. There were 10 pairwise correlations between the produced cytokines that were specific to nonmetastasising MAC: IL-6 and IL-10, IL-6 and MCP-1, IL-8 and IL-10, IL-8 and MCP-1, IL-10 and G-CSF, IL-10 and MCP-1, IFN-γ and MCP-1, MCP-1 and G-CSF, G-CSF and IL-1Ra, and GM-CSF and tumour necrosis factor (TNF)-α. Our data indicate that metastatic tumours show desynchronisation of many pathways of induction and synthesis of cytokines that are characteristic of nonmetastatic tumours.

Objective: The aim of this study was to evaluate the relationship between cytokine production, GM-CSF receptor (CSF2RA), and IL-1 receptor (IL1R2) expression in mammary adenocarcinoma and their association with it histopathological parameters and lymph node metastasis.Methods: We analyzed tumor biopsy samples (cultured in vitro) from 50 women (aged 43-75) with invasive ductal mammary adenocarcinomas. Enzyme-linked immunosorbent assay method the concentrations of interleukin 2, interleukin 6, interleukin 8, interleukin 10, interleukin 17, interleukin 18, interleukin 1β, interleukin 1Ra, tumor necrosis factor α, interferon γ, granulocyte colony-stimulating factor, granulocyte macrophage colony-stimulating factor, and vascular endothelial growth factor A were determined in culture supernatants. The expression of CSF2RA and IL1R2 in tumor biopsy was evaluated by immunohistochemical method.Results: We showed that the “cytokine profile” of a tumor (the ability of tumor cells and its microenvironment to produce different cytokines) is very individual. It has been shown that the features of the cytokine profile of the mammary adenocarcinoma are important for the formation and realization of the metastatic potential of the mammary adenocarcinoma. We found correlations between some histopathological parameters of mammary adenocarcinoma and coefficients KGM-CSF/CSF2RAand KIL-1β/IL1R2, which are the ratios of concentrations of granulocyte macrophage colony-stimulating factor and interleukin -1β to expression of CSF2RA and IL1R2, respectively. KGM-CSF/CSF2RApositively correlated with highly differentiated cells, and KIL-1β/IL1R2positively correlated with the number of mitoses, poorly differentiated cells, and a number of lymph nodes with metastases. KGM-CSF/CSF2RApositively correlated with the concentrations of interleukin 6, interleukin 8, interleukin 1Ra, and granulocyte colony-stimulating factor. KIL-1β/IL1R2positively correlated with concentrations of interleukin 1β and interferon γ and negative correlated with the concentrations of vascular endothelial growth factor A and tumor necrosis factor α. It is shown that KIL-1β/IL1R2can be considered as a prognostic indicator predicting the probability of mammary adenocarcinoma metastasis to regional lymph nodes.Conclusions: The ratios of granulocyte macrophage colony-stimulating factor and interleukin 1β cytokines, produced in tumor, to the expression of CSF2RA and IL1R2 depend on levels of interleukin 6, interleukin 8, tumor necrosis factor α, interferon γ, granulocyte colony-stimulating factor, and vascular endothelial growth factor A and are important factors affecting the progression and metastasis of the breast cancer.

Currently, the role of cytokines in the tumor progression, including breast cancer, is universally recognized. At the same time, there are still many questions concerning the role of individual cytokines and receptors for cytokines in various morphogenetic processes underlying the tumor progression. The objective of this work was to study cytokine production and vascular endothelial growth factor (VEGF)-R2 and VEGF-R1 expression by mammary adenocarcinoma (MAC) and the correlations with histopathological parameters of malignant tumors. The object of the study was cultured tumor biopsy samples from 47 women aged 43–75 years with invasive ductal carcinoma, which was classified as grade II–III adenocarcinoma. It was shown that the cytokine profiles of the supernatants of MAC samples from patients differ greatly. A correlation between the levels of VEGF-R2 and tumor necrosis factor (TNF)-R1 expression was observed. Correlations were also revealed during analysis of the relations of histopathological MAC indicators with KVEGF-R2/VEGF-Aand KTNF-R1/TNF-αcoefficients, which are equal, respectively, to the ratio of expression values of receptors VEGF-R2 and TNF-R1 to the concentrations of the relevant cytokines (VEGF-A and TNF-α) in the culture supernatants of the same MAC samples. A direct correlation was identified between KVEGF-R/VEGF-Aand some histopathological MAC characteristics: proportion of cells undergoing mitosis or pathological mitosis in MAC and poorly differentiated cells. KVEGF-R2/VEGF-Adirectly correlated with the concentration in supernatant interleukin (IL)-18 and interferon (IFN)-γ. KTNF-R1/TNF-αwas inversely correlated with the concentration in supernatant of IL-1Ra, IL-8, and granulocyte-macrophage colony-stimulating factor (GM-CSF). The data obtained show that the high-level production of IL-18 and IL-1β by MAC, overexpression of VEGF-R2 in tumor (at relatively low VEGF-A production), and the high level of IFN-γ production are attributed factors contributing to the formation of a population of low-grade cells in the tumor. The factors regulating the population of moderately differentiated cells in the tumor are referred to as IL-1Ra, IL-8, and GM-CSF.