Marine edible macroalgae have functional proprieties that might improve human health and wellbeing. Lipids represent a minor fraction of macroalgae, yet with major interest as main carriers of omega 3 polyunsaturated fatty acids and intrinsic bioactive properties. In this study, we used lipid extracts from the green macroalgae Ulva rigida and Codium tomentosum; the red Gracilaria gracilis,Palmaria palmata and Porphyra dioica; and the brown Fucus vesiculosus, produced in a land-based integrated multitrophic aquaculture (IMTA) system. We determined the lipid quality indices based on their fatty acid profiles and their bioactivities as putative antioxidant, anti-inflammatory and antiproliferative agents. The results reveal to be species-specific, namely U. rigida displayed the lowest atherogenicity and thrombogenicity indices. Palmaria palmata and F. vesiculosus lipid extracts displayed the lowest inhibitory concentration in the free radical scavenging antioxidant assays. Ulva rigida, C. tomentosum, P. palmata and P. dioica inhibited COX-2 activity by up to 80%, while P. dioica and P. palmata extracts showed the highest cytotoxic potential in the MDA-MB-231 breast cancer cells. This work enhances the valorization of macroalgae as functional foods and promising ingredients for sustainable and healthy diets and fosters new applications of high-valued algal biomass, in a species-specific context.

Regulation of gene expression includes the replacement of canonical histones for non-allelic histone variants, as well as their multiple targeting by postranslational modifications. H2A variants are highly conserved between species suggesting they execute important functions that cannot be accomplished by canonical histones. Altered expression of many H2A variants is associated to cancer. MacroH2A variants are enriched in heterocromatic foci and are necessary for chromatin condensation. MacroH2A1.1 and macroH2A1.2 are two mutually exclusive isoforms. MacroH2A1.1 and macroH2A2 inhibit proliferation and are associated with better cancer prognosis; while macroH2A1.2 is associated to cancer progression. H2AX variant functions as a sensor of DNA damage and defines the cellular response towards DNA repair or apoptosis; therefore, screening approaches and therapeutic options targeting H2AX have been proposed. H2A.Z is enriched in euchromatin, acting as a proto-oncogene with established roles in hormone responsive cancers and overexpressed in endocrine-resistant disease. Other H2A family members have also been found altered in cancer, but their function remains unknown. Substantial progress has been made to understand histone H2A variants, their contribution to normal cellular function and to cancer development and progression. Yet, implementation of high resolution mass spectrometry is needed to further our knowledge on highly homologous H2A variants expression and function.

Progression to hormone‐independent growth leading to endocrine therapy resistance occurs in a high proportion of patients with estrogen receptor alpha (ERα) and progesterone receptors (PR) positive breast cancer. We and others have previously shown that estrogen‐ and progestin‐induced tumor growth requires ERα and PR interaction at their target genes. Here, we show that fibroblast growth factor 2 (FGF2)‐induces cell proliferation and tumor growth through hormone‐independent ERα and PR activation and their interaction at the MYC enhancer and proximal promoter. MYC inhibitors, antiestrogens or antiprogestins reverted FGF2‐induced effects. LC–MS/MS identified 700 canonical proteins recruited to MYC regulatory sequences after FGF2 stimulation, 397 of which required active ERα (ERα‐dependent). We identified ERα‐dependent proteins regulating transcription that, after FGF2 treatment, were recruited to the enhancer as well as proteins involved in transcription initiation that were recruited to the proximal promoter. Also, among the ERα‐dependent and independent proteins detected at both sites, PR isoforms A and B as well as the novel protein product PRBΔ4 were found. PRBΔ4 lacks the hormone‐binding domain and was able to induce reporter gene expression from estrogen‐regulated elements and to increase cell proliferation when cells were stimulated with FGF2 but not by progestins. Analysis of the Cancer Genome Atlas data set revealed that PRBΔ4 expression is associated with worse overall survival in luminal breast cancer patients. This discovery provides a new mechanism by which growth factor signaling can engage nonclassical hormone receptor isoforms such as PRBΔ4, which interacts with growth‐factor activated ERα and PR to stimulate MYC gene expression and hence progression to endocrine resistance.

No abstract

Porphyrins are promising materials for photodynamic therapy, but their low solubility and aggregation in biological environments are still obstacles to surpass. In order to overcome these limitations, the conjugation of porphyrins with graphene quantum dots (GQDs), here functioning as a vehicle to improve the internalization of porphyrins by cancer cells, was considered. The GQDs were conjugated with an aminoporphyrin via amide linkage using both thionyl chloride (SOCl2) and 1-ethyl-3-(3′-dimethylaminopropyl)­carbodiimide coupling methodologies. Based on structural characterization (Fourier transform infrared and X-ray photoelectron spectroscopy), the best porphyrin loading was observed with the SOCl2 procedure. The new hybrids were investigated as phototherapeutic agents in high incidence breast cancer (T-47D cell line) under white light, and a significant photocytotoxic effect was observed at 10 nM. The conjugation of GQDs to the aminoporphyrin promoted an efficient uptake by the T-47D cells when compared with the nonimmobilized porphyrin. These results point out the high potential of the new hybrids to be explored as theragnostic agents.

No abstract

Histone–lysine N-methyltransferase SETD7 regulates a variety of cancer-related processes, in a tissue-type and signalling context-dependent manner. To date, there is no consensus regarding SETD7´s biological functions, or potential for cancer diagnostics and therapeutics. In this work, we summarised the literature on SETD7 expression and function in cancer, to identify the contexts where SETD7 expression and targeting can lead to improvements in cancer diagnosis and therapy. The most studied cancers were found to be lung and osteosarcoma followed by colorectal and breast cancers. SETD7 mRNA and/or protein expression in human cancer tissue was evaluated using public databases and/or in-house cohorts, but its prognostic significance remains inconclusive. The most studied cancer-related processes regulated by SETD7 were cell proliferation, apoptosis, epithelial-mesenchymal transition, migration and invasion with special relevance to the pRb/E2F-1 pathway. SETD7 consistently prevented epithelial to mesenchymal transition in different cancer types, and inhibition of its function appears to be associated with improved response to DNA-damaging agents in most of the analysed studies. Stabilising mutations in SETD7 target proteins prevent their methylation or promote other competing post-translational modifications that can override the SETD7 effect. This indicates that a clear discrimination of these mutations and competing signalling pathways must be considered in future functional studies.

Patient-derived cellular models are a powerful approach to study human disease, especially neurodegenerative diseases, such as Parkinson's disease, where affected primary neurons, e.g., substantia nigra dopaminergic neurons, are almost inaccessible. Starting with a comprehensive generic reconstruction of human metabolism, Recon3D, we generated a high-quality, constraint-based, genome-scale, in silico model of human dopaminergic neuronal metabolism (iDopaNeuro1). It is a synthesis of extensive manual curation of the biochemical literature on neuronal metabolism, together with novel, quantitative, transcriptomic and targeted exometabolomic data from human stem cell-derived, midbrain-specific, dopaminergic neurons in vitro. Thermodynamic constraint-based modelling with iDopaNeuro1 is qualitatively accurate (92% correct) and quantitatively accurate (Spearman rank 0.7) at predicting metabolite secretion or uptake, given quantitative exometabolomic constraints on uptakes, or secretions, respectively. iDopaNeuro1 is also qualitatively accurate at predicting the consequences of metabolic perturbations, e.g., complex I inhibition (Spearman rank 0.69) in a manner consistent with literature on monogenic mitochondrial Parkinson's disease. The iDopaNeuro1 model provides a foundation for a quantitative systems biochemistry approach to metabolic dysfunction in Parkinson's disease. Moreover, the plethora of novel mathematical and computational approaches required to develop it are generalisable to study any other disease associated with metabolic dysfunction.