Evidence for shared genetic risk factors between lymphangioleiomyomatosis and pulmonary function

Lymphangioleiomyomatosis; Risk factors; Pulmonary functionLinfangioleiomiomatosis; Factores de riesgo; Función pulmonarLimfangioleiomiomatosi; Factors de risc; Funció pulmonarIntroduction Lymphangioleiomyomatosis (LAM) is a rare low-grade metastasising disease characterised by cystic lung destruction. The genetic basis of LAM remains incompletely determined, and the disease cell-of-origin is uncertain. We analysed the possibility of a shared genetic basis between LAM and cancer, and LAM and pulmonary function. Methods The results of genome-wide association studies of LAM, 17 cancer types and spirometry measures (forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio and peak expiratory flow (PEF)) were analysed for genetic correlations, shared genetic variants and causality. Genomic and transcriptomic data were examined, and immunodetection assays were performed to evaluate pleiotropic genes. Results There were no significant overall genetic correlations between LAM and cancer, but LAM correlated negatively with FVC and PEF, and a trend in the same direction was observed for FEV1. 22 shared genetic variants were uncovered between LAM and pulmonary function, while seven shared variants were identified between LAM and cancer. The LAM-pulmonary function shared genetics identified four pleiotropic genes previously recognised in LAM single-cell transcriptomes: ADAM12, BNC2, NR2F2 and SP5. We had previously associated NR2F2 variants with LAM, and we identified its functional partner NR3C1 as another pleotropic factor. NR3C1 expression was confirmed in LAM lung lesions. Another candidate pleiotropic factor, CNTN2, was found more abundant in plasma of LAM patients than that of healthy women. Conclusions This study suggests the existence of a common genetic aetiology between LAM and pulmonary function

Heterogeneity and Cancer-Related Features in Lymphangioleiomyomatosis Cells and Tissue

Lymphangioleiomyomatosis (LAM) is a rare, low-grade metastasizing disease characterized by cystic lung destruction. LAM can exhibit extensive heterogeneity at the molecular, cellular, and tissue levels. However, the molecular similarities and differences among LAM cells and tissue, and their connection to cancer features are not fully understood. By integrating complementary gene and protein LAM signatures, and single-cell and bulk tissue transcriptome profiles, we show sources of disease heterogeneity, and how they correspond to cancer molecular portraits. Subsets of LAM diseased cells differ with respect to gene expression profiles related to hormones, metabolism, proliferation, and stemness. Phenotypic diseased cell differences are identified by evaluating lumican (LUM) proteoglycan and YB1 transcription factor expression in LAM lung lesions. The RUNX1 and IRF1 transcription factors are predicted to regulate LAM cell signatures, and both regulators are expressed in LAM lung lesions, with differences between spindle-like and epithelioid LAM cells. The cancer single-cell transcriptome profiles most similar to those of LAM cells include a breast cancer mesenchymal cell model and lines derived from pleural mesotheliomas. Heterogeneity is also found in LAM lung tissue, where it is mainly determined by immune system factors. Variable expression of the multifunctional innate immunity protein LCN2 is linked to disease heterogeneity. This protein is found to be more abundant in blood plasma from LAM patients than from healthy women.This research was partially supported by AELAM (ICO-IDIBELL agreement, to M.A. Pujana), The LAM Foundation Seed Grant 2019, to M.A. Pujana, Carlos III Institute of Health grant PI18/01029, to M.A. Pujana and ICI19/00047 to M. Molina-Molina [co-funded by European Regional Development Fund (ERDF), a way to build Europe], Generalitat de Catalunya SGR grant 2017-449, to M.A. Pujana, the CERCA Program for IDIBELL institutional support, and ZonMW-TopZorg grant 842002003, to C.H.M. van Moorsel. M. Plass was supported by a “Ramón y Cajal” contract of the Spanish Ministry of Science and Innovation (RYC2018-024564-I) and J. Moss was supported by the Intramural Research Program of NIH/NHLBI

Modification of BRCA1-associated breast cancer risk by HMMR overexpression

Breast cancer risk for carriers of BRCA1 pathological variants is modified by genetic factors. Genetic variation in HMMR may contribute to this effect. However, the impact of risk modifiers on cancer biology remains undetermined and the biological basis of increased risk is poorly understood. Here, we depict an interplay of molecular, cellular, and tissue microenvironment alterations that increase BRCA1-associated breast cancer risk. Analysis of genome-wide association results suggests that diverse biological processes, including links to BRCA1-HMMR profiles, influence risk. HMMR overexpression in mouse mammary epithelium increases Brca1-mutant tumorigenesis by modulating the cancer cell phenotype and tumor microenvironment. Elevated HMMR activates AURKA and reduces ARPC2 localization in the mitotic cell cortex, which is correlated with micronucleation and activation of cGAS-STING and non-canonical NF-kappa B signaling. The initial tumorigenic events are genomic instability, epithelial-to-mesenchymal transition, and tissue infiltration of tumor-associated macrophages. The findings reveal a biological foundation for increased risk of BRCA1-associated breast cancer. The effect of hyaluronan-mediated motility receptor (HMMR) expression in BRCA1-associated breast cancer risk remains unknown. Here, HMMR overexpression induces the activation of cGAS-STING and non-canonical NF-kappa B signalling, instigating an immune permissive environment for breast cancer development

Immune Cell Associations with Cancer Risk.

Proper immune system function hinders cancer development, but little is known about whether genetic variants linked to cancer risk alter immune cells. Here, we report 57 cancer risk loci associated with differences in immune and/or stromal cell contents in the corresponding tissue. Predicted target genes show expression and regulatory associations with immune features. Polygenic risk scores also reveal associations with immune and/or stromal cell contents, and breast cancer scores show consistent results in normal and tumor tissue. SH2B3 links peripheral alterations of several immune cell types to the risk of this malignancy. Pleiotropic SH2B3 variants are associated with breast cancer risk in BRCA1/2 mutation carriers. A retrospective case-cohort study indicates a positive association between blood counts of basophils, leukocytes, and monocytes and age at breast cancer diagnosis. These findings broaden our knowledge of the role of the immune system in cancer and highlight promising prevention strategies for individuals at high risk

Elucidation of the Mode of Action of a New Antibacterial Compound Active against Staphylococcus aureus and Pseudomonas aeruginosa.

Nosocomial and community-acquired infections caused by multidrug resistant bacteria represent a major human health problem. Thus, there is an urgent need for the development of antibiotics with new modes of action. In this study, we investigated the antibacterial characteristics and mode of action of a new antimicrobial compound, SPI031 (N-alkylated 3, 6-dihalogenocarbazol 1-(sec-butylamino)-3-(3,6-dichloro-9H-carbazol-9-yl)propan-2-ol), which was previously identified in our group. This compound exhibits broad-spectrum antibacterial activity, including activity against the human pathogens Staphylococcus aureus and Pseudomonas aeruginosa. We found that SPI031 has rapid bactericidal activity (7-log reduction within 30 min at 4x MIC) and that the frequency of resistance development against SPI031 is low. To elucidate the mode of action of SPI031, we performed a macromolecular synthesis assay, which showed that SPI031 causes non-specific inhibition of macromolecular biosynthesis pathways. Liposome leakage and membrane permeability studies revealed that SPI031 rapidly exerts membrane damage, which is likely the primary cause of its antibacterial activity. These findings were supported by a mutational analysis of SPI031-resistant mutants, a transcriptome analysis and the identification of transposon mutants with altered sensitivity to the compound. In conclusion, our results show that SPI031 exerts its antimicrobial activity by causing membrane damage, making it an interesting starting point for the development of new antibacterial therapies

MAGT1 deficiency: Novel insights into a controversial protein with a key role in N-glycosylation

Congenital Disorders of Glycosylation (CDG) are a rapidly growing and heterogeneous group of rare metabolic diseases caused by inborn defects in glycosylation. The latter is an important posttranslational modification process of proteins and lipids. Over 50% of the proteome is glycosylated and the sugar moieties (or glycans) are essential for mediating a protein's function and stability. N-glycosylation of proteins is the major form of glycosylation and is characterized by the addition of glycan chains on the asparagine (Asn, N) residue of nascent proteins by the oligosaccharyltransferase (OST) complex. Patients with CDG show a very variable phenotype, with severe developmental delay and multi-organ failure, accompanied by neurologic symptoms and dysmorphic features. The lab recently identified candidate genes through either targeted-NGS (Next Generation Sequencing) or WES (Whole Exome Sequencing), for which the pathogenicity of the identified variants needs to be confirmed. One of those candidates is the X-linked gene MAGT1. Over the years MAGT1 has been swayed back and forth between a role as a subunit of the OST complex in the endoplasmic reticulum or as a plasma membrane localised Mg2+ transporter. We hypothesize that MAGT1 is part of the OST-complex and that one of the substrates could be an Mg2+ transporter. Assays to interrogate the (hypo)glycosylation of target proteins, the localisation of the protein, the pathogenicity of the mutations and to quantify the Mg2+ levels, etc. will be performed. Second, Whole Genome Sequencing (WGS) will be used to solve our 'unsolvable' cases, which allows us to explore the full mutational spectrum of the patients. In total 20 patients of our 'unsolvable' cohort were selected for further analysis. These patients represent clinical phenotypes that were not previously described in CDG and/or are from nuclear families with multiple affected siblings. Although they were exhaustively tested using enzymatic studies and NGS (WES or a targeted panel), no enzymatic alterations nor candidate mutations were found. With this approach, the ambition is to find new CDG genes or new types of mutations, so far never associated with CDG.status: publishe

Heterogeneity and Cancer-Related Features in Lymphangioleiomyomatosis Cells and Tissue.

Lymphangioleiomyomatosis (LAM) is a rare, low-grade metastasizing disease characterized by cystic lung destruction. LAM can exhibit extensive heterogeneity at the molecular, cellular, and tissue levels. However, the molecular similarities and differences among LAM cells and tissue, and their connection to cancer features are not fully understood. By integrating complementary gene and protein LAM signatures, and single-cell and bulk tissue transcriptome profiles, we show sources of disease heterogeneity, and how they correspond to cancer molecular portraits. Subsets of LAM diseased cells differ with respect to gene expression profiles related to hormones, metabolism, proliferation, and stemness. Phenotypic diseased cell differences are identified by evaluating LUM proteoglycan and YB1 transcription factor expression in LAM lung lesions. The RUNX1 and IRF1 transcription factors are predicted to regulate LAM cell signatures, and both regulators are expressed in LAM lung lesions, with differences between spindle-like and epithelioid LAM cells. The cancer single-cell transcriptome profiles most similar to those of LAM cells include a breast cancer mesenchymal cell model and lines derived from pleural mesotheliomas. Heterogeneity is also found in LAM lung tissue, where it is mainly determined by immune system factors. Variable expression of the multifunctional innate immunity protein LCN2 is linked to disease heterogeneity. This protein is found to be more abundant in blood plasma from LAM patients than from healthy women.pre-print3262 K

Mutations in MAGT1 lead to a glycosylation disorder with a variable phenotype

International audienc

Mutations in MAGT1 lead to a glycosylation disorder with a variable phenotype

Congenital disorders of glycosylation (CDG) are a group of rare metabolic diseases, due to impaired protein and lipid glycosylation. We identified two patients with defective serum transferrin glycosylation and mutations in the MAGT1 gene. These patients present with a phenotype that is mainly characterized by intellectual and developmental disability. MAGT1 has been described to be a subunit of the oligosaccharyltransferase (OST) complex and more specifically of the STT3B complex. However, it was also claimed that MAGT1 is a magnesium (Mg2+) transporter. So far, patients with mutations in MAGT1 were linked to a primary immunodeficiency, characterized by chronic EBV infections attributed to a Mg2+ homeostasis defect (XMEN). We compared the clinical and cellular phenotype of our two patients to that of an XMEN patient that we recently identified. All three patients have an N-glycosylation defect, as was shown by the study of different substrates, such as GLUT1 and SHBG, demonstrating that the posttranslational glycosylation carried out by the STT3B complex is dysfunctional in all three patients. Moreover, MAGT1 deficiency is associated with an enhanced expression of TUSC3, the homolog protein of MAGT1, pointing toward a compensatory mechanism. Hence, we delineate MAGT1-CDG as a disorder associated with two different clinical phenotypes caused by defects in glycosylation.status: publishe

Tumour DDR1 promotes collagen fibre alignment to instigate immune exclusion

Immune exclusion predicts poor patient outcomes in multiple malignancies, including triple-negative breast cancer (TNBC)1. The extracellular matrix (ECM) contributes to immune exclusion2. However, strategies to reduce ECM abundance are largely ineffective or generate undesired outcomes3,4. Here we show that discoidin domain receptor 1 (DDR1), a collagen receptor with tyrosine kinase activity5, instigates immune exclusion by promoting collagen fibre alignment. Ablation of Ddr1 in tumours promotes the intratumoral penetration of T cells and obliterates tumour growth in mouse models of TNBC. Supporting this finding, in human TNBC the expression of DDR1 negatively correlates with the intratumoral abundance of anti-tumour T cells. The DDR1 extracellular domain (DDR1-ECD), but not its intracellular kinase domain, is required for immune exclusion. Membrane-untethered DDR1-ECD is sufficient to rescue the growth of Ddr1-knockout tumours in immunocompetent hosts. Mechanistically, the binding of DDR1-ECD to collagen enforces aligned collagen fibres and obstructs immune infiltration. ECD-neutralizing antibodies disrupt collagen fibre alignment, mitigate immune exclusion and inhibit tumour growth in immunocompetent hosts. Together, our findings identify a mechanism for immune exclusion and suggest an immunotherapeutic target for increasing immune accessibility through reconfiguration of the tumour ECM