18 research outputs found
Oncolytic H-1 Parvovirus Hijacks Galectin-1 to Enter Cancer Cells
Clinical studies in glioblastoma and pancreatic carcinoma patients strongly support the further development of H-1 protoparvovirus (H-1PV)-based anticancer therapies. The identification of cellular factors involved in the H-1PV life cycle may provide the knowledge to improve H-1PV anticancer potential. Recently, we showed that sialylated laminins mediate H-1PV attachment at the cell membrane. In this study, we revealed that H-1PV also interacts at the cell surface with galectin-1 and uses this glycoprotein to enter cancer cells. Indeed, knockdown/out of LGALS1, the gene encoding galectin-1, strongly decreases the ability of H-1PV to infect and kill cancer cells. This ability is rescued by the re-introduction of LGALS1 into cancer cells. Pre-treatment with lactose, which is able to bind to galectins and modulate their cellular functions, decreased H-1PV infectivity in a dose dependent manner. In silico analysis reveals that LGALS1 is overexpressed in various tumours including glioblastoma and pancreatic carcinoma. We show by immunohistochemistry analysis of 122 glioblastoma biopsies that galectin-1 protein levels vary between tumours, with levels in recurrent glioblastoma higher than those in primary tumours or normal tissues. We also find a direct correlation between LGALS1 transcript levels and H-1PV oncolytic activity in 53 cancer cell lines from different tumour origins. Strikingly, the addition of purified galectin-1 sensitises poorly susceptible GBM cell lines to H-1PV killing activity by rescuing cell entry. Together, these findings demonstrate that galectin-1 is a crucial determinant of the H-1PV life cycle.publishedVersio
Identification of novel SHOX target genes in the developing limb using a transgenic mouse model
Deficiency of the human short stature homeobox-containing gene (SHOX) has been identified in several disorders characterized by reduced height and skeletal anomalies such as Turner syndrome, Léri-Weill dyschondrosteosis and Langer mesomelic dysplasia as well as isolated short stature. SHOX acts as a transcription factor during limb development and is expressed in chondrocytes of the growth plates. Although highly conserved in vertebrates, rodents lack a SHOX orthologue. This offers the unique opportunity to analyze the effects of human SHOX expression in transgenic mice. We have generated a mouse expressing the human SHOXa cDNA under the control of a murine Col2a1 promoter and enhancer (Tg(Col2a1-SHOX)). SHOX and marker gene expression as well as skeletal phenotypes were characterized in two transgenic lines. No significant skeletal anomalies were found in transgenic compared to wildtype mice. Quantitative and in situ hybridization analyses revealed that Tg(Col2a1-SHOX), however, affected extracellular matrix gene expression during early limb development, suggesting a role for SHOX in growth plate assembly and extracellular matrix composition during long bone development. For instance, we could show that the connective tissue growth factor gene Ctgf, a gene involved in chondrogenic and angiogenic differentiation, is transcriptionally regulated by SHOX in transgenic mice. This finding was confirmed in human NHDF and U2OS cells and chicken micromass culture, demonstrating the value of the SHOX-transgenic mouse for the characterization of SHOX-dependent genes and pathways in early limb development
The serotonin receptor 3E variant is a risk factor for female IBS-D
Irritable bowel syndrome (IBS) is a gut-brain disorder of multifactorial origin. Evidence of disturbed serotonergic function in IBS accumulated for the 5-HT receptor family. 5-HT Rs are encoded by HTR3 genes and control GI function, and peristalsis and secretion, in particular. Moreover, 5-HT R antagonists are beneficial in the treatment of diarrhea predominant IBS (IBS-D). We previously reported on functionally relevant SNPs in HTR3A c.-42C > T (rs1062613), HTR3C p.N163K (rs6766410), and HTR3E c.*76G > A (rs56109847 = rs62625044) being associated with IBS-D, and the HTR3B variant p.Y129S (rs1176744) was also described within the context of IBS. We performed a multi-center study to validate previous results and provide further evidence for the relevance of HTR3 genes in IBS pathogenesis. Therefore, genotype data of 2682 IBS patients and 9650 controls from 14 cohorts (Chile, Germany (2), Greece, Ireland, Spain, Sweden (2), the UK (3), and the USA (3)) were taken into account. Subsequent meta-analysis confirmed HTR3E c.*76G > A (rs56109847 = rs62625044) to be associated with female IBS-D (OR = 1.58; 95% CI (1.18, 2.12)). Complementary expression studies of four GI regions (jejunum, ileum, colon, sigmoid colon) of 66 IBS patients and 42 controls revealed only HTR3E to be robustly expressed. On top, HTR3E transcript levels were significantly reduced in the sigma of IBS patients (p = 0.0187); more specifically, in those diagnosed with IBS-D (p = 0.0145). In conclusion, meta-analysis confirmed rs56109847 = rs62625044 as a risk factor for female IBS-D. Expression analysis revealed reduced HTR3E levels in the sigmoid colon of IBS-D patients, which underlines the relevance of HTR3E in the pathogenesis of IBS-D. [Abstract copyright: © 2022. The Author(s).
Identification of a Major Recombination Hotspot in Patients with Short Stature and SHOX Deficiency
Human growth is influenced not only by environmental and internal factors but also by a large number of different genes. One of these genes, SHOX, is believed to play a major role in growth, since defects in this homeobox-containing gene on the sex chromosomes lead to syndromal short stature (Léri-Weill dyschondrosteosis, Langer mesomelic dysplasia, and Turner syndrome) as well as to idiopathic short stature. We have analyzed 118 unrelated patients with Léri-Weill dyschondrosteosis and >1,500 patients with idiopathic short stature for deletions encompassing SHOX. Deletions were detected in 34% of the patients with Léri-Weill dyschondrosteosis and in 2% of the patients with idiopathic short stature. For 27 patients with Léri-Weill dyschondrosteosis and for 6 with idiopathic short stature, detailed deletion mapping was performed. Analysis was performed by polymerase chain reaction with the use of pseudoautosomal polymorphic markers and by fluorescence in situ hybridization with the use of cosmid clones. Here, we show that, although the identified deletions vary in size, the vast majority (73%) of patients tested share a distinct proximal deletion breakpoint. We propose that the sequence present within this proximal deletion breakpoint “hotspot” region predisposes to recurrent breaks
Alteration of DNA binding, dimerization, and nuclear translocation of SHOX homeodomain mutations identified in idiopathic short stature and Leri-Weill dyschondrosteosis
Long-range conserved non-coding SHOX sequences regulate expression in developing chicken limb and are associated with short stature phenotypes in human patients
DataSheet_1_Treatment dependent impact of plasma-derived exosomes from head and neck cancer patients on the epithelial-to-mesenchymal transition.pdf
BackgroundEpithelial to mesenchymal transition (EMT) is a key process in carcinogenesis of head and neck squamous cell carcinoma (HNSCC), contributing to tumor invasiveness, distant metastasis, and recurrence. Exosomes are known mediators and regulators of EMT. Here, we analyze the impact of exosomes that were primed by conventional therapy on EMT modulation.MethodsPlasmas of n = 22 HNSCC patients were collected before and after standard of care surgery and adjuvant or primary (chemo)radiotherapy. Exosomes were isolated by size exclusion chromatography. Upon co-incubation of exosomes with HNSCC cells, the cellular EMT profile was analyzed by flow cytometry and RT-qPCR. Wound healing assays were performed to evaluate migratory potential of exosome-treated cells.ResultsReduction of total exosome protein after therapy and in vitro exosome induced EMT profiles were dependent on the type of treatment. Exosomal TFG-β and miRNA cargo were partly responsible for observed exosome induced EMT changes. Exosomes from recurrent patients induced higher tumor cell migration after therapy than exosomes from disease-free patients.ConclusionsHNSCC patients’ exosomes from timepoints before and after therapy were able to confer therapy induced EMT modulation in vitro and have the potential to monitor the EMT process. Exosome induced changes in migratory potential emerged as discriminants of therapy outcome.</p
Regulated genes in transgenic mice and validation of <i>Ctgf</i> as a target.
<p>(A): qRT-PCR using limb RNA (E12.5-E14.5) from wildtype (Wt) and transgenic littermates (Tg) (N = 8–10 for each stage). Measurements were carried out individually, in duplicates, and normalized to <i>Adam9</i> and <i>Sdha</i>. Relative normalized values are presented on the y-axis. Significances are indicated in each diagram by asterisks (*: <i>p</i>≤0.05, **: <i>p</i>≤0.01, ***: <i>p</i>≤0.001). Variations are indicated by the standard deviation (SD). In 7/8 candidates an upregulation was confirmed as significant in at least one embryonic stage. (B): nCounter analysis of <i>CTGF</i> and <i>SHOX</i> expression in NHDF and U2OS cells after transient transfections of <i>SHOX</i> and <i>p.Y141D</i>. <i>CTGF</i> is significantly downregulated in NHDF cells, whereas it is significantly upregulated in U2OS cells. Values on y-axis represent absolute counts of mRNA, normalized to <i>ADAM9</i>, <i>HPRT1</i> and <i>SDHA</i>. Significancies are indicated by asterisks. (C): <i>In situ</i> hybridization using a <i>Ctgf</i> antisense riboprobe on embryonic limbs from wildtype and <i>SHOX</i>-transgenic littermates (N = 8) at stage E12.5. In transgenic embryos, enhanced and distalized expression of <i>Ctgf</i> was detected in the middle part of the developing limbs.</p
miR-16 and miR-103 impact 5-HT receptor signalling and correlate with symptom profile in irritable bowel syndrome
Irritable bowel syndrome (IBS) is a gut-brain disorder involving alterations in intestinal sensitivity and motility. Serotonin 5-HT4 receptors are promising candidates in IBS pathophysiology since they regulate gut motor function and stool consistency, and targeted 5-HT4R selective drug intervention has been proven beneficial in subgroups of patients. We identified a single nucleotide polymorphism (SNP) (rs201253747) c.∗61 T > C within the 5-HT4 receptor gene HTR4 to be predominantly present in diarrhoea-IBS patients (IBS-D). It affects a binding site for the miR-16 family and miR-103/miR-107 within the isoforms HTR4b/i and putatively impairs HTR4 expression. Subsequent miRNA-profiling revealed downregulation of miR-16 and miR-103 in the jejunum of IBS-D patients correlating with symptoms. In vitro assays confirmed expression regulation via three 3′UTR binding sites. The novel isoform HTR4b-2 lacking two of the three miRNA binding sites escapes miR-16/103/107 regulation in SNP carriers. We provide the first evidence that HTR4 expression is fine-tuned by miRNAs, and that this regulation is impaired either by the SNP c.∗61 T > C or by diminished levels of miR-16 and miR-103 suggesting that HTR4 might be involved in the development of IBS-D