Η νεοπλασία των όρχεων, αν και σχετικά αποτελεί μια σπάνια μορφή νεοπλασίας (1- 2% όλων των νεοπλασμάτων του άνδρα), είναι ο πιο συχνός όγκος στις ηλικίες 20-40 ετών, αποτελώντας την τρίτη κατά σειρά αιτία θανάτου στις ηλικίες αυτές. Περίπου το 95% των όγκων όρχεων προέρχεται από τα βλαστικά κύτταρα. Η αλληλεπίδραση των κυττάρων με άλλα κύτταρα ή με συστατικά του εξωκυττάριου χώρου, καθώς και η μετακίνηση στο ενδοθήλιο των αρτηριών και στο εξωφλεβικό ιστό, είναι εξαρτημένη από την ενεργότητα των μορίων προσκόλλησης όπως οι ιντεγκρίνες, οι σελεκτίνες και μέλη της υπεροικογένειας των ανοσοσφαιρινών, καντχερίνες και ο CD44. Ο CD44 είναι μια γλυκοπρωτεΐνη και αποτελεί τον κύριο υποδοχέα του ΗA. Η ισομορφή που δεν περιέχει ενδιάμεσα εξώνια ονομάζεται CD44s, ενώ όλες οι υπόλοιπες ισομορφές προκύπτουν με εναλλακτικό μάτισμα δέκα διαφορετικών εξωνίων, παράγοντας πληθώρα διαφορετικών μορίων του CD44. Πληθώρα μελετών υποστηρίζει ότι ο μεμβρανικός υποδοχέας CD44 και το ΗΑ υπερεκφράζονται σε πολλές κακοήθειες και η αλληλεπίδρασή τους διεγείρει σειρά λειτουργιών στα κύτταρα του όγκου που συντελούν στην πρόοδο της νόσου. Η κύρια ισομορφή CD44s εκφράζεται ευρέως στους ιστούς και υπερεκφράζεται σε διάφορους τύπους καρκίνου όπου και συνυπάρχει με το ΗΑ, ενώ κάποιες ισομορφές όπως η CD44v5, CD44v6, παίζουν σημαντικό ρόλο στην επιθετικότητα μερικών τύπων καρκίνου. Η έκφραση του CD44 έχει μελετηθεί μερικώς στους όγκους όρχεων και έχουν δημοσιευθεί αντικρουόμενα ευρήματα, ενώ δεν υπάρχουν διαθέσιμα στοιχεία για την έκφραση των ενζύμων που συνθέτουν το ΗΑ. Στόχος της μεταπτυχιακής εργασίας ήταν να διερευνηθεί η έκφραση των ισομορφών του CD44 και των συνθασών του ΗΑ σε τρεις κυτταρικές σειρές όγκων όρχεων (Σεμίνωμα, Εμβρυϊκό καρκίνωμα, Τερατοκαρκίνωμα). Η μελέτη του υποδοχέα CD44 πραγματοποιήθηκε με RT-PCR και ανοσοαποτύπωση. Σε επίπεδο mRNA βρέθηκε πως η κύρια ισομορφή του CD44 που εκφράζεται στο σεμίνωμα καθώς και σε μη- σεμινωματώδεις όγκους είναι η ισομορφή CD44s. Ακόμη στην κυτταρική σειρά σεμινώματος όρχεων εκφράζονται και άλλες ισομορφές, κυρίως όμως εκφράζονται οι ισομορφές CD44v7-v10, CD44v8-v10, CD44v9-v10 και CD44v10. Στις κυτταρικές σειρές μη σεμινωματωδών όγκων (εμβρυϊκό καρκίνωμα και τερατοκαρκίνωμα) εκτός της CD44s ισομορφής που είναι η κυρίαρχη ισομορφή εκφράζονται και κάποιες άλλες ισομορφές του CD44. Στο εμβρυϊκό καρκίνωμα εκφράζονται οι ισομορφές CD44v5,v8, CD44v9-v10 και CD44v10, ενώ στο τερατοκαρκίνωμα παρατηρείται η έκφραση κυρίως της CD44v5,v8, ενώ εκφράζονται και οι CD44v5,v9, CD44v5, CD44v8-v10, CD44v9-v10 και η CD44v10. Η μελέτη του CD44 σε επίπεδο πρωτεΐνης με το αντίσωμα Hermes-3 κατέδειξε πως η κύρια ισομορφή που εκφράζεται στην κυτταρική σειρά σεμινώματος είναι η CD44s με μοριακό βάρος~90kDa. Ακόμα φάνηκε πως υπάρχει έκφραση και κάποιων ισομορφών και θραυσμάτων του CD44 με μικρότερο μοριακό μέγεθος. Αντίθετα στις κυτταρικές σειρές εμβρυϊκού καρκίνωματος και τερατοκαρκινώματος παρατηρήθηκε η έκφραση μόνο της CD44s ισομορφής. Αντίθετα με την υψηλή έκφραση του CD44s στην κυτταρική σειρά σεμινώματος, παρατηρήθηκε μικρή έκφραση του CD44s στην κυτταρική σειρά εμβρυϊκού καρκινώματος και μια ελάχιστη έκφραση στην κυτταρική σειρά του τερατοκαρκινώματος. Η μελέτη του υποδοχέα CD44 σε επίπεδο ιστού έδειξε ότι η πρωτεΐνη του CD44 εκφράζεται στα κύτταρα του όγκου. Η σηματοδοτική δράση του ΗΑ στα καρκινικά κύτταρα μέσω του υποδοχέα CD44 έχει προταθεί ως βασικό βήμα για την ανάπτυξη και πρόοδο της νόσου. Οι συνθάσες του HA είναι τα ένζυμα που βιοσυνθέτουν το ΗΑ και διακρίνονται σε τρεις ισομορφές τις HAS- 1, HAS-2, HAS-3α, και HAS-3β. Στα πλαίσια της μεταπτυχιακής διατριβής βρέθηκε πως η κυτταρική σειρά σεμινώματος εκφράζει μόνο την ισομορφή HAS-3α, ενώ οι κυτταρικές σειρές εμβρυϊκού καρκινώματος και τερατοκαρκινώματος εμφανίζουν ισχυρή έκφραση της ισομορφής HAS-3α και μικρή έκφραση της HAS-2. / Testicular tumors are present in men aged 15-35 years with increasing incidence in the last 40 years. Approximately 95% of these tumors arise from germ cells. The interaction of cells with other cells or with components of the extracellular matrix (ECM), as well as their locomotion on blood vessel endothelium and extravascular tissue, are substantially dependent on the activity of adhesion molecules such as integrins, selectins, members of the immunoglobulin superfamily, addressins, cadherins, and CD44. CD44 is a glycoprotein and represents the major receptor for HA. The isoform with no variant exons is named CD44s, whereas the other isoforms arise from alternative splicing of the 10 variant exons of the CD44 mRNA, producing a huge variety of diverse CD44 molecules. A lot of studies supports that the membrane receptor CD44 and HA are overexpressed in several malignancies and their interaction trigger fuctions in tumour cells, which conduce to the disease progression. The major isoform is the CD44s which is expressed widely in tissues, whereas is overexpressed in several types of tumours ,coexisting with HA. The expression of CD44 has been partly studied in testicular tumours but controversial findings have been published, whereas no data about the enzymes which synthesize HA are available. The aim of this thesis was to examine the expression of CD44 isoforms and HA synthases in three cell lines (seminoma, embryonic carcinoma, teratocarcinoma). The study of CD44 was conducted by RT-PCR analysis and western blotting. It was found that in mRNA level, the major isoform that is expressed in seminoma and nonseminomas is the CD44s isoform. Moreover, in seminoma cell line, other isoforms are also expressed, namely CD44v7-v10, CD44v8-v10, CD44v9-v10 and CD44v10 isoforms. In nonseminomas cell lines CD44s is expressed as the major isoform , but also other isoforms are expressed. CD44v5,v8, CD44v9-v10 and CD44v10 isoforms are expressed in embryonic carcinoma , whereas in teratocarcinoma the expression mainly of the CD44v5,v8 isoform is observed, together with CD44v5,v9, CD44v5, CD44v8-v10, CD44v9-v10 and CD44v10 isoforms. The study of CD44 in protein level conducted by western blotting using the monoclonal antibody Hermes-3. It was shown that the major isoform expressed in seminoma cell line is CD44s with a molecular mass approximately 90kDa. Moreover it was shown that other CD44 isoforms and CD44 fragments with smaller molecular mass are expressed. On the other hand, in embryonic carcinoma and teratocarcinoma cell lines, the expression only of CD44s isoform was observed. The study of CD44 in tissue level revealed that CD44protein is expressed in tumour cells. The signaling effect of HA in tumor cells through CD44 has been stated to be a crucial step in the development and progression of the disease. The synthases of HA are the enzymes that produce HA and represent three distinct isoforms HAS-1, HAS-2, HAS-3a, and HAS-3b. The findings of this study revealed that seminoma cell line express only HAS-3a isoform, whereas embryonic carcinoma and teratocarcinoma cell lines showed high expression of HAS-3a isoform and low expression of HAS-2 isoform.

Made available in DSpace on 2014-12-17T14:13:50Z (GMT). No. of bitstreams: 1 ElielS_DISSERT_partes_autorizadas.pdf: 70324 bytes, checksum: 39ba330935bd00fb14cab6f93f0af7ab (MD5) Previous issue date: 2010-10-17 / OBJECTIVE: Evaluating the kit-Bh performance in carrying out of breast biopsies. METHODS: They were randomly selected a sample of 30 patients with breast cancer undergoing mastectomy, based on the results of a pilot study from February 2008 to April 2010. They were excluded women with had not palpable, stone-hard consistency tumors, previous surgical manipulation or that contains liquid. Using the helicoid biopsy Kit (kit Bh) and an equipment Core biopsy with cannula and needle and 14 gauge respectively, it was collected a fragment of sound equipment in the area and in tumors in each specimen, totaling 120 fragments for histological study. For data analysis, it was defined a 95% confidence level and used the SPSS-13 version, the Kappa index and the parametric Student t test. RESULTS: Mean age of patients was 51.6 years (? 11.1 years). The infiltrating ductal carcinoma showed a higher incidence, 26 cases (86.7%). The Core biopsy had a sensitivity of 93.3%, specificity of 100% and accuracy 96.7%, while the helicoid biopsy had a sensitivity of 96.7%, specificity of 100% and accuracy 98.3%. By comparing the histology of tumors and the fragments of biopsies, there was high degree of agreement in diagnoses (kappa of 0.93 with p <0.05) CONCLUSION: Both devices provided the histological diagnosis of lesions with high accuracy. Results of this study showed that the helicoid biopsy is a reliable alternative in 22 the preoperative diagnosis of breast lesions. Further studies in vivo better will define the role of Kit Bh in the diagnosis of these lesions / OBJETIVO: avaliar o desempenho do Kit Bh na realiza??o de biopsias mam?rias. M?TODOS: de fevereiro de 2008 a abril de 2010, com base nos resultados de um estudo piloto, selecionou-se aleatoriamente uma amostra composta de 30 pacientes portadoras de c?ncer de mama submetidas a mastectomia. Exclu?ram-se as mulheres portadoras de tumor que tivesse consist?ncia p?trea, n?o palp?vel, com manipula??o cir?rgica pr?via ou que contivesse l?quido. Utilizando-se o Kit de biopsia helic?ide ( Kit Bh ) e um equipamentos de Core biopsy com c?nula e agulha de 14 gauge respectivamente, coletou-se um fragmento por equipamento em ?rea s? e nos tumores, em cada pe?a cir?rgica, totalizando 120 fragmentos para estudo histol?gico. Para a an?lise dos dados definiu-se um n?vel de confian?a de 95% e utilizou-se o software SPSS-vers?o 13, o ?ndice de concord?ncia Kappa e o teste param?trico t de Student. RESULTADOS: a m?dia das idades das pacientes foi de 51,6 anos (? 11,1 anos). O Carcinoma ductal infiltrante apresentou maior incid?ncia, 26 casos (86,7%). A Core biopsy apresentou sensibilidade de 93,3%, especificidade de 100% e acur?cia de 96,7%, enquanto a Biopsia helic?ide teve sensibilidade de 96,7%, especificidade de 100% e acur?cia de 98,3%. Na compara??o entre a histologia dos tumores e dos fragmentos de biopsias houve alto grau de concord?ncia nos diagn?sticos ( Kappa igual a 0,93 com p<0,05) CONCLUS?ES: ambos os equipamentos proporcionaram o diagn?stico histol?gico das les?es com alta acur?cia.Os resultados deste estudo demonstraram que a biopsia helic?ide ? uma alternativa confi?vel no diagnostico pr?-operat?rio de les?es mam?rias. Estudos mais aprofundados in vivo, definir?o melhor o papel do Kit Bh no diagn?stico dessas les?es

En oncologie ORL, l'imagerie multiparamétrique est utilisée par un nombre grandissant d'équipes. Parmi les bio-marqueurs, la captation normalisée du fluoro-désoxyglucose (SUV-FDG) en tomoscintigraphie par émission de positons (TEP) et la restriction de la diffusion en IRM (DWI-MRI) sont les plus utilisées.L'IRM couplée à la TEP (TEP/IRM) est une nouveauté qui permet une diminution très significative des doses d'irradiation délivrées par rapport à la TEP/TDM. Nous adressons notre première expérience concernant l'aspect en diffusion et en TEP/IRM dans la surveillance des patients après radio-chimiothérapie. A la question de l'interchangeabilité du FDG-PET et de la DWI-MRI, nous avons tenté d'identifier un lien en imagerie entre la cellularité tumorale et sa consommation glucidique. La cellularité tumorale est approchée en IRM par la mesure du coefficient apparent de diffusion (ADC) et son métabolisme glucidique est approché en TEP en utilisant le 18F-desoxyglucose (FDG) par la mesure de la valeur de fixation normalisée (SUV). Dans une série appariée de 33 patients, nous avons analysé la reproductibilité des mesures de l'ADC et de SUV. Puis nous avons évalué l'indépendance statistique de ces biomarqueurs. Nous avons ensuite voulu comparer les résultats de la TEP obtenus à partir de la TEP/TDM et de la TEP/IRM. Dans une série prospective appariée chez 32 patients explorés en FDG-TEP, nous avons évalué qualitativement les images obtenues par la fusion des images recalées en TEP/IRM et TEP/TDM. Nous avons ensuite comparé la pertinence clinique des deux techniques. Et enfin nous avons comparé les valeurs quantitatives de SUV obtenues du tissu sain et du tissu pathologique. / Multiparametric imaging interest and clinical use is rising for head and neck carcinoma (HNC). Among these modalities, FDG in PET and DWI-MRI are the most studied. PET/MRI is a new modality that allows in a single examination of combined various biologic biomarkers.After an optimization process of PET/MRI, we applied our first experience concerning the aspects of DWI-MRI and PET-MRI after radiation therapy. Thereafter we studied the correlation of SUV and ADC in HNC. In this study SUV and ADC values were independent parameters in HNSCC. Measurements of these two biomarkers were reproducible with almost perfect observer agreements for both methods. Neither SUV nor ADC values were able to predict the histologic grade, although a trend towards higher SUV and lower ADC values was observed in poorly differentiated tumours. Secondly, we we studied detection and quantification of focal uptake in head and neck tumours: 18F-FDG PET/MRI versus PET/CT in 32 consecutive HNSCC who underwent 18F-FDG PET/MRI and PET/CT. Attenuation correction sequence for PET/MRI and CT for PET/CT were used to caculate SUV. In results, PET/MRI coregistration and image fusion was feasible in all patients. There was no statistically significant difference between PET/MRI and PET/CT regarding rating scores for image quality, fusion quality, lesion conspicuity or anatomic location, number of detected lesions and number of patients with and without malignant lesions. A high correlation was observed for SUV measured on PET/MRI and PET/CT. SUV measured on PET/MRI were significantly lower than on PET/CT for malignant tumours, metastatic neck nodes, benign lesions, bone marrow, and liver (p <0.05).

Les carcinomes épidermoïdes de la tête et du cou sont souvent de mauvais pronostic, en raison de leur résistance aux traitements suivie de récidives loco-régionales, voire de métastases. Ce travail s'est focalisé sur le rôle des cellules souches cancéreuses (CSC) dans la radiorésistance d'un modèle cellulaire de cancer du larynx, SQ20B, ainsi que sur leur ciblage thérapeutique en association avec la radiothérapie photonique ou par ions carbone. Une sous-population a été isolée à partir de la lignée SQ20B par tris cellulaires successifs selon 3 critères spécifiques des CSC de tumeurs ORL : exclusion du Hoechst 33342, expression de CD44 et activité élevée de l'aldéhyde déshydrogénase (ALDH). Les cellules SQ20B/SP/CD44 high/ALDHhigh présentent bien les caractéristiques de CSC (tumorisphères, tumorigénèse, radiorésistance). La résistance des CSC aux 2 types d'irradiation, par rapport aux cellules « non souche » SQ20B/SP/CD44low/ALDHlow, implique une diminution de la mort par apoptose, une augmentation des capacités prolifératives ainsi qu'une surexpression de la voie de l'autorenouvellement Bmi1. L'effet radiosensibilisant de 3 molécules ciblant les CSC a été démontré : la mort apoptotique induite par l'UCN-01 en inhibant l'arrêt en phase G2/M ; les capacités prolifératives ciblées par l'acide trans-rétinoïque (ATRA) induisant la différenciation ; et la voie de l'autorenouvellement Bmi-1 inhibée par l'artésunate. Seule ou associées (UCN-01 + ATRA), elles agissent en synergie avec une irradiation par photons ou ions carbone. Des études pré-clinique, puis clinique, devraient confirmer l'intérêt du ciblage des CSC dans le contrôle de l'échappement de ces cancers radiorésistants / Head and neck squamous cell carcinomas (HNSCC) have a poor prognosis, due to their resistance to standard treatments. In most cases, locoregional recurrence or metastases occur. This study has focused on the role of cancer stem cells (CSC) in the radioresistance of the SQ20B HNSCC cell line and their therapeutic targeting in association with photon or carbon ions irradiation. A subpopulation of SQ20B-CSC has been isolated by cell sorting based on 3 specific characteristics of HNSCC-CSC : Hoechst 33342 exclusion, CD44 expression and high aldehyde dehydrogenase activity (ALDH). SQ20B/SP/CD44high/ALDHhigh cells show the CSC characteristics (in vitro and in vivo tumorigenesis, high radioresistance). The response of CSC to both types of irradiation was compared to the non-“stem cells” SQ20B/SP/CD44low sub-population. The observed radioresistance involves a decrease in apoptotic cell death, an increase in proliferative capacities and an overexpression of the Bmi1 self-renewing signaling pathway. The radiosensitizing effects of 3 molecules targeting the CSC has been demonstrated : an induction of apoptotic cell death by the inhibition of the G2/M phase arrest after a treatment with UCN01 ; an inhibition of proliferative capacities using the all-trans-retinoic acid (ATRA) which induce their differentiation ; and an inhibition of Bmi1 by artesunate. These treatments, alone or in combination (UCN01+ATRA) have a synergistic effect with photon or carbon ion irradiation to overcome CSC radioresistance. Preclinical and clinical studies should confirm the benefit of targeting CSC and improve the control of tumor escape in patients with radioresistant HNSCC cancers

No description available.

Deregulation of gene expression caused by genetic or epigenetic changes plays an important role in pathogenesis of cancer. The thesis is a commented collection of ten publications dealing with the molecular biology of tumours. The author has significantly contributed to all of them. All the articles contained in the thesis are linked to the topic of assessment of molecules involved in gene expression regulation (microRNAs) or DNA alterations that affect gene expression (promoter methylation, presence of a fusion gene). MicroRNAs are short single-stranded RNA molecules involved in posttranscriptional regulation of gene expression by triggering mRNA degradation or inhibiting translation. It is a basic mechanism with an impact on all cellular processes including the pathogenesis of various diseases. MicroRNAs can either act as oncogenes by decreasing the expression of tumour-suppressor genes or as tumour-suppressor genes by decreasing the expression of oncogenes. However, the network of microRNA - RNA interactions is much more complex. Our published results that are part of this thesis are focused on colorectal carcinoma (CRC), prostate cancer, head and neck squamous cell carcinoma (HNSCC), gastric cancer and non-small cell lung cancer (NSCLC). In patients with CRC, we demonstrated the prognostic...

Deregulation of gene expression caused by genetic or epigenetic changes plays an important role in pathogenesis of cancer. The thesis is a commented collection of ten publications dealing with the molecular biology of tumours. The author has significantly contributed to all of them. All the articles contained in the thesis are linked to the topic of assessment of molecules involved in gene expression regulation (microRNAs) or DNA alterations that affect gene expression (promoter methylation, presence of a fusion gene). MicroRNAs are short single-stranded RNA molecules involved in posttranscriptional regulation of gene expression by triggering mRNA degradation or inhibiting translation. It is a basic mechanism with an impact on all cellular processes including the pathogenesis of various diseases. MicroRNAs can either act as oncogenes by decreasing the expression of tumour-suppressor genes or as tumour-suppressor genes by decreasing the expression of oncogenes. However, the network of microRNA - RNA interactions is much more complex. Our published results that are part of this thesis are focused on colorectal carcinoma (CRC), prostate cancer, head and neck squamous cell carcinoma (HNSCC), gastric cancer and non-small cell lung cancer (NSCLC). In patients with CRC, we demonstrated the prognostic...

<p dir="ltr">Pancreatic ductal adenocarcinoma (PDAC) remains one of the most deadliest cancer and despite advancements in cancer therapy, remain highly refractory to treatment, largely due to its desmoplastic tumor microenvironment (TME) characterized by complex interactions among cancer cells and stromal components. Particularly, the PDAC associated coagulation system due to leaky tumor vasculatures plays a pivotal role in reshaping the PDAC stroma and its pathogenesis. Understanding the intricate interplay between tumor cells, stromal cells, and the elevated coagulation pathway elements, including tissue factor, thrombin, and fibrin, is essential for developing effective therapeutic strategies. To address these challenges, this research proposes the engineering of a novel PDAC-associated coagulation system using a microfluidic technology, known as coagulation-on-tumor-microenvironment-on-chip (cT-MOC). The study aims to integrate key coagulation pathways in cT-MOC to investigate pivotal interactions in the PDAC stroma: <i>i)</i> thrombin-protease-activated receptors (PARs) mediated promotion of PDAC fibrosis via activation of cancer-fibroblast cross-talk; <i>ii)</i> in-depth analysis of transport and mechanical properties of collagen-fibrin microstructure; <i>iii)</i> inhibited drug delivery in reprogrammed PDAC stroma due to pronounced fibrin deposition on collagen. By leveraging innovative microfluidic technologies and comprehensive experimental approaches, the research endeavors to provide a novel platform that bridges traditional <i>in vitro</i> and <i>in vivo</i> models to overcome the challenges posed by the desmoplastic TME and enhance therapeutic strategies for treatment by targeting the coagulation at the PDAC TME.</p>

Animal testing is still the common method to test the efficacy of new drugs, but tissue engineered in vitro models are becoming more acceptable for replacing and reducing animal testing in anti-cancer drug screening by developing in vitro three-dimensional (3D) tumour models for anti-cancer drug testing. In this study, three-dimensional (3D) culture methods were developed to mimic the tumour microenvironment. 3D culturing is to seed, maintain and expand cultured cells in three-dimensional space, in contrast to the traditional two-dimensional (2D) method in which the cells attach to the bottom of culture containers as monolayers. To mimic the intercellular interplay for tumour study, cell co-culture was applied. In this thesis, perfusion culture showed a better homeostasis for 3D tumour model growth over 17 days, with a more controllable working platform and a more reliable response-dose correlation for data interpretation. In the Matrigel sandwich system, the co-culture of breast cancer cells and endothelial cells demonstrated the morphology featuring a vascular network and tumour structures, with the thickness of the three-dimensional structure around 100µm and tubule length 200-400 µm, and maintained for 10 days. The comparisons studies between Matrigel sandwich and other methods suggest that though not fully characterised, Matrigel is still a valuable scaffold choice for developing co-culture 3D tumour model. Finally, the combination of perfusion and co-culture showed the potential of applying this model in angiogenesis assay, with a drug response profile combining cell viability and morphology to mimic in vivo tumour physiology.

Norrin is a secreted cystine-knot growth factor that plays critical roles in vascular development in the brain, retina, and cochlea, as well as the uterus. Although Norrin is unrelated to the lipid-modified morphogens Wnts, Norrin activates the canonical Wnt/&beta;-catenin pathway by binding to receptor Frizzled4 cysteine-rich domain (Fz4-CRD) and co-receptors of low density lipoprotein receptor related protein 5/6 ectodomain (Lrp5/6-ECD) in conjunction with Tetraspanin-12 (Tspan-12). Like Wnts, Norrin has limited extracellular diffusion properties as a result of associating with heparan sulfate proteoglycans (HSPGs). Mutations lead to inherited disordered retinal vascularization diseases such as Norrie disease, familial exudative vitreoretinopathy and coats' disease. However, the molecular mechanism of how Norrin initiates signalling by engagement with Fz4, Lrp5/6, and HSPGs has remained unresolved. Here, novel strategies for protein production of recombinant human Norrin and Fz4-CRD as well as the complex are developed. The crystal structures of Norrin and its complex with Fz4-CRD, plus complex bound with the heparin mimic sucrose octasulphate, and unliganded structures of Fz4-CRD are presented. These structural data together with biophysical and cellular assays not only reveal the Fz4 and Lrp5/6 binding sites on distinct patches of the Norrin surface, but also indicate the HSPGs binding site on Norrin and Fz4-CRD as well as providing a framework to explain numerous disease-related mutations. Structural comparison with Xenopus Wnt8 in complex with mouse Fz8-CRD provides molecular insights for our understanding of ligand-receptor binding specificity and promiscuity, which has important implications for developing therapeutic strategies against Norrin dependent retinal disorders, and cancers caused by abnormal Wnt signaling.