Upon sperm entry, the vertebrate egg undergoes a series of cell divisions that create a number of smaller cells without increasing the embryonic mass. This induces an elevation of intracellular calcium transient that is conserved across species. In zebrafish, fertilization occurs through an opening in the chorion, the micropyle and in Xenopus it can occur anywhere in the animal hemisphere. Wnt signaling activation is required during dorsal-ventral axis specification and it needs to be suppressed during the regionalization of the brain. Axin is a negative regulator of Wnt signaling and contains an RGS (Regulator of G Protein Signaling) domain. RGS domains are typical of RGS proteins, which are involved in a distinct signaling pathway, G-protein signaling. RGS proteins exert a negative effect of G-protein signaling by accelerating the GTPase activity (GAP) of the Gα subunit, thus turning off the signaling. Axin contains an RGS domain, however, it is not clear whether Axin is directly involved in G-protein signaling. We will also present a work performed using another negative regulator of the Wnt signaling network called naked cuticle (Nkd). Nkd has been shown to modulate β-catenin dependent and independent Wnt signaling. In chapter 2, we will show that the Axin-RGS like function is dispensable during the formation of the dorsal-ventral axis. We manipulated this protein by creating a point mutation in a critical aminoacid within the Axin-RGS domain, known to be detrimental for the GAP function of RGS proteins, Axin1Q162A. Maternal depletion of Axin1 in Xenopus oocytes causes hyperactivation of Wnt signaling and results in dorsalization. Axin1Q162A is able to suppress the dorsalization of maternally depleted embryo and restore normal dorsa-ventral axis formation. In chapter 3, we will describe the role of Axin during the patterning of the vertebrate brain. We show that the point mutant is not able to restore normal brain development in zebrafish embryos after Axin knockdown. We hypothesize that Axin-RGS like function is necessary during the patterning of the vertebrate brain that occurs after zygotic transcription has been initiated. Moreover, we show that Axin-RGS like activity may be dispensable during this stage of development. Finally, we demonstrate that Axin1Q162A localization differs from the wildtype Axin1 and Axin1 but not Axin1Q162A is localized to the plasma membrane upon Gα overexpression in zebrafish embryos. Embryonic organ laterality is preceded by molecular and physiological asymmetries. In chapter 4 we describe the role of another Wnt antagonis, Nkd cuticle, during left-right patterning. Prior to organogenesis, a group of cells called Dorsal Forerunner Cells, (DFCs), migrate ahead of the dorsal blastoderm during gastrulation to form the Kupffer's vesicle (KV). This vesicle will trigger a signaling cascade that will culminate with left-right determination. We show data that support the requirement of Nkd in organ laterality and convergence and extension movements using zebrafish and Xenopus laevis.

Indiana University-Purdue University Indianapolis (IUPUI) / The aging US population is experiencing a growing incidence of osteoporosis, characterized by increased fracture risk and low bone mass. In skeletal tissue, canonical Wnt signaling is a critical regulator of bone mass, and dysregulation of the Wnt pathway has been implicated in numerous skeletal displasias. Some components of the Wnt signaling pathway have a clear role in bone homeostasis, particularly in the response of bone to altered mechanical environment. Other pathway components are more poorly defined. One important intracellular signal transduction node in the Wnt cascade is β- catenin, which modulates gene expression and cell-cell junctions, among other functions. During periods of disuse, β-catenin is degraded, leading to inhibition of Wnt targets. Here, I characterize the role of β-catenin in bone during a disuse challenge, using a genetic mouse model expressing an inducible constitively-active mutant form of β- catenin in the osteocyte population. I hypothesize that prevention of β-catenin degradation during disuse will prevent the bone wasting effects of mechanodeprivation. As a second goal, I focus on upstream (membrane-bound) modulation of Wnt. Here, I investigate the low-density lipoprotein receptor-related receptor 4 (Lrp4), in the regulation of bone mass and mechanotransduction. I generated an Lrp4 knockin mouse model harboring a missense mutation found among human patients with abnormally high bone mass. I hypothesize that the mutation compromises sclerostin action on bone cells. Understanding how each of these components of the Wnt signaling pathway interact, may lead to novel therapeutic targets for treatment of bone diseases.

In vertebrates, the urogenital sinus and the hindgut are connected at a hollow region called cloaca. A midline mesenchymal structure known as urorectal septum (urs) descends from the ventral body wall to separate the urogenital sinus from the hindgut before the formation of an anal opening. Subsequent cloaca membrane regression at the ventral midline of the genital tubercle (GT) is crucial for the formation of an anal opening. These two events are important during cloaca septation in urorectal development. Mice with defective Shh or Wnt signaling displayed similar urorectal defects such as GT agenesis, un-partitioned cloaca (persistent cloaca) and proximal urethral opening that are attributable to increased cell apoptosis. Furthermore, Shh and Wnt signal transduction coordinate with each other and regulate cell survival of the developing urorectum. However, the molecular mechanisms by which these two signaling pathways coordinate in urorectal development remain unclear. We previously identified Wnt inhibitory factor1 (Wif1) from Affymetrix array analysis for genes/pathways that is implicated in urorectal development. Wif1 is a secreted protein that binds directly to Wnt ligands preventing Wnts from binding to receptors. This leads to -catenin degradation and thereby inhibits their activities. It is known that Wif1 binds to Wnt3a and Wnt5a with high affinity and deletion of Wnt3a, Wnt5a and -catenin in mice caused GT agenesis, persistent cloaca and proximal hypospadias. Using ETU-induced anorectal malformations model, I found out that Wif1 is ectopically expressed in the un-tubularized and un-septated urorectum. Wif1 is mainly expressed at the fusing endoderm that associates with programmed cell death during cloaca septation. Exogenous addition of Wif1 protein in urorectum culture also caused cloaca membrane disintegration, and proximal urethral opening that may be due to aberrant apoptosis. Shh and Wif1 are differentially expressed at the cloaca endoderm. In normal mice, Shh is highly expressed at the cloaca endoderm except those Wif1-expressing endodermal cells. Blockage of Shh pathway by cyclopamine in urorectum culture induced ectopic expression of Wif1, concomitant with genital tubercle hypoplasia and un-septated cloaca. More importantly, deletion of Shh in mice hastened Wif1 expression at the cloaca membrane endoderm and elicited increased cell death in the Wif1 expressing endoderm. Wif1-/- embryos display urorectal defects including delayed genital outgrowth and proximal hypospadias. Therefore, disruption of spatiotemporal expression of Wif1 could lead to defective Wnt signaling and contributes to abnormal urorectal development in Shh-/- mutant. Current study revealed that Wif1 is involved in urorectal development and is implicated in urorectal defects. It may function as a pro-apoptotic factor to regulate endodermal cell death which is essential for the septation process. Its specific expression is restricted at the midline cloaca endoderm by Shh signaling to inhibit local Wnt--catenin activities during cloaca septation. I proposed novel hypothetical models to explain (1) the significance of the tempo-spatial expression of Wif1; (2) the significance of cell death; and (3) the molecular mechanism that Shh signaling regulates Wnt signaling activities through Wif1 in urorectal development. / published_or_final_version / Surgery / Doctoral / Doctor of Philosophy

In mammals, the external genitalia, urinary tract and anorectal tract are developed from a common embryonic primordium, the urorectum. Cloaca is the hollow space inside the urorectum that connects the hindgut and the urogenital sinus. During the urorectal development, the external genitalia is formed from the outgrowth of genital tubercle (GT) protruding from the urorectum, while the future urinary tract and anorectal tract are formed by the partition of cloaca during cloacal septation. GT outgrowth and cloacal septation are important developmental events for the formation of genitourinary and anorectal system. In human, dysregulation of these developmental events results in congenital anorectal malformations (ARM). Wnt signaling is one of the key signaling pathways that regulates urorectal development. The activity of Wnt signaling is initiated by the binding of Wnt ligands to cell surface receptors, which can be antagonized by secretory Wnt inhibitors. Dickkopf1 (Dkk1) and Wnt inhibitory factor 1 (Wif1) are secretory Wnt inhibitors implicated in urorectal development. However, the functions of other secretory Wnt inhibitors during urorectal developments remain to be elucidated. In this study, expression analyses showed that Dkk1, Dickkopf2 (Dkk2), Dickkopf4 (Dkk4), Secreted Frizzled-related Protein 1 (Sfrp1) and Wif1 were expressed in the developing urorectum. The dynamic, overlapping and restricted expression patterns of these Wnt inhibitors were closely associated with the GT outgrowth and the cloacal septation events, implying that these Wnt inhibitors functioned in a coordinated manner in defining the field of Wnt signaling activities in the developing urorectum. Wif1 knockout mice (〖Wif1〗^(-/-)) was used as the model to investigate the functions of and the interplay between secretory Wnt inhibitors in urorectal development. GT outgrowth and cloacal septation defects were observed in 〖Wif1〗^(-/-) embryos. Most of the 〖Wif1〗^(-/-) embryos displayed varying degrees of GT outgrowth defects, while septation defects were only occasionally observed. This suggested that GT outgrowth and cloacal septation were regulated by Wif1 via different regulatory mechanisms. In the urorectum of 〖Wif1〗^(-/-) embryos, Dkk1 was significantly upregulated in the peri-cloacal mesenchyme. Further expression analysis suggested that Dkk1 was sufficient to rescue cloacal septation defects but not GT outgrowth defects in 〖Wif1〗^(-/-)embryos. In the 〖Wif1〗^(-/-) embryos with severe GT outgrowth defects, the Fgf8-expressing distal urethral epithelium, the signaling center in the urorectum, was absent, suggesting that the GT outgrowth defects could be contributed by the loss of dUE-expressing signals such as Fgf8. This study demonstrated the importance of secretory Wnt inhibitors in the GT outgrowth and cloacal septation and suggested that secretory Wnt inhibitors played partially overlapping roles in urorectal development. A rescue mechanism for cloacal septation performed by Dkk1 upon Wif1 deletion was proposed. Such auto-regulatory mechanism within the Wnt signaling pathway indicated that Wnt inhibitors play essential regulatory roles in the urorectal development and a balanced Wnt signaling activity modulated by Wnt inhibitors is crucial to the development of urorectum. / published_or_final_version / Surgery / Master / Master of Philosophy

Nasopharyngeal carcinoma (NPC) is closely associated with Epstein-Barr Virus (EBV).Early diagnosis of NPC will improve the overall survival. However, traditional EBV markers do not perform well in high-risk individuals or for early detection of NPC. Aberrant promoter hypermethylation of tumor suppressor genes (TSGs) is an important epigenetic change in early tumorigenesis. This study identified a promising panel of methylation markers for early detection of NPC and assessed the clinical usefulness of these markers using nasopharyngeal (NP) brushing and blood specimens. Methylation-sensitive high resolution melting (MS-HRM) assays were carried out to assess the methylation status of a selected panel of four TSGs (RASSF1A, WIF1, DAPK1, RAR2)in biopsies, NP brushings and cell-free plasma from NPC patients. NP brushing and blood samples from high-risk and cancer-free groups were used as controls. The DNA methylation panel showed higher sensitivity and specificity than the EBV DNA markerincell-free plasma for early stage (Iand II) NPC (sensitivity: 64.6% vs. 51.2% and specificity: 96.0% vs. 88.0%, respectively). In combination with plasma EBV DNA, testing for DNA methylation in plasma and NP brushings using the four-gene MS-HRM test significantly increased the detection rate for all stages of NPC(94.1% for stages I-II, 98.4% for stages III-IV) as well as recurrence(93.5%). Aberrant activation of the Wnt signaling pathway is a common mechanism for cell transformation and tumor development in a variety of human cancers. A high frequency of promoter hypermethylation of WIF1was observed in NPC cell lines (100%), primary tumor biopsies(89.7%), NP brushings (80.2%), and cell-free plasma (51.8%),with no significant correlation with NPC stage. Simultaneously, expression of WIF1 was completely silenced in NPC cell lines (HONE1, HK1, HNE1, SUNE1, CNE1, CNE2, and C666),but not in immortalized NP epithelial cells (NP460 and NP69). These together suggested an important role of WIF1 in NPC development. In vitro and in vivo functional assays revealed a tumor suppressive role of WIF1in NPC. Restoration of WIF1expression in NPC cells significantly suppressed anchorage-independent growth, in vivo tumorigenicity, invasion, migration, and angiogenesis of NPC cells. A number of important angiogenesis-related genes were down-regulated by WIF1expression, including IL6,IL8,VEGF165,VEGFA, PDGFB, and MCP1. There is inhibition of the Wnt/β-catenin signaling pathway, manifested as decreased β-catenin expression and TCF/LEF Wnt promoter activity. These data indicated the important regulatory role of Wnt signaling pathway in NPC tumorigenicity, invasion, migration, and angiogenesis, by interacting with the complex signaling network in NPC cells. To conclude, the MS-HRM assay on the selected gene panel in combination with the EBV DNA test, increases the sensitivity for NPC detection at an early stage and detection of recurrence and has great potential to become a non-invasive test for early diagnosis and disease monitoring after treatment. Collectively, results from this study reveal that WIF1is not only a sensitive biomarker, but also a tumor suppressor gene in NPC. Understanding the molecular regulatory role ofWIF1in NPC will facilitate the diagnosis of NPC, and development of novel NPC therapeutic strategy. / published_or_final_version / Clinical Oncology / Doctoral / Doctor of Philosophy

A cell that senses signals from its environment uses proteins for signal transduction via post translational modifications (PTMs) and protein- protein interactions (PPIs) from cell membrane into the nucleus where genes controlling cell proliferation, differentiation and apoptosis can be turned on or off, i.e. changing the phenotype or fate of the cell. Aberrations within such proteins are prone to cause diseases, such as cancer. Therefore, it is important so study aberrant signaling to be able to understand and treat diseases. In this thesis, signaling aberrations of PTMs and PPIs were analyzed with the use of the in situ proximity ligation assay (in situ PLA), and the thesis also contain method development of rolling circle amplification (RCA), which is the method used for signal amplification of in situ PLA reaction products. Paper I considers the integrity of RCA products. Here, the aim was to generate a smaller and more compact RCA product, for more accurate either visual or automated analysis. This was achieved with the use of an additional so called compaction oligonucleotide that during RCA was able to bind and pull segments of RCA products closer together. The compaction oligonucleotide served to increase the signal to noise ratio and decrease the number of false positive signals. The crosstalk between the Hippo and TGFβ signaling pathways were studied in paper II. Activity of the Hippo signaling pathway is regulated by cell density sensing and tissue control. We found differences in amounts and localization of interactions between the effector proteins of the two pathways depending on cell density and TGFβ stimulation. In paper III the NF-кB signaling pathway constitutively activated in chronic lymphocytic leukemia (CLL) was studied. A 4 base-pair frameshift deletion within the NFKBIE gene, which encodes the negative regulator IкBε, was found among 13 of a total 315 cases by the use of targeted deep sequencing. We found reduced levels of IкBε protein, decreased p65 inhibition, and increased phosphorylation, along with increased nuclear localization of p65 in NFKBIE deleted cases compared to healthy cases. Crosstalk between the Hippo and Wnt signaling pathway are studied within paper IV. Here, we found differences in cellular localization of TAZ/β-catenin interactions depending on colon cancer tumor stage and by further investigate Hippo/WNT crosstalk in cell line model systems we found an increase of complex formations involved in the crosstalk in sparse growing HEK293 cells compared to dense growing cells. Also, active WNT3a signaling was affected by cell density. Since cell density showed to have a big effect on Hippo/WNT crosstalk we continued to investigated the effect of E-cadherin, which has a function in cell junctions and maintenance of epithelial integrity on Hippo/WNT crosstalk. Interestingly, we found that E-cadherin is likely to regulate Hippo/WNT crosstalk.

Les études cliniques et in vitro suggèrent que la sclérose de l’os sous-chondral due aux ostéoblastes (Ob) anormaux est impliquée dans la progression de l’ostéoarthrose (OA). Les Ob OA humains isolés à partir d’os sous-chondral sclérosé montrent un phénotype altéré, un niveau réduit de signalisation Wnt/β-caténine canonique et une minéralisation in vitro réduite. Il existe également deux voies non-canoniques, Wnt/PKC et Wnt/PCP qui ont étés décrites dans la littérature. Cependant, il n’existe aucune étude qui traite de ces deux voies dans les Ob OA. Ces voies sont activées après qu’un ligand Wnt non-canonique tel que Wnt-5a se lie à un récepteur Wnt couplé à des corécepteurs de la voie non-canonique. Ceci enclenche, respectivement pour la voie Wnt/PKC-Ca2+ et Wnt/PCP, la phosphorylation de PKC (p-PKC) et la phosphorylation de JNK (p-JNK) et agit sur les cibles en aval. Nous avons voulu déterminer s’il était possible de constater des altérations dans les voies Wnt non-canoniques dans les Ob OA. Nous avons préparé des cultures primaires d’ostéoblastes sous-chondral humains à partir de plateaux tibiaux de patients OA subissant une arthroplastie totale du genou, ainsi qu’à partir de plateaux tibiaux recueillis à l’autopsie de patients « normaux ». L’expression des gènes impliqués dans les voies Wnt/PKC et Wnt/PCP a été évaluée par RT-qPCR et la production par Western Blot des protéines, ainsi que celle de p-PKC et p-JNK et que l’activité des facteurs NFAT et AP-1 utilisés par ces deux voies. L’activité phosphatase alcaline (ALPase) et la quantité d’ostéocalcine (OC) ont étés évaluées respectivement à l’aide d’hydrolyse de substrat et d’ELISA. Le niveau de minéralisation a été évalué par la coloration au rouge Alizarine. Nos résultats montrent que l’expression et la production de Wnt-5a étaient augmentées dans les Ob OA comparées aux Ob N et LGR5 était significativement plus élevée. De plus, l’expression de LGR5 est directement régulée via la stimulation ou la diminution de Wnt-5a, à la fois au niveau de l’ARNm et des protéines. Par ailleurs, Wnt-5a a stimulé la phosphorylation de JNK et de PKC ainsi que l’activité NFAT et AP-1. Les niveaux de minéralisation ainsi que d’activité ALPase et de sécrétion d’OC ont aussi été affectés par les changements du niveau de Wnt-5a. Ces résultats suggèrent que Wnt-5a, qui est augmentée dans les OA Ob, peut stimuler les voies Wnt non-canoniques et affecter le phénotype et la minéralisation des OA Ob humains. / Clinical and in vitro studies suggest that subchondral bone sclerosis due to abnormal osteoblasts (Ob) is involved in the progression and/or onset of osteoarthritis (OA). Human Ob isolated from sclerotic subchondral OA bone tissue show an altered phenotype, a decreased canonical Wnt/ß-catenin signaling pathway (cWnt), and a reduced mineralization in vitro. Besides the cWnt pathway, at least two non-canonical signaling pathways, the Wnt/PKC and Wnt/PCP pathway have been described. These pathways are activated when a non-canonical Wnt ligand like Wnt-5a binds to a Wnt receptor coupled with non-canonical co-receptors. This activates, respectively for Wnt/PKC-Ca2+ and Wnt/PCP, the phosphorylation of PKC (pPKC) and the phosphorylation of JNK (pJNK) and their effect on downstream targets. However, there are no reports of either pathway in OA Ob. Here, we studied if alterations of the non-canonical pathways could be observed in OA Ob. We prepared primary human subchondral Ob using the tibial plateaus of OA patients undergoing total knee arthroplasty, or from tibial plateaus of normal individuals at autopsy. The expression of genes involved in Wnt/PKC and Wnt/PCP was evaluated by RT-qPCR and their protein production by Western blot analysis, in addition to p-PKC and p-PCP and NFAT and AP-1 activity with luciferase. Alkaline phosphatase activity and osteocalcin levels were evaluated respectively by substrate hydrolysis and ELISA respectively, and mineralization levels were evaluated with Alizarin red staining. OA Ob showed an increased alkaline phosphatase activity and osteocalcin release. The expression of Wnt5a was increased in OA Ob compared to normal. The expression of LGR5 was significantly increased in these cells. Moreover, the expression and production of LGR5 is directly modulated via the stimulation or inhibition of Wnt5a. However, Wnt5a did not stimulate the expression of LGR4. Wnt5a increased the phosphorylation of PKC and JNK as well as NFAT and AP-1 activity. Mineralization levels as well as alkaline phosphatase activity and osteocalcin secretion levels were also linked with changes in Wnt-5a levels. These data indicate that Wnt5a, which is increased in OA Ob, can directly stimulate the Wnt/PKC and Wnt/PCP pathways and this can affect the phenotype and mineralization observed in human OA Ob.

Chronic liver disease remains a significant cause of morbidity and mortality globally. Transplantation is the only effective treatment for end-stage disease but is limited by organ availability, surgical complications and risks of long term immunosuppression. Novel therapies for advanced disease are therefore required. The liver has a remarkable capacity to regenerate through division of mature hepatocytes, however in chronic or severe disease hepatocyte replication fails, senescence occurs and liver failure ensues. Ductular reactions (DRs), containing hepatic progenitor cells capable of repopulating the parenchyma, arise in chronic liver injury when hepatocyte regeneration is impaired. Enhancing this endogenous repair mechanism is a key therapeutic goal. Notch and Wnt are key signals required for liver regeneration, however to date they have principally been characterised in end-point disease and the temporal kinetics of these signalling pathways not known. I sought to identify if these signals control expansion of DRs after hepatocyte injury and whether they can be therapeutically manipulated. I examined the dynamics of Notch and Wnt activity using a genetic model of hepatocellular injury and ductular-mediated regeneration whereby induction of injury could be timed, synchronising the regenerative response. Using lineage tracing, small molecules, blocking antibodies and genetic loss of function experiments I defined distinct time-sensitive Notch and Wnt signatures where early regeneration is driven by Notch and the later response by Wnt. I demonstrated that inhibition of Notch1 and Notch3 but not Notch2 reduces the generation of DRs. I identified that DRs were a source of potent growth hormone IGF1 and this production was Wnt driven. Notch driven expression of IGF1-receptor within DRs identified this axis as a node for cooperation between Notch and Wnt signals. Blocking the IGF1 axis prevented DR expansion, which conversely could be enhanced by administration of recombinant IGF1. Here, I functionally defined complex temporal dynamics controlling of DRs and identified therapeutic pathways to enhance liver regeneration.

Optimisation of the conventional tripartite of pancreatic cancer (PC) treatment have led to significant improvements in mortality, however further knowledge of the underlying molecular processes is still required. Transcript profiling of mRNA expression of over 44K genes with microarray technology demonstrated upregulation of secreted frizzled related protein 4 (sFRP4) and ??-catenin in PC compared to normal pancreata. Their pathway ??? Wnt signalling is integral to transcriptional regulation and aberrations in these molecules are critical in the development of many human malignancies. Immunohistochemistry protocols were evaluated by two independent blinded examiners for antigen expression differences associated with survival patterns in 140 patients with biopsy verified PC and a subset of 23 normal pancreata with substantial observer agreement (kappa value 0.6-0.8). A retrospective cohort was identified from 6 Sydney hospitals between 1972-2003 and archival formalin fixed tissue was collected together with clinicopathological data. Three manual stepwise regression models were fitted for overall, disease-specific and relapse-free survival to determine the value of significant prognostic variables in risk stratification. The models were fitted in a logical order using a careful strategy with step by step interpretation of the results. Immunohistochemistry demonstrated increased sFRP4 membranous expression (&gt 10%) in 49/95 PC specimens and this correlated with improved overall survival (HR:0.99;95%CI:0.97-6.40;LRchi2=134.75; 1df; ??&lt 0.001). Increased sFRP4 cytoplasmic staining (&gt 2/3) in 46/85 patients increased the disease-specific survival (HR:0.52;95%CI:0.31-0.89;LR test statistic =248.40;1df;??&lt 0.001). Increasing ??-catenin membranous expression (&lt _60%) in 26/116 patients was associated with an increased risk of overall death (HR:3.18;95%CI:1.14-8.89;LR test statistic =4.61;1df,??&lt 0.05). Increasing cytoplasmic expression in 65/114 patients was protective and was associated with prolonged survival on univariate, but not multivariate analysis (Disease specific survival HR:0.75;95%CI:0.56-1.00;logrank chi2=3.91;1df; ??=0.05). Increased nuclear ??-catenin expression in 65/114 patients was associated with prolonged survival (disease-specific HR:0.92;95%CI:0.83-1.02; LR test statistic= 49.72;1df;??&lt 0.001). At the conclusion, 12 patients (8.6%) remained alive, 122 died of their disease (68 males versus 54 females). They were followed for a median of 8.7 months (range 1.0-131.3) months. The median age was 66.5 years (range 34.4-96.0, standard deviation 10.9) years. Pancreatic resection was achieved in 79 patients with 46.8% achieving RO resection. The 30 day post-operative mortality was 2.1%. The overall 1 year survival rate was (33.7% ; 95%CI: 25.78-33.79) with a 5 year survival of (2.87%, 95%CI: 2.83-6.01) and a median survival of (8.90 months; 95%CI: 7.5-10.2). The median disease-specific survival was (9.40; 95%CI: 7.9-10.5 months) and the median time to relapse was 1.2 months (95%CI 1.0-1.2 months). A central tenet of contemporary cancer research is that an understanding of the genetic and molecular abnormalities that accompany the development and progression of cancer is critical to further advances in diagnosis, treatment and eventual prevention. High throughput tissue microarrays were used to study expression of two novel tumour markers in a cohort of pancreatic cancer patients and identified sFRP4 and ??-catenin as potential novel prognostic markers.

No description available.