Overexpression of Wnt-2 in colorectal cancers

mRNA coexpression patterns of Wnt pathway components and their clinicopathological associations in breast and colorectal cancer

Aberrant Wnt signaling is implicated in carcinogenesis triggering efforts for the development of new therapeutic agents, many of which have entered clinical trials. We extend our previous analysis of WNT3, FZD7, LEF1 expression levels in breast and colorectal cancer including WNT2, FZD4 and β-catenin expression, in an effort to delineate their relative expression levels along with concurrent expression patterns and possible prognostic value. We analyzed 82 breast and 102 colorectal carcinomas for relative mRNA expression levels of the investigated genes by RT-PCR relative quantification with the ΔΔCt method. Statistical analysis was performed in order to determine associations of relative mRNA expression and linear correlations. β-catenin expression was determined by immunochemistry. Regarding breast carcinomas, decreased relative mRNA expression levels of WNT2, FZD4 were found frequently and WNT2 expression was correlated with ER/ PR status (p = 0.045/p = 0.028), whereas β-catenin with grade (p = 0.026). In colorectal carcinomas, increased relative mRNA expression levels of WNT2 and FZD4 were found in 59% and 32% of cases respectively, whereas β-catenin showed decreased mRNA expression levels in 57% of cases and a correlation with pN-category (p = 0.037). Linear correlations were observed between WNT2/FZD4 (R=0.542, p < 0.001), WNT2/β-catenin (R=0.254, p = 0.010), FZD4/β-catenin (R=0.406, p < 0.001) expression and a correlation between mRNA expression and membranous/cytoplasmic β-catenin emerged (p = 0.039/0.046). Our results suggest a possible clinical significance for Wnt pathway gene expression levels in both tumour types. The concurrent expression of the investigated genes as well as the different expression profiles, underlines the complexity of this pathway and the necessity of patient selection in order to maximize the efficacy of drugs targeting Wnt pathway.

miR-188-5p inhibits proliferation, migration, and invasion in gallbladder carcinoma by targeting Wnt2b and Smad2

Gallbladder carcinoma (GBC) commonly occurs in gastrointestinal malignancy and has the fifth highest mortality rate among gastrointestinal malignancy. Recently, miR-188-5p, a small noncoding RNA, has been implicated in various types of cancer such as nasopharyngeal carcinoma, oral squamous cell carcinoma, liver cancer, and prostate cancer. However, the effect of miR-188-5p on GBC remains unclear. Here, we demonstrated that miR-188-5p was downregulated in GBC tissues, and downregulation of miR-188-5p correlated with larger tumor size, lymph node metastasis, and extensive metastasis. In addition, the overall survival time of patients with higher miR-188-5p expression was significantly longer than that of patients with low-miR-188-5p expression. Moreover, downregulation of miR-188-5p promoted the proliferation, migration, and invasion of GBC cells, while its overexpression inhibited cell invasion and induced cell apoptosis, and arrested GBC growth in vivo. Importantly, miR-188-5p-dependent tumorigenesis was correlated with Wnt/β-catenin signaling and p-38/JNK signaling. In conclusion, miR-188-5p plays a direct role in GBC tumorigenesis. Our study suggests that miR-188-5p could serve as a novel diagnosis marker and therapeutic target in GBC.

Circular RNA profile identifies circOSBPL10 as an oncogenic factor and prognostic marker in gastric cancer

The prognosis after curative resection of gastric cancer (GC) remains unsatisfactory, and thus, the development of treatments involving alternative molecular and genetic targets is critical. Circular RNAs (circRNAs), which are newly discovered molecules with key roles in the non-coding RNA network, have been identified as critical regulators in various cancers. Here, we aimed to determine the circRNA expression profile and to investigate the functional and prognostic significance of circRNA in GC. Using next-generation sequencing profiling, we first characterized an abundant circRNA in GC, hsa_circ_0008549, derived from the OSBPL10 gene and named it circOSBPL10. The expression of circOSBPL10 was found to be upregulated in GC tissues by quantitative RT-PCR, and silencing of circOSBPL10 significantly inhibited GC cell growth, migration, and invasion in multiple experiments. We further confirmed that miR-136-5p is a downstream target of circOSBPL10 using RNA pull-down and luciferase reporter assays. Rescue experiments confirmed that circOSBPL10 regulates biological functions in GC cells via a circOSBPL10-miR-136-5p-WNT2 axis. In vivo experiments showed that circOSBPL10 promotes tumor growth and metastasis in mice. Furthermore, the level of circOSBPL10 was observed to be a prognostic marker of the overall survival and disease-free survival of patients with GC. Taken together, our findings reveal that circOSBPL10 may serve as a new proliferation factor and prognostic marker in GC.

c-Cbl Expression Correlates with Human Colorectal Cancer Survival and Its Wnt/β-Catenin Suppressor Function Is Regulated by Tyr371 Phosphorylation

The proto-oncogene β-catenin drives colorectal cancer (CRC) tumorigenesis. Casitas B-lineage lymphoma (c-Cbl) inhibits CRC tumor growth through targeting nuclear β-catenin by a poorly understood mechanism. In addition, the role of c-Cbl in human CRC remains largely underexplored. Using a novel quantitative histopathologic technique, we demonstrate that patients with high c-Cbl-expressing tumors had significantly better median survival (3.7 years) compared with low c-Cbl-expressing tumors (1.8 years; P = 0.0026) and were more than twice as likely to be alive at 3 years compared with low c-Cbl tumors (P = 0.0171). Our data further demonstrate that c-Cbl regulation of nuclear β-catenin requires phosphorylation of c-Cbl Tyr371 because its mutation compromises its ability to target β-catenin. The tyrosine 371 (Y371H) mutant interacted with but failed to ubiquitinate nuclear β-catenin. The nuclear localization of the c-Cbl-Y371H mutant contributed to its dominant negative effect on nuclear β-catenin. The biological importance of c-Cbl-Y371H was demonstrated in various systems, including a transgenic Wnt-8 zebrafish model. c-Cbl-Y371H mutant showed augmented Wnt/β-catenin signaling, increased Wnt target genes, angiogenesis, and CRC tumor growth. This study demonstrates a strong link between c-Cbl and overall survival of patients with CRC and provides new insights into a possible role of Tyr371 phosphorylation in Wnt/β-catenin regulation, which has important implications in tumor growth and angiogenesis in CRC.

Colorectal cancer cells suppress CD4+ T cells immunity through canonical Wnt signaling

Understanding how colorectal cancer escapes from immunosurveillance and immune attack is important for developing novel immunotherapies for colorectal cancer. In this study we evaluated the role of canonical Wnt signaling in the regulation of T cell function in a mouse colorectal cancer model. We found that colorectal cancer cells expressed abundant Wnt ligands, and intratumoral T cells expressed various Frizzled proteins. Meanwhile, both active β-catenin and total β-catenin were elevated in intratumoral T cells. In vitro study indicated that colorectal cancer cells suppressed IFN-γ expression and increased IL-17a expression in activated CD4⁺ T cells. However, the cytotoxic activity of CD8⁺ T cells was not altered by colorectal cancer cells. To further evaluate the importance of Wnt signaling for CD4⁺ T cell-mediated cancer immunity, β-catenin expression was enforced in CD4⁺ T cells using lentiviral transduction. In an adoptive transfer model, enforced expression of β-catenin in intratumoral CD4⁺ T cells increased IL-17a expression, enhanced proliferation and inhibited apoptosis of colorectal cancer cells. Taken together, our study disclosed a new mechanism by which colorectal cancer impairs T cell immunity.

A transcriptome-based protein network that identifies new therapeutic targets in colorectal cancer

Background

Colon cancer occurrence is increasing worldwide, making it the third most frequent cancer. Although many therapeutic options are available and quite efficient at the early stages, survival is strongly decreased when the disease has spread to other organs. The identification of molecular markers of colon cancer is likely to help understanding its course and, eventually, to uncover novel genes to be targeted by drugs. In this study, we compared gene expression in a set of 95 human colon cancer samples to that in 19 normal colon mucosae, focusing on 401 genes from 5 selected pathways (Apoptosis, Cancer, Cholesterol metabolism and lipoprotein signaling, Drug metabolism, Wnt/beta-catenin). Deregulation of mRNA levels largely matched that of proteins, leading us to build in silico protein networks, starting from mRNA levels, to identify key proteins central to network activity.

Results

Among the analyzed genes, 10.5% (42) had no reported link with colon cancer, including the SFRP1, IGF1 and ADH1B (down), and MYC and IL8 (up), whose encoded proteins were most interacting with other proteins from the same or even distinct networks. Analyzing all pathways globally led us to uncover novel functional links between a priori unrelated or rather remotely connected pathways, such as the Drug metabolism and the Cancer pathways or, even more strikingly, between the Cholesterol metabolism and lipoprotein signaling and the Cancer pathways. In addition, we analyzed the responsiveness of some of the deregulated genes essential to network activities, to chemotherapeutic agents used alone or in presence of Lovastatin, a lipid-lowering drug. Some of these treatments could oppose the deregulations occurring in cancer samples, including those of the CHECK2, CYP51A1, HMGCS1, ITGA2, NME1 or VEGFA genes.

Conclusions

Our network-based approach allowed discovering genes not previously known to play regulatory roles in colon cancer. Our results also showed that selected drug treatments might revert the cancer-specific deregulation of genes playing prominent roles within the networks operating to maintain colon homeostasis. Among those genes, some could constitute novel testable targets to eliminate colon cancer cells, either directly or, potentially, through the use of lipid-lowering drugs such as statins, in association with selected anticancer drugs.

Electronic supplementary material

The online version of this article (10.1186/s12864-017-4139-y) contains supplementary material, which is available to authorized users.

SerpinB3 upregulates the Cyclooxygenase-2 / β-Catenin positive loop in colorectal cancer

Colorectal cancer is characterized by aberrant Cyclooxigenase-2 (COX-2) and β-Catenin pathways. Recently, the protease inhibitor SerpinB3 has been described overexpressed in more advanced stages of this tumor. Aim of the study was to explore the possible relationship between these molecules in this setting. We evaluated colorectal cancer specimens from 105 patients and a positive correlation between SerpinB3, COX-2 and β-Catenin expression was observed, with higher levels in tumor than in adjacent tissue. The highest levels were associated with pathologic parameters of poor prognosis, including vascular invasion, lymph node metastasis and perineural invasion. The molecular and protein profiles of COX-2 and β-Catenin were analyzed in cell lines with different expression of SerpinB3. In those with high expression of SerpinB3, COX-2 and β-Catenin were higher than in controls. Cells with high levels of SerpinB3 showed higher proliferation and invasion compared to controls. In conclusion, in colorectal cancer SerpinB3, COX-2 and β-Catenin are positively correlated and associated with more advanced tumor stage. The in vitro experimental results support a driving role of SerpinB3 in the upregulation of COX-2/ β-Catenin positive loop, associated with a more aggressive cellular phenotype.

Influence of polymorphisms in the Wnt/β-catenin pathway genes on hepatocellular carcinoma risk in a Chinese Han population

The Wnt/β-catenin pathway plays a vital role in initiating and sustaining hepatocellular carcinoma (HCC). However, few studies have investigated polymorphisms in the Wnt/β-catenin signaling pathway genes in the Chinese Han population. The aim of the present retrospective study was to investigate the correlations between polymorphisms of the Wnt/β-catenin signaling pathway genes (CTNNB1 and WNT2) and HCC susceptibility, development, and progression.Twenty tagging single nucleotide polymorphisms were chosen from HapMap data and genotyped in 320 patients with HCC, 320 chronic hepatitis B virus (HBV)-infected patients without HCC (N-HCC, including 95 liver cirrhosis, 164 chronic hepatitis B, and 61 asymptomatic HBV carriers), and 320 healthy controls. Associations between polymorphisms in the 2 Wnt/β-catenin signaling pathway genes (CTNNB1 and WNT2) and HCC susceptibility, development, and progression were investigated.Genotype AA (P = 0.002, odds ratio [OR] = 2.524) and allele A (P = 0.0003, OR = 1.613) of the WNT2 rs4730775 polymorphism were associated with HCC susceptibility compared with healthy controls. Genotype GA (P = 0.001, OR = 0.567) and allele A (P = 0.002, OR = 0.652) of rs3864004, and genotype AG (P = 0.0004, OR = 0.495) and allele G (P = 0.001, OR = 0.596) of rs11564475 in the CTNNB1 gene were correlated with HCC compared with N-HCC patients. These findings were consistent in dominant and recessive models. Multidimensionality reduction analysis revealed that interactions among rs3864004, rs11564475, and rs4730775 were significantly associated with HCC compared with N-HCC patients. The polymorphism rs4135385 of CTNNB1 genotype GA was associated with a higher risk for Stage III + IV HCC (modified Union for International Cancer Control) (P = 0.001, OR = 2.238).Genetic polymorphisms in the WNT2 and CTNNB1 genes were closely associated with HCC risk and progression in a Chinese Han population.

Growth retardation induced by avian leukosis virus subgroup J associated with down-regulated Wnt/β-catenin pathway

Avian leukosis virus subgroup J (ALV-J), an oncogenic retrovirus, induces growth retardation and neoplasia in chickens, leading to enormous economic losses in poultry industry. Increasing evidences showed several signal pathways involved in ALV-J infection. However, what signaling pathway involved in growth retardation is largely unknown. To explore the possible signaling pathway, we tested the cell proliferation and associated miRNAs in ALV-J infected CEF cells by CCK-8 and Hiseq, respectively. The results showed that cell proliferation was significantly inhibited by ALV-J and three associated miRNAs were identified to target Wnt/β-catenin pathway. To verify the Wnt/β-catenin pathway involved in cell growth retardation, we analyzed the key molecules of Wnt pathway in ALV-J infected CEF cells. Our data demonstrated that protein expression of β-catenin was decreased significantly post ALV-J infection compared with the normal (P < 0.05). The impact of this down-regulation caused low expression of known target genes (Axin2, CyclinD1, Tcf4 and Lef1). Further, to obtain in vivo evidence, we set up an ALV-J infection model. Post 7 weeks infection, ALV-J infected chickens showed significant growth retardation. Subsequent tests showed that the expression of β-catenin, Tcf1, Tcf4, Lef1, Axin2 and CyclinD1 were down-regulated in muscles of growth retardation chickens. Taken together, all data demonstrated that chicken growth retardation caused by ALV-J associated with down-regulated Wnt/β-catenin signaling pathway.

Wnt2 complements Wnt/β-catenin signaling in colorectal cancer

Wnt2 is implicated in various human cancers. However, it remains unknown how Wnt2 is upregulated in human cancer and contributes to tumorigenesis. Here we found that Wnt2 is highly expressed in colorectal cancer (CRC) cells. In addition to co-expression of Wnt2 with Wnt/β-catenin target genes in CRC, knockdown or knockout of Wnt2 significantly downregulates Wnt/β-catenin target gene expression in CRC cells. Importantly, depletion or ablation of endogenous Wnt2 inhibits CRC cell proliferation. Similarly, neutralizing secreted Wnt2 reduces Wnt target gene expression and suppresses CRC cell proliferation. Conversely, Wnt2 increases cell proliferation of intestinal epithelial cells. Intriguingly, WNT2 expression is transcriptionally silenced by EZH2-mediated H3K27me3 histone modification in non-CRC cells, However, WNT2 expression is de-repressed by the loss of PRC2's promoter occupancy in CRC cells. Our results reveal the unexpected roles of Wnt2 in complementing Wnt/β-catenin signaling for CRC cell proliferation.

WNT2 Promotes Cervical Carcinoma Metastasis and Induction of Epithelial-Mesenchymal Transition

Background

Previously, we found an 11-gene signature could predict pelvic lymph node metastasis (PLNM), and WNT2 is one of the key genes in the signature. This study explored the expression and underlying mechanism of WNT2 in PLNM of cervical cancer.

Methods

WNT2 expression level in cervical cancer was detected using western blotting, quantitative PCR, and immunohistochemistry. Two WNT2-specific small interfering RNAs (siRNAs) were used to explore the effects of WNT2 on invasive and metastatic ability of cancer cells, and to reveal the possible mechanism of WNT2 affecting epithelial—mesenchymal transition (EMT). The correlation between WNT2 expression and PLNM was further investigated in clinical cervical specimens.

Results

Both WNT2 mRNA and protein expression was upregulated in cervical cancer. High WNT2 expression was significantly associated with tumor size, lymphovascular space involvement, positive parametrium, and most importantly, PLNM. PLNM and WNT2 expression were independent prognostic factors for overall survival and disease-free survival. WNT2 knockdown inhibited SiHa cell motility and invasion and reversed EMT by inhibiting the WNT2/β-catenin pathway. WNT2 overexpression in cervical cancer was associated with β-catenin activation and induction of EMT, which further contributed to metastasis in cervical cancer.

Conclusion

WNT2 might be a novel predictor of PLNM and a promising prognostic indicator in cervical cancer.

Aberrant activation of Wnt/β-catenin signaling drives proliferation of bone sarcoma cells

Bone sarcomas such as osteosarcoma and chondrosarcoma are frequently refractory to conventional chemotherapy and radiotherapy that exhibit poor prognosis. The Wnt signaling are evolutionarily conserved and implicated in cell proliferation and sarcomagenesis. However, the potential role of the Wnt signaling in bone sarcomas is still unclear. Here we demonstrate aberrant activation of Wnt/β-catenin signaling in bone sarcoma cells, involving an autocrine Wnt signaling loop with upregulation of specific Wnt ligands and receptors. Activation of Wnt/β-catenin signaling with Wnt3a or GSK-3β inhibitor drives the proliferation of bone sarcoma cells, whereas downregulation of activated Wnt signaling with dnTCF4 or siLEF1 suppresses bone sarcoma proliferation and induces cell cycle arrest. Taken together, our findings establish the evidence that aberrant activation of Wnt/β-catenin pathway involving an autocrine Wnt singaling drives the proliferation of bone sarcoma cells, and identify the autocrine activation of the Wnt/β-catenin signaling as a potential novel therapeutic target for bone sarcomas.

Wnt2 protein plays a role in the progression of pancreatic cancer promoted by pancreatic stellate cells

This study aimed to investigate the expression of Wnt2 protein in pancreatic cancer tissues and pancreatic stellate cells (PSCs), and determine its effect on the biological functions of pancreatic cancer cells. Immunohistochemistry was used to study the expression pattern of Wnt2 in pancreatic cancer tissues. The relationship between Wnt2 protein expression level and patient prognosis was analyzed. PSCs were isolated and cultured. The expression of Wnt2 in activated PSCs was investigated using Western blot and immunofluorescence. We also analyzed the effect of Wnt2 recombinant protein and stellate cell culture supernatant on the Wnt/β-catenin signaling pathway, as well as the effect of Wnt2 recombinant protein on the biological functions of pancreatic cancer cells. The expression of Wnt2 in interstitial cells of pancreatic cancer was correlated with the prognosis of pancreatic cancer. Wnt2 protein was expressed in activated PSCs. Both stellate cell culture supernatant and Wnt2 recombinant protein could activate the classic Wnt/β-catenin signaling pathway. Wnt2 protein enhanced the migration, invasion, and metastasis of pancreatic cancer cells. These results suggested that Wnt2 protein secreted by PSCs promoted the progression of pancreatic cancer by activating the classic Wnt/β-catenin signaling pathway.

Boosting Wnt activity during colorectal cancer progression through selective hypermethylation of Wnt signaling antagonists

BACKGROUND

There is emerging evidence that Wnt pathway activity may increase during the progression from colorectal adenoma to carcinoma and that this increase is potentially an important step towards the invasive stage. Here, we investigated whether epigenetic silencing of Wnt antagonists is the biological driver for this increased Wnt activity in human tissues and how these methylation changes correlate with MSI (Microsatelite Instability) and CIMP (CpG Island Methylator Phenotype) statuses as well as known mutations in genes driving colorectal neoplasia.

METHODS

We conducted a systematic analysis by pyrosequencing, to determine the promoter methylation of CpG islands associated with 17 Wnt signaling component genes. Methylation levels were correlated with MSI and CIMP statuses and known mutations within the APC, BRAF and KRAS genes in 264 matched samples representing the progression from normal to pre-invasive adenoma to colorectal carcinoma.

RESULTS

We discovered widespread hypermethylation of the Wnt antagonists SFRP1, SFRP2, SFRP5, DKK2, WIF1 and SOX17 in the transition from normal to adenoma with only the Wnt antagonists SFRP1, SFRP2, DKK2 and WIF1 showing further significant increase in methylation from adenoma to carcinoma. We show this to be accompanied by loss of expression of these Wnt antagonists, and by an increase in nuclear Wnt pathway activity. Mixed effects models revealed that mutations in APC, BRAF and KRAS occur at the transition from normal to adenoma stages whilst the hypermethylation of the Wnt antagonists continued to accumulate during the transitions from adenoma to carcinoma stages.

CONCLUSION

Our study provides strong evidence for a correlation between progressive hypermethylation and silencing of several Wnt antagonists with stepping-up in Wnt pathway activity beyond the APC loss associated tumour-initiating Wnt signalling levels.

Activation of Wnt signaling inhibits the pro-apoptotic role of Notch in gastric cancer cells

Notch and Wnt signaling play critical roles in the regulation of development and diseases. Several studies have previously reported that Notch may be a therapeutic target in the treatment of various types of human cancer. In this study, we report that activation of Notch1 inhibits the proliferation of BGC-823 gastric cancer cells. However, the activation of the Wnt/β‑catenin signaling pathway promotes the growth of BGC-823 cells. Furthermore, the combinational activation of the two signaling pathways promotes the proliferation of BGC-823 cells. These data suggest that the activation of Wnt signaling overcomes the pro-apoptotic role of Notch in BGC-823 gastric cancer cells.

Association of Wnt2 and sFRP4 expression in the third trimester placenta in women with severe preeclampsia

BACKGROUND

The Wnt signaling pathway is a conserved pathway and plays a crucial role in regulating trophoblast functions. Abnormal expression of the Wnt pathway may result in the dysfunction of the trophoblast that can contribute to the pathogenesis of preeclampsia (PE). However, published data regarding the association between Wnt pathway and PE in human pregnancy is rare.

OBJECTIVE

The aims of this study were to investigate the expression pattern of Wnt2 and secreted frizzled-related protein 4 (sFRP4) in the third trimester human placenta and to evaluate the relationship between changes in placental Wnt2 and sFRP4 expression and severe PE.

METHODS

The expression of Wnt2 and sFRP4 in normal and severe PE placentas was examined using immunohistochemistry (IHC), real-time polymerase chain reaction, and Western blot.

RESULTS

Compared to the controls, the relative expression of Wnt2 messenger RNA was remarkably downregulated in the PE placentas, while there was no significant difference in sFRP4 between the 2 groups. The IHC indicated that Wnt2 and sFRP4 were expressed predominantly in the villous syncytiotrophoblast and the extravillous trophoblast, whereas Wnt2 in the control group showed higher staining intensity than in the PE group, and sFRP4 in the PE group had a higher staining intensity than in the control group. Furthermore, the results of the Western blots were consistent with the IHC.

CONCLUSIONS

The Wnt signaling pathway was detected in human third trimester placentas, and the decreased placental expression of Wnt2 and increased placental expression of sFRP4 may be associated with the pathogenesis of severe PE.

Expression and prognostic significance of wnt7a in human endometrial carcinoma

Introduction. Wnt7a is a secreted glycoprotein that regulates normal cellular proliferation and differentiation as well as tumorigenesis and progression. However, less is understood about the role of Wnt7a in human endometrial carcinoma. The aim of this study is to investigate the expression and prognostic significance of Wnt7a in endometrial carcinoma. Methods. Wnt7a expression was immunohistochemically examined in 35 normal endometrium, 33 hyperplastic endometrium and 70 endometrial carcinomas. Results. Wnt7a expression was lower in endometrial carcinomas compared with that in normal and hyperplastic endometrium (P < 0.001). Wnt7a was inversely correlated with FIGO stage (P = 0.001), grade (P = 0.001), lymph node metastasis (P = 0.002), depth of myometrial invasion (P = 0.006), lymph vascular space involvement (P = 0.001) and peritoneal cytology (P = 0.013). There was a negative correlation between estrogen receptor (ER) and Wnt7a (r = −0.281, P = 0.019), and a positive correlation between progestogen receptor (PR) and Wnt7a (r = 0.249, P = 0.037). Patients with lost or reduced Wnt7a expression had poorer progression-free survival (PFS) and overall survival (OS) (P = 0.005 and P = 0.042, resp.) on univariate analysis. But on multivariate analysis, Wnt7a expression was not an independent prognostic factor for PFS or OS. Conclusions. Our results indicate that Wnt7a expression may serve as an important prognostic marker.

WNT10A plays an oncogenic role in renal cell carcinoma by activating WNT/β-catenin pathway

Renal cell carcinoma (RCC) is a malignancy with poor prognosis. WNT/β-catenin signaling dysregulation, especially β-catenin overactivation and WNT antagonist silencing, is associated with RCC carcinogenesis and progression. However, the role of WNT ligands in RCC has not yet been determined. We screened 19 WNT ligands from normal kidney and RCC cell lines and tissues and found that WNT10A was significantly increased in RCC cell lines and tissues as compared to that in normal controls. The clinical significance of increase in WNT10A was evaluated by performing an immunohistochemical association study in a 19-year follow-up cohort comprising 284 RCC and 267 benign renal disease (BRD) patients. The results of this study showed that WNT10A was dramatically upregulated in RCC tissues as compared to that in BRD tissues. This result suggests that WNT10A, nuclear β-catenin, and nuclear cyclin D1 act as independent risk factors for RCC carcinogenesis and progression, with accumulative risk effects. Molecular validation of cell line models with gain- or loss-of-function designs showed that forced WNT10A expression induced RCC cell proliferation and aggressiveness, including higher chemoresistance, cell migration, invasiveness, and cell transformation, due to the activation of β-catenin-dependent signaling. Conversely, WNT10A siRNA knockdown decreased cell proliferation and aggressiveness of RCC cells. In conclusion, we showed that WNT10A acts as an autocrine oncogene both in RCC carcinogenesis and progression by activating WNT/β-catenin signaling.

A novel 3-arylethynyl-substituted pyrido[2,3,-b]pyrazine derivatives and pharmacophore model as Wnt2/β-catenin pathway inhibitors in non-small-cell lung cancer cell lines

We developed Wnt/β-catenin inhibitors by identifying 13 number of 3-arylethynyl-substituted pyrido[2,3,-b]pyrazine derivatives that were able to inhibit the Wnt/β-catenin signal pathway and cancer cell proliferation. In the optimization process, a series of 2,3,6-trisubstituted pyrido[2,3,-b]pyrazine core skeletons showed were shown to higher activity than 2,3,6-trisubstituted quinoxaline's and thus hold promise for use as potential small-molecule inhibitors of the Wnt/β-catenin signal pathway in non-small-cell lung cancer cell (NSCLC) lines. And we have studied the pharmacophore mapping for compound 954, which presented the highest activity with a fit value of 2.81. The pharmacophore mapping for the compounds including 954, pyrido[2,3,-b]pyrazine core had hydrogen-bond acceptor site and hydrophobic center roles.

Targeting the Wnt/β-catenin signaling pathway in human cancers

INTRODUCTION

The Wnt/β-catenin signaling pathway plays a pivotal role in the regulation of cell growth, cell development and the differentiation of normal stem cells. Constitutive activation of the Wnt/β-catenin signaling pathway is found in many human cancers, and is thus an attractive target for anti-cancer therapy. Specific inhibitors of this pathway have been keenly researched and developed.

AREAS COVERED

This review discusses the potential of inhibiting the Wnt/β-catenin signaling pathway, as a therapeutic approach for cancer, along with an overview of the development of specific inhibitors.

EXPERT OPINION

Cancer stem cells (CSCs) play a significant role in the development and recurrence of several cancers, and Wnt/β-catenin signaling is important for the proliferation of CSCs. Inhibition of Wnt/β-catenin signaling is therefore a promising treatment approach. Progress has been made in the development of screening methods to identify Wnt/β-catenin signaling inhibitors. Biomarker-based screening is an effective and promising method for the identification of compounds of interest.

Wnt signaling and colon carcinogenesis: beyond APC

Activation of the Wnt signaling pathway via mutation of the adenomatous polyposis coli gene (APC) is a critical event in the development of colon cancer. For colon carcinogenesis, however, constitutive signaling through the canonical Wnt pathway is not a singular event. Here we review how canonical Wnt signaling is modulated by intracellular LEF/TCF composition and location, the action of different Wnt ligands, and the secretion of Wnt inhibitory molecules. We also review the contributions of non-canonical Wnt signaling and other distinct pathways in the tumor micro environment that cross-talk to the canonical Wnt pathway and thereby influence colon cancer progression. These ‘non-APC’ aspects of Wnt signaling are considered in relation to the development of potential agents for the treatment of patients with colon cancer. Regulatory pathways that influence Wnt signaling highlight how it might be possible to design therapies that target a network of signals beyond that of APC and β-catenin.

Identification of a gene-expression signature for predicting lymph node metastasis in patients with early stage cervical carcinoma

BACKGROUND

Pelvic lymph node metastasis (PLNM) is an important prognostic factor for patients with cervical carcinoma. The objective of this study was to identify a gene-expression signature that could predict PLNM in cervical carcinoma.

METHODS

Eighty-eight women with cervical carcinoma with PLNM (n = 23) and without PLNM (n = 65) were divided randomly into a training group and a test group. An oligonucleotide microarray that contained probes for 1440 human cancer-related genes was fabricated in-house and was used to detect the gene expression profile of cervical carcinoma. The gene expression levels detected in the microarray were verified by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR).

RESULTS

A gene-expression signature for predicting PLNM was developed in patients from the training group, including 11 genes: ribosomal protein L35 (RPL35); thymosin β 10 (TMSB10); tyrosine 3-mono-oxytenase/tryptophan 5-mono-oxygenase activation protein, ζ polypeptide (YWHAZ); biotinidase (BTD); lactate dehydrogenase A (LDHA); glucuronidase β (GUSB); superoxide dismutase 2 (SOD2); nuclear receptor subfamily 3, group C, member 2 (NR3C2); fructosamine 3 kinase (FN3K); x-ray repair cross-complementing 4 (XRCC4); and wingless-type mouse mammary tumor virus integration site family member 2 (WNT2). In the test group, the signature's accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 91%, 90.9%, 93.9%, 83.3%, and 96.9%, respectively, for predicting PLNM. The expression levels of 5 genes in the signature were confirmed by qRT-PCR. A multivariate analysis demonstrated that patients with 11-gene high-risk scores were had a 33-fold increased risk for PLNM compared with patients who had low-risk scores. The 5-year overall and disease-free survival rates for patients who had 11-gene high-risk scores were marginally significantly lower than the rates for patients who had 11-gene low-risk scores (P = .087 and P = .174, respectively).

CONCLUSIONS

In this study, 11-gene signature for predicting PLNM in cervical carcinoma was identified that may help clinicians in planning therapy for patients with cervical carcinoma.

Hear the Wnt Ror: how melanoma cells adjust to changes in Wnt

The interplay between canonical and non-canonical Wnt pathways in development and tumorigenesis is tightly regulated. In this review we will describe the yin and the yang of canonical and non-canonical Wnt signaling pathways during melanocyte development, and melanoma genesis. Canonical Wnt signaling, represented by Wnts such as Wnt1 and Wnt3A, signals via beta-catenin to promote melanocyte differentiation and tumor development. Non-canonical Wnt signaling, specifically Wnt5A, regulates canonical pathways, and signals to induce melanoma metastasis. This review will focus on the role of Wnt5A during melanoma progression, and its relationship to canonical Wnt signaling.