WNT5A exhibits tumor-suppressive activity through antagonizing the Wnt/beta-catenin signaling, and is frequently methylated in colorectal cancer

The Interplay among Wnt/β-catenin Family Members in Colorectal Adenomas and Surrounding Tissues

BACKGROUND

The colorectal adenoma undergoes neoplastic progression via the normal epithelium-adenoma-adenocarcinoma sequence as reported in the Vogelgram. The hazard of developing a tumor is deeply associated with the number and size of adenomas and their subtype. Adenomatous polyps are histologically categorized as follows: approximately 80-90% are tubular, 5-15% are villous, and 5-10% are tubular/villous. Given the higher risk of a malignant transformation observed in tubular/villous adenomas, patients diagnosed with adenomatous polyposis are at an improved risk of developing CRC. The Wnt/β-catenin pathway plays a key role in the onset of colorectal adenoma; in particular, intestinal cells first acquire loss-of-function mutations in the APC gene that induce the formation of adenomas.

METHODS

Wnt/β-catenin pathway APC, Wnt3a, Wnt5a, LEF1, and BCL9 genes and protein expression analyses were conducted by qRT-PCR and western blot in 68 colonic samples (polyps and adjacent mucosa) from 41 patients, of which 17 were affected by FAP. Ten normal colonic mucosal samples were collected from 10 healthy donors.

RESULTS

In this study, both the APC gene and protein were less expressed in the colon tumor compared to the adjacent colonic mucosa. Conversely, the activated β-catenin was more expressed in polyps than in the adjacent mucosa. All results confirmed the literature data on carcinomas. A statistically significant correlation between Wnt3a and BCL9 both in polyps and in the adjacent mucosa underlines that the canonical Wnt pathway is activated in early colon carcinogenesis and that the adjacent mucosa is already altered.

CONCLUSION

This is the first study analyzing the difference in expression of the Wnt/β-catenin pathway in human colorectal adenomas. Understanding the progression from adenomas to colorectal carcinomas is essential for the development of new therapeutic strategies and improving clinical outcomes with the use of APC and β-catenin as biomarkers.

WNT5A is a putative epi-driver of prostate cancer metastasis to the bone

BACKGROUND

Current diagnostic tools are unable to distinguish low-grade indolent prostate cancer (PrCa) from that with a propensity to become metastatic and/or lethal. Recent evidence suggests that reprogramming of the transcriptome may drive the metastatic phenotype, and that this reprogramming is controlled, at least in part, by epigenetic changes to the DNA of cancer cells, including methylation. These changes, referred to as 'epigenetic drivers,' have previously been associated with cancer cell survival.

METHODS

Here, using Illumina Methylation EPIC array data of paired primary PrCa and metastatic bone samples, we identified WNT5A as a putative epi-driver of PrCa metastasis to the bone, which was further validated in vitro.

RESULTS

Significantly higher WNT5A methylation was observed in primary PrCa samples and 22Rv1 cells compared to metastatic bone samples and PC-3 cells. This higher methylation was associated with significantly lower WNT5A gene expression.

CONCLUSION

Given the limited effective therapies available for metastatic cancer sufferers, particularly those whose disease has metastasised to the bone, WNT5A presents as a potential putative target for therapy.

Unraveling Cancer's Wnt Signaling: Dynamic Control through Protein Kinase Regulation

Since the initial identification of oncogenic Wnt in mice and Drosophila, the Wnt signaling pathway has been subjected to thorough and extensive investigation. Persistent activation of Wnt signaling exerts diverse cancer characteristics, encompassing tumor initiation, tumor growth, cell senescence, cell death, differentiation, and metastasis. Here we review the principal signaling mechanisms and the regulatory influence of pathway-intrinsic and extrinsic kinases on cancer progression. Additionally, we underscore the divergences and intricate interplays of the canonical and non-canonical Wnt signaling pathways and their critical influence in cancer pathophysiology, exhibiting both growth-promoting and growth-suppressing roles across diverse cancer types.

Wnt/β-catenin signaling pathway in carcinogenesis and cancer therapy

The Wnt/β-catenin signaling pathway plays a crucial role in various physiological processes, encompassing development, tissue homeostasis, and cell proliferation. Under normal physiological conditions, the Wnt/β-catenin signaling pathway is meticulously regulated. However, aberrant activation of this pathway and downstream target genes can occur due to mutations in key components of the Wnt/β-catenin pathway, epigenetic modifications, and crosstalk with other signaling pathways. Consequently, these dysregulations contribute significantly to tumor initiation and progression. Therapies targeting the Wnt/β-catenin signaling transduction have exhibited promising prospects and potential for tumor treatment. An increasing number of medications targeting this pathway are continuously being developed and validated. This comprehensive review aims to summarize the latest advances in our understanding of the role played by the Wnt/β-catenin signaling pathway in carcinogenesis and targeted therapy, providing valuable insights into acknowledging current opportunities and challenges associated with targeting this signaling pathway in cancer research and treatment.

miR-139-3p/Wnt5A Axis Inhibits Metastasis in Hepatoblastoma

In order to examine new potential treatment options for the treatment of hepatoblastoma (HB), we identified the differential expression of five-candidate tumor suppressor miRNAs in HB and explored possible regulatory mechanisms of target miRNA molecule. By using real-time quantitative polymerase chain reaction (qPCR), we examined the expression of miRNAs in HB tissues and cells. The effect of has-miR-139-3p mimics on the invasion and migration ability was assessed by transwell assay and scratch-wound assay in HepG2 cells. Subsequently, we analyzed the target genes of miR-139-3p and their enrichment signaling pathways through bioinformatics. qPCR, Western-blot and dual-luciferase assays were further used to assess whether has-miR-139-3p targets Wnt5A. The results showed that hsa-miR-139-3p was significantly decreased in HB cells. Upregulation of hsa-miR-139-3p inhibited the invasive and migratory ability of HepG2. Bioinformatics analysis showed that hsa-miR-139-3p may target Wnt5A to regulate the WNT pathway, which was further confirmed by Western-blot and dual-luciferase assays. Overexpression of Wnt5A can reverse the miR-139-3p mimic-induced declines in the expression of WNT pathway-related proteins and restore the invasion and migration of HepG2. These data indicated that the hsa-miR-139-3p/Wnt5A axis inhibited HB metastasis, suggesting that miR-139-3p and Wnt5A may be potential targets for the treatment of HB.

LGR5 Expression Predicting Poor Prognosis Is Negatively Correlated with WNT5A in Colon Cancer

WNT/β-catenin signaling is essential for colon cancer development and progression. WNT5A (ligand of non-canonical WNT signaling) and its mimicking peptide Foxy5 impair β-catenin signaling in colon cancer cells via unknown mechanisms. Therefore, we investigated whether and how WNT5A signaling affects two promoters of β-catenin signaling: the LGR5 receptor and its ligand RSPO3, as well as β-catenin activity and its target gene VEGFA. Protein and gene expression in colon cancer cohorts were analyzed by immunohistochemistry and qRT-PCR, respectively. Three colon cancer cell lines were used for in vitro and one cell line for in vivo experiments and results were analyzed by Western blotting, RT-PCR, clonogenic and sphere formation assays, immunofluorescence, and immunohistochemistry. Expression of WNT5A (a tumor suppressor) negatively correlated with that of LGR5/RSPO3 (tumor promoters) in colon cancer cohorts. Experimentally, WNT5A signaling suppressed β-catenin activity, LGR5, RSPO3, and VEGFA expression, and colony and spheroid formations. Since β-catenin signaling promotes colon cancer stemness, we explored how WNT5A expression is related to that of the cancer stem cell marker DCLK1. DCLK1 expression was negatively correlated with WNT5A expression in colon cancer cohorts and was experimentally reduced by WNT5A signaling. Thus, WNT5A and Foxy5 decrease LGR5/RSPO3 expression and β-catenin activity. This inhibits stemness and VEGFA expression, suggesting novel treatment strategies for the drug candidate Foxy5 in the handling of colon cancer patients.

Mutant APC reshapes Wnt signaling plasma membrane nanodomains by altering cholesterol levels via oncogenic β-catenin

Although the role of the Wnt pathway in colon carcinogenesis has been described previously, it has been recently demonstrated that Wnt signaling originates from highly dynamic nano-assemblies at the plasma membrane. However, little is known regarding the role of oncogenic APC in reshaping Wnt nanodomains. This is noteworthy, because oncogenic APC does not act autonomously and requires activation of Wnt effectors upstream of APC to drive aberrant Wnt signaling. Here, we demonstrate the role of oncogenic APC in increasing plasma membrane free cholesterol and rigidity, thereby modulating Wnt signaling hubs. This results in an overactivation of Wnt signaling in the colon. Finally, using the Drosophila sterol auxotroph model, we demonstrate the unique ability of exogenous free cholesterol to disrupt plasma membrane homeostasis and drive Wnt signaling in a wildtype APC background. Collectively, these findings provide a link between oncogenic APC, loss of plasma membrane homeostasis and CRC development.

WNT5A: a double-edged sword in colorectal cancer progression

The Wnt signaling pathway is known to play a crucial role in cancer, and WNT5A is a member of this pathway that binds to the Frizzled (FZD) and Receptor Tyrosine Kinase-Like Orphan Receptor (ROR) family members to activate non-canonical Wnt signaling pathways. The WNT5A pathway is involved in various cellular processes, such as proliferation, differentiation, migration, adhesion, and polarization. In the case of colorectal cancer (CRC), abnormal activation or inhibition of WNT5A signaling can lead to both oncogenic and antitumor effects. Moreover, WNT5A is associated with inflammation, metastasis, and altered metabolism in cancer cells. This article aims to discuss the molecular mechanisms and dual roles of WNT5A in CRC.

The Roles of Secreted Wnt Ligands in Cancer

Wnt ligands are secreted signaling proteins that display a wide range of biological effects. They play key roles in stimulating Wnt signaling pathways to facilitate processes such as tissue homeostasis and regeneration. Dysregulation of Wnt signaling is a hallmark of many cancers and genetic alterations in various Wnt signaling components, which result in ligand-independent or ligand-dependent hyperactivation of the pathway that have been identified. Recently, research is focusing on the impact of Wnt signaling on the interaction between tumor cells and their micro-environment. This Wnt-mediated crosstalk can act either in a tumor promoting or suppressing fashion. In this review, we comprehensively outline the function of Wnt ligands in different tumor entities and their impact on key phenotypes, including cancer stemness, drug resistance, metastasis, and immune evasion. Lastly, we elaborate approaches to target Wnt ligands in cancer therapy.

SEL1L-HRD1 ER-associated degradation suppresses hepatocyte hyperproliferation and liver cancer

Endoplasmic reticulum (ER) homeostasis has been implicated in the pathogenesis of various forms of cancer; however, our understanding of the role of ER quality control mechanisms in tumorigenesis remains incomplete. Here, we show that the SEL1L-HRD1 complex of ER-associated degradation (ERAD) suppresses hepatocyte proliferation and tumorigenesis in mice. Hepatocyte-specific deletion of Sel1L or Hrd1 predisposed mice to diet/chemical-induced tumors. Proteomics screen from SEL1L-deficient livers revealed WNT5A, a tumor suppressor, as an ERAD substrate. Indeed, nascent WNT5A was misfolding prone and degraded by SEL1L-HRD1 ERAD in a quality control capacity. In the absence of ERAD, WNT5A misfolds is largely retained in the ER and forms high-molecular weight aggregates, thereby depicting a loss-of-function effect and attenuating WNT5A-mediated suppression of hepatocyte proliferation. In humans, SEL1L-HRD1 ERAD expression correlated positively with survival time for patients with liver cancer. Overall, our data reveal a key role of SEL1L-HRD1 ERAD in suppressing hepatocyte proliferation and liver cancer.

Tumor suppressive functions of WNT5A in rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is a highly aggressive soft tissue malignancy that predominantly affects children. The main subtypes are alveolar RMS (ARMS) and embryonal RMS (ERMS) and the two show an impaired muscle differentiation phenotype. One pathway involved in muscle differentiation is WNT signaling. However, the role of this pathway in RMS is far from clear. Our recent data showed that the canonical WNT/β-Catenin pathway serves a subordinate role in RMS, whereas non-canonical WNT signaling probably is more important for this tumor entity. The present study investigated the role of WNT5A, which is the major ligand of non-canonical WNT signaling, in ERMS and ARMS. Gene expression analysis showed that WNT5A was expressed in human RMS samples and that its expression is more pronounced in ERMS. When stably overexpressed in RMS cell lines, WNT5A decreased proliferation and migration of the cells as demonstrated by BrdU incorporation and Transwell migration or scratch assay, respectively. WNT5A also decreased the self-renewal capacity and the expression of stem cell markers and modulates the levels of muscle differentiation markers as shown by sphere assay and western blot analysis, respectively. Finally, overexpression of WNT5A can destabilize active β-Catenin of RMS cells. A WNT5A knockdown has opposite effects. Together, the results suggest that WNT5A has tumor suppressive functions in RMS, which accompanies downregulation of β-Catenin.

Memory B-cell like chronic lymphocytic leukaemia is associated with specific methylation profile of WNT5A promoter and undetectable expression of WNT5A gene

Genome methylation profiles define naïve-like (n-CLL), memory-like (m-CLL), and intermediate (i-CLL) subsets of chronic lymphocytic leukaemia (CLL). The profiles can be easily determined by the analysis of the five-CpG signature. m-CLL, i-CLL, and n-CLL with the good, intermediate, and poor prognoses, respectively, differ by the somatic hypermutation status of the immunoglobulin heavy chain variable gene (IGHV), a widely used prognostic predictor in CLL. We have previously shown that the expression of WNT5A, encoding a ROR1 ligand, distinguishes patients with the worse outcome within the prognostically favourable IGHV-mutated subgroup. To analyse the mechanisms controlling WNT5A expression, we investigated the methylation status of 54 CpG sites within the WNT5A promoter and its relation to the WNT5A gene expression. In a cohort of 59 CLL patients balanced for combinations of IGHV and WNT5A statuses, we identified three promoter CpG sites whose methylation level correlated with the WNT5A expression within the IGHV-mutated subgroup. Further, we complemented our data with the methylation status of the five-CpG signature. IGHV-mutated/WNT5A-negative and IGHV-mutated/WNT5A-positive cases overlapped with m‑CLL and i‑CLL methylation subgroups, respectively, while most IGHV‑unmutated samples were assigned to n-CLL. Median methylation levels of all the three CpG sites in the WNT5A promoter were lowest in i-CLL. Finally, a detailed analysis of m-CLL and i-CLL showed that undetectable WNT5A expression predicts longer treatment-free survival with higher statistical significance than the classification according to the five-CpG signature. To conclude, a favourable m-CLL subgroup is associated with mutated IGHV and undetectable WNT5A expression due to its promoter methylation.

Fisetin alleviates thioacetamide-induced hepatic fibrosis in rats by inhibiting Wnt/β-catenin signaling pathway

BACKGROUND

Liver fibrosis is a chronic wound-healing response to liver injury of various origins and represents a major health problem.

OBJECTIVE

The current study endeavored to investigate the repressing effect of fisetin on hepatic fibrosis induced by thioacetamide (TAA) in rats.

MATERIALS AND METHODS

Rats were injected with TAA (200 mg/kg) intraperitoneally twice per week for 6 weeks to induce liver fibrosis. Fisetin (50 and 100 mg/kg/day) or silymarin (50 mg/kg/day) were given orally on a daily basis along with TAA. Liver function parameters, oxidative stress, inflammatory and fibrogenic biomarkers as well as wnt3a, β-catenin, glycogen synthase kinase 3 (GSK-3β) and cyclin D1 were estimated. Histoapthological and immunohistochemical examinations were performed.

RESULTS

Fisetin restored normal liver functions, increased reduced glutathione (GSH) level and decreased malondialdehyde (MDA), as well as inflammatory biomarkers including; tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6). Additionally, it lessened transforming growth factor β1 (TGF-β1), collagen I and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels as well as elevated matrix metalloproteinase-9 (MMP-9) hepatic content. Furthermore, fisetin significantly suppressed wnt3a gene expression associated with decreased β-catenin and increased GSK-3β levels. Moreover, fisetin decreased the progress of histologic hepatic fibroplasia and diminished hepatic expression of α-SMA and cyclin D1.

CONCLUSION

Fisetin curbed liver fibrosis and exhibited superior activity over silymarin through inhibition of hepatic stellate cells (HSCs) activation and proliferation via suppressing the Wnt/β-catenin pathway, modulating MMP-9 and TIMP-1, and inhibiting multiple profibrogenic factors, besides its antioxidant and anti-inflammatory effects. Therefore, fisetin is a promising therapeutic candidate for hepatic fibrosis.

NSAIDs and Cancer Resolution: New Paradigms beyond Cyclooxygenase

Acute inflammation or resolved inflammation is an adaptive host defense mechanism and is self-limiting, which returns the body to a state of homeostasis. However, unresolved, uncontrolled, or chronic inflammation may lead to various maladies, including cancer. Important evidence that links inflammation and cancer is that nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, reduce the risk and mortality from many cancers. The fact that NSAIDs inhibit the eicosanoid pathway prompted mechanistic drug developmental work focusing on cyclooxygenase (COX) and its products. The increased prostaglandin E2 levels and the overexpression of COX-2 in the colon and many other cancers provided the rationale for clinical trials with COX-2 inhibitors for cancer prevention or treatment. However, NSAIDs do not require the presence of COX-2 to prevent cancer. In this review, we highlight the effects of NSAIDs and selective COX-2 inhibitors (COXIBs) on targets beyond COX-2 that have shown to be important against many cancers. Finally, we hone in on specialized pro-resolving mediators (SPMs) that are biosynthesized locally and, in a time, -dependent manner to promote the resolution of inflammation and subsequent tissue healing. Different classes of SPMs are reviewed, highlighting aspirin's potential in triggering the production of these resolution-promoting mediators (resolvins, lipoxins, protectins, and maresins), which show promise in inhibiting cancer growth and metastasis.

Prognostic role of oxytocin receptor in colon adenocarcinoma

The oxytocin receptor (OXTR) is directly involved in the pathological mechanisms of multiple cancers, including breast cancer, prostate cancer, and ovarian cancer; however, the role of OXTR in the modulation of colon adenocarcinoma (COAD) growth, metastasis, and clinical prognosis remains to be elucidated. This study used systematic bioinformatics analysis to explore the effects of OXTR on modulating COAD growth and prognosis in patients with COAD. Compared with normal tissues, OXTR mRNA level was higher in COAD tissues, which was associated with tumor progression. Elevated mRNA level of OXTR also indicated a poor prognosis in COAD patients. Furthermore, high mRNA level of OXTR was significantly associated with pathways involved in cell cycle regulation and signal transduction pathways, including the hedgehog, mTOR, TGF-β, and Wnt signaling pathways. OXTR expression was significantly correlated with the infiltration level of type 2T helper cell, central memory CD8 T cell, CD56 bright natural killer cell, activated CD8 T cell, activated B cell, and Type 1T helper cell. Moreover, silencing OXTR inhibited cell proliferation, migration, and invasion, and arrested the cell cycle. In conclusion, high mRNA level of OXTR indicates poor prognosis.

ROR2 has a protective role in melanoma by inhibiting Akt activity, cell-cycle progression, and proliferation

BACKGROUND

Receptor tyrosine kinase-like orphan receptor 2 (ROR2) is a Wnt5a receptor aberrantly expressed in cancer that was shown to either suppress or promote carcinogenesis in different tumor types. Our goal was to study the role of ROR2 in melanoma.

METHODS

Gain and loss-of-function strategies were applied to study the biological function of ROR2 in melanoma. Proliferation assays, flow cytometry, and western blotting were used to evaluate cell proliferation and changes in expression levels of cell-cycle and proliferation markers. The role of ROR2 in tumor growth was assessed in xenotransplantation experiments followed by immunohistochemistry analysis of the tumors. The role of ROR2 in melanoma patients was assessed by analysis of clinical data from the Leeds Melanoma Cohort.

RESULTS

Unlike previous findings describing ROR2 as an oncogene in melanoma, we describe that ROR2 prevents tumor growth by inhibiting cell-cycle progression and the proliferation of melanoma cells. The effect of ROR2 is mediated by inhibition of Akt phosphorylation and activity which, in turn, regulates the expression, phosphorylation, and localization of major cell-cycle regulators including cyclins (A, B, D, and E), CDK1, CDK4, RB, p21, and p27. Xenotransplantation experiments demonstrated that ROR2 also reduces proliferation in vivo, resulting in inhibition of tumor growth. In agreement with these findings, a higher ROR2 level favors thin and non-ulcerated primary melanomas with reduced mitotic rate and better prognosis.

CONCLUSION

We conclude that the expression of ROR2 slows down the growth of primary tumors and contributes to prolonging melanoma survival. Our results demonstrate that ROR2 has a far more complex role than originally described.

Bridging the gap between non-canonical and canonical Wnt signaling through Vangl2

Non-canonical Wnt signaling (encompassing Wnt/PCP and WntCa²⁺) has a dual identity in the literature. One stream of research investigates its role in antagonizing canonical Wnt/β-catenin signaling in cancer, typically through Ca²⁺, while the other stream investigates its effect on polarity in development, typically through Vangl2. Rarely do these topics intersect or overlap. What has become clear is that Wnt5a can mobilize intracellular calcium stores to inhibit Wnt/β-catenin in cancer cells but there is no evidence that Vangl2 is involved in this process. Conversely, Wnt5a can independently activate Vangl2 to affect polarity and migration but the role of calcium in this process is also limited. Further, Vangl2 has also been implicated in inhibiting Wnt/β-catenin signaling in development. The consensus is that a cell can differentiate between canonical and non-canonical Wnt signaling when presented with a choice, always choosing non-canonical at the expense of canonical Wnt signaling. However, these are rare events in vivo. Given the shared resources between non-canonical and canonical Wnt signaling it is perplexing that there is not more in vivo evidence for cross talk between these two pathways. In this review we discuss the intersection of non-canonical Wnt, with a focus on Wnt/PCP, and Wnt/β-catenin signaling in an attempt to shed some light on pathways that rarely meet at a crossroads in vivo.

Clinical Importance of Wnt5a in the Pathogenesis of Colorectal Cancer

Wnt5a is one of the potent signaling molecules that initiates responses involved in cancer through activation of both canonical and noncanonical signaling cascades. Wnt5a both directly and indirectly triggers cancer-associated signaling pathways based on the cancer type. In colorectal cancer (CRC), altering Wnt5a expression can influence several cellular processes of tumor cells, including proliferation, differentiation, migration, invasion, and metastasis. This review summarizes the molecular mechanisms and clinical importance of Wnt5a in the pathogenesis of CRC for better understanding the pathogenesis and its potential role as a prognostic marker and as an appropriate therapeutic target in the treatment of this disease in the future.

Epigenetic Regulation of the Wnt/β-Catenin Signaling Pathway in Cancer

Studies over the past four decades have elucidated the role of Wnt/β-catenin mediated regulation in cell proliferation, differentiation and migration. These processes are fundamental to embryonic development, regeneration potential of tissues, as well as cancer initiation and progression. In this review, we focus on the epigenetic players which influence the Wnt/β-catenin pathway via modulation of its components and coordinated regulation of the Wnt target genes. The role played by crosstalk with other signaling pathways mediating tumorigenesis is also elaborated. The Hippo/YAP pathway is particularly emphasized due to its extensive crosstalk via the Wnt destruction complex. Further, we highlight the recent advances in developing potential therapeutic interventions targeting the epigenetic machinery based on the characterization of these regulatory networks for effective treatment of various cancers and also for regenerative therapies.

Embryonic Stem Cell Differentiation Is Regulated by SET through Interactions with p53 and β-Catenin

The multifunctional histone chaperone, SET, is essential for embryonic development in the mouse. Previously, we identified SET as a factor that is rapidly downregulated during embryonic stem cell (ESC) differentiation, suggesting a possible role in the maintenance of pluripotency. Here, we explore SET's function in early differentiation. Using immunoprecipitation coupled with protein quantitation by LC-MS/MS, we uncover factors and complexes, including P53 and β-catenin, by which SET regulates lineage specification. Knockdown for P53 in SET-knockout (KO) ESCs partially rescues lineage marker misregulation during differentiation. Paradoxically, SET-KO ESCs show increased expression of several Wnt target genes despite reduced levels of active β-catenin. Further analysis of RNA sequencing datasets hints at a co-regulatory relationship between SET and TCF proteins, terminal effectors of Wnt signaling. Overall, we discover a role for both P53 and β-catenin in SET-regulated early differentiation and raise a hypothesis for SET function at the β-catenin-TCF regulatory axis.

Colorectal cancer risk variant rs7017386 modulates two oncogenic lncRNAs expression via ATF1-mediated long-range chromatin loop

The activating transcription factor 1 (ATF1) has been identified as a vital pathogenic factor in the progression of colorectal cancer (CRC), whiles, the precise regulatory mechanisms remain elusive. Here, we comprehensively characterized the ATF1 cistrome by RNA-seq and ChIP-seq assays in CRC cell lines. As the results, we identified 358 genes differentially regulated and 15,029 ATF1 binding sites and demonstrated that ATF1 was widely involved in major signaling pathways in CRC, such as Wnt, TNF, Jak-STAT. Subsequently, by the expression quantitative trait loci (eQTL) analyses, we found that rs7017386 was associated with the expression of CCAT1 and PVT1 in the Wnt pathway. By a two-stage population study with 6,131 CRC cases and 10,022 healthy controls, we identified the variant was associated with CRC risk. Mechanistically, we found rs7017386 allele-specifically enhanced the binding affinity of ATF1 and promoted the expressions of PVT1 and CCAT1, via forming a long-range chromatin loop. Moreover, those two lncRNAs could synergistically facilitate c-Myc expression to activate the Wnt pathway in CRC progression. Our findings not only demonstrated the transcriptomic profiling of ATF1 in CRC, but also provided important clues for the etiology of CRC.

Wnt5a in cancer-associated fibroblasts promotes colorectal cancer progression

Cancer-associated fibroblasts (CAFs) are a major component of the tumor microenvironment and have been shown to promote cancer aggressiveness. In our previous study, analysis of expression profiles obtained from paired CAFs and normal fibroblasts from colorectal cancer (CRC) tissue revealed that gene sets related to the Wnt signaling pathway were highly enriched in colorectal CAFs. Furthermore, among the components of the β-catenin-independent Wnt pathway, Wnt5a was highly expressed in CAFs. Since Wnt5a is considered to be a regulator of CRC progression in CAFs, we performed immunohistochemical analysis on Wnt5a in 171 patients who underwent surgery for CRC. Positive staining for Wnt5a was often found in cancer stroma, particularly in fibromatous areas, although the immunoreactivity for Wnt5a was weak in cancer cells. Wnt5a status in CAFs was significantly associated with tumor size, depth of invasion, lymphatic and vascular invasion, lymph node metastasis, TNM stage, and recurrence. Subsequent in vitro analyses using human recombinant Wnt5a protein revealed that cancer cell proliferation and migration were significantly increased by stimulation with Wnt5a. Our findings suggest that Wnt5a-derived CAFs play a crucial role in CRC progression and have potential as a target of anti-cancer therapies.

Mucosal ribosomal stress-induced PRDM1 promotes chemoresistance via stemness regulation

The majorities of colorectal cancer (CRC) cases are sporadic in origin and a large proportion of etiologies are associated with environmental stress responses. In response to external and internal stress, the ribosome stands sentinel and stress-driven ribosomal dysfunction triggers the cellular decision pathways via transcriptional reprogramming. In the present study, PR domain zinc finger protein (PRDM) 1, a master transcriptional regulator, was found to be closely associated with ribosomal actions in patients with CRC and the murine models. Stress-driven ribosomal dysfunction enhanced PRDM1 levels in intestinal cancer cells, which contributed to their survival and enhanced cancer cell stemness against cancer treatment. Mechanistically, PRDM1 facilitated clustering modulation of insulin-like growth factor (IGF) receptor-associated genes, which supported cancer cell growth and stemness-linked features. Ribosomal dysfunction-responsive PRDM1 facilitated signaling remodeling for the survival of tumor progenitors, providing compelling evidence for the progression of sporadic CRC.

WNT5a in Colorectal Cancer: Research Progress and Challenges

Despite the clinical development of new adjuvant and neoadjuvant chemotherapy drugs, colorectal cancer is still one of the leading causes of cancer-related death in human beings. WNT5a, an autocrine and paracrine β-catenin independent ligand, has been shown to induce tumor inhibition and carcinogenic signals, depending on the type of cancer. In patients with colorectal cancer, WNT5a triggers a variety of downstream signaling pathways, which mainly affect the migration and invasion of tumor cells. This article reviews the mechanism and therapeutic potential of WNT5a in colorectal cancer. In short, an in-depth understanding of the role of WNT5a in colorectal cancer is very helpful to better deal with this disease.

High stroma-derived WNT5A is an indicator for low-risk prostate cancer

Prostate cancer (PCa) is a major cause of cancer‐related death in men. Tumor‐derived protein derived from Wnt5A gene (WNT5A) plays an important role in primary and metastatic PCa. Surrounding stroma cells also produce WNT5A, which may modulate the biology of PCa. Here, we assessed the role of stroma‐derived WNT5A (stWNT5A) in primary PCa. A tissue microarray of samples obtained from 400 patients who underwent radical prostatectomy and control samples from 41 patients with benign prostate hyperplasia (BPH) was immunohistochemically assessed for expression of stWNT5A. The cores were scored for staining intensity: 0 (no staining), 1 (weak), 2 (moderate), or 3 (strong) and the stained stromal surface area: 0 (0%), 1 (1–25%), 2 (26–50%), 3 (51–75%), or 4 (76–100%). Gleason Score (GS) and TNM‐stage were assessed by stratifying the cohort into high‐risk (≥ pT3, pN1, GS ≥ 8) and non‐high‐risk patients. Ki67 and TUNEL assays were performed to assess proliferation and apoptosis. Expression of stWNT5A in BPH and tumor‐free control samples was 1.2‐fold higher compared to tumor samples (P < 0.001). Non‐high‐risk patients had a higher stWNT5A score than high‐risk patients (P < 0.05). stWNT5A expression was not correlated with overall and cancer‐specific survival. Proliferation (r² = 0.038, P < 0.001) and apoptosis (r² = 0.277, P < 0.001) negatively correlated with stWNT5A expression. In summary, we show that expression of stWNT5A is higher in benign tissue and non‐high‐risk PCa. Stroma‐derived Wnt signaling and tumor‐derived Wnt may differentially impact on tumor behavior. Future studies are warranted to dissect the Wnt profile in tumor vs. surrounding stroma tissues.

Targeting Oncogenic WNT Signalling with WNT Signalling-Derived Peptides

WNT signalling is known to be a crucial regulator of embryonic development and tissue homeostasis. Aberrant expression of WNT signalling elements or their mutations has been implicated in carcinogenesis and/or the progression of several different cancer types. Investigations of how WNT signalling affects carcinogenesis and cancer progression have revealed that it has essential roles in the regulation of proliferation, apoptosis, and cancer stemness and in angiogenesis and metastasis. Consequently, WNT-targeted therapy has gained much attention and has resulted in the development of several small molecules, the majority of which act as inhibitors of different WNT signalling events. However, although numerous inhibitory WNT signalling drug candidates have been included in clinical trials, no significant breakthroughs have been made. This could possibly be due to problems with inefficient binding to the target, compensatory signalling mechanisms and toxicity towards normal cells. Therapeutic peptides targeting WNT signalling in cancer cells have been developed as an alternative approach, with the hope that they might overcome the limitations reported for small WNT inhibitory molecules. In this chapter, we describe recent developments made in the design and characterization of WNT signalling-derived peptides aiming at their use as alternative cancer therapeutics and/or combined adjuvant therapy to conventional therapies.

Wnt/β‑catenin signaling: Causes and treatment targets of drug resistance in colorectal cancer (Review)

Colorectal cancer (CRC) is the third most common malignant tumor in humans. Chemotherapy is used for the treatment of CRC. However, the effect of chemotherapy remains unsatisfactory due to drug resistance. Growing evidence has shown that the presence of highly metastatic tumor stem cells, regulation of non-coding RNAs and the tumor microenvironment contributes to drug resistance mechanisms in CRC. Wnt/β-catenin signaling mediates the chemoresistance of CRC in these three aspects. Therefore, the present study analyzed the abundant evidence of the contribution of Wnt/β-catenin signaling to the development of drug resistance in CRC and discussed its possible role in improving the chemosensitivity of CRC, which may provide guidelines for its clinical treatment.

Wnt signaling in breast cancer: biological mechanisms, challenges and opportunities

Wnt signaling is a highly conserved signaling pathway that plays a critical role in controlling embryonic and organ development, as well as cancer progression. Genome-wide sequencing and gene expression profile analyses have demonstrated that Wnt signaling is involved mainly in the processes of breast cancer proliferation and metastasis. The most recent studies have indicated that Wnt signaling is also crucial in breast cancer immune microenvironment regulation, stemness maintenance, therapeutic resistance, phenotype shaping, etc. Wnt/β-Catenin, Wnt-planar cell polarity (PCP), and Wnt-Ca2+ signaling are three well-established Wnt signaling pathways that share overlapping components and play different roles in breast cancer progression. In this review, we summarize the main findings concerning the relationship between Wnt signaling and breast cancer and provide an overview of existing mechanisms, challenges, and potential opportunities for advancing the therapy and diagnosis of breast cancer.

Regulation of ABCG2 expression by Wnt5a through FZD7 in human pancreatic cancer cells

ATP-binding cassette subfamily G member 2 (ABCG2), a member of the ABC transporter superfamily, has been implicated in the development of chemotherapeutic drug resistance in cancer cells. However, the regulators of ABCG2 expression and their roles in anticancer drug resistance have not been fully characterized, especially in the context of pancreatic cancer. The aim of the present study was to investigate whether ABCG2 contributed to drug resistance in pancreatic cancer and to elucidate its regulatory molecular pathways. Using immunohistochemical analysis of pancreatic ductal adenocarcinoma and adjacent healthy tissue samples, the present study identified a positive correlation between ABCG2 and Wnt5a, a member of the Wnt family of secreted proteins. It was also determined that treatment with recombinant human Wnt5a protein could upregulate the expression of ABCG2 in the Capan-2 human pancreatic cancer cell line and enhance its resistance to gemcitabine. The upregulation of ABCG2 by Wnt5a was inhibited by small interfering RNA silencing of Frizzled class receptor 7 (FZD7) or by FZD7 inhibitors. Moreover, both FZD7 silencing or inhibition of its function attenuated gemcitabine resistance induced by Wnt5a in Capan-2 cells. Therefore, the present findings suggested that Wnt5a and FZD7 acted as upstream regulators of ABCG2 expression and that FZD7 may be an essential factor for Wnt5a-induced gemcitabine resistance in pancreatic cancer cells.

Wnt5a expression and prognosis in stage II-III colon cancer

Cancer metastases accounts for most cancer deaths. The secreting glycoprotein Wnt5a impairs tumor cell migration and reduces invasiveness and metastasis. High Wnt5a expression in tumor cells is correlated to better outcomes in patients with breast, prostate and epithelial ovarian cancer. We aimed to investigate the association between the Wnt5a expression and outcomes in patients with colon cancer (CC) stage II/III. We performed a retrospective single-center study evaluating 345 patients with radical resection for primary CC, stage II/III, who started 6 months of adjuvant chemotherapy with 5-FU or capecitabine ± oxaliplatin between 2001 and 2015. Archived formalin-fixed paraffin embedded tumor tissue from resection specimens were stained with Wnt5a antibody using immunohistochemistry. Cytoplasmatic Wnt5a staining was assessed according to intensity and percentage of stained cells. Patients were divided in groups depending on high (n = 230) or low (n = 115) Wnt5a expression. Disease free survival (DFS) and overall survival (OS) were analyzed for the two groups using Kaplan-Meier plots and Long rank test. Patients with Wnt5a-negative tumors had significantly poorer performance status (PS) than patients with high Wnt5a expression (p = 0.046). No significant difference was seen between patients with low and high Wnt5a expression in terms of 5-year DFS (p = 0.517) or 5-year OS (p = 0.415). Poor PS was associated with lower DFS (p = 0.002) and OS (p < 0.001). In conclusion, we found no significant difference in prognosis for patients with stage II/III CC depending on their Wnt5a expression. Patients with Wnt5a-negative tumors had significant poorer PS than patients with higher levels. Poor PS was associated with lower DFS and OS.

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High expression of Wnt5a in tumor cells are correlated to significantly better outcomes in patients with different cancers.

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We found no difference in survival among patients with colon cancer stage II-III depending on their Wnt5a expression.

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Patients with low Wnt5a expression had significantly poor performance status than patients with high levels.

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Poor performance status was shown to predict poorer outcomes.

Antioxidant Phytoconstituents From Onosma bracteata Wall. (Boraginaceae) Ameliorate the CCl4 Induced Hepatic Damage: In Vivo Study in Male Wistar Rats

Onosma bracteata Wall. (Boraginaceae) is a highly valuable medicinal herb that is used for the treatment of fever, bronchitis, asthma, rheumatism, stomach irritation, and other inflammatory disorders. The present study aims to explore the hepatoprotective potential of ethanolic extract (Obeth) from O. bracteata aerial parts against carbon tetrachloride (CCl₄) which causes hepatic damage in the male Wistar rats. Obeth showed effective radical quenching activity with an EC₅₀ of 115.14 and 199.33 µg/mL in superoxide radical scavenging and lipid peroxidation analyses respectively along with plasmid DNA protective potential in plasmid nicking assay. The Obeth modulated mutagenicity of 2 Aminofluorine (2AF) in the pre-incubation mode of investigation (EC₅₀ 10.48 µg/0.1 mL/plate) in TA100 strain of Salmonella typhimurium. In in vivo studies, pretreatment of Obeth (50, 100, and 200 mg/kg) had the potential to normalize the biochemical markers aggravated by CCl₄ (1mL/kg b.wt.) including liver antioxidative enzymes. Histopathological analysis also revealed the restoration of CCl₄-induced liver histopathological alterations. Immunohistochemical studies showed that the treatment of Obeth downregulated the expression levels of p53 and cyclin D in hepatocytes. and downregulation in the Western blotting analysis revealed the downregulation of p-NF-kB, COX-2, and p53. HPLC data analysis showed the supremacy of major compounds namely, catechin, kaempferol, epicatechin, and Onosmin A in Obeth. The present investigation establishes the hepatoprotective and chemopreventive potential of O. bracteata against CCl₄-induced hepatotoxicity via antioxidant defense system and modulation of the expression of proteins associated with the process of carcinogenesis in hepatic cells.

Detection of molecular signatures and pathways shared in inflammatory bowel disease and colorectal cancer: A bioinformatics and systems biology approach

Emerging evidence indicates IBD is a risk factor for the increasing incidence of colorectal cancer (CRC) development. We used a system biology approach to identify common molecular signatures and pathways that interact between IBD and CRC and the indispensable pathological mechanisms. First, we identified 177 common differentially expressed genes (DEGs) between IBD and CRC. Gene set enrichment, protein-protein, DEGs-transcription factors, DEGs-microRNAs, protein-drug interaction, gene-disease association, Gene Ontology, pathway enrichment analyses were conducted to these common genes. The inclusion of common DEGs with bimolecular networks disclosed hub proteins (LYN, PLCB1, NPSR1, WNT5A, CDC25B, CD44, RIPK2, ASAP1), transcription factors (SCD, SLC7A5, IKZF3, SLC16A1, SLC7A11) and miRNAs (mir-335-5p, mir-26b-5p, mir-124-3p, mir-16-5p, mir-192-5p, mir-548c-3p, mir-29b-3p, mir-155-5p, mir-21-5p, mir-15a-5p). Analysis of the interaction between protein and drug discovered ASAP1 interacts with cysteine sulfonic acid and double oxidized cysteine drug compounds. Gene-disease association analysis retrieved ASAP1 also associated with pulmonary and bladder neoplasm diseases.

Cancer Stem Cells: Devil or Savior-Looking behind the Scenes of Immunotherapy Failure

Although the introduction of immunotherapy has tremendously improved the prognosis of patients with metastatic cancers of different histological origins, some tumors fail to respond or develop resistance. Broadening the clinical efficacy of currently available immunotherapy strategies requires an improved understanding of the biological mechanisms underlying cancer immune escape. Globally, tumor cells evade immune attack using two main strategies: avoiding recognition by immune cells and instigating an immunosuppressive tumor microenvironment. Emerging data suggest that the clinical efficacy of chemotherapy or molecularly targeted therapy is related to the ability of these therapies to target cancer stem cells (CSCs). However, little is known about the role of CSCs in mediating tumor resistance to immunotherapy. Due to their immunomodulating features and plasticity, CSCs can be especially proficient at evading immune surveillance, thus potentially representing the most prominent malignant cell component implicated in primary or acquired resistance to immunotherapy. The identification of immunomodulatory properties of CSCs that include mechanisms that regulate their interactions with immune cells, such as bidirectional release of particular cytokines/chemokines, fusion of CSCs with fusogenic stromal cells, and cell-to-cell communication exerted by extracellular vesicles, may significantly improve the efficacy of current immunotherapy strategies. The purpose of this review is to discuss the current scientific evidence linking CSC biological, immunological, and epigenetic features to tumor resistance to immunotherapy.

The role of WNT5A and Ror2 in peritoneal membrane injury

Patients on peritoneal dialysis are at risk of developing peritoneal fibrosis and angiogenesis, which can lead to dysfunction of the peritoneal membrane. Recent evidence has identified cross‐talk between transforming growth factor beta (TGFB) and the WNT/β‐catenin pathway to induce fibrosis and angiogenesis. Limited evidence exists describing the role of non‐canonical WNT signalling in peritoneal membrane injury. Non‐canonical WNT5A is suggested to have different effects depending on the receptor environment. WNT5A has been implicated in antagonizing canonical WNT/β‐catenin signalling in the presence of receptor tyrosine kinase‐like orphan receptor (Ror2). We co‐expressed TGFB and WNT5A using adenovirus and examined its role in the development of peritoneal fibrosis and angiogenesis. Treatment of mouse peritoneum with AdWNT5A decreased the submesothelial thickening and angiogenesis induced by AdTGFB. WNT5A appeared to block WNT/β‐catenin signalling by inhibiting phosphorylation of glycogen synthase kinase 3 beta (GSK3B) and reducing levels of total β‐catenin and target proteins. To examine the function of Ror2, we silenced Ror2 in a human mesothelial cell line. We treated cells with AdWNT5A and observed a significant increase in fibronectin compared with AdWNT5A alone. We also analysed fibronectin and vascular endothelial growth factor (VEGF) in a TGFB model of mesothelial cell injury. Both fibronectin and VEGF were significantly increased in response to Ror2 silencing when cells were exposed to TGFB. Our results suggest that WNT5A inhibits peritoneal injury and this is associated with a decrease in WNT/β‐catenin signalling. In human mesothelial cells, Ror2 is involved in regulating levels of fibronectin and VEGF.

Emerging Roles of Wnt Ligands in Human Colorectal Cancer

Colorectal cancer (CRC) is the fourth leading cause of cancer death worldwide, and constitutive activation of the Wnt signaling pathway is universal in most CRC cases. Wnt ligands (Wnts) are secreted glycoproteins and fundamentally essential for the transduction of Wnt signaling pathway. However, the 19 members of Wnts in humans imply a daunting complexity of Wnt signaling and biological effects, and our understanding of their roles in CRC tumorigenesis is still quite rudimentary. This review will give an overview of the structural characteristics and maturation process of Wnts. The expression pattern of all human Wnts in CRC tissues, including Wnt1, Wnt2, Wnt2b, Wnt3, Wnt3a, Wnt4, Wnt5a, Wnt5b, Wnt6, Wnt7a, Wnt7b, Wnt8a, Wnt8b, Wnt9a, Wnt9b, Wnt10a, Wnt10b, Wnt11, and Wnt16, and their relationship with the tumorigenesis and the progression of CRC will be specifically summarized separately. Despite certain challenges, Wnt-based therapeutics for CRC emerge continuously and some are now in clinical trials. In conclusion, a deep understanding of Wnts is very helpful for a better management of this disease.

The diagnosis and prognosis values of WNT mRNA expression in colon adenocarcinoma

WNT family genes have participated in the progression and development of many cancers, however, the association between colon adenocarcinoma (COAD) and WNTs have been rarely reported. This study investigated the significance of WNT genes expression in COAD from the standpoint of diagnosis and prognosis. The RNA-sequencing dataset of COAD was downloaded from The Cancer Genome Atlas and University of California, Santa Cruz Xena browser. The biology functions of WNT genes were investigated by biological analysis. Biological analysis of WNT family genes indicated that WNT genes were noticeably enriched in the complex process of WNT signaling pathway. The Pearson correlation analysis suggested WNT1 and WNT9B had a strong correlation. And receiver operating characteristic curves suggested that most of the genes could serve as a significant diagnostic makers in COAD (P < .05), especially WNT2 and WNT7B had high diagnostic values that the area under curve were 0.997 (95% confidence interval [0.994-1.000]) and 0.961 (95%CI [0.939-0.983]), respectively. And our multivariate survival analysis suggested the downregulated of WNT10B (P < .05) showed a favor prognosis in COAD overall survival. And the risk score model predicted that the upregulated expression of WNT10B might increase the risk of death. The very study we had conducted suggested that WNT genes had a certain connection with the diagnosis and prognosis of COAD. The messenger RNA expression of WNT2 and WNT7B might become potentially diagnostic biomarkers, and WNT10B might serve as an independent prognosis indicator for COAD.

circCCT3 Modulates Vascular Endothelial Growth Factor A and Wnt Signaling to Enhance Colorectal Cancer Metastasis Through Sponging miR-613

Colorectal cancer (CRC) has been suggested to be one of the leading cancer types all over the world. Till now, the molecular mechanism by which circCCT3 regulates CRC remains to be clarified. To detect mRNA and protein levels of various genes, Reverse Transcription-quantitative PCR and western blot were used in our study. Luciferase reporter assay was utilized to probe direct interaction between genes. We used transwell assay to assess the invasion ability of CRC cells. For apoptosis detection, immunofluorescence of CRC cells by Annexin V staining was performed. We carried out bioinformatic analysis to show higher expression of circCCT3 in human clinical CRC tumors. Low level of circCCT3 was closely associated with higher disease-free survival of CRC patients. Moreover, we found that circCCT3 was linked to advanced stage of CRC. miR-613 is the target of circCCT3 and responsible for circCCT3-modulated invasion and apoptosis of CRC cells. In addition, we identified WNT3 and vascular endothelial growth factor A (VEGFA) as downstream effectors of miR-613 in CRC cells. WNT3 and VEGFA overexpression resulted in partial rescue of miR-613-mediated phenotypes of CRC cells. In conclusion, we propose that circCCT3 contributes to CRC metastasis via miR-613/WNT3 or miR-613/VEGFA, promoting the development of therapeutical approaches for treating CRC.

SNX3 suppresses the migration and invasion of colorectal cancer cells by reversing epithelial-to-mesenchymal transition via the β-catenin pathway

The Wnt/β-catenin signaling pathway is a well-studied pathway that drives the carcinogenesis and metastasis of colorectal cancer (CRC). The secretion of Wnt proteins is essential for the continuous activation of Wnt/β-catenin signaling in CRC. The secretion of Drosophila wingless, which is homologous to the human Wnt protein, is mediated by sorting nexin 3 (SNX3) in Drosophila; however, the role of SNX3 in CRC remains unknown. In the present study it was demonstrated that SNX3 reduced the migratory and invasive ability of HCT116 human CRC cells, and reversed epithelial-mesenchymal transition (EMT). Conversely, in the HT29 CRC cell line, which endogenously expresses high levels of SNX3, short hairpin RNA or siRNA-mediated knockdown of SNX3 induced EMT, and enhanced cell migration and invasion. In addition, upregulation of SNX3 significantly inhibited metastasis of HCT116 cells to the lungs of mice. These SNX3-mediated effects were associated with downregulation of β-catenin. Taken together, by downregulating β-catenin, SNX3 may mediate EMT and reverse CRC metastasis.

Wnt-11 as a Potential Prognostic Biomarker and Therapeutic Target in Colorectal Cancer

The expression of the secreted factor Wnt-11 is elevated in several types of cancer, including colorectal cancer, where it promotes cancer cell migration and invasion. Analysis of colorectal cancer gene expression databases associated WNT11 mRNA expression with increased likelihood of metastasis in a subset of patients. WNT11 expression was correlated with the expression of the Wnt receptors FZD6, RYK, and PTK7, and the combined expression of WNT11, FZD6 and RYK or PTK7 was associated with an increased risk of 5-year mortality rates. Immunohistochemical analysis of Wnt-11 in a cohort of 357 colorectal cancer patients found significantly higher Wnt-11 levels in tumors, compared with benign tissue. Elevated Wnt-11 levels occurred more frequently in rectal tumors than in colonic tumors and in tumors from women than men. In univariate analysis, increased Wnt-11 expression was also associated with tumor invasion and increased 5-year mortality. High Wnt-11 levels were not associated with high levels of nuclear β-catenin, suggesting Wnt-11 is not simply an indicator for activation of β-catenin-dependent signaling. Expression of Wnt-11 in colorectal cancer cell lines expressing low endogenous Wnt-11 inhibited β-catenin/Tcf activity and increased ATF2-dependent transcriptional activity. WNT11 gene silencing and antibody-mediated inhibition of Wnt-11 in colorectal cancer cell lines expressing high Wnt-11 reduced their capacity for invasion. Together, these observations suggest that Wnt-11 could be a potential target for the treatment of patients with invasive colorectal cancer.

Long noncoding RNA GAS5 inhibits angiogenesis and metastasis of colorectal cancer through the Wnt/β-catenin signaling pathway

OBJECTIVE

Angiogenesis plays a key role in the tumorigenesis and progression of colorectal cancer (CRC). In this study, we investigated the effect of long noncoding RNA (lncRNA) GAS5 on the angiogenesis, invasion, and metastasis of CRC, and the involvement of the Wnt/β-catenin signaling pathway.

METHODS

CRC tissues and adjacent normal tissues were collected from 52 patients with CRC. GAS5 expression was determined in vivo and in vitro by real-time quantitative polymerase chain reaction (RT-qPCR). Then RT-qPCR and Western blot were used to identify expression of key genes of Wnt/β-catenin signaling pathway. CRC cells with lowest GAS5 expression were selected and subjected to si-GAS5, oe-GAS5, or XAV939 to validate the effect of GAS5 and Wnt/β-catenin signaling pathway on CRC cell activities. The activation of Wnt/β-catenin signaling pathway was determined in response to GAS5. Subcutaneous tumor growth and microvascular density were observed in nude mice, in which in vivo metastasis was observed following tail vein injection of CRC cells.

RESULTS

Initially, poor expression of GAS5 was observed in CRC tissues and cells. Upregulated GAS5 repressed CRC cell invasion and migration in vitro, as well as subcutaneous tumor growth, angiogenesis, and liver metastases in vivo. Furthermore, the Wnt/β-catenin signaling pathway was determined to be activated in CRC tissues and cells, while its activation was inhibited by GAS5. The Wnt/β-catenin signaling pathway promoted the CRC cell invasion and migration in vitro, subcutaneous tumor growth, angiogenesis and, liver metastases in vivo.

CONCLUSION

Taken together, the results of the study conclude that lncRNA GAS5 inhibited the activation of the Wnt/β-catenin signaling pathway, thereby suppressing the angiogenesis, invasion, and metastasis of CRC.

Intraflagellar transport 20 promotes collective cancer cell invasion by regulating polarized organization of Golgi-associated microtubules

Collective invasion is an important strategy of cancers of epithelial origin, including colorectal cancer (CRC), to infiltrate efficiently into local tissues as collective cell groups. Within the groups, cells at the invasive front, called leader cells, are highly polarized and motile, thereby providing the migratory traction that guides the follower cells. However, its underlying mechanisms remain unclear. We have previously shown that signaling emanating from the receptor tyrosine kinase Ror2 can promote invasion of human osteosarcoma cells and that intraflagellar transport 20 (IFT20) mediates its signaling to regulate Golgi structure and transport. Herein, we investigated the role of Ror2 and IFT20 in collective invasion of CRC cells, where Ror2 expression is either silenced or nonsilenced. We show by cell biological analyses that IFT20 promotes collective invasion of CRC cells, irrespective of expression and function of Ror2. Intraflagellar transport 20 is required for organization of Golgi‐associated, stabilized microtubules, oriented toward the direction of invasion in leader cells. Our results also indicate that IFT20 promotes reorientation of the Golgi apparatus toward the front side of leader cells. Live cell imaging of the microtubule plus‐end binding protein EB1 revealed that IFT20 is required for continuous polarized microtubule growth in leader cells. These results indicate that IFT20 plays an important role in collective invasion of CRC cells by regulating organization of Golgi‐associated, stabilized microtubules and Golgi polarity in leader cells.

Protocadherin 17 is a tumor suppressor and is frequently methylated in nasopharyngeal carcinoma

Purpose

Several PCDH genes were shown to be downregulated or silenced in carcinomas and act as candidate tumor suppressor genes. However, the functions of PCDH17 in nasopharyngeal carcinoma (NPC) remain unclear. Here, we investigated the PCDH17 promoter methylation status and its impact on the expression and functions of PCDH17 in NPC.

Patients and methods

To determine the mRNA levels and promoter methylation status of PCDH17 in NPC cell lines as well as 42 NPC patient specimens, we performed reverse transcription PCR, methylation-specific PCR, and bisulfite genome sequencing. The effects of ectopic PCDH17 expression in NPC cell lines were determined by colony formation, cell proliferation, wound healing, in vitro human umbilical vein endothelial cells tube formation, migration, invasion, cell cycle, and apoptosis assays and an in vivo subcutaneous tumor model.

Results

PCDH17 expression was almost absent or significantly reduced in 100% of the NPC cell lines (5/5). However, 5-aza-2′-deoxycytidine and trichostatin A treatment restored PCDH17 expression. Promoter methylation was involved in PCDH17 silencing. Ectopic expression of PCDH17 in silenced NPC cells reduced colony formation, cell migration, angiogenesis, VEGF secretion, and tumorigenicity.

Conclusion

PCDH17 plays a tumor suppressor role in NPC. PCDH17 methylation may be a tumor-specific event and can be used as an epigenetic biomarker for NPC.

Therapeutic potential of targeting the Wnt/β-catenin signaling pathway in colorectal cancer

Aberrant Wnt/β-catenin signaling has often been reported in different cancers, particularly colorectal cancer (CRC), and this signaling cascade is central to carcinogenesis. Approximately 80% of CRC cases harbor mutations in the adenomatous polyposis coli gene, and half of the remaining cases feature mutations in the β-catenin gene that affect the Wnt/β-catenin signaling pathway. Unsurprisingly, the Wnt/β-catenin signaling pathway has potential value as a therapeutic target in the treatment of CRC. Several inhibitors of the Wnt/β-catenin signaling pathway have been developed for CRC treatment, but so far no molecular therapeutic targeting this pathway has been incorporated into oncological practice. In this review, we discuss the role of Wnt/β-catenin signaling in CRC and its potential as a target of innovative therapeutic approaches for CRC.

An update of Wnt signalling in endometrial cancer and its potential as a therapeutic target

Endometrial cancer is the most common gynaecological malignancy in developed nations, and its prevalence is rising as women defer or decide not to have children and as obesity rises, both key risk factors. Despite this, treatment options remain limited, particularly for advanced or refractory disease. New genomic analyses have revealed distinct mutational profiles with therapeutic and prognostic potential. Wnt signalling, which is pivotal in embryogenesis, healing and homeostasis, is of importance in the endometrium and has been linked to carcinogenesis. This review aims to update and discuss the current evidence for the role of β-catenin dependent and independent Wnt signalling, including the ROR receptors in the endometrium and its potential as a therapeutic target, in light of recent trials of Wnt-targeted therapy in multiple tumour types.

CpG Island Methylator Phenotype and Methylation of Wnt Pathway Genes Together Predict Survival in Patients with Colorectal Cancer

PURPOSE

Dysregulation of the Wnt pathway is a crucial step in the tumorigenesis of colorectal cancer (CRC). This study aimed to determine whether DNA methylation of Wnt pathway genes helps predict treatment response and survival in patients with metastatic or recurrent CRC.

MATERIALS AND METHODS

We retrospectively collected primary tumor tissues from 194 patients with metastatic or recurrent CRC. Pyrosequencing was used to examine the methylation of 10 CpG island loci in DNA extracted from formalin-fixed paraffin-embedded specimens. To elucidate the predictive role of DNA methylation markers, Kaplan-Meier survival estimation and Cox regression were performed for progression-free survival and overall survival (OS).

RESULTS

The methylation frequencies of the 10 genes analyzed (p16, p14, MINT1, MINT2, MINT31, hMLH1, DKK3, WNT5A, AXIN2, and TFAP2E) were 47.9%, 10.8%, 21.1%, 16.0%, 20.6%, 0.5%, 53.1%, 32.0%, 2.6%, and 2.1%, respectively. We divided patients into three groups based on the number of methylated genes (group 1, no methylation n=38; group 2, 1-2 methylations n=92; group 3, 3 or more methylations n=64). Among patients treated with palliative chemotherapy (n=167), median OSs of groups 1, 2, and 3 were 39.1, 39.7, and 29.1 months, respectively (log rank p=0.013). After adjustment, number of methylations was identified as an independent poor prognostic factor (0-2 methylated vs. ≥3 methylated: hazard ratio, 1.72; 95% confidence interval, 1.16-2.56, p=0.007).

CONCLUSION

This study suggests that methylation of Wnt pathway genes, in addition to known CpG island methylator phenotype markers, may help predict treatment outcome and survival in patients with CRC.

Emerging role and therapeutic implication of Wnt signaling pathways in liver fibrosis

Activation of hepatic stellate cells (HSCs) is a pivotal cellular event in liver fibrosis. Therefore, improving our understanding of the molecular pathways that are involved in these processes is essential to generate new therapies for liver fibrosis. Greater knowledge of the role of the Wnt signaling pathway in liver fibrosis could improve understanding of the liver fibrosis pathogenesis. The aim of this review is to describe the present knowledge about the Wnt signaling pathway, which significantly participates in liver fibrosis and HSC activation, and look ahead on new perspectives of Wnt signaling pathway research. Moreover, we will discuss the different interactions with Wnt signaling pathway-regulated liver fibrosis. The Wnt signaling pathway modulates several important aspects of function, including cell proliferation, activation and differentiation. Targeting the Wnt signaling pathway can be a promising direction in liver fibrosis treatment. We discuss new perspectives of Wnt signaling pathway activation in liver fibrosis. For example, antagonist to Wnt and Wnt ligands could inhibit liver fibrosis by regulating Wnt/β-catenin signaling pathway. These findings identify the Wnt signaling pathway as a potentially important for therapeutic targets in liver fibrosis. Future studies are needed in order to find safer and more effective Wnt-based drugs.

Association Analysis between Body Mass Index and Genomic DNA Methylation across 15 Major Cancer Types

Cancer incidence and mortality increase with increasing body mass index (BMI), but BMI-associated epigenetic alterations in cancer remain elusive. We hypothesized that BMI would be associated with DNA methylation alterations in cancers. To test this hypothesis, here, we estimated the associations between DNA methylation and BMI through two different methods across 15 cancer types, at approximately 485,000 CpG sites and 2415 samples using data from The Cancer Genome Atlas. After comparing the DNA methylation levels in control BMI and high BMI individuals, we found differentially methylated CpG sites (DMSs) in cholangiocarcinoma (CHOL), colon adenocarcinoma (COAD), and uterine corpus endometrial carcinoma (UCEC) (False Discovery Rate < 0.05). The DMSs of COAD or UCEC were enriched in several obesity-induced and cancer-related pathways. Next, when BMI was used as a continuous variable, we identified BMI-associated methylated CpG sites (BMS) (P (Bonferroni) < 0.05) in CHOL (BMS = 1), COAD (BMS = 1), and UCEC (BMS = 4) using multivariable linear regression. In UCEC, three of the BMSs can predict the clinical outcomes and survival of patients with the tumors. Overall, we observed associations between DNA methylation and high BMI in CHOL, COAD, and UCEC. Furthermore, three BMI-associated CpGs were identified as potential biomarkers for UCEC prognosis.

Role of WNT5A receptors FZD5 and RYK in prostate cancer cells

Prostate cancer is the most common malignancy in men and has a high propensity to metastasize to bone. WNT5A has recently been implicated in the progression of prostate cancer, however, the receptors that mediate its effects remain unknown. Here, we identified Wnt receptors that are highly expressed in prostate cancer and investigated which of these receptors mediate the anti-tumor effects of WNT5A in prostate cancer in vitro.

Extensive in vitro analyses revealed that the WNT5A receptors FZD5 and RYK mediate the anti-tumor effects of WNT5A on prostate cancer cells. Knock-down of FZD5 completely abrogated the anti-proliferative effect of WNT5A in PC3 cells. In contrast, knock-down of RYK and FZD8 did not rescue the inhibition of proliferation after WNT5A overexpression. In contrast, RYK knock-down inhibited the pro-apoptotic effect of WNT5A in PC3 cells by 60%, whereas the knock-down of either FZD5 or FZD8 further stimulated apoptosis after WNT5A overexpression (by 33% and 234%, respectively). Surface plasmon resonance analysis indicated that WNT5A has a 30% stronger binding response to FZD5 than to RYK. Further investigations using a tissue microarray revealed that expression of RYK is increased in advanced prostate cancer tumor stages, but is not associated with survival of prostate cancer patients. In contrast, patients with low local FZD5 expression, in particular in combination with low WNT5A expression, showed a longer disease-specific survival.

In conclusion, WNT5A/FZD5 and WNT5A/RYK signaling are both involved in mediating the pro-apoptotic and anti-proliferative effects of WNT5A in prostate cancer.

Multiproteomic and Transcriptomic Analysis of Oncogenic β-Catenin Molecular Networks

The dysregulation of Wnt signaling is a frequent occurrence in many different cancers. Oncogenic mutations of CTNNB1/β-catenin, the key nuclear effector of canonical Wnt signaling, lead to the accumulation and stabilization of β-catenin protein with diverse effects in cancer cells. Although the transcriptional response to Wnt/β-catenin signaling activation has been widely studied, an integrated understanding of the effects of oncogenic β-catenin on molecular networks is lacking. We used affinity-purification mass spectrometry (AP-MS), label-free liquid chromatography-tandem mass spectrometry, and RNA-Seq to compare protein-protein interactions, protein expression, and gene expression in colorectal cancer cells expressing mutant (oncogenic) or wild-type β-catenin. We generate an integrated molecular network and use it to identify novel protein modules that are associated with mutant or wild-type β-catenin. We identify a DNA methyltransferase I associated subnetwork that is enriched in cells with mutant β-catenin and a subnetwork enriched in wild-type cells associated with the CDKN2A tumor suppressor, linking these processes to the transformation of colorectal cancer cells through oncogenic β-catenin signaling. In summary, multiomics analysis of a defined colorectal cancer cell model provides a significantly more comprehensive identification of functional molecular networks associated with oncogenic β-catenin signaling.

Oncogenic BRAF mutation induces DNA methylation changes in a murine model for human serrated colorectal neoplasia

Colorectal cancer is a major cause of cancer death and approximately 20% arises within serrated polyps, which are under-recognized and poorly understood. Human serrated colorectal polyps frequently exhibit both oncogenic BRAF mutation and widespread DNA methylation changes, which are important in silencing genes restraining neoplastic progression. Here, we investigated whether in vivo induction of mutant Braf is sufficient to result in coordinated promoter methylation changes for multiple cancer-related genes. The Braf^V637E mutation was induced in murine intestine on an FVB;C57BL/6J background and assessed for morphological and DNA methylation changes at multiple time points from 10 days to 14 months. Extensive intestinal hyperplasia developed by 10 days post-induction of the mutation. By 8 months, most mice had murine serrated adenomas with dysplasia and invasive cancer developed in 40% of mice by 14 months. From 5 months onwards, Braf mutant mice showed extensive, gene-specific increases in DNA methylation even in hyperplastic mucosa without lesions. This demonstrates that persistent oncogenic Braf signaling is sufficient to induce widespread DNA methylation changes. This occurs over an extended period of time, mimicking the long latency followed by rapid progression of human serrated neoplasia. This study establishes for the first time that DNA methylation arises slowly in direct response to prolonged oncogenic Braf signaling in serrated polyps; this finding has implications both for chemoprevention and for understanding the origin of DNA hypermethylation in cancer generally.