Wnt Β-catenin Pathway Research Articles

MiR-199a-5p modulates choroidal neovascularization by regulating Wnt7b/Wnt/β-catenin signaling pathway.

Choroidal neovascularization (CNV) can be seen in many fundus diseases, and lead to fundus exudation, bleeding, or vision loss. miRNAs are vital regulator in CNV. miR-199a-5p has been proved to be involved in regulating vascular formation of endothelial cells, but its role in CNV remains unclear. This study aims to study the role of miR-199a-5p in CNV. Laser irradiation was used to induce CNV model. The lesion area of CNV was calculated by high-resolution angiography with fluorescein isothiocyanate-dextran. Wnt family member 7b (Wnt7b), β-catenin, and Wnt pathway proteins was measured by western blot. Immunofluorescence was performed to test Wnt7b, β-catenin, CD31, and p-p65. miR-199a-5p and Wnt7b mRNA were tested by reverse transcription real-time polymerase chain reaction. Cell count kit-8, wound healing, Transwell, tube formation, and flow cytometry were used to detect the function of miR-199a-5p and Wnt7b on human retinal microvascular endothelial cells (HRMEC). TargetScan database and dual-luciferase reporter assay verified the interaction between miR-199a-5p and Wnt7b. The results revealed that Wnt7b increased in CNV rats. Knocking down Wnt7b repressed cell proliferation, migration, invasion, and angiogenesis, and accelerated cell apoptosis of HRMEC. Dual-luciferase reporter assay verified that miR-199a-5p targeted Wnt7b. Overexpression of miR-199a-5p inhibited the angiogenesis of HRMEC and promoted cell apoptosis by inhibiting Wbt7b. In vivo experiment found that Wnt7b rescued the promotion of miR-199a-5p inhibition on CNV lesion of rats. In addition, Wnt7b positively regulated Wnt/β-catenin signaling pathway and promoted the angiogenesis of HRMEC. In conclusion, overexpression of miR-199a-5p inhibited the angiogenesis of HRMEC by regulating Wnt7b/Wnt/β-catenin signaling pathway, which may serve as a promising therapy target of CNV.

PRMT6-mediated transcriptional activation of ythdf2 promotes glioblastoma migration, invasion, and emt via the wnt–β-catenin pathway

BackgroundProtein arginine methyltransferase 6 (PRMT6) plays a crucial role in various pathophysiological processes and diseases. Glioblastoma (GBM; WHO Grade 4 glioma) is the most common and lethal primary brain tumor in adults, with a prognosis that is extremely poor, despite being less common than other systemic malignancies. Our current research finds PRMT6 upregulated in GBM, enhancing tumor malignancy. Yet, the specifics of PRMT6’s regulatory processes and potential molecular mechanisms in GBM remain largely unexplored.MethodsPRMT6’s expression and prognostic significance in GBM were assessed using glioma public databases, immunohistochemistry (IHC), and immunoblotting. Scratch and Transwell assays examined GBM cell migration and invasion. Immunoblotting evaluated the expression of epithelial-mesenchymal transition (EMT) and Wnt-β-catenin pathway-related proteins. Dual-luciferase reporter assays and ChIP-qPCR assessed the regulatory relationship between PRMT6 and YTHDF2. An in situ tumor model in nude mice evaluated in vivo conditions.ResultsBioinformatics analysis indicates high expression of PRMT6 and YTHDF2 in GBM, correlating with poor prognosis. Functional experiments show PRMT6 and YTHDF2 promote GBM migration, invasion, and EMT. Mechanistic experiments reveal PRMT6 and CDK9 co-regulate YTHDF2 expression. YTHDF2 binds and promotes the degradation of negative regulators APC and GSK3β mRNA of the Wnt-β-catenin pathway, activating it and consequently enhancing GBM malignancy.ConclusionsOur results demonstrate the PRMT6-YTHDF2-Wnt-β-Catenin axis promotes GBM migration, invasion, and EMT in vitro and in vivo, potentially serving as a therapeutic target for GBM.

Abstract 4369: CYP3A5 promotes aggressive and therapeutically resistant prostate cancer by modulating AR and Wnt signaling: Implications for racially disparate clinical outcomes

Abstract Prostate cancer (PC) is the second leading cause of cancer-related death in American men, which disproportionately affects Black/African American (AA) men. The androgen receptor (AR) signaling plays a pivotal role in PC development and is a primary target for intervention in patients with advanced disease. Aberrant activation of AR is also suggested to play a significant role in castration-resistant prostate cancer (CRPC). Despite advancements in anti-androgen therapies with new targeting agents, such as enzalutamide, metastatic CRPC (mCRPC) remains incurable. CYP3A5, a monooxygenase expressed in the prostate, liver and intestine, is involved in drug metabolism and steroid biosynthesis. We earlier reported that intratumoral CYP3A5 activated AR signaling by facilitating its nuclear translocation of AR. More notably, we found a higher CYP3A5 expression in AAs, attributed to the *1 CYP3A5 variant, as compared to non-Hispanic White Americans (NHWA) possessing the *3 variant. Analysis of RNA-seq data using patient tumor samples revealed that elevated CYP3A5 in AA PC patients was associated with Wnt-β catenin signaling activation via TCF4 overexpression. Here, we investigated the role of CYP3A5 in enzalutamide resistance and Wnt signaling by generating enzalutamide-resistant PC cell lines of NHWA (low CYP3A5-LNCaP) and AA-origin (high CYP3A5-MDAPCa2b). RT-qPCR assay was used to examine the changes in AR and CYP3A5 expression between the parental and the enzalutamide-resistant cell lines. The data show heightened CYP3A5 expression in enzalutamide-resistant cells of AA origin (MDAPCa2b/EnzR) but not of NHWA origin (LNCaP/EnzR). Interestingly, MDAPCa2b/EnzR exhibited no change in AR levels whereas it was increased in LNCaP/EnzR cells relative to parental lines. A loss of function assay was performed for siRNA-mediated silencing of CYP3A5 to study its effect on Wnt signaling. RNA sequencing results show that CYP3A5 inhibition in MDAPCa2b downregulated Wnt pathway genes (Wnt5A, Wnt10B, Wnt11, Fzd2, and Dvl3). These observations align with our previous RNA seq results using patient samples where we observed upregulated Wnt-β catenin signaling in high CYP3A5 expressing patient tumor samples. Western analysis post-CYP3A5 inhibition in LNCaP and MDAPCa2b cells revealed upregulated Axin and downregulated LRP6 and Dvl-3, signifying CYP3A5's regulation of the canonical Wnt-β catenin pathway. Additionally, MDAPCa2b saw downregulated Wnt 5A and Wnt 10B, known to influence the Wnt non-canonical pathway. Altogether, our data suggest that *1 CYP3A5 variant in AAs likely contributes to aggressive behavior and therapeutic resistance of PC and serves as a molecular determinant of disparate clinical outcomes. Citation Format: Jake McLean, Ajay P. Singh, Edwin Oh, Ranjana Mitra. CYP3A5 promotes aggressive and therapeutically resistant prostate cancer by modulating AR and Wnt signaling: Implications for racially disparate clinical outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4369.

Retraction: MicroRNA-940 Targets INPP4A or GSK3β and Activates the Wntβ-Catenin Pathway to Regulate the Malignant Behavior of Bladder Cancer Cells.

[This retracts the article DOI: 10.3727/096504017X14902261600566.].

Spatial immunophenotypes predict clinical outcome in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a severe malignant tumour that shows only modest responses to immunotherapy. We aimed to identify the spatial immunophenotypes of iCCA and delineate potential immune escape mechanisms. Multiplex immunohistochemistry (mIHC) was performed to quantitatively evaluate the distribution of 16 immune cell subsets in intratumour, invasive margin and peritumour areas in a cohort of 192 treatment-naïve patients with iCCA. Multiregion unsupervised clustering was used to determine three spatial immunophenotypes, and multiomics analyses were carried out to explore functional differences.Results: iCCA displayed a region-specific distribution of immune cell subsets with abundant CD15+ neutrophil infiltration in intratumour areas. Three spatial immunophenotypes encompassing inflamed (35%), excluded (35%) and ignored (30%) phenotypes were identified. The inflamed phenotype showed characteristics of abundant immune cell infiltration in intratumour areas, increased PD-L1 expression and relatively favourable overall survival. The excluded phenotype with a moderate prognosis was characterized by immune cell infiltration restricted to the invasive margin or peritumour areas and upregulation of activated hepatic stellate cells, extracellular matrix and Notch signalling pathways. The ignored phenotype, with scarce immune cell infiltration across all subregions, was associated with MAPK signalling pathway elevation and a poor prognosis. The excluded and ignored phenotypes, constituting non-inflamed phenotypes, shared features of an increased angiogenesis score, TGF-β and Wnt-β catenin pathway upregulation and were enriched for BAP1 mutations and FGFR2 fusions. We identified three spatial immunophenotypes with different overall prognoses in iCCA. Tailored therapies based on the distinct immune evasion mechanisms of the spatial immunophenotypes are needed. The contribution of immune cell infiltration in the invasive margin and peritumour areas has been proved. We explored the multiregional immune contexture of 192 patients to identify three spatial immunophenotypes in intrahepatic cholangiocarcinoma (iCCA). By integrating genomic and transcriptomic data, phenotype-specific biological behaviours and potential immune escape mechanisms were analysed. Our findings provide a rationale to develop personalized therapies for iCCA.

Short peptide domains of the Wnt inhibitor sFRP4 target ovarian cancer stem cells by neutralizing the Wnt β-catenin pathway, disrupting the interaction between β-catenin and CD24 and suppressing autophagy

AimsOne of the hallmarks of cancer stem cells (CSC) is hyperactive Wnt β-catenin signaling due to the decreased presence of Wnt antagonists such as secreted frizzled related protein 4 (SFRP4). Cysteine-rich domain (CRD) and netrin-like domain (NLD) are the two functional domains of SFRP4 having anti-tumor properties. In this study, we have explored the effectiveness of short micropeptides SC-301 (from CRD) and SC-401 (from NLD) on CSC properties, EMT, apoptosis and autophagy in ovarian CSCs enriched from PA-1 and SKOV-3 cell lines. Main methodsGene expression analysis, Western blot and immunocytochemistry were performed on ovarian CSCs to evaluate the inhibitory potential of micropeptides to various CSC associated oncogenic properties. Co-immunoprecipitation was performed to detect the binding of CD24 to β-catenin protein complex. CYTO-ID Autophagy Detection Kit 2.0 was used to monitor autophagic flux in peptide treated CSCs. Key findingsIt is clearly seen that the micropeptides derived from both the domains inhibit Wnt pathway, initiate apoptosis, inhibit migration and chemosensitize CSCs. Specifically, CD24, a defining marker of ovarian CSC was suppressed by peptide treatment. Notably, interaction between CD24 and β-catenin was disrupted upon peptide treatment. SFRP4 peptide treatment also suppressed the autophagic process which is crucial for CSC survival. SignificanceThe study demonstrated that although both peptides have inhibitory effects, SC-401 was emphatically more effective in targeting CSC properties and down regulating the Wnt β-catenin machinery.

Identifying novel interactions of the colon-cancer related APC protein with Wnt-pathway nuclear transcription factors

BackgroundColon cancer is often driven by mutations of the adenomatous polyposis coli (APC) gene, an essential tumor suppressor gene of the Wnt β-catenin signaling pathway. APC and its cytoplasmic interactions have been well studied. However, various groups have also observed its presence in the nucleus. Identifying novel interactions of APC in the Wnt pathway will provide an opportunity to understand APC’s nuclear role better and ultimately identify potential cancer treatment targets.MethodsWe used the all-vs-all sequencing (AVA-Seq) method to interrogate the interactome of protein fragments spanning most of the 60 Wnt β-catenin pathway proteins. Using protein fragments identified the interacting regions between the proteins with more resolution than a full-length protein approach. Pull-down assays were used to validate a subset of these interactions.Results74 known and 703 novel Wnt β-catenin pathway protein-protein interactions were recovered in this study. There were 8 known and 31 novel APC protein-protein interactions. Novel interactions of APC and nuclear transcription factors TCF7, JUN, FOSL1, and SOX17 were particularly interesting and confirmed in validation assays.ConclusionBased on our findings of novel interactions between APC and transcription factors and previous evidence of APC localizing to the nucleus, we suggest APC may compete and repress CTNNB1. This would occur through APC binding to the transcription factors (JUN, FOSL1, TCF7) to regulate the Wnt signaling pathway including through enhanced marking of CTNNB1 for degradation in the nucleus by APC binding with SOX17. Additional novel Wnt β-catenin pathway protein-protein interactions from this study could lead researchers to novel drug designs for cancer.

Yap and Taz promote osteogenesis and prevent chondrogenesis in neural crest cells in vitro and in vivo.

Neural crest cells (NCCs) are multipotent stem cells that can differentiate into multiple cell types, including the osteoblasts and chondrocytes, and constitute most of the craniofacial skeleton. Here, we show through in vitro and in vivo studies that the transcriptional regulators Yap and Taz have redundant functions as key determinants of the specification and differentiation of NCCs into osteoblasts or chondrocytes. Primary and cultured NCCs deficient in Yap and Taz switched from osteogenesis to chondrogenesis, and NCC-specific deficiency for Yap and Taz resulted in bone loss and ectopic cartilage in mice. Yap bound to the regulatory elements of key genes that govern osteogenesis and chondrogenesis in NCCs and directly regulated the expression of these genes, some of which also contained binding sites for the TCF/LEF transcription factors that interact with the Wnt effector β-catenin. During differentiation of NCCs in vitro and NCC-derived osteogenesis in vivo, Yap and Taz promoted the expression of osteogenic genes such as Runx2 and Sp7 but repressed the expression of chondrogenic genes such as Sox9 and Col2a1. Furthermore, Yap and Taz interacted with β-catenin in NCCs to coordinately promote osteoblast differentiation and repress chondrogenesis. Together, our data indicate that Yap and Taz promote osteogenesis in NCCs and prevent chondrogenesis, partly through interactions with the Wnt-β-catenin pathway.

Sex differences in adrenal cortex beta-catenin immunolocalisation of the Saharan gerbil, Libyan jird (Meriones libycus, Lichtenstein, 1823).

The adrenal cortex provides adequate steroidogenic responses to environmental changes. However, in desert rodents, the adrenocortical activity varies according to several factors especially sex, age, and seasonal variations. Herein, we examined the sex differences in the adrenal cortex activity and explored the involvement of sex hormones in the regulation of this function in Libyan jird Meriones libycus. Twenty-four adult male and female animals weighing 109-110 g were captured in the breeding season and equally assigned into control and gonadectomised groups. Animal euthanasia was performed 50 days after the gonadectomy. Adrenal gland was processed for structural and immunohistochemistry study of b-catenin, whereas plasma was used for cortisol assay. The results showed that female adrenal gland weight was heavier than male and gonadectomy reduced this dimorphism. The adrenal cortex thickness was greater in the female than in the male, mainly due to significant development of the zona fasciculata. Females presented higher cell density in fasciculata and reticularis zones. The plasma cortisol was higher in females than in males. The immunolocalisation of beta-catenin showed that the expression was particularly glomerular in both sexes. However, in the female, the immunostaining was present in the zona reticularis while it was absent in the control male. Orchiectomy reduced zona glomerulosa cell density and induced hypertrophy of zona reticularis characterised by strong beta-catenin immunoreactivity. Results indicated that sex hormones had a major role in the regulation of the Saharan gerbil's adrenal homeostasis by modulating beta-catenin signalling. Androgens seem to inhibit the Wnt-beta-catenin pathway and oestrogens are activators of the adrenal inner zones.

PI(4,5)P2-stimulated positive feedback drives the recruitment of Dishevelled to Frizzled in Wnt-β-catenin signaling.

In the Wnt-β-catenin pathway, Wnt binding to Frizzled (Fzd) and LRP5 or LRP6 (LRP5/6) co-receptors inhibits the degradation of the transcriptional coactivator β-catenin by recruiting the cytosolic effector Dishevelled (Dvl). Polymerization of Dvl at the plasma membrane recruits the β-catenin destruction complex, enabling the phosphorylation of LRP5/6, a key step in inhibiting β-catenin degradation. Using purified Fzd proteins reconstituted in lipid nanodiscs, we investigated the factors that promote the recruitment of Dvl to the plasma membrane. We found that the affinity of Fzd for Dvl was not affected by Wnt ligands, in contrast to other members of the GPCR superfamily for which the binding of extracellular ligands affects the affinity for downstream transducers. Instead, Fzd-Dvl binding was enhanced by increased concentration of the lipid PI(4,5)P2, which is generated by Dvl-associated lipid kinases in response to Wnt and which is required for LRP5/6 phosphorylation. Moreover, binding to Fzd did not promote Dvl DEP domain dimerization, which has been proposed to be required for signaling downstream of Fzd. Our findings suggest a positive feedback loop in which Wnt-stimulated local PI(4,5)P2 production enhances Dvl recruitment and further PI(4,5)P2 production to support Dvl polymerization, LRP5/6 phosphorylation, and β-catenin stabilization.

Bi-allelic variants in WNT7B disrupt the development of multiple organs in humans

BackgroundPulmonary hypoplasia, Diaphragmatic anomalies, Anophthalmia/microphthalmia and Cardiac defects delineate the PDAC syndrome. We aim to identify the cause of PDAC syndrome in patients who do not carry pathogenic variants in...

Current and Near-Future Treatment of Alzheimer's Disease.

Recent findings have improved our understanding of the multifactorial nature of AD. While in early asymptomatic stages of AD, increased amyloid-β synthesis and tau hyperphosphorylation play a key role, while in the latter stages of the disease, numerous dysfunctions of homeostatic mechanisms in neurons, glial cells, and cerebrovascular endothelium determine the rate of progression of clinical symptoms. The main driving forces of advanced neurodegeneration include increased inflammatory reactions in neurons and glial cells, oxidative stress, deficiencies in neurotrophic growth and regenerative capacity of neurons, brain insulin resistance with disturbed metabolism in neurons, or reduction of the activity of the Wnt-β catenin pathway, which should integrate the homeostatic mechanisms of brain tissue. In order to more effectively inhibit the progress of neurodegeneration, combination therapies consisting of drugs that rectify several above-mentioned dysfunctions should be used. It should be noted that many widely-used drugs from various pharmacological groups, "in addition" to the main therapeutic indications, have a beneficial effect on neurodegeneration and may be introduced into clinical practice in combination therapy of AD. There is hope that complex treatment will effectively inhibit the progression of AD and turn it into a slowly progressing chronic disease. Moreover, as the mechanisms of bidirectional communication between the brain and microbiota are better understood, it is expected that these pathways will be harnessed to provide novel methods to enhance health and treat AD.

Unravelling the Structural Mechanism of Action of 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl)phenyl]imidazolidine-2,4-dione in Dual-Targeting Tankyrase 1 and 2: A Novel Avenue in Cancer Therapy.

Tankyrase (TNKS) belonging to the poly(ADPribose) polymerase family, are known for their multi-functioning capabilities, and play an essential role in the Wnt β-catenin pathway and various other cellular processes. Although showing inhibitory potential at a nanomolar level, the structural dual-inhibitory mechanism of the novel TNKS inhibitor, 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl)phenyl]imidazolidine-2,4-dione, remains unexplored. By employing advanced molecular modeling, this study provides these insights. Results of sequence alignments of binding site residues identified conserved residues; GLY1185 and ILE1224 in TNKS-1 and PHE1035 and PRO1034 in TNKS-2 as crucial mediators of the dual binding mechanism of 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl)phenyl]imidazolidine-2,4-dione, corroborated by high per-residue energy contributions and consistent high-affinity interactions of these residues. Estimation of the binding free energy of 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl)phenyl]imidazolidine-2,4-dione showed estimated total energy of -43.88 kcal/mol and -30.79 kcal/mol towards TNKS-1 and 2, respectively, indicating favorable analogous dual binding as previously reported. Assessment of the conformational dynamics of TNKS-1 and 2 upon the binding of 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl)phenyl]imidazolidine-2,4-dione revealed similar structural changes characterized by increased flexibility and solvent assessible surface area of the residues inferring an analogous structural binding mechanism. Insights from this study show that peculiar, conserved residues are the driving force behind the dual inhibitory mechanism of 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl)phenyl]imidazolidine-2,4-dione and could aid in the design of novel dual inhibitors of TNKS-1 and 2 with improved therapeutic properties.

Inflamed and non-inflamed classes of HCC: a revised immunogenomic classification

ObjectiveWe previously reported a characterisation of the hepatocellular carcinoma (HCC) immune contexture and described an immune-specific class. We now aim to further delineate the immunogenomic classification of HCC to incorporate...

Genotypes and Haplotypes in the AXIN2 and TCF7L2 Genes are Associated With Susceptibility and With Clinicopathological Characteristics in Breast Cancer Patients.

Background: Breast cancer is a multifactorial disease whose genetic susceptibility is related to polymorphic variants of cell proliferation and migration pathways. Variants in AXIN2 and TCF7L2 in the Wnt-β catenin pathway have been associated with different types of cancer; however, little is known about its role in breast cancer. This study tests the hypothesis of links between AXIN2 rs1133683 and rs2240308, and TCF7L2 rs7903146 and rs12255372 variants in breast cancer. Methods: Peripheral blood samples were obtained from 404 women (202 patients and 202 control females). The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methodology was used to identify the gene variants. Results: The AXIN2 rs2240308 (C > T), and TCF7L2 rs7903146 (C > T) and rs12255372 (G > T) variants were associated with breast cancer and with age, TNM stage, and histologic-molecular subtype (p = 0.001). Likewise, the haplotype T-T in the TCF7L2 gene (rs7903146-rs12253372) was significantly related with breast cancer (OR = 2.66, 95%, CI = 1.64–4.30, p = 0.001). Conclusion: Our data show a link between AXIN2 rs2240308 and TCF7L2 rs7903146 and rs12255372 variants in breast cancer, and speculate this may be important in pathogenesis.

Rs708113 in WNT3A-WNT9A and hepatocellular carcinoma risk.

Hepatocellular carcinoma is the most frequent primary liver malignancy and fourth most common cause of cancer-related mortality worldwide. 1 Global Burden of Disease Cancer CollaborationGlobal, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-adjusted life-years for 32 cancer groups, 1990 to 2015: a systematic analysis for the global burden of disease study. JAMA Oncol. 2017; 3: 524-548 Crossref PubMed Scopus (2549) Google Scholar Although chronic viral hepatitis, particularly due to hepatitis B virus (HBV) infection, is the most common underlying liver disease leading to hepatocellular carcinoma in southeast Asia, alcohol-related liver disease and non-alcoholic fatty liver disease are the predominant causes in Europe and North America. Alcohol-related liver disease and non-alcoholic fatty liver disease are expected to become the leading causes of hepatocellular carcinoma in the future, with HBV and hepatitis C virus infections declining as a result of effective vaccination strategies and treatments. With few exceptions, most hepatocellular carcinoma cases in high-income countries develop in patients with established cirrhosis; alcohol-related cirrhosis is the second most common risk factor for hepatocellular carcinoma in high-income countries, 2 West J Card TR Aithal GP Fleming KM Risk of hepatocellular carcinoma among individuals with different aetiologies of cirrhosis: a population-based cohort study. Aliment Pharmacol Ther. 2017; 45: 983-990 Crossref PubMed Scopus (40) Google Scholar with an annual risk of hepatocellular carcinoma of up to 2·5%. 3 Mancebo A González-Diéguez ML Cadahía V et al. Annual incidence of hepatocellular carcinoma among patients with alcoholic cirrhosis and identification of risk groups. Clin Gastroenterol Hepatol. 2013; 11: 95-101 Summary Full Text Full Text PDF PubMed Scopus (108) Google Scholar Alcohol-related hepatocellular carcinoma is a complex disease, but easily discernible clinical risk factors include type 2 diabetes, obesity, and older age. 4 Llovet JM Kelley RK Villanueva A et al. Hepatocellular carcinoma. Nat Rev Dis Primers. 2021; 7: 6 Crossref PubMed Scopus (708) Google Scholar Sequence variations in specific genes that modify the risk of alcohol-related hepatocellular carcinoma have been identified, mostly by means of candidate gene case-control studies, which either enhance or alleviate the risk of developing hepatocellular carcinoma. However, the genetic risk loci recognised until now only represent a fraction of the heritability risk, suggesting that additional genetic modulators might exist. 5 Stickel F Buch S Nischalke HD et al. Genetic variants in PNPLA3 and TM6SF2 predispose to the development of hepatocellular carcinoma in individuals with alcohol-related cirrhosis. Am J Gastroenterol. 2018; 113: 1475-1483 Crossref PubMed Scopus (56) Google Scholar The involvement of the rs738409 locus (in the gene coding for PNPLA3) is widely supported by numerous case-control studies, which show the largest effect size among all previously identified genetic risk variants. Additional loci in genes coding for TM6SF2 (rs58542926) and HSD17B13 (rs72613567:TA) were found to increase and alleviate the risk of hepatocellular carcinoma, respectively. 5 Stickel F Buch S Nischalke HD et al. Genetic variants in PNPLA3 and TM6SF2 predispose to the development of hepatocellular carcinoma in individuals with alcohol-related cirrhosis. Am J Gastroenterol. 2018; 113: 1475-1483 Crossref PubMed Scopus (56) Google Scholar , 6 Stickel F Lutz P Buch S et al. Genetic variation in HSD17B13 reduces the risk of developing cirrhosis and hepatocellular carcinoma in alcohol misusers. Hepatology. 2020; 72: 88-102 Crossref PubMed Scopus (52) Google Scholar However, unlike in viral hepatitis-associated hepatocellular carcinoma, 7 Jiang DK Sun J Cao G et al. Genetic variants in STAT4 and HLA-DQ genes confer risk of hepatitis B virus-related hepatocellular carcinoma. Nat Genet. 2013; 45: 72-75 Crossref PubMed Scopus (242) Google Scholar , 8 Kumar V Kato N Urabe Y et al. Genome-wide association study identifies a susceptibility locus for HCV-induced hepatocellular carcinoma. Nat Genet. 2011; 43: 455-458 Crossref PubMed Scopus (303) Google Scholar a comprehensive and hypothesis-free genome-wide study to detect risk loci that might have remained unidentified for alcohol-related hepatocellular carcinoma so far has been lacking. Common genetic variation in alcohol-related hepatocellular carcinoma: a case-control genome-wide association studyWNT3A-WNT9A is a susceptibility locus for alcohol-related hepatocellular carcinoma, suggesting an early role of the Wnt–β-catenin pathway in alcohol-related hepatocellular carcinoma carcinogenesis. Full-Text PDF

EHMT2 promotes the pathogenesis of hepatocellular carcinoma by epigenetically silencing APC expression

BackgroundHepatocellular carcinoma (HCC), the second leading cause of cancer death worldwide, alone accounts for over half (466,100) of new cancer cases and 422,100 deaths based on the average year incidence rates of 2009 to 2011 in China. Due to unclear and complex underlying mechanisms for HCC development, effective therapy for HCC is still unavailable. The Wnt–β-catenin pathway is a critical contributor of HCC pathogenesis: 40–70% of HCCs from patients harbor the nuclear accumulation of β-catenin protein. However, the mechanisms for β-catenin activation are not fully understood.MethodsThe deletion of EHMT2 in Hep3B and Huh1 cells was achieved by transiently transfecting cells with pX459 plasmids, which carry EHMT2 specific small guide RNA (sgRNA) sequences for Cas9 protein. All experiments were performed in triplicate and repeated more than three times.ResultsIn the present study, we observed that EHMT2 (but not EHMT1) mRNA and protein levels were significantly elevated in HCC compared with normal controls. Next, the results of Ki67 staining, as well as MTT, soft-agar and xenograft assays, in wild-type and EHMT2−/− Hep3B and Huh1 cancer stem cells collectively revealed that the elevation of EHMT2 expression is required for the tumorigenesis of HCC. Meanwhile, we found that elevated EHMT2 expression contributes to the activation of Wnt–β-catenin signaling: deletion of EHMT2 in Hep3B or Huh1 cells promoted the cytoplasmic localization of β-catenin and restrained the expression of Wnt–β-catenin signaling targets such as Myc, CCND1, MMP-7, etc. We demonstrated that EMHT2 directly mediates the H3K9me2 methylation of the APC promoter to epigenetically silence its expression. More intriguingly, our findings also showed that UNC0642, a specific inhibitor of EHMT2, exhibits anti-tumorigenesis effects in HCC both in vitro and in vivo, which were largely abolished by deletion of EHMT2 or overexpression of APC in Hep3B and Huh1 cells.ConclusionAltogether, our observations emphasize that the EHMT2–APC axis is a critical contributor to Wnt–β-catenin pathway activation in HCC, and UNC0642 may be a potential candidate for target drug treatment of HCC.

Concurrent Down-regulation of the EAF1 and the EAF2 Genes in the Invasive Ductal Carcinoma Type of Breast Cancer

In mammals, the EAF1 and EAF2 genes build an active transcription module with other components. These genes code for factors acting as potent inhibitor of the Wnt-β catenin pathway, which might be due to their function as tumor suppressor gene. Recently, the involvement of both above-mentioned factors was described in some human tumors, but not yet in breast cancer. Breast cancer is one of the most cancer cases in Iran after colon and stomach carcinoma. We aimed therefore to investigate for the first time a possible correlation between breast cancer and the EAF1 and the EAF2 gene expression. We collected invasive ductal carcinoma tumor grading (grade 1 to 3) with marginal normal tissue from forty women diagnosed with breast cancer with the average age of 50 years old. All patients underwent triple marker test (ER/PR and Her2/neu), indeed the most of them were triple positive with few triple negative individuals. After RNA extraction, cDNA was synthesized for subsequent real-time polymerase chain reaction. The humanRPL27 gene wasusedas endogenous control. Analysis of real-time PCR results showeda significant down-regulation of EAF1 (p-value: 0.028), and of EAF2 (p-value: 0.0134) in tumor tissue samples in comparison to normal one.There was no correlation between clinical parameters and the target genes. We could find significant connection between both tumor suppressor genes in triple positive and triple negative breast cancer patients, which deserves more attention.

Assessment of anti-cancer effects of koenimbine on colon cancer cells.

Recent studies have highlighted the role of natural elements in reduction of cancer cell growth and apoptosis. Koenimbine, a natural product isolated from Murraya koenigii (L) Spreng is a substance with cytotoxic effects on cancer cells. The effects of koenimbine on HT-29 and SW48 colon cancer cells were evaluated by MTT and Annexin V assays. Expression levels of Wnt/β-catenin pathway genes were quantified by real time PCR. The IC50 values of koenimbine in HT-29 and SW48 was calculated to be 50μg/ml based on the results of MTT assay. This value was 75μg/ml in IEC-18 cells which were used as normal control. Annexin V assays revealed induction of cell apoptosis and necrosis in HT-29 and SW48 cells but not IEG18 cells by koenimbine. Koenimbin treatment resulted in significant down-regulation of CYCLD1 expression in SW48 cell line, but up-regulation of this gene in HT29 cell line. Expression of TBLR1, DKK1, GSK3B and β-catenin was significantly decreased after koenimbin treatment in HT-19 cell line. Moreover, expression of DKK1 and GSK3B was significantly decreased after koenimbin treatment in SW-40 cell line. TCF4 expression was not detected in any of cell lines either before or after treatment with koenimbin. The current in vitro study showed the cytotoxic effects of koenimbin on two colon cancer cell lines and the effects of this substance on expression of selected genes from Wnt-β catenin pathway. Future in vivo studies are needed before suggestion of this substance as an anti-cancer drug.

Lupeol Inhibits Growth and Migration in Two Human Colorectal Cancer Cell Lines by Suppression of Wnt-β-Catenin Pathway [Retraction

[This retracts the article DOI: 10.2147/OTT.S183925.].