Nuclear Accumulation Of Β-catenin Research Articles

Phosphorylation of LZTS2 by PLK1 activates the Wnt pathway

Lung adenocarcinoma (LUAD), responsible for nearly half of lung cancer cases, is one of the most prevalent and lethal malignant tumors globally. There is increasing evidence suggesting that the oncoprotein PLK1 plays a role in the onset and advancement of different types of cancer, including LUAD. Nonetheless, the precise mechanism by which PLK1 promotes tumorigenesis remains unclear. In this study, we demonstrate the upregulation of PLK1 in LUAD samples, which leads to a poor prognosis for LUAD patients. Intriguingly, PLK1 enables to bind to LZTS2 and promote its phosphorylation without affecting LZTS2 degradation. Furthermore, we identify that Ser451 is a key phosphorylation site in LZTS2 protein. LZTS2 exerts an anti-tumor effect by restricting the translocation of the transcription factor β-Catenin into the nucleus, thereby suppressing the Wnt pathway. PLK1 disrupts the interaction between LZTS2 and β-Catenin, resulting in the nuclear accumulation of β-Catenin and the activation of the Wnt pathway. Additionally, we reveal that LZTS2 inhibits the proliferation and migration of LUAD cells, which is rescued by PLK1. Finally, PLK1 inhibitors exhibit a dose-dependent suppression of LUAD cell proliferation and migration. Collectively, this study uncovers the pro-tumorigenic mechanism of PLK1, positioning it as a promising therapeutic target for Wnt-related LUAD.

The novel DNA methylation marker FIBIN suppresses non-small cell lung cancer metastasis by negatively regulating ANXA2

ObjectivesThe clinical T1 stage solid lung cancer with metastasis is a serious threat to human life and health. In this study, we performed RNA sequencing on T1 advanced-stage lung cancer and adjacent tissues to identify a novel biomarker and explore its roles in lung cancer. MethodsQuantitative reversed-transcription PCR, reverse transcription PCR and Western blot, MSP and Methtarget were utilized to evaluate FIBIN expression levels at both the transcriptional and protein levels as well as its methylation status. Differential target protein was evaluated for relative and absolute quantitation by isobaric tags. Co-IP was performed to detect the interactions between target protein. Precise location and expression levels of target proteins were revealed by immunofluorescence staining and component protein extraction using specific kits, respectively. ResultsWe reported that FIBIN was frequently silenced due to promoter hypermethylation in lung cancer. Additionally, both in vitro and in vivo experiments confirmed the significant anti-proliferation and anti-metastasis capabilities of FIBIN. Mechanistically, FIBIN decreased the nuclear accumulation of β-catenin by reducing the binding activity of GSK3β with ANXA2 while promoting interaction between GSK3β and β-catenin. ConclusionOur findings firstly identify FIBIN is a tumor suppressor, frequently silenced due to promoter hypermethylation. FIBIN may serve as a predictive biomarker for progression or metastasis among early-stage lung cancer patients.

PICK1 inhibits the malignancy of nasopharyngeal carcinoma and serves as a novel prognostic marker

Although many important advances have been made in the treatment of nasopharyngeal carcinoma (NPC) in recent years, local recurrence and distant metastasis remain the main factors affecting NPC prognosis. Biomarkers for predicting the prognosis of NPC need to be urgently identified. Here, we used whole-exon sequencing (WES) to determine whether PICK1 mutations are associated with the prognosis of NPC. Functionally, PICK1 inhibits the proliferation and metastasis of NPC cells both in vivo and in vitro. Mechanistically, PICK1 inhibited the expression of proteins related to the Wnt/β-catenin signaling pathway. PICK1 restrained the nuclear accumulation of β-catenin and accelerated the degradation of β-catenin through the ubiquitin-proteasome pathway. The reduced PICK1 levels were significantly associated with poor patient prognosis. Hence, our study findings reveal the mechanism by which PICK1 inactivates the Wnt/β-catenin signaling pathway, thereby inhibiting the progression of NPC. They support PICK1 as a potential tumor suppressor and prognostic marker for NPC.

Exosome-Mediated Paracrine Signaling Unveils miR-1246 as a Driver of Aggressiveness in Fusion-Negative Rhabdomyosarcoma.

Rhabdomyosarcoma is a pediatric cancer associated with aggressiveness and a tendency to develop metastases. Fusion-negative rhabdomyosarcoma (FN-RMS) is the most commonly occurring subtype of RMS, where metastatic disease can hinder treatment success and decrease survival rates. RMS-derived exosomes were previously demonstrated to be enriched with miRNAs, including miR-1246, possibly contributing to disease aggressiveness. We aimed to decipher the functional impact of exosomal miR-1246 on recipient cells and its role in promoting aggressiveness. Treatment of normal fibroblasts with FN-RMS-derived exosomes resulted in a significant uptake of miR-1246 paired with an increase in cell proliferation, migration, and invasion. In turn, delivery of miR-1246-mimic lipoplexes promoted fibroblast proliferation, migration, and invasion in a similar manner. Conversely, when silencing miR-1246 in FN-RMS cells, the resulting derived exosomes demonstrated reversed effects on recipient cells' phenotype. Delivery of exosomal miR-1246 targets GSK3β and promotes β-catenin nuclear accumulation, suggesting a deregulation of the Wnt pathway, known to be important in tumor progression. Finally, a pilot clinical study highlighted, for the first time, the presence of high exosomal miR-1246 levels in RMS patients' sera. Altogether, our results demonstrate that exosomal miR-1246 has the potential to alter the tumor microenvironment of FN-RMS cells, suggesting its potential role in promoting oncogenesis.

Effect of Piezo1 Channel-Mediated Mechanotransduction on Osteogenic Differentiation and Interleukin-6 Secretion in Bone Mesenchymal Stem Cells Under Tensile Strain

Physical stimulation plays a crucial role in the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (MSCs). However, the mechanotransductive mechanisms remain uncleared. Recent studies have suggested that the Piezo1 channel is essential for transforming mechanical signals. Therefore, we investigate the Piezo1-mediated mechanisms in mechanical strain-regulated MSC osteogenic differentiation and release of proinflammatory cytokines. The tensile strain was applied to rat MSCs cultured in a monolayer to induce mechanical strain. The immuno-nanomagnetic bead enzyme-linked immunosorbent assay was employed to assess gene and protein expressions, as well as osteogenic biomarkers and interleukin-6 (IL-6) release, both in the presence or absence of a Piezo1 agonist/antagonist. Firstly, biophysical loading through mechanical strain was found to promote MSC osteogenic differentiation. Suppression of Piezo1 using GsMTx4 antagonist or transfection with Piezo1-siRNA effectively inhibited mechanical responses associated with osteogenic gene expressions and IL-6. Activation of Piezo1 by Yoda1 mimicked the effects induced by mechanical strain on osteogenic gene expressions and IL-6 release, which were associated with YAP activation, upregulation, and nuclear accumulation of β-catenin. In conclusion, these findings significantly enhance our understanding of MSC mechanotransduction and hold great promise for drug development to enhance skeletal mass.

Abstract 7079: The Wnt/β-catenin signaling pathway regulates cellular metabolism through the suppression of HAL and ARG1 in liver cancer cells

Abstract Aberrant activation of the Wnt/β-catenin signaling pathway plays a crucial role in a wide range of human tumors including colorectal and liver cancer. The activated signaling causes nuclear accumulation of β-catenin, which leads to the elevated expression of target genes of TCF/LEF (T-cell factor/lymphoid enhancer factor) transcription factors through their interaction with nuclear β-catenin. Recent studies have identified a lot of genes induced by this pathway such as MYC, CCND1, AXIN2, and LGR5, and clarified their roles in tumorigenesis. However, the roles of the genes down-regulated by the pathway remain to be elucidated. Our previous study revealed that the histidine ammonia-lyase gene (HAL) encoding an enzyme involved in the catabolism of histidine was down-regulated by the signaling pathway in liver cancer. In addition, we identified a region that is involved in the Wnt-dependent regulation of HAL. To clarify the regulatory mechanism of HAL by the pathway, we searched for transcription factors that are associated with the regulatory region, and identified CEBPA and FOXA1, two liver-enriched transcription factors. It is of note that the expression of these factors was reduced by the TCF/β-catenin complex. Further investigation identified arginase 1 (ARG1) encoding an enzyme that catalyzes the hydrolysis of arginine as another target gene of CEBPA and FOXA1. Consistent with these data, inhibition of the Wnt signaling increased the expression of ARG1 as well as HAL in liver cancer cells. Furthermore, the up-regulation of HAL and ARG1 by the inhibition of this pathway decreased intracellular concentrations of histidine and arginine, suggesting that the Wnt signaling plays an important role in cellular metabolism through the regulation of the two transcription factors. These findings shed light on the role of the Wnt/β-catenin signaling pathway in the metabolism of amino acids in liver cancer cells. Citation Format: Saya Nakagawa, Kiyoshi Yamaguchi, Kiyoko Takane, Sho Tabata, Tsuneo Ikenoue, Yoichi Furukawa. The Wnt/β-catenin signaling pathway regulates cellular metabolism through the suppression of HAL and ARG1 in liver cancer cells [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 7079.

Abstract 296: BRAFi-induced ROCK-mediated non-canonical nuclear β-catenin shuttling drives a phenotypic switch in cancer-associated fibroblasts

Abstract The discovery of BRAF mutations in around 60% of melanoma patients and the subsequent development of targeted inhibitors to counter the hyperactive BRAF-driven pro-tumorigenic signaling pathway have marked a significant milestone in melanoma therapy. However, despite this progress, the long-term outcomes remain unsatisfactory for many patients due to the occurrence of drug resistance. We previously reported that cancer-associated fibroblasts (CAFs) are stimulated by BRAF inhibitors (BRAFi) to drive matrix remodeling and therapeutic escape pathways in melanoma cells. However, the underlying mechanism by which CAFs are reprogrammed by BRAFi to obtain enhanced phenotypes remains elusive. Here, we present compelling evidence showing that BRAFi (PLX4032), but not CRAF inhibitor (GW5074) or pan-RAF inhibitor (RAF709), induces the accumulation of nuclear β-catenin in CAFs harboring wild-type BRAF, a process mediated by BRAF and CRAF but not ARAF isoform. BRAFi binding to BRAF and CRAF leads to robust RAF kinase dimerization, including BRAF and CRAF homodimer and BRAF: CRAF heterodimer. RAF dimers are subsequently recruited to the plasma membrane, where BRAF and CRAF are phosphorylated on residues Thr599 and Ser338, respectively, and activated in a RAS-GTP-dependent manner. RAF activation stimulates the downstream Rho kinase (ROCK) and MEK/ERK signaling pathways simultaneously. Notably, ablating RAS and RAF isoforms effectively suppressed BRAFi-induced activation of ROCK1/2 signaling in CAFs, further confirming that the ROCK pathway is a downstream effector of BRAFi-driven RAF activation and is intricately linked to increased nuclear β-catenin in CAFs. The pharmacological blockade of ROCK activity, using HA-1077, diminished BRAFi-induced nuclear β-catenin accumulation in CAFs, suggesting BRAFi-driven cytoskeletal remodeling plays a pivotal role in the nuclear shuttling of β-catenin. Using a mouse model that mimics human BRAF-mutant melanoma, we found that elevated level of nuclear β-catenin drives the conversion of fibroblasts into α-SMA-positive CAFs, leading to elevated collagen deposition and contributing to melanoma progression in vivo. In summary, BRAFi reprograms the transcriptional activity in CAFs by driving increased nuclear β-catenin to increase their ability to remodel the tumor ECM and promote melanoma cell proliferation. Collectively, the data offer new insights into the molecular mechanisms that underlie the paradoxical reprogramming of CAFs by BRAFi in melanoma therapy through the non-canonical β-catenin pathway. Citation Format: Bruna da Silva Soley, Radhika Athalye, Ryan Zhang, Thomas Andl, Yuhang Zhang. BRAFi-induced ROCK-mediated non-canonical nuclear β-catenin shuttling drives a phenotypic switch in cancer-associated fibroblasts [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 296.

Unraveling the enigma: A comprehensive review of solid pseudopapillary tumor of the pancreas.

Solid pseudopapillary tumor of the pancreas (SPTP) is a rare neoplasm predominantly observed in young females. Pathologically, CTNNB1 mutations, β-catenin nuclear accumulation, and subsequent Wnt-signaling pathway activation are the leading molecular features. Accurate preoperative diagnosis often relies on imaging techniques and endoscopic biopsies. Surgical resection remains the mainstay treatment. Risk models, such as the Fudan Prognostic Index, show promise as predictive tools for assessing the prognosis of SPTP. Establishing three types of metachronous liver metastasis can be beneficial in tailoring individualized treatment and follow-up strategies. Despite advancements, challenges persist in understanding its etiology, establishing standardized treatments for unresectable or metastatic diseases, and developing a widely recognized grading system. This comprehensive review aims to elucidate the enigma by consolidating current knowledge on the epidemiology, clinical presentation, pathology, molecular characteristics, diagnostic methods, treatment options, and prognostic factors.

Recurrent UBE3C-LRP5 translocations in head and neck cancer with therapeutic implications

Head and neck cancer is a major cause of morbidity and mortality worldwide. The identification of genetic alterations in head and neck cancer may improve diagnosis and treatment outcomes. In this study, we report the identification and functional characterization of UBE3C-LRP5 translocation in head and neck cancer. Our whole transcriptome sequencing and RT-PCR analysis of 151 head and neck cancer tumor samples identified the LRP5-UBE3C and UBE3C-LRP5 fusion transcripts in 5.3% of patients of Indian origin (n = 151), and UBE3C-LRP5 fusion transcripts in 1.2% of TCGA-HNSC patients (n = 502). Further, whole genome sequencing identified the breakpoint of UBE3C-LRP5 translocation. We demonstrate that UBE3C-LRP5 fusion is activating in vitro and in vivo, and promotes the proliferation, migration, and invasion of head and neck cancer cells. In contrast, depletion of UBE3C-LRP5 fusion suppresses the clonogenic, migratory, and invasive potential of the cells. The UBE3C-LRP5 fusion activates the Wnt/β-catenin signaling by promoting nuclear accumulation of β-catenin, leading to upregulation of Wnt/β-catenin target genes, MYC, CCND1, TCF4, and LEF1. Consistently, treatment with the FDA-approved drug, pyrvinium pamoate, significantly reduced the transforming ability of cells expressing the fusion protein and improved survival in mice bearing tumors of fusion-overexpressing cells. Interestingly, fusion-expressing cells upon knockdown of CTNNB1, or LEF1 show reduced proliferation, clonogenic abilities, and reduced sensitivity to pyrvinium pamoate. Overall, our study suggests that the UBE3C-LRP5 fusion is a promising therapeutic target for head and neck cancer and that pyrvinium pamoate may be a potential drug candidate for treating head and neck cancer harboring this translocation.

DPPA2/4 Promote the Pluripotency and Proliferation of Bovine Extended Pluripotent Stem Cells by Upregulating the PI3K/AKT/GSK3β/β-Catenin Signaling Pathway.

Developmental pluripotency-associated 2 (DPPA2) and DPPA4 are crucial transcription factors involved in maintaining pluripotency in humans and mice. However, the role of DPPA2/4 in bovine extended pluripotent stem cells (bEPSCs) has not been investigated. In this study, a subset of bEPSC-related differentially expressed genes (DEGs), including DPPA2 and DPPA4, was identified based on multiomics data (ATAC-seq and RNA-seq). Subsequent investigations revealed that double overexpression of DPPA2/4 facilitates the reprogramming of bovine fetal fibroblasts (BFFs) into bEPSCs, whereas knockout of DPPA2/4 in BFFs leads to inefficient reprogramming. DPPA2/4 overexpression and knockdown experiments revealed that the pluripotency and proliferation capability of bEPSCs were maintained by promoting the transition from the G1 phase to the S phase of the cell cycle. By activating the PI3K/AKT/GSK3β/β-catenin pathway in bEPSCs, DPPA2/4 can increase the nuclear accumulation of β-catenin, which further upregulates lymphoid enhancer binding factor 1 (LEF1) transcription factor activity. Moreover, DPPA2/4 can also regulate the expression of LEF1 by directly binding to its promoter region. Overall, our results demonstrate that DPPA2/4 promote the reprogramming of BFFs into bEPSCs while also maintaining the pluripotency and proliferation capability of bEPSCs by regulating the PI3K/AKT/GSK3β/β-catenin pathway and subsequently activating LEF1. These findings expand our understanding of the gene regulatory network involved in bEPSC pluripotency.

HECW1 restrains cervical cancer cell growth by promoting DVL1 ubiquitination and downregulating the activation of Wnt/β-catenin signaling

HECW1 belongs to ubiquitin ligase (E3) HECT family, and is found to be involved in tumorigenesis and tumor progression. However, the function of HECW1 in cervical cancer (CC) remains unknown. Clinical analysis showed that HECW1 is significantly decreased in CC tumor tissues. Ectopic expression of HECW1 suppressed cell growth, promoting cell cycle arrest and apoptosis in CC cells, while downregulation of HECW1 reversed these trends, impeded proliferation and accelerated cell cycle progression of CC cells. Overexpressing of HECW1 reduced mitochondrial membrane potential and the protein expression of voltage-dependent anion channel 1 (VDAC1). In addition, upregulation of HECW1 inhibited nuclear β-catenin accumulation, downregulated β-catenin/TCF/LEF-mediated transcriptional activity and the expression of downstream gene c-Myc, whereas inhibition of HECW1 received opposite results. Further results confirmed HECW1 affects the protein expression of dishevelled-1 (DVL1), a potent activator of Wnt/β‐catenin, and inhibition of HECW1 inhibited the ubiquitination of DVL1, upregulating its expression. Inhibition of DVL1 restrained the promotion effect of HECW1 suppression on cell proliferation. In vivo experiments also verified that HECW1 suppression promoted the tumor formation of CC cells. Summary, we demonstrated that HECW1 inhibits CC cell proliferation and tumor formation by downregulating DVL1 induced Wnt/β‐catenin signaling pathway activation.

EBP50 Depletion and Nuclear β-Catenin Accumulation Engender Aggressive Behavior of Colorectal Carcinoma through Induction of Tumor Budding.

Ezin-radixin-moesin-binding phosphoprotein 50 (EBP50) is a scaffold protein that interacts with several partner molecules including β-catenin. Here, we examined the crosstalk between EBP50 and nuclear catenin during colorectal carcinoma (CRC) progression. In clinical samples, there were no correlations between the subcellular location of EBP50 and any clinicopathological factors. However, EBP50 expression was significantly lower specifically in the outer areas of tumor lesions, in regions where tumor budding (BD) was observed. Low EBP50 expression was also significantly associated with several unfavorable prognostic factors, suggesting that EBP50 depletion rather than its overexpression or subcellular distribution plays an important role in CRC progression. In CRC cell lines, knockout of EBP50 induced epithelial-mesenchymal transition (EMT)-like features, decreased proliferation, accelerated migration capability, and stabilized nuclear β-catenin due to disruption of the interaction between EBP50 and β-catenin at the plasma membrane. In addition, Slug expression was significantly higher in outer lesions, particularly in BD areas, and was positively correlated with nuclear β-catenin status, consistent with β-catenin-driven transactivation of the Slug promoter. Together, our data suggest that EBP50 depletion releases β-catenin from the plasma membrane in outer tumor lesions, allowing β-catenin to accumulate and translocate to the nucleus, where it transactivates the Slug gene to promote EMT. This in turn triggers tumor budding and contributes to the progression of CRC to a more aggressive phase.

Osteoblast-derived exosomes promote osteogenic differentiation of osteosarcoma cells via URG4/Wnt signaling pathway

Osteosarcoma is a primary malignant bone tumor. Although surgery and chemotherapy are the main treatment methods, the overall curative effect remains unsatisfactory. Therefore, there is an urgent need to develop new therapeutic options for osteosarcoma. In this study, the effect and molecular mechanism of osteoblast-derived exosomes on the treatment of osteosarcoma were evaluated. Human primary osteoblasts were cultured to observe the effects of osteoblast-derived exosomes on the osteogenic differentiation of osteosarcoma cells both in vitro and in vivo. Alizarin red staining and alkaline phosphatase detection were used to evaluate the degree of osteogenic differentiation, and immunofluorescence and Western blotting were used to detect protein expression. The results showed that osteoblast-derived exosomes effectively inhibited the proliferation of osteosarcoma cells and promoted their mineralization in vitro. The exosomes also significantly inhibited tumor growth and promoted tumor tissue mineralization in vivo. Osteoblast-derived exosomes upregulated the expression of bone sialoprotein, osteonectin, osteopontin, runt-related transcription factor 2, and Wnt inhibitory factor 1, downregulated the expression of cyclin D1, and suppressed the nuclear accumulation of β-catenin and promoted its phosphorylation in vitro and in vivo. However, these effects were significantly reversed by upregulated gene (URG) 4 overexpression. These findings suggest that osteoblast-derived exosomes could activate the osteogenic differentiation process in osteosarcoma cells and promote their differentiation by targeting the URG4/Wnt signaling pathway.

THU044 The Subcellular Localization Of β-Catenin Is Associated With Tumor Size And The Surgical Remission Rate In Growth Hormone-producing Pituitary Adenomas

Abstract Disclosure: S. Kuwabara: None. H. Kameda: None. H. Nomoto: None. K. Cho: None. A. Nakamura: None. Y. Ishi: None. H. Motegi: None. F. Miki: None. H. Miyoshi: None. T. Atsumi: None. The Wnt/β-catenin pathway is the best understood Wnt signaling pathway and controls cell proliferation. In the presence of Wnt, the translocation of β-catenin from the cytoplasm to the nucleus leads to pathway activation. It has been reported that the nuclear accumulation of β-catenin is associated with Ki-67 expression in pituitary adenomas and that the invasiveness of growth hormone (GH)-producing pituitary adenomas is associated with β-catenin expression. We aimed to clarify the effects of the Wnt/β-catenin pathway in GH-producing pituitary adenomas. We performed immunofluorescence staining using antibodies against GH and β-catenin in pathological samples of pituitary adenoma from 62 patients with acromegaly who underwent pituitary surgery at our hospital between January 2008 and December 2021. We also obtained clinical data for the patients, including the results of endocrine testing, and evaluated the relationships of key indices with the intracellular localization of β-catenin. Samples from 26 cases (42%) showed strong punctate expression of β-catenin in the nuclei (dot pattern (DP) group), and samples from 36 cases (58%) showed β-catenin expression in the cytoplasm or cell membrane (non-DP group). There were no differences in the sex, age, GH concentration, or insulin-like growth factor I (IGF-1) SD scores of the two groups, but the DP group had larger tumors (diameters 18±8 vs. 13±7 mm) and a higher prevalence of macroadenomas (77% vs. 53%). In the DP group, a paradoxical preoperative GH response (an increase of ≥30% of the basal concentration) to 75-g oral glucose tolerance testing was more frequent (46 vs. 22%, p<0.05) and postoperative remission was less frequent (23% vs. 50%, p<0.05). Accordingly, the Wnt/β-catenin pathway appears to be more active in the DP group. The larger tumors and lower postoperative remission rate of the DP group suggest that the Wnt/β-catenin pathway may influence tumor growth. Wnt/β-catenin pathway could play a major role in GH-producing pituitary tumor growth, therefore this pathway would be a potential therapeutic target in the affected patients. Presentation: Thursday, June 15, 2023

Frequent nuclear β-catenin expression in pulmonary enteric-type adenocarcinoma according to the current World Health Organization criteria.

Based on the current World Health Organization classification criteria, five of 3895 consecutive cases of surgically resected primary lung carcinomas (0.13%) categorized as enteric-type were analyzed. Three cases completely comprised tumor cells that resemble colorectal adenocarcinoma, while the other two cases exhibited features of conventional adenocarcinomas admixed with enteric components. Immunohistochemically, all patients expressed at least three of the five intestinal markers: CDX2, CK20, HNF4α, MUC2, and SATB2. None of the patients expressed TTF-1 and NKX3.1. Three cases showed nuclear accumulation of β-catenin, indicating activation of the Wnt/β-catenin signaling pathway; APC mutations were detected in one of these cases. TP53 mutations were detected in three cases. Mutated EGFR or ALK fusions were not detected. Our study demonstrates that pulmonary enteric-type adenocarcinomas share immunohistochemical features and genetic alterations with colorectal adenocarcinomas, which are characterized by frequent activation of the Wnt/β-catenin signaling pathway and a lack of actionable mutations.

A patient-derived organoid-based study identified an ASO targeting SNORD14E for endometrial cancer through reducing aberrant FOXM1 Expression and β-catenin nuclear accumulation

BackgroundMost of the endometrial cancer (EC) patients are diagnosis in early stage with a good prognosis while the patients with locally advanced recurrent or metastatic result in a poor prognosis. Adjuvant therapy could benefit the prognosis of patients with high-risk factors. Unfortunately, the molecular classification of great prognostic value has not yet reached an agreement and need to be further refined. The present study aims to identify new targets that have prognostic value in EC based on the method of EC patient-derived organ-like organs (PDOs), and further investigate their efficacy and mechanism.MethodsThe Cancer Genome Atlas (TCGA) database was used to determine SNORD14E expression. The effects of SNORD14E were investigated using CCK8, Transwell, wound-healing assays, and a xenograft model experiment; apoptosis was measured by flow cytometry. Antisense oligonucleotide (ASO) targeting SNORD14E was designed and patient-derived organoids (PDO) models in EC patients was established. A xenograft mouse and PDO model were employed to evaluate the effects of ASO targeting SNORD14E. RNA-seq, Nm-seq, and RNA immunoprecipitation (RIP) experiments were employed to confirm the alternative splicing (AS) and modification induced by SNORD14E. A minigene reporter gene assay was conducted to confirm AS and splicing factors on a variable exon. Actinomycin-d (Act-D) and Reverse Transcription at Low deoxy-ribonucleoside triphosphate concentrations followed by PCR (RTL-P) were utilized to confirm the effects of 2′-O methylation modification on FOXM1.ResultsWe found that SNORD14E was overexpressed in EC tissues and patients with high expressed SNORD14E were distributed in the TCGA biomolecular classification subgroups without difference. Further, SNORD14E could reduce disease-free survival (DFS) and recurrence free survival (RFS) of EC patients. SNORD14E promoted proliferation, migration, and invasion and inhibited the apoptosis of EC cells in vitro. ASOs targeting SNORD14E inhibited cell proliferation, migration, invasion while promoted cell apoptosis. ASOs targeting SNORD14E inhibited tumor growth in the xenograft mouse model. TCGA-UCEC database showed that the proportion of patients with high expression of SNORD14E in middle-high risk and high-risk patients recommended by EMSO-ESGO-ESTRO guidelines for adjuvant therapy is more than 50%. Next, we enrolled 8 cases of high-risk and high-risk EC patients according to EMSO-ESGO-ESTRO guidelines and successfully constructed EC-PDOs. ASOs targeting SNORD14E inhibited the EC-PDO growth. Mechanistically, SNORD14E could recognize the mRNA of FOXM1 and recruit SRSF1 to promote the shearing of the variable exon VIIa of FOXM1, resulting in the overexpression of the FOXM1 malignant subtypes FOXM1b and FOXM1c. In addition, SNORD14E modified FOXM1 mRNA with 2`-O-methylation, which prolonged the half-life of FOXM1 mRNA. The nucleus accumulation of β-catenin caused by aberrant FOXM1 expression led to EC progression.ConclusionsASO targeting SNORD14E can be an effective treatment for EC.

Anticancer Effect of Gallic Acid on Acidity-Induced Invasion of MCF7 Breast Cancer Cells.

The acidic tumor environment has emerged as a crucial factor influencing the metastatic potential of cancer. We investigated the effect of an acidic environment on the acquisition of metastatic properties in MCF7 breast cancer cells and explored the inhibitory effects of gallic acid. Prolonged exposure to acidic culture conditions (over 12 weeks at pH 6.4) induced the acquisition of migratory and invasive properties in MCF7 cells, accompanied by increased expression of Matrix Metalloproteinase 2 and 9 (MMP2 and MMP9, respectively), together with alterations in E-cadherin, vimentin, and epithelial-to-mesenchymal transition markers. Gallic acid effectively inhibited the survival of acidity-adapted MCF7 (MCF7-6.4/12w) cells at high concentrations (>30 μM) and reduced metastatic characteristics induced by acidic conditions at low concentration ranges (5-20 μM). Moreover, gallic acid suppressed the PI3K/Akt pathway and the nuclear accumulation of β-catenin, which were elevated in MCF7-6.4/12w cells. These findings highlight the potential of gallic acid as a promising therapeutic agent for metastatic traits in breast cancer cells under acidic conditions.

Neurogenesis redirects β-catenin from adherens junctions to the nucleus to promote axonal growth.

Here, we show that, in the developing spinal cord, after the early Wnt-mediated Tcf transcription activation that confers dorsal identity to neural stem cells, neurogenesis redirects β-catenin from the adherens junctions to the nucleus to stimulate Tcf-dependent transcription in a Wnt-independent manner. This new β-catenin activity regulates genes implicated in several aspects of contralateral axon growth, including axon guidance and adhesion. Using live imaging of ex-vivo chick neural tube, we showed that the nuclear accumulation of β-catenin and the rise in Tcf-dependent transcription both initiate before the dismantling of the adherens junctions and remain during the axon elongation process. Notably, we demonstrated that β-catenin activity in post-mitotic cells depends on TCF7L2 and is central to spinal commissural axon growth. Together, our results reveal Wnt-independent Tcf/β-catenin regulation of genes that control the growth and guidance of commissural axons in chick spinal cord.

Adenoid Ameloblastoma Shares Clinicopathologic, Immunohistochemical, and Molecular Features With Dentinogenic Ghost Cell Tumor: A Comparative Analysis.

The updated classification of odontogenic tumors by the World Health Organization (WHO) has included adenoid ameloblastoma (AA) as a distinct entity. However, distinguishing between AA and dentinogenic ghost cell tumor (DGCT) can still be challenging due to their significant morphologic similarities. In this study, we aimed to compare the clinicopathologic, immunohistochemical, and molecular characteristics of AA and DGCT to aid in their differentiation and to shed light on their pathologic mechanisms. Thirteen cases of AA and 14 cases of DGCT (15 samples) were analyzed, along with 11 cases of adenomatoid odontogenic tumor (AOT) and 18 cases of conventional ameloblastoma (AM) for comparative purposes. The study found that AA and DGCT shared a similar long-term prognosis. Immunohistochemically, all cytokeratins detected, except CK8/18, were not statistically significant in differentiating AA and DGCT, while there was a statistically significant difference in the immunophenotype of CK7 and CK10/13 between AA and AM. Nuclear β-catenin accumulation were detected in all cases of AA and DGCT, while AOTs and AMs exhibited cytoplasmic β-catenin. Molecularly, CTNNB1 hotspot mutations were found in only 1 case of AA (1/13), but not found in the other 3 types of tumors. BRAF p.V600E mutation was positive in 2/13 (15%) AA, 1/15 (7%) DGCT, and 2/11 (18%) AOT cases. In comparison, conventional AM was positive for BRAF p.V600E mutation in 94% (17/18) of cases, while KRAS mutations were detected in 63% (7/11) of AOT cases. The study suggests that the so-called AA is a rare benign tumor that exhibits clinical, immunohistochemical, and molecular features similar to DGCTs. Based on these findings, AA should not be categorized as a standalone entity solely based on the presence of whorls/morules and cribriform/duct-like structures. Further studies are needed to investigate the pathologic mechanisms of these tumors and to identify potential therapeutic targets.

Establishment and characterization of a novel cell line and xenotransplant mouse model derived from feline colorectal adenocarcinoma.

Colorectal adenocarcinoma is an aggressive malignant tumor in cats that frequently metastasizes to the lymph nodes and/or distant organs. However, research on feline colorectal adenocarcinoma is limited, and experimental models have not been established. A novel cell line, FeLeco-G7, was established from the lymph node of a 12-year-old spayed female Maine Coon cat with metastatic colorectal adenocarcinoma. FeLeco-G7 cells were polygonal with abundant cytoplasm and adherent growth. The population-doubling time was approximately 28.3 hours, and the mean number of chromosomes was 37.6±0.1 per cell (ranging between 32 and 41). Consistent with the original tumor, FeLeco-G7 cells were immunopositive for cytokeratin (CK) 20 and CDX2, and immunonegative for CD10 and CK7. Nuclear accumulation of β-catenin was rarely observed. Mutation analysis suggested TP53 gene alterations. A subcutaneous injection of FeLeco-G7 cells into immunodeficient mice resulted in the formation of a mass at the injection site without the development of metastatic lesions. An orthotopic (intrarectal) transplantation of FeLeco-G7 cells caused cachexia and diffuse involvement of the rectal mucosa in one of the 3 mice and the formation of masses around the rectum in the other 2 mice. Metastases to the regional lymph nodes and lungs were detected in three of the 3 and one of the 3 mice, respectively. The histological findings and immunohistochemical features of these masses were similar to those of the original tumor. These results suggest that FeLeco-G7 cells and the orthotopically transplanted mouse model are valuable tools for further molecular and therapeutic research on feline colorectal adenocarcinoma.