Expression Of Β-catenin Research Articles

17β-Estradiol promotes metastasis in triple-negative breast cancer through the Calpain/YAP/β-catenin signaling axis.

β-catenin is an important regulator of malignant progression. 17β-Estradiol (E2), an important sex hormone in women, promotes the growth and metastasis of triple-negative breast cancer (TNBC). However, whether β-catenin is involved in E2-induced metastasis of TNBC remains unknown. In this study, we show that E2 induces the proliferation, migration, invasion, and metastasis of TNBC cells. E2 induces β-catenin protein expression and nuclear translocation, thereby regulating the expression of target genes such as Cyclin D1 and MMP-9. The inhibition of β-catenin reversed the E2-induced cell malignant behaviors. Additionally, E2 activated Calpain by increasing intracellular Ca2+ levels and reducing calpastatin levels. When Calpain was inhibited, E2 did not induce the proliferation, migration, invasion, or metastasis of TNBC cells. In addition, E2 promoted translocation of YAP into the nucleus by inhibiting its phosphorylation. Calpain inhibition reversed the E2-induced YAP dephosphorylation. Inhibition of YAP transcriptional activity reversed the effects of E2 on the proliferation, migration, invasion, and β-catenin of TNBC cells. In conclusion, we demonstrated that E2 induced metastasis-related behaviors in TNBC cells and this effect was mediated through the Calpain/YAP/β-catenin signaling pathway.

Urine-derived exosomes and their role in modulating uroepithelial cells to prevent hypospadias

PurposeUrethral hypospadias, a common congenital malformation in males, is closely linked with disruptions in uroepithelial cell (UEC) processes. Evidence exists reporting that urine-derived exosomes (Urine-Exos) enhance UEC proliferation and regeneration, suggesting a potential role in preventing hypospadias. However, the specific influence of Urine-Exos on urethral hypospadias and the molecular mechanisms involved are not fully understood. This study focuses on investigating the capability of Urine-Exos to mitigate urethral hypospadias and aims to uncover the underlying molecular mechanisms. MethodsBioinformatics analysis was performed to identify key gene targets in Urine-Exos potentially involved in hypospadias. Subsequent in vitro and in vivo experiments were conducted to validate the regulatory effects of Urine-Exos on hypospadias. ResultsBioinformatics screening revealed syndecan-1 (SDC1) as a potential pivotal gene for the prevention of hypospadias. In vitro experiments demonstrated that Urine-Exos enhanced the proliferation and migration of UECs by transferring SDC1 and inhibiting cell apoptosis. Notably, Urine-Exos upregulated β-catenin expression through SDC1 transfer, further promoting UEC proliferation and migration. These findings were confirmed in a congenital hypospadias rat model induced by di(2-ethylhexyl) phthalate (DEHP). ConclusionThis study reveals the therapeutic potential of Urine-Exos in hypospadias, mediated by the SDC1/β-catenin axis. Urine-Exos promote UEC proliferation and migration, thereby inhibiting the progression of hypospadias. These findings offer new insights and potential therapeutic targets for the management of congenital malformations.

β-Catenin alterations in testicular Leydig cell tumour: a immunohistochemical and molecular analysis.

Testicular Leydig cell tumours (LCTs) are the most common type of sex cord-stromal tumour in men, representing 1%-3% of all testicular neoplasms. Among testicular sex cord-stromal tumours, CTNNB1 mutations and nuclear expression of β-catenin have been typically associated with Sertoli cell tumour. Recent genomic analyses have shown that CTNNB1 variants are also identified in a subset of LCTs; however, the frequency and clinicopathologic associations of β-catenin alterations remain incompletely understood in this tumour type. In this study, we evaluated 32 LCTs (five malignant/metastasizing, 27 nonmetastasizing) using β-catenin immunohistochemistry and DNA sequencing. Immunohistochemistry revealed focal or multifocal nuclear β-catenin expression in 47% of the tumours. Diffuse nuclear β-catenin expression (in >50% of the tumour cells) was not detected in any of the cases analysed herein. Comparison of β-catenin-positive and β-catenin-negative cases did not show significant differences in the frequency of adverse histopathologic findings or malignant clinical behaviour. DNA sequencing performed de novo on a subset of seven cases revealed the presence of exon 3 CTNNB1 variants in four of them (4/7, 57%), with variant allele frequencies (VAF) ranging from 7 to 33%. Two additional β-catenin-positive cases that had been sequenced as part of a previous study harboured exon 3 CTNNB1 variants at VAF of 28% and 7%, respectively. These results demonstrate that β-catenin alterations are relatively common in LCT, most likely occurring as subclonal events that are not enriched in cases with aggressive features. Further studies are needed to clarify the oncogenic role of β-catenin in this tumour type.

Knocking Down HN1 Blocks Helicobacter pylori-Induced Malignant Phenotypes in Gastric Mucosal Cells and Inhibits Gastric Cancer Cell Proliferation, Cytoskeleton Remodeling, and Migration.

Helicobacter pylori (H. pylori) is implicated in the aberrant proliferation and malignant transformation of gastric mucosal cells, heightening the risk of gastric cancer (GC). HN1 is involved in the development of various tumors. However, precise mechanistic underpinnings of HN1 promoting GC progression in H. pylori remain elusive. The study collected 79 tissue samples of GC patients, including 47 with H. pylori-positive GC and 32 H. pylori-negative controls. Using human gastric epithelial cells (GES-1) and human gastric adenocarcinoma cells (HGC-27), the effect of overexpression / knocking down of HN1 and H. pylori infection was evaluated on cell function (proliferation, migration, apoptosis), cytoskeleton, and expression of cell malignant phenotype factors that promote the malignant biological behavior of cancer cells. The expression of HN1 in GC tissues is higher than that in paracancerous tissue and is closely related to infiltration, lymphatic metastasis, distant metastasis, survival, and H. pylori infection. Downregulation of HN1 effectively hinders the ability of H. pylori strains 26695 and SS1 to promote migration of GES-1 and HGC-27 cells, while lowering the expression of key indicators associated with malignant phenotype. Downregulated GSK3B, β-catenin, and Vimentin after knockdown Integrinβ1, but HN1 expression remained largely unchanged, when HN1 and Integrinβ1 were knocked down, GSK3B, β-catenin, and Vimentin expression were considerably reduced. Our research demonstrated the crucial role of HN1 in H. pylori-induced acquisition of a malignant phenotype in GES-1 cells. Knockdown of HN1 blocked the pathogenic mechanism of H. pylori-induced GC and downregulated the expression of GSK3Β, β-catenin and Vimentin via Integrin β1.

The Role of Heat-Induced Stress Granules in the Blood-Testis Barrier of Mice.

Stress granules (SGs) are membraneless ribonucleoprotein (RNP)-based cellular foci formed in response to stress, facilitating cell survival by protecting against damage. Mammalian spermatogenesis should be maintained below body temperature for proper development, indicating its vulnerability to heat stress (HS). In this study, biotin tracer permeability assays showed that the inhibition of heat-induced SG assembly in the testis by 4-8 mg/kg cycloheximide significantly increased the percentage of seminiferous tubules with a damaged blood-testis barrier (BTB). Western blot results additionally revealed that the suppression of heat-induced SG assembly in Sertoli cell line, TM4 cells, by RNA inference of G3bp1/2 aggravated the decline in the BTB-related proteins ZO-1, β-Catenin and Claudin-11, indicating that SGs could protect the BTB against damage caused by HS. The protein components that associate with SGs in Sertoli cells were isolated by sequential centrifugation and immunoprecipitation, and were identified by liquid chromatography with tandem mass spectrometry. Gene Ontology and KEGG pathway enrichment analysis revealed that their corresponding genes were mainly involved in pathways related to proteasomes, nucleotide excision repair, mismatch repair, and DNA replication. Furthermore, a new SG component, the ubiquitin associated protein 2 (UBAP2), was found to translocate to SGs upon HS in TM4 cells by immunofluorescence. Moreover, SG assembly was significantly diminished after UBAP2 knockdown by RNA inference during HS, suggesting the important role of UBAP2 in SG assembly. In addition, UBAP2 knockdown reduced the expression of ZO-1, β-Catenin and Claudin-11, which implied its potential role in the function of the BTB. Overall, our study demonstrated the role of SGs in maintaining BTB functions during HS and identified a new component implicated in SG formation in Sertoli cells. These findings not only offer novel insights into the biological functions of SGs and the molecular mechanism of low fertility in males in summer, but also potentially provide an experimental basis for male fertility therapies.

Abstract 164: Genetic elimination of β-catenin using a doxycycline-regulated GEM model fails to restore checkpoint blockade efficacy due to persistent M2-like macrophages

Abstract Response to checkpoint blockade immunotherapy (CBI) is not universal, partly due to a wide variation in baseline immune cell infiltration in the tumor microenvironment (TME). One mechanism contributing to this variability is tumor cell-intrinsic activation of the β-catenin signaling pathway, which has previously been shown to result in a non-T cell-inflamed TME. Constitutive β-catenin signaling resulted in reduced Batf3-lineage dendritic cell (cDC1) recruitment, leading to reduced T cell activation and infiltration and loss of anti-CTLA-4+anti-PD-L1 therapeutic efficacy. Efforts to target the Wnt/β-catenin pathway to enhance immune responses in β-catenin-active tumors have seen limited success. A genetic experiment eliminating β-catenin expression after establishment of a non-T cell-inflamed TME might illustrate the maximal biologic effect that could be expected with blockade of the pathway. We developed a genetically engineered mouse (GEM) model that allows for dynamic regulation of β-catenin on and off. This model employs tyrosinase-driven tamoxifen-regulated Cre-recombinase to activate the BRAF V600E oncogene and delete the tumor suppressor gene PTEN, along with a transactivator for doxycycline-regulated expression of a non-degradable β-catenin. Topical application of 4-hydroxytamoxifen resulted in melanoma formation, and administration of doxycycline resulted in robust nuclear expression of melanocyte-specific β-catenin compared to non-treated controls. This was accompanied by a significant reduction in CD3+ T cell infiltration within the TME, confirming the link between active β-catenin signaling and T cell exclusion. Discontinuing doxycycline treatment led to complete reduction of nuclear β-catenin expression in the tumor cells within seven days and a substantial return of CD3+ T cells into the TME. However, despite the re-infiltration of CD3+ T cells, the tumors previously expressing β-catenin (ex-β-catenin tumors) did not regain therapeutic responsiveness to anti-CTLA-4+anti-PD-L1. Single cell RNA sequencing of the ex-β-catenin tumors indicated the presence of an immunosuppressive-like macrophage population, characterized by the expression of Ccl8, Gas6 and Cd163. This finding suggests that the prior presence of β-catenin may induce long-lasting changes in the TME that suppress the immune response even after β-catenin levels are reduced. These data corroborate previous findings on the role of β-catenin in modulating the immunological landscape of melanoma and extend it by demonstrating the long-term persistence of immune evasion by suppressive myeloid cells even after β-catenin signaling is eliminated. These insights have implications for clinical strategies aiming to block Wnt/β-catenin signaling, which may additionally require myeloid cell modulation to restore immunotherapy efficacy. Citation Format: Alexandra Cabanov, Ruxandra Tonea, Jason Shapiro, Anna Martinez, Yuanyuan Zha, Thomas F. Gajewski. Genetic elimination of β-catenin using a doxycycline-regulated GEM model fails to restore checkpoint blockade efficacy due to persistent M2-like macrophages [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 164.

Abstract 2784: Fatty acid synthase enhances stem-like properties of normal intestinal and colorectal cancer cells via an increase in notum expression and secretion

Abstract Introduction: Overexpression of lipogenic enzymes has been associated with a poor clinical outcome in colorectal cancer (CRC). Fatty acid synthase (FASN) synthesizes palmitate which can be utilized for post-translational modifications of various proteins. Notum, a palmitoleoyl-protein, prevents the downstream activation of Wnt signaling by de-palmitoylating Wnt ligands. Notum is also a CRC stem cell marker, and its expression correlates with poor prognosis in CRC. We found that upregulation of FASN is associated with an increase in Notum expression in mouse adenoma tissues. Therefore, the purpose of this study is to elucidate the mechanisms and contribution of FASN/Notum axis in CRC. Methods: Adenoma and normal intestinal organoids, established from ApcMin/VillinCre-ERT2 and Apc/VillinCre-ERT2 mouse models with hetero- and homozygous deletion of FASN. 4-hydroxytamoxifen (4-OHT) and TVB-3664 (FASN inhibitor) treatments were used to assess the effect of FASN deletion/inhibition on organoid growth and viability. LIVE/DEAD™ Viability/Cytotoxicity and Cell Titer-Glo® 3D Cell Viability Assays were used for quantitative analysis of growth. Human NOTUM/Protein notum homolog ELISA Kit was used to analyze Notum secretion. CRC cells, NTC and FASN shRNA, and control and FASN overexpression, were used for Notum analysis. Results: The TCGA data analysis shows that Notum is significantly upregulated in CRC and its expression correlates with expression of FASN in tumor tissue. Utilizing qRT-PCR and Western blot analyses, we show that downregulation of FASN leads to a decrease in expressions of active β-catenin, Notum, and other stem cell markers in transgenic mouse models. Moreover, 4-OHT-mediated inhibition of FASN results in decrease viability and size in ApcMin/FASN/VillinCre-ERT2 and Apc/FASN/VillinCre-ERT2 organoids. Consistently, shRNA-mediated deletion of FASN decreases expression of Notum in CRC cells. In contrast, overexpression of FASN increases the expression levels of active and total β-catenin, Notum, and other stem cell markers in SW480 cells. We show that normal epithelial cells exposed to CRC cell medium exhibit stem-like phenotype which is reduced when cells are exposed to medium collected from Notum shRNA knockdown cells. Moreover, the addition of recombinant Notum restores this phenotype. Conclusion: In summary, downregulation of FASN leads to a decrease in expression of Notum and is associated with morphological changes and significant decrease in viability in organoid models. Conversely, FASN overexpression upregulates Notum expression suggesting a potential cross talk between de novo lipid synthesis and Notum. Delineating the role of FASN regulation of stem-like properties via upregulation of β-catenin signaling and expression of Notum and other stem cell markers will provide the rationale for targeting the FASN/Notum axis in CRC. Citation Format: Courtney Olivia Kelson, Josiane Weber Tessmann, Daheng He, Chi Wang, Yekaterina Zaytseva. Fatty acid synthase enhances stem-like properties of normal intestinal and colorectal cancer cells via an increase in notum expression and secretion [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 2784.

Abstract 4671: Efficacy and mechanism of mebendazole for ovarian cancer therapy

Abstract Introduction: Ovarian cancer (OvCa) is the most lethal gynecological malignancy. Although most OvCa patients initially respond to frontline platinum-based therapies with approximately 80% of patients experiencing remission, approximately 75% of those women experience a recurrence with only approximately 50% of patients alive 5 years following diagnosis. There is a critical need to develop novel therapeutic agents or methods to overcome chemoresistance and toxicities experienced with conventional chemotherapy regimens used for OvCa patients. Repurposing drugs is a promising strategy to safely and more rapidly evaluate potentially effective treatment regimens. Over the past two decades, Mebendazole (MBZ), an anti-parasitic drug, has gained much attention in oncology due to its favorable biosafety profile and potent anti-cancerous activity seen in several human malignancies. Therefore, we examined the efficiency and mechanism of MBZ against OvCa. Methods: The in vitro efficacy of MBZ was evaluated in cisplatin-resistant (CPR) and parent (WT/sensitive) OVCAR-8 cell lines as well as in ascites samples collected from chemo-resistant OvCa patients by using 2D and/or 3D cell viability assay and invasion assay. The in vivo efficacy of MBZ was assessed in orthotopic animal models, utilizing CPR-OVCAR8 spheroids, and patient-derived xenograft (PDX) animal models with specimens from chemo-resistant ovarian cancer patients. Molecular mechanisms were investigated through western blot and immunofluorescence analysis. Result: Our results confirmed that MBZ efficiently decreased cell viability, spheroid size, and the invasion ability of OvCa cell lines and ascites samples. OvCa cells treated with MBZ demonstrated downregulation of proliferation markers and upregulation of apoptosis markers indicating inhibition of cell proliferation and induction of apoptosis. Mechanistically, MBZ inhibited the Wnt/β-catenin signaling pathway by downregulating the expression and nuclear localization of β-catenin and epithelial-mesenchymal transition (EMT) markers. Preclinical studies showed that MBZ at 50 mg/kg/day dose for 28 days significantly reduced tumor growth in PDXs and orthotopic tumor models without any evidence of toxicity. Conclusion: Collectively, our study strongly supports the therapeutic potential of MBZ against OvCa particularly, which warrants further clinical studies. Citation Format: Rajani Rai, Dhanamjai Penta, Debasish Dey, Doris M Benbrook, Lin Wang, Magdalena Bieniasz, Lauren E Dockery. Efficacy and mechanism of mebendazole for ovarian cancer therapy [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 4671.

Abstract 7579: Dual inhibition of enhancer of zeste homolog 1 2 induces pyroptosis, modulates oncogenic signaling pathways & sensitizes hepatocellular carcinoma to valemetostat & docetaxel treatments

Abstract HCC is a global health concern, with chemotherapy resistance and patient recurrence posing significant challenges to liver cancer treatment. EZH2 is a crucial part of the polycomb repressive complex 2 (PRC2). It, along with its homolog EZH1, is a focus for cancer therapeutic targets. Dysregulation of EZH1/2 can cause cancer development due to significant changes in geneexpression. The current study aims to investigate the interaction between EZH1/2 and oncogenic signals responsible for HCC progression and pyroptosis induction. Two cell lines, HepG2 and SK-Hep1, were subjected to two FDA-approved drugs, Valemetostat (Val) and Docetaxel (Doc), to determine the impact of EZH1/2 on tumorigenicity and drug resistance. The WST-1 assay was utilized to gauge cell proliferation. The results indisputablydemonstrated a synergistic effect of the drugs after 48 h of treatment. The inhibition of viability was attributed to apoptosis induction in both tested cell lines, and the maximum effect was observed in the combined treatment as compared to either the control or each drug alone. Furthermore, our datashowed activation of caspase-3, upregulation of BAX, indicating apoptotic induction, and downregulation of Bcl-2, Bcl-XL, AKT, S6k, oncogenic β-catenin, and Stat3 protein expression levels, suggesting a modulation of oncogenic signaling pathways at the protein level. After 24 h of Val/Doc treatment, pyroptosis was observed, characterized by cell swelling and bubbles on themembrane and a significant release of lactate dehydrogenase, indicating pyroptotic cell cytotoxicity. The antitumor effects and pyroptosis were enhanced by using a dual inhibitor, UNC1999, for EZH1/2, resulting in a marked increase in the sensitivity of tested cells to the Val/Doc treatment invitro. The present study unequivocally demonstrated that dual inhibition of EZH1/2 acts as a potent sensitizer of HCC cells to Val/Doc treatment, which might be a promising therapeutic approach for inducing cellular pyroptosis in HCC cell lines. Citation Format: Asmaa Elkhder Harira, Adham Maher, Ahmed Sultan. Dual inhibition of enhancer of zeste homolog 1 2 induces pyroptosis, modulates oncogenic signaling pathways & sensitizes hepatocellular carcinoma to valemetostat & docetaxel treatments [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 7579.

Abstract 7589: The novel complex delivery system of C-phycocyanin-loaded klebsiella pneumoniabacterial ghost induces apoptosis and sensitizes non-small cell lung cancer cell lines to doxorubicin

Abstract Lung cancer is a significant cause of cancer-related deaths worldwide, with a high incidence rate, poor prognosis, aggressiveness, and a lack of effective treatment options. The present study has brought together two FDA-approved drugs with antineoplastic properties to create a complex that promises to revolutionize the treatment of Non-Small Cell Lung Cancer (NSCLC). By combining C-Phycocyanin extract (PCE), a pigment-protein complex synthesized by blue-green microalgae platensis, with the immunostimulatory doxorubicin (DOX) loaded Bacterial Ghosts (BGs), the present study aims to achieve enhanced dual-chemotherapy and remarkable inhibition of DOX-chemoresistance. The BG delivery system uses purified bacterial cell evacuation and safe confirmed Klebsiella pneumoniae BGs (KPBG) for safe and effective delivery, overcoming issues with resistance and poor delivery. The complex delivery system of KPBG-PCE/DOX was tested on two NSCLC cell lines, wild-P53, A549, and mutant-P53, NCI/H358, respectively. Our data showed that the loaded combined treatment significantly induced morphological changes with signs of apoptosis induction in the tested cell lines compared with the control. The WST-1 assay was used to evaluate cell proliferation. Data indicates that PCE and DOX have a synergistic effect at low concentrations when loaded on KPBGs for a constant count of BGs CFU/ml after 48 h of treatment. The viability inhibition and apoptosis induction of A549 and NCI/H358 cells were amplified in the combined treatment of 48 h compared to the control or either each drug alone. At the protein levels, our data showed activation of caspase-3, upregulation of BAX, and downregulation of Bcl-2, Bcl-XL, m-TOR, S6k, oncogenic β-catenin, and cyclin-D1 protein expression levels after treatment with (KPBG-PCE/DOX) for 48 h, indicating apoptotic induction and modulating oncogenic signaling pathways. In conclusion, the current study presents a promising outcome of a synergistic delivery system of KPBG-PCE/DOX that can inhibit lung cancer cell line proliferation, induce apoptosis, and increase cell sensitivity to DOX. The KPBG delivery system offers an appealing approach for a successful combination of targeted therapy for lung cancer. Citation Format: Basma Adel Elsayed Abdelaziz, Hoda Eid Mahmoud, Omayma Mohamed Sadek, Ahmed Samir Sultan. The novel complex delivery system of C-phycocyanin-loaded klebsiella pneumoniabacterial ghost induces apoptosis and sensitizes non-small cell lung cancer cell lines to doxorubicin [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 7589.

Abstract 249: Deciphering the impact of TRIB3-ELF4 interaction in regulating CDK6 on cancer stem cell activity in endometrial cancer

Abstract Background: Endometrial cancer (EC) is the most common gynecological tumor among women worldwide, posing a serious threat to women's health. ELF4 (E74 like ETS transcription factor 4), a member of the ETS family, plays a role in facilitating cancer progression. Our previous work demonstrated the role of direct binding between ELF4 and tribbles pseudokinase 3 (TRIB3) in promoting β-catenin expression. In this study, we further explore ELF4's involvement in the maintenance of cancer stem cells (CSCs) in EC. Methods: The vital role of ELF4 in EC was determined through gain- and loss-of-function assays. ELF4 was silenced in two EC cell lines, AN3CA and HEC-1A, and primary EC cells from a Taiwanese patient (EMC6), using RNA interference techniques. The expression of ELF4, TRIB3, and CDK6 in human EC samples was assessed using immunohistochemistry. Tumorsphere formation assays, quantitative real-time PCR, and immunoblotting quantified CSC activity and the involvement of related signaling pathways. Transcriptional regulation associated with ELF4 was investigated using luciferase reporter assays and chromatin immunoprecipitation. Results: Analysis of the TCGA database via the TISIDB web tool revealed that elevated ELF4 levels correlated with higher histological grades, advanced clinical stages, and poorer overall survival in EC patients. A grade-dependent increase in ELF4 expression was observed using tissue microarrays. Knockdown of ELF4 in EC cell lines and patient-derived EC cells significantly reduced cell proliferation, cell cycle progression, migration, invasion, and CSC activity. RNA-seq data analysis of ELF4-knockdown EC cells identified CDK6 as a potential downstream target of the ELF4/TRIB3 interaction. Knockdown of ELF4 and TRIB3 significantly downregulated CDK6 expression. Co-expression of TRIB3 and ELF4 enhanced CDK6 expression, and their expression was positively associated with CDK6 in EC specimens. We also demonstrated that CDK6 facilitates EC-CSC activity. Knockdown of CDK6 significantly attenuated tumorsphere formation and reduced the levels of cancer stemness-related proteins, including OCT4, NANOG, and c-MYC. Conclusion: Our study demonstrates the essential roles of ELF4 and TRIB3 in regulating CDK6 expression, contributing to the maintenance of EC-CSCs. Citation Format: Wen-Ling Wang, Wen-Wei Chang. Deciphering the impact of TRIB3-ELF4 interaction in regulating CDK6 on cancer stem cell activity in endometrial cancer [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 249.

Morules and β-catenin predict POLE mutation status in endometrial cancer: A pathway to more cost-effective diagnostic procedures.

The characterization of DNA polymerase epsilon (POLE) mutations has transformed the classification of endometrial endometrioid carcinomas (EECs), highlighting the need for efficient identification methods. This study aims to examine the relationship between distinct morphologic features-namely, squamous morules and squamous differentiation (SD), as well as β-catenin expression-and the POLE mutation status in endometrial cancer (EC). Our study included 35 POLE-mutated (POLEmut) EC cases and 395 non-POLEmut EEC cases. Notably, we observed no presence of morules in POLEmut cases, while SD was identified in 20% of instances. Conversely, morules and SD were identified in 12.7% and 26.1% of non-POLEmut EC cases, respectively, with morules consistently linked to a POLE wild-type status. The nuclear β-catenin expression is typically absent in tumors with wild-type POLE (wt-POLE) status. Our findings suggest that the presence of either morules or nuclear β-catenin expression in EEC could practically rule out the presence of POLE mutations. These morphologic and immunohistochemical features can be used as preliminary screening tools for POLE mutations, offering significant savings in time and resources and potentially enhancing clinical decision-making and patient management strategies. However, further validation in larger, multi-institutional studies is required to fully understand the implications of these findings on clinical practice.

Ocu-miR-10a-5p promotes the chondrogenic differentiation of rabbit BMSCs by targeting BTRC-mediated Wnt/β-catenin signaling pathway.

MicroRNAs (miRNAs) play an important role in articular cartilage damage in osteoarthritis (OA). However, the biological role of miRNAs in the chondrogenic differentiation of bone marrow mesenchymal stem cell (BMSC) remains largely unclear. Rabbit bone marrow mesenchymal stem cells (rBMSCs) were isolated, cultured, and identified. Afterwards, rBMSCs were induced to chondrogenic differentiation, examined by Alcian Blue staining. Differentially expressed miRNAs were identified in rBMSCs between induced and non-induced groups by miRNA sequencing analysis, part of which was validated via PCR assay. Cell viability and apoptosis were assessed by CCK-8 assay and Hoechst staining. Saffron O staining was utilized to assess chondrocyte hyperplasia. The expression of specific chondrogenic markers, including COL2A1, SOX9, Runx2, MMP-13, Aggrecan, and BMP-2, were measured at mRNA and protein levels. The association between beta-transducin repeat containing E3 ubiquitin protein ligase (BTRC) and miR-10a-5p in the miRNA family from rabbit (ocu-miR-10a-5p) was determined by luciferase reporter assay. A total of 76 differentially expressed miRNAs, including 52 downregulated and 24 upregulated miRNAs, were identified in rBMSCs from the induced group. Inhibition of ocu-miR-10a-5p suppressed rBMSC viability and chondrogenic differentiation, as well as downregulated the expression of β-catenin, SOX9, COL2A1, MMP-13, and Runx2. BTRC was predicted and confirmed as a target of ocu-miR-10a-5p. Overexpression of BTRC rescued the promoting impacts of overexpressed ocu-miR-10a-5p on chondrogenic differentiation of rBMSCs and β-catenin expression. Taken together, our data suggested that ocu-miR-10a-5p facilitated rabbit BMSC survival and chondrogenic differentiation by activating Wnt/β-catenin signaling through BTRC.

THZ2 Ameliorates Mouse Colitis and Colitis-Associated Colorectal Cancer.

Colorectal cancer is a global malignancy with a high incidence and mortality rate. THZ2, a small inhibitor targeted CDK7, could inhibit multiple human tumor growths including small cell lung cancer, triple-negative breast cancer, ovarian cancer. However, the effect of THZ2 on inflammation, especially on colitis-associated colorectal cancer, is still unknown. In this study, we assessed the anti-inflammatory and anti-tumor effect of THZ2 in the mouse models of dextran sulfate sodium (DSS)-induced acute colitis and azoxymethane (AOM)/DSS-induced colitis-associated colorectal cancer. We found that THZ2 ameliorated inflammatory symptoms, including bleeding and diarrhea, in mouse models of DSS-induced acute colitis and AOM/DSS-induced colorectal cancer. The results of Western blot and immunohistochemistry showed that THZ2 rescued the up-regulated expression of COX2, IL-6, β-catenin, and snail in the mouse models. Moreover, THZ2 inhibits the development of colorectal cancer in the mouse model of AOM/DSS-induced colitis-associated colorectal cancer. Generally, THZ2 not only can inhibit DSS-induced colitis, but also can hinder AOM/DSS-induced colorectal cancer.

1,25(OH)2D3 supplementation alleviates gut–vascular barrier disruption via inhibition of S100B/ADAM10 pathway

ABSTRACT Gut–vascular barrier (GVB) is the second barrier in mucosa to control systemic dissemination of gut bacteria. Severe burns induce enteroglial cells to produce S100B and endothelial cells to generate ADAM10 and cause vitamin D3 insufficiency/deficiency and GVB disruption. It is not clear whether vitamin D3 supplementation attenuates GVB damage via regulation of S100B/ADAM10 pathway. Here, GVB disruption was induced by 30% of total body surface area scalds. Rats were treated with 1,25(OH)2D3 (0.05, 0.5 or 5 μg/kg) or S100B monoclonal antibody (S100BmAb, 10 μg/kg) or GI254023X (ADAM10 inhibitor, 100 mg/kg). Rat enteric glial cell-line CRL2690 and rat intestinal microvascular endothelial cells (RIMECs) were treated with S100B (5 μM) or plus 1,25(OH)2D3 (0.05, 0.5 or 5 μM) or GI254023X (5 μM). S100B, TNF-α, 25(OH)D3 and 1,25(OH)2D3 in serum and gut mucosa were determined by enzyme-linked immunosorbent assay. The endothelial permeability was measured using FITC-dextran 70 kDa. ADAM10 and β-catenin expression was assayed by Western blot. The results showed that 1,25(OH)2D3 and 25(OH)D3 concentration in serum reduced whereas TNF-α and S100B in serum and gut mucosa increased in burned rats. S100BmAb, GI254023X and 1,25(OH)2D3 treatment lowered burns-increased GVB permeability. 1,25(OH)2D3 also decreased S100B concentration in serum and gut mucosa. 1,25(OH)2D3 inhibited S100B release from TNF-α-treated CRL2690 and raised β-catenin while decreasing ADAM10 protein in S100B-treated RIMECs. 1,25(OH)2D3 and GI254023X also decreased the endothelial permeability of S100B-treated RIMECs. Collectively, these findings provide evidence that severe burns lower serum 25(OH)D3 and 1,25(OH)2D3 concentration. 1,25(OH)2D3 supplementation alleviates burns-elicited GVB disruption via inhibition of S100B/ADAM10 signaling.

L-arginine mitigates bleomycin-induced pulmonary fibrosis in rats through regulation of HO-1/PPAR-γ/β-catenin axis

Pulmonary fibrosis is a chronic and progressively deteriorating lung condition that can be replicated in laboratory animals by administering bleomycin, a chemotherapeutic antibiotic known for its lung fibrosis-inducing side effects. L-arginine, a semi-essential amino acid, is recognized for its diverse biological functions, including its potential to counteract fibrosis. This study aimed to evaluate the antifibrotic properties of L-arginine on bleomycin-induced pulmonary fibrosis in rats. The administration of a single intratracheal dose of bleomycin resulted in visible and microscopic damage to lung tissues, an uptick in oxidative stress markers, and an elevation in inflammatory, apoptotic, and fibrotic indicators. A seven-day treatment with L-arginine post-bleomycin exposure markedly improved the gross and histological architecture of the lungs, prevented the rise of malondialdehyde and carbonyl content, and enhanced total antioxidant capacity alongside the activities of antioxidant enzymes. Also, L-arginine attenuated the expression of the pro-fibrotic factors, transforming growth factor-β and lactate dehydrogenase in bronchoalveolar lavage fluid. In the lung tissue, L-arginine reduced collagen deposition, hydroxyproline concentration, and mucus production, along with decreasing expression of α-smooth muscle actin, tumor necrosis factor-α, caspase-3, matrix metalloproteinase-9, and β-catenin. Moreover, it boosted levels of nitric oxide and upregulated the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ), heme oxygenase-1 (HO-1), and E-cadherin and downregulating the expression of β-catenin. These findings suggest that L-arginine has preventive activities against bleomycin-induced pulmonary fibrosis. This effect can be attributed to the increased production of nitric oxide, which modulates the HO-1/PPAR-γ/β-catenin axis.

Clonal analysis of metachronous double biliary tract cancers.

The molecular mechanisms underpinning the development of metachronous tumors in the remnant bile duct following surgical resection of primary biliary tract carcinomas (BTCs) are unknown. This study aimed to elucidate these mechanisms by evaluating the clinicopathologic features of BTCs, the alterations to 31 BTC-related genes on targeted sequencing, and the aberrant expression of p53, p16, SMAD4, ARID1A and β-catenin on immunohistochemistry. Twelve consecutive patients who underwent resection of metachronous BTCs following primary BTC resection with negative bile duct margins were enrolled. Among the 12 metachronous tumors, six exhibited anterograde growth in the lower portion and six exhibited retrograde growth in the upper portion of the biliary tree. Surgical resection of metachronous BTCs resulted in recurrence-free survival in seven, local recurrence in five, and death in two patients. Nine achieved 5-year overall survival after primary surgery. Molecular analyses revealed that recurrently altered genes were: TP53, SMAD4, CDKN2A, ELF3, ARID1A, GNAS, NF1, STK11, RNF43, KMT2D and ERBB3. Each of these was altered in at least three cases. A comparison of the molecular features between 12 paired primary and metachronous BTCs indicated that 10 (83%) metachronous tumors developed in clonal association with corresponding primary tumors either successionally or phylogenically. The remaining two (17%) developed distinctly. The successional tumors consisted of direct or evolved primary tumor clones that spread along the bile duct. The phylogenic tumors consisted of genetically unstable clones and conferred a poor prognosis. Metachronous tumors distinct from their primaries harbored fewer mutations than successional and phylogenic tumors. In conclusion, over 80% of metachronous BTCs that develop following primary BTC resection are probably molecularly associated with their primaries in either a successional or a phylogenetic manner. Comparison between the molecular features of a metachronous tumor and those of a preceding tumor may provide effective therapeutic clues for the treatment of metachronous BTC. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Porcine transient receptor potential channel 1 (TRPC1) regulates muscle growth via the Wnt/β-catenin and Wnt/Ca2+ pathways

Transient receptor potential canonical (TRPC) channels allow the intracellular entry of Ca2+ and play important roles in several physio-pathological processes. In this study, we constructed transgenic mice expressing porcine TRPC1 (Tg-pTRPC1) to verify the effects of TRPC1 on skeletal muscle growth and elucidate the underlying mechanism. Porcine TRPC1 increased the muscle mass, fiber cross-sectional area, and exercise endurance of mice and accelerated muscle repair and regeneration. TRPC1 overexpression enhanced β-catenin expression and promoted myogenesis, which was partly reversed by inhibitors of β-catenin. TRPC1 facilitated the accumulation of intracellular Ca2+ and nuclear translocation of the NFATC2/NFATC2IP complex involved in the Wnt/Ca2+ pathway, promoting muscle growth. Paired related homeobox 1 (Prrx1) promoted the expression of TRPC1, NFATC2, and NFATC2IP that participate in the regulation of muscle growth. Taken together, our findings indicate that porcine TRPC1 promoted by Prrx1 could regulate muscle development through activating the canonical Wnt/β-catenin and non-canonical Wnt/Ca2+ pathways.

TP508 Promotes Bone Regeneration on Distraction Osteogenesis via the Activation of Wnt/β-catenin Signaling Pathway.

TP508 is a thrombin peptide that participates in the inflammatory response and wound healing. Its role in the molecular mechanism of distraction osteogenesis remains unclear. This study established a tibia distraction osteogenesis (DO) model in rats and investigated the role and mechanism of TP508 in bone regeneration during DO. Micro-computed tomography (Micro-CT) and hematoxylin-eosin (HE) staining were used to track osteogenesis. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to measure the expression of osteoblast-related factors, Wnt/β- catenin signaling-related proteins and genes. Immunohistochemistry was used to measure the expression of β-catenin in the cytoplasm and nucleus. TP508 accelerated bone regeneration increased the expression of the osteoblast-related factors Alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN). After the Wnt signaling was inhibited by LGK974, the expression of osteoblast-related factors was downregulated, leading to a decrease in bone regeneration ability. More importantly, TP508 upregulated β-catenin and its target CYCLIN-D1 and could reverse the decreased osteogenic ability caused by LGK974. In conclusion, TP508 promotes bone regeneration in DO by activating the Wnt/β- catenin signaling pathway.

Echinacoside ameliorates hepatic fibrosis and tumor invasion in rats with thioacetamide-induced hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) affects approximately 800,000 individuals globally each year. Despite advancements in HCC treatments, there is still a pressing need to identify new drugs that can combat resistance. One potential option is echinacoside, a natural caffeic acid glycoside with antioxidant, anti-inflammatory, antidepressant, and antidiabetic properties. Therefore, we aimed to investigate the ability of echinacoside to exhibit antitumor activity against HCC in rats through ameliorating hepatic fibrosis and tumor invasion. Rats were given thioacetamide to induce HCC, and some were given 30 mg/kg of echinacoside twice a week for 16 weeks. The liver impairment was assessed by measuring serum α-fetoprotein (AFP) and examining liver sections stained with Masson trichrome or anti-transforming growth factor (TGF)-β1 antibodies. The hepatic expression of mRNA and protein levels of TGF-β1, β-catenin, SMAD4, matrix metalloproteinase-9 (MMP9), phosphoinositide 3-kinases (PI3K), mammalian target of rapamycin (mTOR), connective tissue growth factor 2 (CCN2), E-Cadherin, platelets derived growth factor (PDGF)-B and fascin were also analyzed. Echinacoside improved the survival rate of rats by decreasing serum AFP and the number of hepatic nodules. Examination of micro-images indicated that echinacoside can reduce fibrosis. It also significantly decreased the expression of TGF-β1, β-catenin, SMAD4, MMP9, PI3K, mTOR, CCN2, PDGF-B, and fascin while enhancing the expression of E-Cadherin. In conclusion, echinacoside exhibits a protective effect against HCC by increasing survival rates and decreasing tumor growth. It also acts as an inhibitor of the hepatic tissue fibrosis pathway by reducing the expression of TGF-β1, β-catenin, SMAD4, PI3K, CCN2, PDGF-B and mTOR. Additionally, it prevents tumor invasion by suppressing MMP9 and fascin, and increasing the expression of E-Cadherin.