β-catenin inhibitors in cancer therapeutics: intricacies and way forward

Wnt signaling in cancer: from biomarkers to targeted therapies and clinical translation

The Wnt signaling pathway plays a crucial role in development and tissue homeostasis, regulating key cellular processes such as proliferation, differentiation, and apoptosis. However, its abnormal activation is strongly associated with tumorigenesis, metastasis, and resistance to therapy, making it a vital target for cancer treatment. This review provides a comprehensive insight into the role of Wnt signaling in cancer, examining its normal physiological functions, dysregulation in malignancies, and therapeutic potential. We emphasize the importance of predicting Wnt signaling sensitivity and identify key biomarkers across various cancer types. Additionally, we address the challenges and future prospects of Wnt-targeted therapies, including biomarker discovery, advancements in emerging technologies, and their application in clinical practice.

Mechanism of β-Catenin in Pulmonary Fibrosis Following SARS-CoV-2 Infection

Pulmonary fibrosis due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is the leading cause of death in patients with COVID-19. β-catenin, a key molecule in the Wnt/β-catenin signaling pathway, has been shown to be involved in the development of pulmonary fibrosis (e.g., idiopathic pulmonary fibrosis, silicosis). In this study, we developed a SARS-CoV-2-infected A549-hACE2 cell model to evaluate the efficacy of the A549-hACE2 monoclonal cell line against SARS-CoV-2 infection. The A549-hACE2 cells were then subjected to either knockdown or overexpression of the effector β-catenin, and the modified cells were subsequently infected with SARS-CoV-2. Additionally, we employed transcriptomics and raw letter analysis approaches to investigate other potential effects of β-catenin on SARS-CoV-2 infection. We successfully established a model of cellular fibrosis induced by SARS-CoV-2 infection in lung-derived cells. This model can be utilized to investigate the molecular biological mechanisms and cellular signaling pathways associated with virus-induced lung fibrosis. The results of our mechanistic studies indicate that β-catenin plays a significant role in lung fibrosis resulting from SARS-CoV-2 infection. Furthermore, the inhibition of β-catenin mitigated the accumulation of mesenchymal stroma in A549-hACE2 cells. Additionally, β-catenin knockdown was found to facilitate multi-pathway crosstalk following SARS-CoV-2 infection. The fact that β-catenin overexpression did not exacerbate cellular fibrosis may be attributed to the activation of PPP2R2B.

The role of various collagen types in tumor biology: a review

Collagen comprises approximately 30% of the body's protein content and is essential for maintaining the structural integrity, support, and strength of the skin, muscles, bones, and connective tissues. Recent research has further elucidated its role in various aspects of tumor biology, including tumorigenesis, invasion, migration, drug resistance, and recurrence. Furthermore, collagen is involved in prognostic assessments, the evaluation of therapeutic efficacy, immunoregulation, and the identification of potential treatment targets in oncology. This review examines a range of tumor types, including lung, gastric, breast, melanoma, and colorectal cancers, among others. Our objective is to differentiate these tumors based on the specific types of collagen present and to analyze the roles of various collagen types in tumor development, progression, prognosis, and their potential as therapeutic targets.

PMEPA1 Binds NEDD4L to Inhibit the Malignant Progression of Multiple Myeloma by Inactivating Wnt/β-Catenin Signaling

Multiple myeloma (MM) is an incurable hematological malignancy with increasing prevalence. Prostate transmembrane androgen inducible protein 1 (PMEPA1) is positively associated with overall survival in MM patients, but the exact functions and mechanisms of PMEPA1 in MM have yet to be elucidated. PMEPA1 and neural precursor cell-expressed developmentally downregulated gene 4L (NEDD4L) levels in MM cells were examined. In RPMI-8226 cells with PMEPA1 overexpression or/and NEDD4L knockdown, cell proliferation, cycle distribution and apoptosis were evaluated with the application of CCK-8, EDU staining and flow cytometry. The BioGrid website and HDOCK SERVER were applied for predicting the binding between PMEPA1 and NEDD4L, which was checked by co-immunoprecipitation. Besides, the levels of proteins associated with proliferation (Ki67 and PCNA), apoptosis (Bcl-2, Bax and cleaved caspase3) and Wnt/β-catenin signaling (β-catenin, c-Myc and cyclin D1) was detected with immunoblotting. Finally, LiCl, an activator of Wnt/β-catenin pathway, was employed to treat RPMI-8226 cells to analyze the proliferation, cycle distribution and apoptosis of MM cells. As a result, PMEPA1 and NEDD4L were expressed at low levels in MM cells. PMEPA1 upregulation repressed proliferation induced cycle arrest and facilitated apoptosis of MM cells. Moreover, PMEPA1 bound to NEDD4L and upregulated NEDD4L expression in RPMI-8226 cells. Functionally, NEDD4L knockdown attenuated the influences of PMEPA1 overexpression on the proliferation, cycle distribution and apoptosis of RPMI-8226 cells. Additionally, PMEPA1 notably downregulated β-catenin, c-Myc and cyclin D1 expression in RPMI-8226 cells, which was abrogated by NEDD4L silencing. Further adding LiCl in RPMI-8226 cells led to the enhanced malignant biological behaviors. Collectively, PMEPA1 damaged MM progression through binding NEDD4L to inactivate Wnt/β-catenin signaling, which may be helpful to develop promising targets for MM treatment.

AURKC Promotes Clear Cell Renal Cell Carcinoma Proliferation Through Upregulation of ERp57

In recent years, aurora kinase C (AURKC) has emerged as a potential therapeutic target for cancer, having been found to induce proliferation in a variety of cancers. However, at present, its precise mechanism remains unclear. In this study, the specific role of AURKC in renal clear cell carcinoma and its mechanism was investigated. The protein expression levels of AURKC were evaluated in clear cell carcinoma and adjacent normal tissues, followed by prognostic analysis. Subsequently, cell models with knocked-down and overexpressed AURKC were constructed for in vitro cell experiments, and tumor-bearing mouse models were constructed to confirm the specific role of AURKC in vivo. AURKC was found to be highly expressed in ccRCC, which was associated with poor prognosis. In the in vitro experiments, the expression levels of CyclinD1 and proliferating cell nuclear antigen (PCNA) proteins were downregulated after AURKC knockdown, and the cell proliferation ability was found to decrease significantly. After AURKC overexpression, the levels of ERp57 protein expression increased significantly, also significantly enhancing the cell proliferation ability. In addition, AURKC was found to interact with ERp57 and exhibited a colocalization relationship. In the in vivo experiments, AURKC downregulation significantly inhibited the expression of ERp57 protein and blocked the growth of tumor tissue in tumor-bearing mice. These results suggest that the abnormal expression of AURKC in ccRCC enhances the expression of ERp57 protein, thereby promoting the proliferation of clear cell renal cell carcinoma. Thus, AURKC shows potential as a target for the treatment of ccRCC.

CCDC34 maintains stemness phenotype through β-catenin-mediated autophagy and promotes EGFR-TKI resistance in lung adenocarcinoma

Despite recent advances in treatment strategy, lung cancer remains the leading cause of cancer-related mortality worldwide, and it is a serious threat to human health. Lung adenocarcinoma (LUAD) is the most common histological type of lung cancer, and approximately 40-50% of patients with LUAD in Asian populations have epidermal growth factor receptor (EGFR) mutations. The use of EGFR tyrosine kinase inhibitors (EGFR-TKIs) has revolutionarily improved the prognosis of patients with EGFR-mutated LUAD. However, acquired drug resistance is the main cause of treatment failure. Therefore, new therapeutic strategies are necessary to address the resistance to EGFR-TKIs in patients with LUAD. Cancer stemness-related factors lead to multiple-drug resistance in cancer treatment, including EGFR-TKI resistance. Coiled-coil domain-containing 34 (CCDC34) serves as an oncogene in several types of cancer. However, the role and molecular mechanism of CCDC34 in the malignant progression of LUAD have not been reported to date. In the present study, we found that CCDC34 may be associated with LUAD stemness through weighted gene co-expression network analysis (WGCNA). Furthermore, we demonstrated that CCDC34 promoted LUAD stemness properties through β-catenin-mediated regulation of ATG5-induced autophagy, which was conducive to acquired EGFR-TKI resistance in LUAD in vitro and in vivo. Knockdown CCDC34 can synergistically inhibit tumor growth when combined with EGFR-TKIs. This study reveals a positive association between CCDC34 and the stemness phenotype of LUAD, providing new insights into overcoming EGFR-TKI resistance in LUAD by inhibiting CCDC34 expression.

TOP2A Promotes Proliferation, Migration, and Inflammatory Response in M5-Treated Keratinocytes by Binding CTBP1 to Activate Wnt/β-Catenin Signaling

Psoriasis is a chronic cutaneous disease, affecting a significant portion of the global population. Topoisomerase II alpha (TOP2A) is upregulated in psoriasis samples, but the precise molecular mechanism remains unclear. We aimed to clarify the biological contribution of TOP2A in psoriasis progression. An in vitro psoriasis model was established on M5-induced keratinocytes (HaCaT cells) to simulate the psoriasis-like alterations. Following TOP2A knockdown without or with c terminal binding protein 1 (CTBP1) overexpression, CCK-8 and EDU staining were employed to analyze the viability and proliferation of HaCaT cells under M5 conditions. The capacities of HaCaT cell migration and invasion were examined with wound healing- and transwell assays. RT-qPCR and immunoblotting were adopted for evaluation of the inflammation and differentiation of M5-stimualted HaCaT cells. Additionally, the binding between TOP2A and CTBP1 was predicated using bioinformatics tools and detected by Co-IP. Finally, the expression of proteins in Wnt/β-catenin signaling was analyzed with the application of immunoblotting. Results suggested that TOP2A was upregulated in psoriasis skin lesions and M5-induced HaCaT cells. Interference with TOP2A attenuated the proliferation, migration, invasion, and inflammatory response in M5-treated HaCaT cells. In particular, TOP2A bound to CTBP1 and upregulated CTBP1 expression in HaCaT cells. Remarkably, CTBP1 upregulation blocked the impacts of TOP2A depletion on the biological behaviors of M5-treated HaCaT cells. Besides, TOP2A deficiency upregulated DKK1 expression as well as downregulated Wnt1, β-catenin, and c-Myc expression in HaCaT cells exposed to M5, which was restored by further CTBP1 overexpression. In summary, TOP2A binds CTBP1 to activate Wnt/β-catenin signaling, thereby promoting the progression of psoriasis.

CD73 restrains mutant β-catenin oncogenic activity in endometrial carcinomas

Missense mutations in exon 3 of CTNNB1, the gene encoding β-catenin, are associated with poor outcomes in endometrial carcinomas (EC). Clinically, CTNNB1 mutation status has been difficult to use as a predictive biomarker as β-catenin oncogenic activity is modified by other factors, and these determinants are unknown. Here we reveal that CD73 restrains the oncogenic activity of exon 3 β-catenin mutants, and its loss associates with recurrence. Using 7 patient-specific mutants, with genetic deletion or ectopic expression of CD73, we show that CD73 loss increases β-catenin-TCF/LEF transcriptional activity. In cells lacking CD73, membrane levels of mutant β-catenin decreased which corresponded with increased levels of nuclear and chromatin-bound mutant β-catenin. These results suggest CD73 sequesters mutant β-catenin to the membrane to limit its oncogenic activity. Adenosine A1 receptor deletion phenocopied increased β-catenin-TCF/LEF activity seen with NT5E deletion, suggesting that the effect of CD73 loss on mutant β-catenin is mediated via attenuation of adenosine receptor signaling. RNA-seq analyses revealed that NT5E deletion alone drives pro-tumor Wnt/β-catenin gene expression and, with CD73 loss, β-catenin mutants dysregulate zinc-finger and non-coding RNA gene expression. We identify CD73 as a novel regulator of oncogenic β-catenin and help explain variability in patient outcomes in CTNNB1 mutant EC.

WNT7B promotes cancer progression via WNT/β-catenin signaling pathway and predicts a poor prognosis in oral squamous cell carcinoma

BACKGROUND

WNT7B is a glycoprotein that plays a crucial role in tumorigenesis. This study aimed to investigate the role of WNT7B in oral squamous cell carcinoma (OSCC).

METHODS

Bioinformatic databases, immunohistochemistry, a real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay were used to detect WNT7B expression in OSCC. The clinical and prognostic importance of WNT7B expression was evaluated. WNT7B expression was examined in oral leukoplakia and carcinoma induced by 4-nitroquinoline 1-oxide in mice. Loss- and gain-of-function analyses were performed to elucidate the role of WNT7B in OSCC cells. Subcutaneous tumor model was established to observe the effects of WNT7B on tumor growth. Co-Immunoprecipitation was used to explore the Frizzled receptors that WNT7B may bind to.

RESULTS

WNT7B upregulated in OSCC and associated with lymph node metastasis, perineural invasion, and an unfavorable prognosis in patients with OSCC. A gradual increased in WNT7B expression during the malignant progression of OSCC. WNT7B promoted cell proliferation, migration, invasion, while silencing WNT7B abolished these effects. Knocking down the expression of WNT7B inhibits tumor growth in vivo. WNT7B functions by binding to the Frizzled 7 receptor and facilitates the nuclear translocation of β-catenin.

CONCLUSIONS

WNT7B contributes to the progression of OSCC by modulating the WNT/β-catenin signaling pathway. These findings highlight the potential of WNT7B as a novel prognostic biomarker and promising therapeutic target for OSCC.

Biological effect of U(VI) exposure on lung epithelial BEAS-2B cells

In this study, the biological effects of U(VI) exposure on lung epithelial cells were investigated by MTT assay, immunofluorescence, flow cytometry, and Western blotting. U(VI)-induced stress triggers oxidative stress in cells, activates MAPK signaling pathways, and promotes inflammation. Additionally, U(VI) causes damage to the cell membrane structure and severe DNA injury, impacting the accuracy of transcription and translation. The results demonstrate that U(VI) exposure significantly inhibits cell proliferation and migration. This is attributed to the disruption of the PI3K/AKT/GSK-3β/β-catenin signaling pathway and the reduction in CyclinD1 expression, leading to a delayed cell cycle, decreased growth rate, mitochondrial damage, and reduced energy metabolism. This study provides a comprehensive understanding of the molecular mechanisms underlying uranium-induced cellular toxicity in lung epithelial cells.

The significant others of aurora kinase a in cancer: combination is the key

AURKA is predominantly famous as an essential mitotic kinase. Recent findings have also established its critical role in a plethora of other biological processes including ciliogenesis, mitochondrial dynamics, neuronal outgrowth, DNA replication and cell cycle progression. AURKA overexpression in numerous cancers is strongly associated with poor prognosis and survival. Still no AURKA-targeted drug has been approved yet, partially because of the associated collateral toxicity and partly due to its limited efficacy as a single agent in a wide range of tumors. Mechanistically, AURKA overexpression allows it to phosphorylate numerous pathological substrates promoting highly aggressive oncogenic phenotypes. Our review examines the most recent advances in AURKA regulation and focuses on 33 such direct cancer-specific targets of AURKA and their associated oncogenic signaling cascades. One of the common themes that emerge is that AURKA is often involved in a feedback loop with its substrates, which could be the decisive factor causing its sustained upregulation and hyperactivation in cancer cells, an Achilles heel not exploited before. This dynamic interplay between AURKA and its substrates offers potential opportunities for targeted therapeutic interventions. By targeting these substrates, it may be possible to disrupt this feedback loop to effectively reverse AURKA levels, thereby providing a promising avenue for developing safer AURKA-targeted therapeutics. Additionally, exploring the synergistic effects of AURKA inhibition with its other oncogenic and/or tumor-suppressor targets could provide further opportunities for developing effective combination therapies against AURKA-driven cancers, thereby maximizing its potential as a critical drug target.

Evaluation of Efficiency of Liposome-Entrapped Iridium(III) Complexes Inhibiting Tumor Growth In Vitro and In Vivo

In this paper, three new iridium(III) complexes: [Ir(piq)2(DFIPP)]PF6 (piq = deprotonated 1-phenylisoquinoline, DFIPP = 3,4-difluoro-2-(1H-imidazo[4,5-f][1,10]phenenthrolin-2-yl)phenol, 3a), [Ir(bzq)2(DFIPP)]PF6 (bzq = deprotonated benzo[h]quinoline, 3b), and [Ir(ppy)2(DFIPP)]PF6 (ppy = deprotonated 1-phenylpyridine, 3c), were synthesized and characterized. The complexes were found to be nontoxic to tumor cells via 3-(4,5-dimethylthiazole-2-yl)-diphenyltetrazolium bromide (MTT) assay. Surprisingly, its liposome-entrapped complexes 3alip, 3blip, and 3clip on B16 cells showed strong cytotoxicity (IC50 = 13.6 ± 2.8, 9.6 ± 1.1, and 18.9 ± 2.1 μM). Entry of 3alip, 3blip, and 3clip into B16 cells decreases mitochondrial membrane potential, regulates Bcl-2 family proteins, releases cytochrome c, triggers caspase family cascade reaction, and induces apoptosis. In addition, we also found that 3alip, 3blip, and 3clip triggered ferroptosis and autophagy. In vivo studies demonstrated that 3blip inhibited melanoma growth in C57 mice with a high inhibitory rate of 83.95%, and no organic damage was found in C57 mice.

Protein-Based Predictive Biomarkers to Personalize Neoadjuvant Therapy for Bladder Cancer-A Systematic Review of the Current Status

The clinical outcome of patients with muscle-invasive bladder cancer (MIBC) is poor despite the approval of neoadjuvant chemotherapy or immunotherapy to improve overall survival after cystectomy. MIBC subtypes, immune, transcriptome, metabolomic signatures, and mutation burden have the potential to predict treatment response but none have been incorporated into clinical practice, as tumor heterogeneity and lineage plasticity influence their efficacy. Using the PRISMA statement, we conducted a systematic review of the literature, involving 135 studies published within the last five years, to identify studies reporting on the prognostic value of protein-based biomarkers for response to neoadjuvant therapy in patients with MIBC. The studies were grouped based on biomarkers related to molecular subtypes, cancer stem cell, actin-cytoskeleton, epithelial-mesenchymal transition, apoptosis, and tumor-infiltrating immune cells. These studies show the potential of protein-based biomarkers, especially in the spatial context, to reduce the influence of tumor heterogeneity on a biomarker's prognostic capability. Nevertheless, currently, there is little consensus on the methodology, reagents, and the scoring systems to allow reliable assessment of the biomarkers of interest. Furthermore, the small sample size of several studies necessitates the validation of potential prognostic biomarkers in larger multicenter cohorts before their use for individualizing neoadjuvant therapy regimens for patients with MIBC.

SUMO3 inhibition by butyric acid suppresses cell viability and glycolysis and promotes gemcitabine antitumor activity in pancreatic cancer

BACKGROUND

Excavation of key molecules can help identify therapeutic targets and improve the prognosis of pancreatic cancer. This study evaluated the roles of SUMO3 in cell viability, glycolysis, gemcitabine (GEM) sensitivity, and the antitumor activity of butyric acid (BA) in pancreatic cancer.

METHODS

The mRNA and protein levels of SUMO3 were detected by qRT-PCR, Western blot, and immunohistochemical assay. SUMO3 was silenced or overexpressed in pancreatic cancer cells with or without Wnt/β-catenin pathway inhibitor, glycolysis inhibitor, GEM, or BA treatment. Cell viability was measured using the Cell Counting Kit-8 assay. Glycolysis was measured by determining the extracellular acidification rate, ATP level, and lactate content. Apoptosis was measured by flow cytometry, and TUNEL staining was used to examine in vitro and in vivo sensitivity to GEM chemotherapy. Luciferase reporter and chromatin immunoprecipitation assays were conducted to detect the binding of the SUMO3 promoter and NF-κB p65.

RESULTS

SUMO3 was increased and associated with poor survival in pancreatic cancer. SUMO3 knockdown decreased cell viability and glycolysis in vitro and inhibited tumor growth in vivo. SUMO3 overexpression increased cell viability and glycolysis in vitro through the β-catenin pathway. SUMO3 knockdown increased GEM sensitivity, whereas SUMO3 overexpression decreased GEM sensitivity and inhibited the antitumor activity of BA. BA promoted histone acetylation and p-IκBα expression to inhibit NF-κB p65-mediated SUMO3 transcription.

CONCLUSION

SUMO3 acted as an active molecule in cell survival and growth by enhancing glycolysis in response to either GEM or BA. The mechanism was related to the constitutive IκBα/NF-κB/SUMO3/β-catenin signaling pathway.

P4HA3 promotes head and neck squamous cell carcinoma progression via the WNT/β-catenin signaling pathway

Here, we explored the role of Prolyl 4-Hydroxylase Subunit Alpha 3 (P4HA3), the most recently identified member of the prolyl-4-hydroxylase (P4H) family, in head and neck squamous cell carcinoma (HNSCC) progression. P4HA3 is upregulated during cancer progression; however, its specific role in HNSCC progression remains elusive. Thus, this study aimed to elucidate the regulatory function of P4HA3 in HNSCC development and progression and to describe the underlying mechanisms. Initially, we analyzed the correlation between the expression of P4HA3 and the WNT pathway genes and clinicopathologic features in HNSCC based on microarray data from The Cancer Genome Atlas (TCGA). Next, we used Gene Oncology (GO) functional data to describe several potentially associated pathways in HNSCC. Then, we knocked down P4HA3 in SCC15 and SCC25 cells, two classic HNSCC cell lines, and assessed the resulting changes using RT-qPCR. Furthermore, we used Western blot to evaluate the regulatory role of P4HA3 in the epithelial-to-mesenchymal transition (EMT) and the WNT/β-catenin signaling pathway. To explore the effect of P4HA3 knockdown on tumor progression, in vivo experiments were conducted using a murine model. Immunohistochemistry assays were then employed to identify proteins associated with EMT and the WNT/β-catenin signaling pathway in tumor tissues. Upregulated P4HA3 in HNSCC patient tumor tissues was positively correlated with poor prognosis. Notably, P4HA3 knockdown significantly inhibited the proliferative and invasive abilities of HNSCC. The levels of genes and proteins associated with EMT and the WNT/β-catenin signaling pathway were also markedly reduced by P4HA3 knockdown. Importantly, the in vivo experiments demonstrated that P4HA3 can promote subcutaneous tumorigenesis in nude mice and knockdown of P4HA3 induce a significant ihibitation of EMT and WNT/β-catenin pathway detected by immunohistochemistry assay in tumor tissues. In summary, we demonstrated that P4HA3 is a promising diagnostic and therapeutic biomarker for HNSCC. As an oncogene, P4HA3 increases HNSCC proliferation by inducing the EMT and activating the WNT/β-catenin signaling pathway.

Canonical WNT/β-catenin signaling upregulates aerobic glycolysis in diverse cancer types

Despite many efforts, a comprehensive understanding and clarification of the intricate connections within cancer cell metabolism remain elusive. This might pertain to intracellular dynamics and the complex interplay between cancer cells, and cells with the tumor stroma. Almost a century ago, Otto Warburg found that cancer cells exhibit a glycolytic phenotype, which continues to be a subject of thorough investigation. Past and ongoing investigations have demonstrated intricate mechanisms by which tumors modulate their functionality by utilizing extracellular glucose as a substrate, thereby sustaining the essential proliferation of cancer cells. This concept of "aerobic glycolysis," where cancer cells (even in the presence of enough oxygen) metabolize glucose to produce lactate plays a critical role in cancer progression and is regulated by various signaling pathways. Recent research has revealed that the canonical wingless-related integrated site (WNT) pathway promotes aerobic glycolysis, directly and indirectly, thereby influencing cancer development and progression. The present review seeks to gather knowledge about how the WNT/β-catenin pathway influences aerobic glycolysis, referring to relevant studies in different types of cancer. Furthermore, we propose the concept of impeding the glycolytic phenotype of tumors by employing specific inhibitors that target WNT/β-catenin signaling.

Covalent Degrader of the Oncogenic Transcription Factor β-Catenin

β-catenin (CTNNB1) is an oncogenic transcription factor that is important in cell-cell adhesion and transcription of cell proliferation and survival genes that drive the pathogenesis of many different types of cancers. However, direct pharmacological targeting of CTNNB1 has remained challenging. Here, we have performed a screen with a library of cysteine-reactive covalent ligands to identify the monovalent degrader EN83 that depletes CTNNB1 in a ubiquitin-proteasome-dependent manner. We show that EN83 directly and covalently targets CTNNB1 three cysteines C466, C520, and C619, leading to destabilization and degradation of CTNNB1. Through structural optimization, we generate a highly potent and relatively selective destabilizing degrader that acts through the targeting of only C619 on CTNNB1. Our results show that chemoproteomic approaches can be used to covalently target and degrade challenging transcription factors like CTNNB1 through destabilization-mediated degradation.

Daurisoline inhibits proliferation, induces apoptosis, and enhances TRAIL sensitivity of breast cancer cells by upregulating DR5

Daurisoline (DS) is an isoquinoline alkaloid that exerts anticancer activities in various cancer cells. However, the underlying mechanisms through which DS affects the survival of breast cancer cells remain poorly understood. Therefore, the present study was undertaken to investigate the potential anticancer effect of DS on breast cancer cells and reveal the mechanism underlying the enhanced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis by DS. Cell counting kit-8 (CCK-8) and 5-ethynyl-2-deoxyuridine (EdU) assay were used to evaluate the ability of cell proliferation. Flow cytometry was selected to examine the cell cycle distribution. TUNEL assay was used to detect the cell apoptosis. The protein expression was measured by Western blot analysis. DS was found to reduce the cell viability and suppress the proliferation of MCF-7 and MDA-MB-231 cells by causing G1 phase cell cycle arrest. DS could trigger apoptosis by promoting the cleavage of caspase-8 and PARP. The phosphorylation of ERK, JNK, and p38MAPK was upregulated clearly following DS treatment. Notably, SP600125 (JNK inhibitor) pretreatment significantly abrogated DS-induced PARP cleavage. DS inactivated Akt/mTOR and Wnt/β-catenin signaling pathway and upregulated the expression of ER stress-related proteins. Additionally, DS amplified TRAIL-caused viability reduction and apoptosis in breast cancer cells. Mechanismly, DS upregulated the protein level of DR4 and DR5, and knockdown of DR5 attenuated the cotreatment-induced cleavage of PARP. Inhibition of JNK could block DS-induced upregulation of DR5. This study provides valuable insights into the mechanisms of DS inhibiting cell proliferation, triggering apoptosis, and enhancing TRAIL sensitivity of breast cancer cells.

Targeting triple negative breast cancer stem cells using nanocarriers

Breast cancer is a complex and heterogeneous disease, encompassing various subtypes characterized by distinct molecular features, clinical behaviors, and treatment responses. Categorization of subtypes is based on the presence or absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), leading to subtypes such as luminal A, luminal B, HER2-positive, and triple-negative breast cancer (TNBC). TNBC, comprising around 20% of all breast cancers, lacks expression of ER, PR, and HER2 receptors, rendering it unresponsive to targeted therapies and presenting significant challenges in treatment. TNBC is associated with aggressive behavior, high rates of recurrence, and resistance to chemotherapy. Tumor initiation, progression, and treatment resistance in TNBC are attributed to breast cancer stem cells (BCSCs), which possess self-renewal, differentiation, and tumorigenic potential. Surface markers, self-renewal pathways (Notch, Wnt, Hedgehog signaling), apoptotic protein (Bcl-2), angiogenesis inhibition (VEGF inhibitors), and immune modulation (cytokines, immune checkpoint inhibitors) are among the key targets discussed in this review. However, targeting the BCSC subpopulation in TNBC presents challenges, including off-target effects, low solubility, and bioavailability of anti-BCSC agents. Nanoparticle-based therapies offer a promising approach to target various molecular pathways and cellular processes implicated in survival of BSCS in TNBC. In this review, we explore various nanocarrier-based approaches for targeting BCSCs in TNBC, aiming to overcome these challenges and improve treatment outcomes for TNBC patients. These nanoparticle-based therapeutic strategies hold promise for addressing the therapeutic gap in TNBC treatment by delivering targeted therapies to BCSCs while minimizing systemic toxicity and enhancing treatment efficacy.

Discovery of New Anti-Cancer Agents against Patient-Derived Sorafenib-Resistant Papillary Thyroid Cancer

Thyroid cancer is the most well-known type of endocrine cancer that is easily treatable and can be completely cured in most cases. Nonetheless, anti-cancer drug-resistant metastasis or recurrence may occur and lead to the failure of cancer therapy, which eventually leads to the death of a patient with cancer. This study aimed to detect novel thyroid cancer target candidates based on validating and identifying one of many anti-cancer drug-resistant targets in patient-derived sorafenib-resistant papillary thyroid cancer (PTC). We focused on targeting the sarco/endoplasmic reticulum calcium ATPase (SERCA) in patient-derived sorafenib-resistant PTC cells compared with patient-derived sorafenib-sensitive PTC cells. We discovered novel SERCA inhibitors (candidates 33 and 36) by virtual screening. These candidates are novel SERCA inhibitors that lead to remarkable tumor shrinkage in a xenograft tumor model of sorafenib-resistant patient-derived PTC cells. These results are clinically valuable for the progression of novel combinatorial strategies that facultatively and efficiently target extremely malignant cancer cells, such as anti-cancer drug-resistant PTC cells.

Covalent Degrader of the Oncogenic Transcription Factor β-Catenin

β-catenin (CTNNB1) is an oncogenic transcription factor that is important in cell-cell adhesion and transcription of cell proliferation and survival genes that drives the pathogenesis of many different types of cancers. However, direct pharmacological targeting of CTNNB1 has remained challenging deeming this transcription factor as "undruggable." Here, we have performed a screen with a library of cysteine-reactive covalent ligands to identify a monovalent degrader EN83 that depletes CTNNB1 in a ubiquitin-proteasome-dependent manner. We show that EN83 directly and covalently targets CTNNB1 through targeting four distinct cysteines within the armadillo repeat domain-C439, C466, C520, and C619-leading to a destabilization of CTNNB1. Using covalent chemoproteomic approaches, we show that EN83 directly engages CTNNB1 in cells with a moderate degree of selectivity. We further demonstrate that direct covalent targeting of three of these four cysteines--C466, C520, and C619--in cells contributes to CTNNB1 degradation in cells. We also demonstrate that EN83 can be further optimized to yield more potent CTNNB1 binders and degraders. Our results show that chemoproteomic approaches can be used to covalently target and degrade challenging transcription factors like CTNNB1 through a destabilization-mediated degradation.

Modulating β-catenin/BCL9 interaction with cell-membrane-camouflaged carnosic acid to inhibit Wnt pathway and enhance tumor immune response

Introduction

Lung adenocarcinoma (LUAD) therapies are plagued by insufficient immune infiltration and suboptimal immune responses in patients, which are closely associated with the hyperactive Wnt/β-catenin pathway. Suppressing this signaling holds considerable promise as a potential tumor therapy for LUAD, but Wnt suppressor development is hindered by concerns regarding toxicity and adverse effects due to insufficient targeting of tumors.

Methods

We have synthesized a tumor-specific biomimetic Wnt pathway suppressor, namely CM-CA, by encapsulating carnosic acid within Lewis lung carcinoma (LLC) cell membranes. It possesses nano-size, allowing for a straightforward preparation process, and exhibits the ability to selectively target the Wnt/β-catenin pathway in lung adenocarcinoma cells. To evaluate its in vivo efficacy, we utilized the LLC Lewis homograft model, and further validated its mechanism of action through immunohistochemistry staining and transcriptome sequencing analyses.

Results

The findings from the animal experiments demonstrated that CM-CA effectively suppressed the Wnt/β-catenin signaling pathway and impeded cellular proliferation, leading to notable tumor growth inhibition in a biologically benign manner. Transcriptome sequencing analyses revealed that CM-CA promoted T cell infiltration and bolstered the immune response within tumor tissues.

Conclusion

The utilization of CM-CA presents a novel and auspicious approach to achieve tumor suppression and augment the therapeutic response rate in LUAD, while also offering a strategy for the development of Wnt/β-catenin inhibitors with biosafety profile.