WNT antagonists exhibit unique combinatorial antitumor activity with taxanes by potentiating mitotic cell death

Role of the Wnt signaling pathway in the complex microenvironment of breast cancer and prospects for therapeutic potential (Review)

The focus on breast cancer treatment has shifted from the cytotoxic effects of single drugs on tumor cells to multidimensional multi‑pathway synergistic intervention strategies targeting the tumor microenvironment (TME). The activation of the Wnt signaling pathway in the TME of breast cancer cells serves a key regulatory role in tissue homeostasis and is a key driver of the carcinogenic process. Modulating the crosstalk between the Wnt pathway and TME of breast cancer is key for understanding the biological behavior of breast cancer and advancing the development of novel antitumor drugs. The present review aimed to summarize the complex mechanisms of the Wnt signaling pathway in the breast cancer TME, interactions between the Wnt signaling pathway and components of the breast cancer TME and breast cancer‑associated genes, as well as the interactions between the Wnt signaling pathway and other signaling cascades at the molecular level. Furthermore, the present review aimed to highlight the unique advantages of the Wnt signaling pathway in the macro‑regulation of the TME and the current therapeutic strategies targeting the Wnt signaling pathway, their potential clinical value and future research directions in breast cancer treatment.

Targeted treatment for craniopharyngioma

INTRODUCTION

Craniopharyngioma is a rare solid-cystic tumor of the hypothalamopituitary region. Two distinct craniopharyngioma types (formerly subtypes), adamantinomatous and papillary, have been described. These tumors often manifest with neuroendocrine dysfunction, vision problems, hydrocephalus, and cognitive changes. Despite efforts to spare vital brain structures, conventional treatments such as surgery and radiation can exacerbate preceding deficits and contribute to permanent neurologic impairment. Recent studies have identified BRAF-V600E mutations in nearly all papillary craniopharyngiomas (PCP), and CTNNB1/Wnt pathway alterations in adamantinomatous craniopharyngiomas (ACP). These discoveries have advanced our understanding of craniopharyngioma pathogenesis and have opened opportunities for targeted biological treatments.

PURPOSE

The primary objective of this article is to review the current landscape of targeted treatments in papillary and adamantinomatous craniopharyngioma.

RESULTS

Treatment of PCP with BRAF/MEK inhibition has demonstrated durable tumor response in the adjuvant and neoadjuvant settings in multiple case studies and one phase II clinical trial. Although treatment advances are more limited for ACP, CTNNB1/Wnt pathway inhibitors showed promising results in pre-clinical studies and are under continued investigation.

CONCLUSION

The efficacy of BRAF/MEK inhibition in PCP supports the use of targeted therapy in patients with newly diagnosed PCP. The optimal targeted treatment combinations and their timing, duration, long-term effects, and sequencing with traditional therapeutic modalities have not been established and warrant further study. Targeted therapies represent a significant advancement in the field of oncology, and craniopharyngiomas are viable candidates for these approaches pending further research.

Unraveling the Role of the Wnt Pathway in Hepatocellular Carcinoma: From Molecular Mechanisms to Therapeutic Implications

Hepatocellular carcinoma (HCC) is one of the deadliest malignant tumors in the world, and its incidence and mortality have increased year by year. HCC research has increasingly focused on understanding its pathogenesis and developing treatments.The Wnt signaling pathway, a complex and evolutionarily conserved signal transduction system, has been extensively studied in the genesis and treatment of several malignant tumors. Recent investigations suggest that the pathogenesis of HCC may be significantly influenced by dysregulated Wnt/β-catenin signaling. This article aimed to examine the pathway that controls Wnt signaling in HCC and its mechanisms. In addition, we highlighted the role of this pathway in HCC etiology and targeted treatment.

Regulatory effect of Wnt signaling on mitochondria in cancer: from mechanism to therapy

Cancer is one of the most significant public health challenges in the new millennium, and complex mechanisms are at work to contribute to its pathogenesis and progression. The Wnt signaling pathways, which are crucial conserved cascades involved in embryological development and tissue homeostasis, and mitochondria, the intracellular powerhouses responsible for energy production, calcium and iron homeostasis, as well as mitochondrial apoptosis in eukaryotic cells, have their own mechanisms regulating these pathological processes. In the past decade, accumulating evidence has indicated that Wnt signaling pathways directly regulate mitochondrial biogenesis and function under physiological and pathological conditions. In this review, we systemically summarize the current understanding of how Wnt signaling pathways, particularly the canonical Wnt cascade, regulate mitochondrial fission, respiration, metabolism, and mitochondrial-dependent apoptosis in cancer. In addition, we discuss recent advancements in the research of anticancer agents and related pharmacological mechanisms targeting the signaling transduction of canonical Wnt pathway and/or mitochondrial function. We believe that the combined use of pharmaceuticals targeting Wnt signaling and/or mitochondria with conventional therapies, immunotherapy and targeted therapy based on accurate molecular pathological diagnosis will undoubtedly be the future mainstream direction of personalized cancer treatment, which could benefit more cancer patients.

Wnt signaling pathways in biology and disease: mechanisms and therapeutic advances

The Wnt signaling pathway is critically involved in orchestrating cellular functions such as proliferation, migration, survival, and cell fate determination during development. Given its pivotal role in cellular communication, aberrant Wnt signaling has been extensively linked to the pathogenesis of various diseases. This review offers an in-depth analysis of the Wnt pathway, detailing its signal transduction mechanisms and principal components. Furthermore, the complex network of interactions between Wnt cascades and other key signaling pathways, such as Notch, Hedgehog, TGF-β, FGF, and NF-κB, is explored. Genetic mutations affecting the Wnt pathway play a pivotal role in disease progression, with particular emphasis on Wnt signaling's involvement in cancer stem cell biology and the tumor microenvironment. Additionally, this review underscores the diverse mechanisms through which Wnt signaling contributes to diseases such as cardiovascular conditions, neurodegenerative disorders, metabolic syndromes, autoimmune diseases, and cancer. Finally, a comprehensive overview of the therapeutic progress targeting Wnt signaling was given, and the latest progress in disease treatment targeting key components of the Wnt signaling pathway was summarized in detail, including Wnt ligands/receptors, β-catenin destruction complexes, and β-catenin/TCF transcription complexes. The development of small molecule inhibitors, monoclonal antibodies, and combination therapy strategies was emphasized, while the current potential therapeutic challenges were summarized. This aims to enhance the current understanding of this key pathway.

Novel insights into taxane pharmacology: An update on drug resistance mechanisms, immunomodulation and drug delivery strategies

Taxanes are effective in several solid tumors. Paclitaxel, the main clinically available taxane, was approved in the early nineties, for the treatment of ovarian cancer and later on, together with the analogs docetaxel and cabazitaxel, for other malignancies. By interfering with microtubule function and impairing the separation of sister cells at mitosis, taxanes act as antimitotic agents, thereby counteracting the high proliferation rate of cancer cells. The action of taxanes goes beyond their antimitotic function because their main cellular targets, the microtubules, participate in multiple processes such as intracellular transport and cell shape maintenance. The clinical efficacy of taxanes is limited by the development of multiple resistance mechanisms. Among these, extracellular vesicles have emerged as new players. In addition, taxane metronomic schedules shows an impact on the tumor microenvironment reflected by antiangiogenic and immunomodulatory effects, an aspect of growing interest considering their inclusion in treatment regimens with immunotherapeutics. Preclinical studies have paved the bases for synergistic combinations of taxanes both with conventional and targeted agents. A variety of drug delivery strategies have provided novel opportunities to increase the drug activity. The ability of taxanes to orchestrate different cellular effects amenable to modulation suggests novel options to improve cures in lethal malignancies.

Disruption of the β-catenin destruction complex via Ephexin1-Axin1 interaction promotes colorectal cancer proliferation

Wnt signaling is essential for cell growth and tumor formation and is abnormally activated in colorectal cancer (CRC), contributing to tumor progression; however, the specific role and regulatory mechanisms involved in tumor development remain unclear. Here, we show that Ephexin1, a guanine nucleotide exchange factor, is significantly overexpressed in CRC and is correlated with increased Wnt/β-catenin pathway activity. Through comprehensive analysis, including RNA sequencing data from TCGA and functional assays, we observed that Ephexin1 promotes tumor proliferation and migration by activating the Wnt/β-catenin pathway. This effect was mediated by the interaction of Ephexin1 with Axin1, a critical component of the β-catenin destruction complex, which in turn enhanced the stability and activity of β-catenin in signaling pathways critical for tumor development. Importantly, our findings also suggest that targeting Ephexin1 may increase the efficacy of Wnt/β-catenin pathway inhibitors in CRC treatment. These findings highlight the potential of targeting Ephexin1 as a strategy for developing effective treatments for CRC, suggesting a novel and promising approach to therapy aimed at inhibiting cancer progression.

Small-molecule inhibitors of WNT signalling in cancer therapy and their links to autophagy and apoptosis

Cancer represents an intricate and heterogeneous ailment that evolves from a multitude of epigenetic and genetic variations that disrupt normal cellular function. The WNT/β-catenin pathway is essential in maintaining the balance between cell renewal and differentiation in various tissues. Abnormal activation of this pathway can lead to uncontrolled cell growth and initiate cancer across a variety of tissues such as the colon, skin, liver, and ovary. It enhances characteristics that lead to cancer progression, including angiogenesis, invasion and metastasis. Processes like autophagy and apoptosis which regulate cell death and play a crucial role in maintaining cellular equilibrium are also intimately linked with WNT/ β-catenin pathway. Thus, targeting WNT pathway has become a key strategy in developing antitumor therapies. Employing small molecule inhibitors has emerged as a targeted therapy to improve the clinical outcome compared to conventional cancer treatments. Many strategies using small molecule inhibitors for modulating the WNT/β-catenin pathway, such as hindering WNT ligands' secretion or interaction, disrupting receptor complex, and blocking the nuclear translocation of β-catenin have been investigated. These interventions have shown promise in both preclinical and clinical settings. This review provides a comprehensive understanding of the role of WNT/β-catenin signalling pathway's role in cancer, emphasizing its regulation of autophagy and apoptosis. Our goal is to highlight the potential of specific small molecule inhibitors targeting this pathway, fostering the development of novel, tailored cancer treatments.

Therapeutic Chemoresistance in Ovarian Cancer: Emerging Hallmarks, Signaling Mechanisms and Alternative Pathways

Ovarian cancer is the fifth leading cause of mortality and the most lethal gynecologic malignancy among females. It may arise from atypical borderline tumors (Type I) or serous tubal intraepithelial carcinoma (Type II). The diagnosis of cancer at its early stages is difficult because of non-specific symptoms, most patients are diagnosed at the advanced stage. Several drugs and therapeutic strategies are available to treat ovarian cancer such as surgery, chemotherapy, neoadjuvant therapy, and maintenance therapy. However, the cancer cells have developed resistance to a number of available therapies causing treatment failure. This emerging chemoresistance in ovarian cancer cells is becoming an obstacle due to alterations in multiple cellular processes. These processes involve altered drug target response, drug pumps, detoxification systems, lower sensitivity to apoptosis, and altered proliferation, and are responsible for developing resistance to anticancer medicines. Various research reports have evidenced that these altered processes might play a role in the emergence of resistance. This review addresses the recent advances in understanding the underlying mechanisms of ovarian cancer resistance and covers sophisticated alternative pathways to overcome these resistance mechanisms in patients.

FATS inhibits the Wnt pathway and induces apoptosis through degradation of MYH9 and enhances sensitivity to paclitaxel in breast cancer

Breast cancer is one of the most prevalent and diverse malignancies, and, with global cases increasing, the need for biomarkers to inform individual sensitivity to chemotherapeutics has never been greater. Our retrospective clinical analysis predicted that the expression of the fragile site-associated tumor suppressor (FATS) gene was associated with the sensitivity of breast cancer to neoadjuvant chemotherapy with paclitaxel. In vitro experiments subsequently demonstrated that FATS significantly increased the inhibitory effects of paclitaxel on breast cancer cells' migration, growth, and survival. An interaction screen revealed that FATS interacted with MYH9 and promoted its degradation via the ubiquitin-proteasome pathway, thereby downregulating Wnt signaling. By overexpressing FATS and MYH9, we demonstrated that FATS enhanced paclitaxel-induced apoptosis in breast cancer cells by degrading MYH9 to downregulate the Wnt pathway. We also demonstrated in a mouse xenograft model that FATS significantly increased the chemosensitivity of breast cancer cells to paclitaxel in vivo. This study presents a new mechanism by which FATS interacts with MYH9 to suppress the Wnt/β-catenin signaling pathway and induce apoptosis, thus enhancing the sensitivity of breast cancer cells to paclitaxel chemotherapy. The results also propose novel biomarkers for predicting breast cancer sensitivity to neoadjuvant chemotherapy with paclitaxel. Finally, we provide in vivo evidence that the combination of paclitaxel with IWR-1, a novel Wnt pathway inhibitor, synergistically suppresses breast cancer growth, laying the foundation for future trials with this drug combination. These results therefore provide a number of potential solutions for more precise treatment of patients with breast cancer in the future.

The Wnt signaling pathway in hepatocellular carcinoma: Regulatory mechanisms and therapeutic prospects

Hepatocellular carcinoma (HCC) is a malignant tumor that arises from hepatocytes. Multiple signaling pathways play a regulatory role in the occurrence and development of HCC, with the Wnt signaling pathway being one of the primary regulatory pathways. In normal hepatocytes, the Wnt signaling pathway maintains cell regeneration and organ development. However, when aberrant activated, the Wnt pathway is closely associated with invasion, cancer stem cells(CSCs), drug resistance, and immune evasion in HCC. Among these factors, the development of drug resistance is one of the most important factors affecting the efficacy of HCC treatment. These mechanisms form the basis for tumor cell adaptation and evolution within the body, enabling continuous changes in tumor cells, resistance to drugs and immune system attacks, leading to metastasis and recurrence. In recent years, there have been numerous new discoveries regarding these mechanisms. An increasing number of drugs targeting the Wnt signaling pathway have been developed, with some already entering clinical trials. Therefore, this review encompasses the latest research on the role of the Wnt signaling pathway in the onset and progression of HCC, as well as advancements in its therapeutic strategies.

Role of Wnt/β-catenin pathway in cancer drug resistance: Insights into molecular aspects of major solid tumors

Adaptive resistance to conventional and targeted therapies remains one of the major obstacles in the effective management of cancer. Aberrant activation of key signaling mechanisms plays a pivotal role in modulating resistance to drugs. An evolutionarily conserved Wnt/β-catenin pathway is one of the signaling cascades which regulate resistance to drugs. Elevated Wnt signaling confers resistance to anticancer therapies, either through direct activation of its target genes or via indirect mechanisms and crosstalk over other signaling pathways. Involvement of the Wnt/β-catenin pathway in cancer hallmarks like inhibition of apoptosis, promotion of invasion and metastasis and cancer stem cell maintenance makes this pathway a potential target to exploit for addressing drug resistance. Accumulating evidences suggest a critical role of Wnt/β-catenin pathway in imparting resistance across multiple cancers including PDAC, NSCLC, TNBC, etc. Here we present a comprehensive assessment of how Wnt/β-catenin pathway mediates cancer drug resistance in majority of the solid tumors. We take a deep dive into the Wnt/β-catenin signaling-mediated modulation of cellular and downstream molecular mechanisms and their impact on cancer resistance.

Blocking the WNT/β-catenin pathway in cancer treatment:pharmacological targets and drug therapeutic potential

The WNT/β-catenin signaling pathway plays crucial roles in tumorigenesis and relapse, metastasis, drug resistance, and tumor stemness maintenance. In most tumors, the WNT/β-catenin signaling pathway is often aberrantly activated. The therapeutic usefulness of inhibition of WNT/β-catenin signaling has been reported to improve the efficiency of different cancer treatments and this inhibition of signaling has been carried out using different methods including pharmacological agents, short interfering RNA (siRNA), and antibodies. Here, we review the WNT-inhibitory effects of some FDA-approved drugs and natural products in cancer treatment and focus on recent progress of the WNT signaling inhibitors in improving the efficiency of chemotherapy, immunotherapy, gene therapy, and physical therapy. We also classified these FDA-approved drugs and natural products according to their structure and physicochemical properties, and introduced briefly their potential mechanisms of inhibiting the WNT signaling pathway. The review provides a comprehensive understanding of inhibitors of WNT/β-catenin pathway in various cancer therapeutics. This will benefit novel WNT inhibitor development and optimal clinical use of WNT signaling-related drugs in synergistic cancer therapy.

Breast cancer drug resistance: Decoding the roles of Hippo pathway crosstalk

The most significant factors that lead to cancer-related death in breast cancer (BC) patients include drug resistance, migration, invasion, and metastasis. Several signaling pathways are involved in the development of BC. The different types of BC are initially sensitive to chemotherapy, and drug resistance can occur through multiple molecular mechanisms. Regardless of developing targeted Therapy, due to the heterogenic nature and complexity of drug resistance, it is a major clinical challenge with the low survival rate in BC patients. The deregulation of several signaling pathways, particularly the Hippo pathway (HP), is one of the most recent findings about the molecular mechanisms of drug resistance in BC, which are summarized in this review. Given that HP is one of the recent cancer research hotspots, this review focuses on its implication in BC drug resistance. Unraveling the different molecular basis of HP through its crosstalk with other signaling pathways, and determining the effectiveness of HP inhibitors can provide new insights into possible therapeutic strategies for overcoming chemoresistance in BC.

Why Is Wnt/β-Catenin Not Yet Targeted in Routine Cancer Care?

Despite significant progress in cancer prevention, screening, and treatment, the still limited number of therapeutic options is an obstacle towards increasing the cancer cure rate. In recent years, many efforts were put forth to develop therapeutics that selectively target different components of the oncogenic Wnt/β-catenin signaling pathway. These include small molecule inhibitors, antibodies, and more recently, gene-based approaches. Although some of them showed promising outcomes in clinical trials, the Wnt/β-catenin pathway is still not targeted in routine clinical practice for cancer management. As for most anticancer treatments, a critical limitation to the use of Wnt/β-catenin inhibitors is their therapeutic index, i.e., the difficulty of combining effective anticancer activity with acceptable toxicity. Protecting healthy tissues from the effects of Wnt/β-catenin inhibitors is a major issue due to the vital role of the Wnt/β-catenin signaling pathway in adult tissue homeostasis and regeneration. In this review, we provide an up-to-date summary of clinical trials on Wnt/β-catenin pathway inhibitors, examine their anti-tumor activity and associated adverse events, and explore strategies under development to improve the benefit/risk profile of this therapeutic approach.

Intracellular domain of epithelial cell adhesion molecule induces Wnt receptor transcription to promote colorectal cancer progression

BACKGROUND

Epithelial cell adhesion molecule (EpCAM) has been widely studied as a tumor antigen due to its expression in varieties of solid tumors. Moreover, the glycoprotein contributes to critical cancer-associated cellular functionalities via its extracellular (EpEX) and intracellular (EpICD) domains. In colorectal cancer (CRC), EpCAM has been implicated in the Wnt signaling pathway, as EpICD and β-Catenin are coordinately translocated to the nucleus. Once in the nucleus, EpICD transcriptionally regulates EpCAM target genes that; however, remains unclear whether Wnt signaling is modulated by EpICD activity.

METHODS

Patient-derived organoids (PDOs), patient-derived xenografts (PDXs), and various CRC cell lines were used to study the roles of EpCAM and EpICD in Wnt receptor expression. Fluorescence and confocal microscopy were used to analyze tumors isolated from PDX and other xenograft models as well as CRC cell lines. EpCAM signaling was intervened with our humanized form of EpCAM neutralizing antibody, hEpAb2-6. Wnt receptor promoters under luciferase reporters were constructed to examine the effects of EpICD. Luciferase reporter assays were performed to evaluate promoter, γ-secretase and Wnt activity. Functional assays including in vivo tumor formation, organoid formation, spheroid and colony formation experiments were performed to study Wnt related phenomena. The therapeutic potential of EpCAM suppression by hEpAb2-6 was evaluated in xenograft and orthotopic models of human CRC.

RESULTS

EpICD interacted with the promoters of Wnt receptors (FZD6 and LRP5/6) thus upregulated their transcriptional activity inducing Wnt signaling. Furthermore, activation of Wnt-pathway-associated kinases in the β-Catenin destruction complex (GSK3β and CK1) induced γ-secretase activity to augment EpICD shedding, establishing a positive-feedback loop. Our hEpAb2-6 antibody blocked EpICD-mediated upregulation of Wnt receptor expressions and conferred therapeutic benefits in both PDX and orthotopic models of human CRC.

CONCLUSIONS

This study uncovers relevant functions of EpCAM where Wnt receptors are upregulated via the transcriptional co-factor activity of EpICD. The resultant enhancement of Wnt signaling induces γ-secretase activity further stimulating EpICD cleavage and its nuclear translocation. Our humanized anti-EpCAM antibody hEpAb2-6 blocks these mechanisms and may thereby provide therapeutic benefit in CRC.

Wnt signaling in gastric cancer: current progress and future prospects

Levels of the Wnt pathway components are abnormally altered in gastric cancer cells, leading to malignant cell proliferation, invasion and metastasis, poor prognosis and chemoresistance. Therefore, it is important to understand the mechanism of Wnt signaling pathway in gastric cancer. We systematically reviewed the molecular mechanisms of the Wnt pathway in gastric cancer development; and summarize the progression and the challenges of research on molecular agents of the Wnt pathway.

Signalling interaction between β-catenin and other signalling molecules during osteoarthritis development

Osteoarthritis (OA) is the most prevalent disorder of synovial joint affecting multiple joints. In the past decade, we have witnessed conceptual switch of OA pathogenesis from a 'wear and tear' disease to a disease affecting entire joint. Extensive studies have been conducted to understand the underlying mechanisms of OA using genetic mouse models and ex vivo joint tissues derived from individuals with OA. These studies revealed that multiple signalling pathways are involved in OA development, including the canonical Wnt/β-catenin signalling and its interaction with other signalling pathways, such as transforming growth factor β (TGF-β), bone morphogenic protein (BMP), Indian Hedgehog (Ihh), nuclear factor κB (NF-κB), fibroblast growth factor (FGF), and Notch. The identification of signalling interaction and underlying mechanisms are currently underway and the specific molecule(s) and key signalling pathway(s) playing a decisive role in OA development need to be evaluated. This review will focus on recent progresses in understanding of the critical role of Wnt/β-catenin signalling in OA pathogenesis and interaction of β-catenin with other pathways, such as TGF-β, BMP, Notch, Ihh, NF-κB, and FGF. Understanding of these novel insights into the interaction of β-catenin with other pathways and its integration into a complex gene regulatory network during OA development will help us identify the key signalling pathway of OA pathogenesis leading to the discovery of novel therapeutic strategies for OA intervention.

Informed by Cancer Stem Cells of Solid Tumors: Advances in Treatments Targeting Tumor-Promoting Factors and Pathways

Cancer stem cells (CSCs) represent a subpopulation within tumors that promote cancer progression, metastasis, and recurrence due to their self-renewal capacity and resistance to conventional therapies. CSC-specific markers and signaling pathways highly active in CSCs have emerged as a promising strategy for improving patient outcomes. This review provides a comprehensive overview of the therapeutic targets associated with CSCs of solid tumors across various cancer types, including key molecular markers aldehyde dehydrogenases, CD44, epithelial cellular adhesion molecule, and CD133 and signaling pathways such as Wnt/β-catenin, Notch, and Sonic Hedgehog. We discuss a wide array of therapeutic modalities ranging from targeted antibodies, small molecule inhibitors, and near-infrared photoimmunotherapy to advanced genetic approaches like RNA interference, CRISPR/Cas9 technology, aptamers, antisense oligonucleotides, chimeric antigen receptor (CAR) T cells, CAR natural killer cells, bispecific T cell engagers, immunotoxins, drug-antibody conjugates, therapeutic peptides, and dendritic cell vaccines. This review spans developments from preclinical investigations to ongoing clinical trials, highlighting the innovative targeting strategies that have been informed by CSC-associated pathways and molecules to overcome therapeutic resistance. We aim to provide insights into the potential of these therapies to revolutionize cancer treatment, underscoring the critical need for a multi-faceted approach in the battle against cancer. This comprehensive analysis demonstrates how advances made in the CSC field have informed significant developments in novel targeted therapeutic approaches, with the ultimate goal of achieving more effective and durable responses in cancer patients.

Recurrent mutations in tumor suppressor FBXW7 bypass Wnt/β-catenin addiction in cancer

Pathologic Wnt/β-catenin signaling drives various cancers, leading to multiple approaches to drug this pathway. Appropriate patient selection can maximize success of these interventions. Wnt ligand addiction is a druggable vulnerability in RNF43-mutant/RSPO-fusion cancers. However, pharmacologically targeting the biogenesis of Wnt ligands, e.g., with PORCN inhibitors, has shown mixed therapeutic responses, possibly due to tumor heterogeneity. Here, we show that the tumor suppressor FBXW7 is frequently mutated in RNF43-mutant/RSPO-fusion tumors, and FBXW7 mutations cause intrinsic resistance to anti-Wnt therapies. Mechanistically, FBXW7 inactivation stabilizes multiple oncoproteins including Cyclin E and MYC and antagonizes the cytostatic effect of Wnt inhibitors. Moreover, although FBXW7 mutations do not mitigate β-catenin degradation upon Wnt inhibition, FBXW7-mutant RNF43-mutant/RSPO-fusion cancers instead lose dependence on β-catenin signaling, accompanied by dedifferentiation and loss of lineage specificity. These FBXW7-mutant Wnt/β-catenin-independent tumors are susceptible to multi-cyclin-dependent kinase inhibition. An in-depth understanding of primary resistance to anti-Wnt/β-catenin therapies allows for more appropriate patient selection and use of alternative mechanism-based therapies.

Clinical and Preclinical Targeting of Oncogenic Pathways in PDAC: Targeted Therapeutic Approaches for the Deadliest Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related death worldwide. It is commonly diagnosed in advanced stages and therapeutic interventions are typically constrained to systemic chemotherapy, which yields only modest clinical outcomes. In this review, we examine recent developments in targeted therapy tailored to address distinct molecular pathway alteration required for PDAC. Our review delineates the principal signaling pathways and molecular mechanisms implicated in the initiation and progression of PDAC. Subsequently, we provide an overview of prevailing guidelines, ongoing investigations, and prospective research trajectories related to targeted therapeutic interventions, drawing insights from randomized clinical trials and other pertinent studies. This review focus on a comprehensive examination of preclinical and clinical data substantiating the efficacy of these therapeutic modalities, emphasizing the potential of combinatorial regimens and novel therapies to enhance the quality of life for individuals afflicted with PDAC. Lastly, the review delves into the contemporary application and ongoing research endeavors concerning targeted therapy for PDAC. This synthesis serves to bridge the molecular elucidation of PDAC with its clinical implications, the evolution of innovative therapeutic strategies, and the changing landscape of treatment approaches.

Tumor-associated macrophages: an effective player of the tumor microenvironment

Cancer progression is primarily caused by interactions between transformed cells and the components of the tumor microenvironment (TME). TAMs (tumor-associated macrophages) make up the majority of the invading immune components, which are further categorized as anti-tumor M1 and pro-tumor M2 subtypes. While M1 is known to have anti-cancer properties, M2 is recognized to extend a protective role to the tumor. As a result, the tumor manipulates the TME in such a way that it induces macrophage infiltration and M1 to M2 switching bias to secure its survival. This M2-TAM bias in the TME promotes cancer cell proliferation, neoangiogenesis, lymphangiogenesis, epithelial-to-mesenchymal transition, matrix remodeling for metastatic support, and TME manipulation to an immunosuppressive state. TAMs additionally promote the emergence of cancer stem cells (CSCs), which are known for their ability to originate, metastasize, and relapse into tumors. CSCs also help M2-TAM by revealing immune escape and survival strategies during the initiation and relapse phases. This review describes the reasons for immunotherapy failure and, thereby, devises better strategies to impair the tumor-TAM crosstalk. This study will shed light on the understudied TAM-mediated tumor progression and address the much-needed holistic approach to anti-cancer therapy, which encompasses targeting cancer cells, CSCs, and TAMs all at the same time.

Paclitaxel promotes mTOR signaling-mediated apoptosis in esophageal cancer cells by targeting MUC20

BACKGROUND

The aim of this study was to analyze the effect of paclitaxel on the apoptosis of esophageal cancer cells in relation to MUC20.

METHODS

RT-qPCR analysis, a CCK-8 assay, western blotting, and flow cytometry were used to analyze the anticancer effects of paclitaxel treatment or OE-MUC20 in vitro and in vivo.

RESULTS

The in vitro results showed that paclitaxel significantly induced MUC20 upregulation and that paclitaxel treatment or OE-MUC20 significantly decreased esophageal cancer cell viability and increased mTOR signaling activation and apoptosis. In addition, PKM2, a key downstream molecule of mTOR signaling, similarly showed significant upregulation after paclitaxel treatment in cells with OE-MUC20, and its expression was attenuated after treatment with mTOR inhibitors. In a nude mouse model, tumor growth was slow in the OE-MUC20 group and accelerated after inhibition of mTOR signaling.

CONCLUSION

These data suggest that MUC20 is an important target of paclitaxel in esophageal cancer and promotes apoptosis through activation of mTOR signaling.

Regulation and signaling pathways in cancer stem cells: implications for targeted therapy for cancer

Cancer stem cells (CSCs), initially identified in leukemia in 1994, constitute a distinct subset of tumor cells characterized by surface markers such as CD133, CD44, and ALDH. Their behavior is regulated through a complex interplay of networks, including transcriptional, post-transcriptional, epigenetic, tumor microenvironment (TME), and epithelial-mesenchymal transition (EMT) factors. Numerous signaling pathways were found to be involved in the regulatory network of CSCs. The maintenance of CSC characteristics plays a pivotal role in driving CSC-associated tumor metastasis and conferring resistance to therapy. Consequently, CSCs have emerged as promising targets in cancer treatment. To date, researchers have developed several anticancer agents tailored to specifically target CSCs, with some of these treatment strategies currently undergoing preclinical or clinical trials. In this review, we outline the origin and biological characteristics of CSCs, explore the regulatory networks governing CSCs, discuss the signaling pathways implicated in these networks, and investigate the influential factors contributing to therapy resistance in CSCs. Finally, we offer insights into preclinical and clinical agents designed to eliminate CSCs.

"DEPHENCE" system-a novel regimen of therapy that is urgently needed in the high-grade serous ovarian cancer-a focus on anti-cancer stem cell and anti-tumor microenvironment targeted therapies

Ovarian cancer, especially high-grade serous type, is the most lethal gynecological malignancy. The lack of screening programs and the scarcity of symptomatology result in the late diagnosis in about 75% of affected women. Despite very demanding and aggressive surgical treatment, multiple-line chemotherapy regimens and both approved and clinically tested targeted therapies, the overall survival of patients is still unsatisfactory and disappointing. Research studies have recently brought some more understanding of the molecular diversity of the ovarian cancer, its unique intraperitoneal biology, the role of cancer stem cells, and the complexity of tumor microenvironment. There is a growing body of evidence that individualization of the treatment adjusted to the molecular and biochemical signature of the tumor as well as to the medical status of the patient should replace or supplement the foregoing therapy. In this review, we have proposed the principles of the novel regimen of the therapy that we called the "DEPHENCE" system, and we have extensively discussed the results of the studies focused on the ovarian cancer stem cells, other components of cancer metastatic niche, and, finally, clinical trials targeting these two environments. Through this, we have tried to present the evolving landscape of treatment options and put flesh on the experimental approach to attack the high-grade serous ovarian cancer multidirectionally, corresponding to the "DEPHENCE" system postulates.

Quercetin induces MGMT+ glioblastoma cells apoptosis via dual inhibition of Wnt3a/β-Catenin and Akt/NF-κB signaling pathways

BACKGROUND

Surgical resection combined with radiotherapy and chemotherapy remains a common clinical treatment for glioblastoma multiforme (GBM). However, the therapeutic outcomes have not been satisfying due to drug resistance and other factors. Quercetin, a phytoingredient capable of crossing the blood-brain barrier, has shown effectiveness in the treatment of various solid tumors. Nevertheless, the potential of quercetin in GBM treatment has not been adequately explored.

PURPOSE

This study aims to investigate the effects and mechanisms of quercetin on MGMT⁺GBM cells.

METHODS

The potential targets and mechanisms of quercetin in glioma treatment were predicted based on network pharmacology and molecular docking. The effects of quercetin on cell inhibition rate, cell migration ability, cell cycle arrest, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), Mitochondrial superoxide formation and apoptosis were measured by the CCK8 assay, wound healing assay, PI/RNase staining, JC-1 assay, DCFH-DA assay, MitoSOX staining and Annexin V-FITC/PI double staining, respectively. The methylation status of the MGMT promoter was assessed through methylation-specific polymerase chain reaction (MS-PCR). DNA damage was quantified by alkaline/neutral comet assay and TUNEL assay. The intracellular localization and expression of NF-κB and MGMT were revealed by immunofluorescence. The expression of migration-related proteins, matrix metalloproteinases, apoptosis-related proteins, cyclins, DNA damage/repair enzymes and related pathway proteins was detected by Western blot.

RESULTS

Network pharmacology identified 96 targets and potential molecular mechanisms of quercetin in glioma treatment. Subsequent experiments confirmed the synergistic effect of quercetin in combination with temozolomide (TMZ) on T98G cells. Quercetin significantly suppressed the growth and migration of human GBM T98G cells, induced apoptosis, and arrested cells in the S-phase cell cycle. The collapse of mitochondrial membrane potential, ROS generation, enhanced Bax/Bcl-2 ratio, and strengthened cleaved-Caspase 9 and cleaved-Caspase 3 suggested the involvement of ROS-mediated mitochondria-dependent apoptosis in the process of quercetin-induced apoptosis. In addition, quercetin-induced apoptosis was accompanied by intense DNA double-strand breaks (DSBs), γH2AX foci formation, methylation of MGMT promoter, increased cleaved-PARP, and reduced MGMT expression. Quercetin may influence the expression of the key DNA repair enzyme, MGMT, by dual suppression of the Wnt3a/β-Catenin and the Akt/NF-κB signaling pathways, thereby promoting apoptosis. Inhibition of Wnt3a and Akt using specific inhibitors hindered MGMT expression.

CONCLUSION

Our study provides the first evidence that quercetin may induce apoptosis in MGMT⁺GBM cells via dual inhibition of the Wnt3a/β-Catenin pathway and the Akt/NF-κB signaling pathway. These findings suggest that quercetin could be a novel agent for improving GBM treatment, especially in TMZ-resistant GBM with high MGMT expression.

The recent progress of peptide regulators for the Wnt/β-catenin signaling pathway

Wnt signaling plays an important role in many biological processes such as stem cell self-renewal, cell proliferation, migration, and differentiation. The β-catenin-dependent signaling pathway mainly regulates cell proliferation, differentiation, and migration. In the Wnt/β-catenin signaling pathway, the Wnt family ligands transduce signals through LRP5/6 and Frizzled receptors to the Wnt/β-catenin signaling cascades. Wnt-targeted therapy has garnered extensive attention. The most commonly used approach in targeted therapy is small-molecule regulators. However, it is difficult for small-molecule regulators to make great progress due to their inherent defects. Therapeutic peptide regulators targeting the Wnt signaling pathway have become an alternative therapy, promising to fill the gaps in the clinical application of small-molecule regulators. In this review, we describe recent advances in peptide regulators for Wnt/β-catenin signaling.

Oncogenic metabolic reprogramming in breast cancer: focus on signaling pathways and mitochondrial genes

Oncogenic metabolic reprogramming impacts the abundance of key metabolites that regulate signaling and epigenetics. Metabolic vulnerability in the cancer cell is evident from the Warburg effect. The research on metabolism in the progression and survival of breast cancer (BC) is under focus. Oncogenic signal activation and loss of tumor suppressor are important regulators of tumor cell metabolism. Several intrinsic and extrinsic factors contribute to metabolic reprogramming. The molecular mechanisms underpinning metabolic reprogramming in BC are extensive and only partially defined. Various signaling pathways involved in the metabolism play a significant role in the modulation of BC. Notably, PI3K/AKT/mTOR pathway, lactate-ERK/STAT3 signaling, loss of the tumor suppressor Ras, Myc, oxidative stress, activation of the cellular hypoxic response and acidosis contribute to different metabolic reprogramming phenotypes linked to enhanced glycolysis. The alterations in mitochondrial genes have also been elaborated upon along with their functional implications. The outcome of these active research areas might contribute to the development of novel therapeutic interventions and the remodeling of known drugs.

Scope of Wnt signaling in the precise diagnosis and treatment of breast cancer

Malignant breast cancers are responsible for a growing number of deaths among women globally. The latest research has demonstrated that Wnt signaling is pivotal in this disease, regulating a safe microenvironment for the growth and proliferation of cancer cells {AuQ: Edit OK?}, sustained stemness, resistance to therapy, and aggregate formation. The three highly conserved {AuQ: Edit OK?} Wnt signaling pathways, Wnt-planar cell polarity (PCP), Wnt/β-catenin signaling and Wnt-Ca²⁺ signaling, assume various roles in the maintenance and amelioration of breast cancer. In this review, we examine ongoing studies on the Wnt signaling pathways and discuss how dysregulation of these pathways promotes breast cancers. We also look at how Wnt dysregulation could be exploited to foster new treatments for malignant breast cancers.

Combination CDC-like kinase inhibition (CLK)/Dual-specificity tyrosine-regulated kinase (DYRK) and taxane therapy in CTNNB1-mutated endometrial cancer

SM08502 (cirtuvivint) is a novel pan CDC-like kinase (CLK) and Dual specificity tyrosine kinase (DYRK) inhibitor that targets mRNA splicing and is optimized for Wnt pathway inhibition. Previous evaluation of single agent CLK/DYRK inhibition (SM04690) demonstrated inhibition of tumor progression and β-catenin/TCF transcriptional activity in CTNNB1-mutant endometrial cancer (EC). In-vitro analysis of SM08502 similarly decreases Wnt transcriptional activity and cellular proliferation while increasing cellular apoptosis. SM08502 is an active single-agent therapy with IC50's in the nanomolar range for all EC cell lines evaluated. Combination of SM08502 with paclitaxel has synergistic effect in vitro, as demonstrated by Combination Index <1, and inhibits tumor progression in four endometrial cancer models (HEC265, Ishikawa, Ishikawa-S33Y, and SNGM). In our in vivo mouse models, Ishikawa demonstrated significantly lower tumor volumes of combination vs SM08502 alone (Repeated Measures one-way ANOVA, p = 0.04), but not vs paclitaxel alone. HEC265, SNGM, and Ishikawa-S33Y tumors all had significantly lower tumor volumes with combination SM08502 and paclitaxel compared to single-agent paclitaxel (Repeated Measures one-way ANOVA, p = 0.01, 0.004, and 0.0008, respectively) or single-agent SM08502 (Repeated Measures one-way ANOVA, p = 0.002, 0.005, and 0.01, respectively) alone. Mechanistically, treatment with SM08502 increases alternative splicing (AS) events compared to treatment with paclitaxel. AS regulation is an important post-transcriptional mechanism associated with the oncogenic process in many cancers, including EC. Results from these studies have led to a Phase I evaluation of this combination in recurrent EC.

Wnt Signaling Inhibitors and Their Promising Role in Tumor Treatment

In a continuous search for the improvement of antitumor therapies, the inhibition of the Wnt signaling pathway has been recognized as a promising target. The altered functioning of the Wnt signaling in human tumors points to the strategy of the inhibition of its activity that would impact the clinical outcomes and survival of patients. Because the Wnt pathway is often mutated or epigenetically altered in tumors, which promotes its activation, inhibitors of Wnt signaling are being intensively investigated. It has been shown that knocking down specific components of the Wnt pathway has inhibitory effects on tumor growth in vivo and in vitro. Thus, similar effects are expected from the application of Wnt inhibitors. In the last decades, molecules acting as inhibitors on the pathway’s specific molecular levels have been identified and characterized. This review will discuss the inhibitors of the canonical Wnt pathway, summarize knowledge on their effectiveness as therapeutics, and debate their side effects. The role of the components frequently mutated in various tumors that are principal targets for Wnt inhibitors is also going to be brought to the reader’s attention. Some of the molecules identified as Wnt pathway inhibitors have reached early stages of clinical trials, and some have only just been discovered. All things considered, inhibition of the Wnt signaling pathway shows potential for the development of future therapies.

Biological functions and molecular interactions of Wnt/β-catenin in breast cancer: Revisiting signaling networks

Changes in lifestyle such as physical activity and eating habits have been one of the main reasons for development of various diseases in modern world, especially cancer. However, role of genetic factors in initiation of cancer cannot be ignored and Wnt/β-catenin signaling is such factor that can affect tumor progression. Breast tumor is the most malignant tumor in females and it causes high mortality and morbidity around the world. The survival and prognosis of patients are not still desirable, although there have been advances in introducing new kinds of therapies and diagnosis. The present review provides an update of Wnt/β-catenin function in breast cancer malignancy. The upregulation of Wnt is commonly observed during progression of breast tumor and confirms that tumor cells are dependent on this pathway Wnt/β-catenin induction prevents apoptosis that is of importance for mediating drug resistance. Furthermore, Wnt/β-catenin signaling induces DNA damage repair in ameliorating radio-resistance. Wnt/β-catenin enhances proliferation and metastasis of breast tumor. Wnt/β-catenin induces EMT and elevates MMP expression. Furthermore, Wnt/β-catenin participates in tumor microenvironment remodeling and due to its tumor-promoting factor, drugs for its suppression have been developed. Different kinds of upstream mediators Wnt/β-catenin signaling in breast cancer have been recognized that their targeting is a therapeutic approach. Finally, Wnt/β-catenin can be considered as a biomarker in clinical trials.

Dishevelled 2 regulates cancer cell proliferation and T cell mediated immunity in HER2-positive breast cancer

BACKGROUND

Dishevelled paralogs (DVL1, 2, 3) are key mediators of Wnt pathway playing a role in constitutive oncogenic signaling influencing the tumor microenvironment. While previous studies showed correlation of β-catenin with T cell gene expression, little is known about the role of DVL2 in modulating tumor immunity. This study aimed to uncover the novel interaction between DVL2 and HER2-positive (HER2+) breast cancer (BC) in regulating tumor immunity and disease progression.

METHODS

DVL2 loss of function studies were performed with or without a clinically approved HER2 inhibitor, Neratinib in two different HER2+ BC cell lines. We analyzed RNA (RT-qPCR) and protein (western blot) expression of classic Wnt markers and performed cell proliferation and cell cycle analyses by live cell imaging and flow cytometry, respectively. A pilot study in 24 HER2+ BC patients was performed to dissect the role of DVL2 in tumor immunity. Retrospective chart review on patient records and banked tissue histology were performed. Data were analyzed in SPSS (version 25) and GraphPad Prism (version 7) at a significance p < 0.05.

RESULTS

DVL2 regulates the transcription of immune modulatory genes involved in antigen presentation and T cell maintenance. DVL2 loss of function down regulated mRNA expression of Wnt target genes involved in cell proliferation, migration, invasion in HER2+ BC cell lines (±Neratinib). Similarly, live cell proliferation and cell cycle analyses reveal that DVL2 knockdown (±Neratinib) resulted in reduced proliferation, higher growth arrest (G1), limited mitosis (G2/M) compared to non-targeted control in one of the two cell lines used. Analyses on patient tissues who received neoadjuvant chemotherapy (n = 14) further demonstrate that higher DVL2 expression at baseline biopsy pose a significant negative correlation with % CD8α levels (r = - 0.67, p < 0.05) while have a positive correlation with NLR (r = 0.58, p < 0.05), where high NLR denotes worse cancer prognosis. These results from our pilot study reveal interesting roles of DVL2 proteins in regulating tumor immune microenvironment and clinical predictors of survival in HER2+ BC.

CONCLUSION

Our study demonstrates potential immune regulatory role of DVL2 proteins in HER2+ BC. More in-depth mechanistic studies of DVL paralogs and their influence on anti-tumor immunity may provide insight into DVLs as potential therapeutic targets benefiting BC patients.

WNT signaling in the tumor microenvironment promotes immunosuppression in murine pancreatic cancer

Pancreatic ductal adenocarcinoma (PDA) is associated with activation of WNT signaling. Whether this signaling pathway regulates the tumor microenvironment has remained unexplored. Through single-cell RNA sequencing of human pancreatic cancer, we discovered that tumor-infiltrating CD4+ T cells express TCF7, encoding for the transcription factor TCF1. We conditionally inactivated Tcf7 in CD4 expressing T cells in a mouse model of pancreatic cancer and observed changes in the tumor immune microenvironment, including more CD8+ T cells and fewer regulatory T cells, but also compensatory upregulation of PD-L1. We then used a clinically available inhibitor of Porcupine, a key component of WNT signaling, and observed similar reprogramming of the immune response. WNT signaling inhibition has limited therapeutic window due to toxicity, and PD-L1 blockade has been ineffective in PDA. Here, we show that combination targeting reduces pancreatic cancer growth in an experimental model and might benefit the treatment of pancreatic cancer.

Wnt signaling in liver regeneration, disease, and cancer

The liver exhibits the highest recovery rate from acute injuries. However, in chronic liver disease, the long-term loss of hepatocytes often leads to adverse consequences such as fibrosis, cirrhosis, and liver cancer. The Wnt signaling plays a pivotal role in both liver regeneration and tumorigenesis. Therefore, manipulating the Wnt signaling has become an attractive approach to treating liver disease, including cancer. Nonetheless, given the crucial roles of Wnt signaling in physiological processes, blocking Wnt signaling can also cause several adverse effects. Recent studies have identified cancer-specific regulators of Wnt signaling, which would overcome the limitation of Wnt signaling target approaches. In this review, we discussed the role of Wnt signaling in liver regeneration, precancerous lesion, and liver cancer. Furthermore, we summarized the basic and clinical approaches of Wnt signaling blockade and proposed the therapeutic prospects of cancer-specific Wnt signaling blockade for liver cancer treatment.

Wnt signalling in cell division: from mechanisms to tissue engineering

Wnt signalling is an essential player in tissue formation, notably in the regulation of stem cell function. Wnt signalling is best known for its roles in G1/S progression. However, a complex Wnt programme that also mediates mitotic progression and asymmetric cell division (ACD) is emerging. Recent developments in this area have provided mechanistic insights as well as tools to engineer or target Wnt signalling for translational and therapeutic purposes. Here, we discuss the bidirectional relationship between Wnt activity and mitosis. We emphasise how various Wnt-dependent mechanisms control spindle dynamics, chromosome segregation, and ACD. Finally, we illustrate how knowledge about these mechanisms has been successfully employed in tissue engineering for regenerative medicine applications.

Insight into the role of multiple signaling pathways in regulating cancer stem cells of gynecologic cancers

Mounting evidence has demonstrated that a myriad of developmental signaling pathways, such as the Wnt, Notch, Hedgehog and Hippo, are frequently deregulated and play a critical role in regulating cancer stem cell (CSC) activity in human cancers, including gynecologic malignancies. In this review article, we describe an overview of various signaling pathways in human cancers. We further discuss the developmental roles how these pathways regulate CSCs from experimental evidences in gynecologic cancers. Moreover, we mention several compounds targeting CSCs in gynecologic cancers to enhance the treatment outcomes. Therefore, these signaling pathways might be the potential targets for developing targeted therapy in gynecologic cancers.

Targeting Gastric Cancer Stem Cells to Enhance Treatment Response

Gastric cancer (GC) was the fourth deadliest cancer in the world in 2020, and about 770,000 people died from GC that year. The death of patients with GC is mainly caused by the metastasis, recurrence, and chemotherapy resistance of GC cells. The cancer stem cell theory defines cancer stem cells (CSCs) as a key factor in the metastasis, recurrence, and chemotherapy resistance of cancer. It considers targeting gastric cancer stem cells (GCSCs) to be an effective method for the treatment of GC. For GCSCs, genes or noncoding RNAs are important regulatory factors. Many experimental studies have found that some drugs can target the stemness of gastric cancer by regulating these genes or noncoding RNAs, which may bring new directions for the clinical treatment of gastric cancer. Therefore, this review mainly discusses related genes or noncoding RNAs in GCSCs and drugs that target its stemness, thereby providing some information for the treatment of GC.

Acquisition of taxane resistance by p53 inactivation in ovarian cancer cells

Ovarian cancer is one of the most common gynecologic malignancies in women and has a poor prognosis. Taxanes are a class of standard first-line chemotherapeutic agents for the treatment of ovarian cancer. However, tumor-intrinsic and acquired resistance to taxanes poses major challenges to improving clinical outcomes. Hence, there is an urgent clinical need to understand the mechanisms of resistance in order to discover potential biomarkers and therapeutic strategies to increase taxane sensitivity in ovarian cancer. Here, we report the identification of an association between the TP53 status and taxane sensitivity in ovarian cancer cells through complementary experimental and informatics approaches. We found that TP53 inactivation is associated with taxane resistance in ovarian cancer cells, supported by the evidence from (i) drug sensitivity profiling with bioinformatic analysis of large-scale cancer therapeutic response and genomic datasets and (ii) gene signature identification based on experimental isogenic cell line models. Further, our studies revealed TP53-dependent gene expression patterns, such as overexpression of ACSM3, as potential predictive biomarkers of taxane resistance in ovarian cancer. The TP53-dependent hyperactivation of the WNT/β-catenin pathway discovered herein revealed a potential vulnerability to exploit in developing combination therapeutic strategies. Identification of this genotype-phenotype relationship between the TP53 status and taxane sensitivity sheds light on TP53-directed patient stratification and therapeutic discoveries for ovarian cancer treatment.

Engaging plasticity: Differentiation therapy in solid tumors

Cancer is a systemic heterogeneous disease that can undergo several rounds of latency and activation. Tumor progression evolves by increasing diversity, adaptation to signals from the microenvironment and escape mechanisms from therapy. These dynamic processes indicate necessity for cell plasticity. Epithelial-mesenchymal transition (EMT) plays a major role in facilitating cell plasticity in solid tumors by inducing dedifferentiation and cell type transitions. These two practices, plasticity and dedifferentiation enhance tumor heterogeneity creating a key challenge in cancer treatment. In this review we will explore cancer cell plasticity and elaborate treatment modalities that aspire to overcome such dynamic processes in solid tumors. We will further discuss the therapeutic potential of utilizing enhanced cell plasticity for differentiation therapy.

The Expression of Signaling Genes in Breast Cancer Cells

Simple Summary

The aim of the study was to investigate the effect of a drug for cancer—paclitaxel—on the expression of genes encoding the signaling factors in breast cancer cells outside organisms. The tested cells were harvested from the mammary glands of 36 women with breast cancer. The microarray technology —the carrier with applied DNA samples—was employed for the identification of gene expression. A significant effect of paclitaxel on the genome of breast cancer cells was confirmed. Paclitaxel changed the functions of cancer cell by increasing the expression of the genes encoding signaling proteins. This is the molecule of intercellular communication. The analysis of the results suggests that this cytostatic agent produces a beneficial therapeutic effect at a lower dose (60 ng/mL). In contrast, a high dose of paclitaxel (300 ng/mL) was associated with higher cytotoxicity and this had a negative effect on the tested tumor cells.

Abstract

The aim of the study was to investigate the effect of paclitaxel on the expression of genes encoding signaling factors in breast cancer cells in in vitro conditions after incubation with the said chemotherapeutic. The tested cells were harvested from the mammary glands of 36 patients with early breast cancer. The microarray technology was employed for the identification of gene expression. For this purpose, mRNA isolated from tumor cells was used. A significant effect of paclitaxel on the genome of breast cancer cells was confirmed. Paclitaxel changed the functions of cancer cells by increasing the expression of most genes encoding signaling proteins and receptors. The analysis of the results suggested that this cytostatic agent produces a beneficial therapeutic effect at a lower dose (60 ng/mL). In contrast, a high dose of paclitaxel (300 ng/mL) was associated with a high cytotoxicity.

Exploring the Wnt Pathway as a Therapeutic Target for Prostate Cancer

Aberrant activation of the Wnt pathway is emerging as a frequent event during prostate cancer that can facilitate tumor formation, progression, and therapeutic resistance. Recent discoveries indicate that targeting the Wnt pathway to treat prostate cancer may be efficacious. However, the functional consequence of activating the Wnt pathway during the different stages of prostate cancer progression remains unclear. Preclinical work investigating the efficacy of targeting Wnt signaling for the treatment of prostate cancer, both in primary and metastatic lesions, and improving our molecular understanding of treatment responses is crucial to identifying effective treatment strategies and biomarkers that help guide treatment decisions and improve patient care. In this review, we outline the type of genetic alterations that lead to activated Wnt signaling in prostate cancer, highlight the range of laboratory models used to study the role of Wnt genetic drivers in prostate cancer, and discuss new mechanistic insights into how the Wnt cascade facilitates prostate cancer growth, metastasis, and drug resistance.

A FZD7-specific Antibody-Drug Conjugate Induces Ovarian Tumor Regression in Preclinical Models

Although WNT signaling is frequently dysregulated in solid tumors, drugging this pathway has been challenging due to off-tumor effects. Current clinical pan-WNT inhibitors are nonspecific and lead to adverse effects, highlighting the urgent need for more specific WNT pathway-targeting strategies. We identified elevated expression of the WNT receptor Frizzled class receptor 7 (FZD7) in multiple solid cancers in The Cancer Genome Atlas, particularly in the mesenchymal and proliferative subtypes of ovarian serous cystadenocarcinoma, which correlate with poorer median patient survival. Moreover, we observed increased FZD7 protein expression in ovarian tumors compared with normal ovarian tissue, indicating that FZD7 may be a tumor-specific antigen. We therefore developed a novel antibody-drug conjugate, septuximab vedotin (F7-ADC), which is composed of a chimeric human-mouse antibody to human FZD7 conjugated to the microtubule-inhibiting drug monomethyl auristatin E (MMAE). F7-ADC selectively binds human FZD7, potently kills ovarian cancer cells in vitro, and induces regression of ovarian tumor xenografts in murine models. To evaluate F7-ADC toxicity in vivo, we generated mice harboring a modified Fzd7 gene where the resulting Fzd7 protein is reactive with the human-targeting F7-ADC. F7-ADC treatment of these mice did not induce acute toxicities, indicating a potentially favorable safety profile in patients. Overall, our data suggest that the antibody-drug conjugate approach may be a powerful strategy to combat FZD7-expressing ovarian cancers in the clinic.

Cancer stem cells: a major culprit of intra-tumor heterogeneity

Cancer is recognized as a preeminent factor of the world's mortality. Although various modalities have been designed to cure this life-threatening ailment, a significant impediment in the effective output of cancer treatment is heterogeneity. Cancer is characterized as a heterogeneous health disorder that comprises a distinct group of transformed cells to assist anomalous proliferation of affected cells. Cancer stem cells (CSCs) are a leading cause of cancer heterogeneity that is continually transformed by cellular extrinsic and intrinsic factors. They intensify neoplastic cells aggressiveness by strengthening their dissemination, relapse and therapy resistance. Considering this viewpoint, in this review article we have discussed some intrinsic (transcription factors, cell signaling pathways, genetic alterations, epigenetic modifications, non-coding RNAs (ncRNAs) and epitranscriptomics) and extrinsic factors (tumor microenvironment (TME)) that contribute to CSC heterogeneity and plasticity, which may help scientists to meddle these processes and eventually improve cancer research and management. Besides, the potential role of CSCs heterogeneity in establishing metastasis and therapy resistance has been articulated which signifies the importance of developing novel anticancer therapies to target CSCs along with targeting bulk tumor mass to achieve an effective output.

Unlocking the Wnt pathway: Therapeutic potential of selective targeting FZD7 in cancer

The Wnt signaling is of paramount pathophysiological importance. Despite showing promising anticancer activities in pre-clinical studies, current Wnt pathway inhibitors face complications in clinical trials resulting from on-target toxicity. Hence, the targeting of pathway component(s) that are essential for cancer but dispensable for normal physiology is key to the development of a safe Wnt signaling inhibitor. Frizzled₇ (FZD₇) is a Wnt pathway receptor that is redundant in healthy tissues but crucial in various cancers. FZD₇ modulates diverse aspects of carcinogenesis, including cancer growth, metastasis, maintenance of cancer stem cells, and chemoresistance. In this review, we describe state-of-the-art knowledge of the functions of FZD₇ in carcinogenesis and adult tissue homeostasis. Next, we overview the development of small molecules and biomolecules that target FZD₇. Finally, we discuss challenges and possibilities in developing FZD₇-selective antagonists.

Drug discovery efforts toward inhibitors of canonical Wnt/β-catenin signaling pathway in the treatment of cancer: A composition-of-matter review (2010-2020)

The Wnt/β-catenin pathway has a crucial role in the proliferation and differentiation of normal cells as well as the self-renewal and pluripotency of stem cells, including cancer stem cells (CSCs). Targeting this pathway with small-molecule chemotherapeutics, discovered via conventional efforts, has proved difficult. Recently, computer-aided drug discovery efforts have produced promising chemotherapeutics. A concerted effort to develop inhibitors of this pathway through more efficient and cost-effective drug discovery methods could lead to a significant increase in clinically relevant therapeutics. Herein, patents from 2010 to 2020 are reviewed to identify those that have disclosed composition of matter for small-molecule inhibitors of the Wnt/ β-catenin pathway for cancer. We believe that such efforts will provide insights for future therapeutic candidate discovery and development in this field.

Context Matters-Why We Need to Change From a One Size Fits all Approach to Made-to-Measure Therapies for Individual Patients With Pancreatic Cancer

Pancreatic cancer is one of the deadliest cancers and remains a major unsolved health problem. While pancreatic ductal adenocarcinoma (PDAC) is associated with driver mutations in only four major genes (KRAS, TP53, SMAD4, and CDKN2A), every tumor differs in its molecular landscape, histology, and prognosis. It is crucial to understand and consider these differences to be able to tailor treatment regimens specific to the vulnerabilities of the individual tumor to enhance patient outcome. This review focuses on the heterogeneity of pancreatic tumor cells and how in addition to genetic alterations, the subsequent dysregulation of multiple signaling cascades at various levels, epigenetic and metabolic factors contribute to the oncogenesis of PDAC and compensate for each other in driving cancer progression if one is tackled by a therapeutic approach. This implicates that besides the need for new combinatorial therapies for PDAC, a personalized approach for treating this highly complex cancer is required. A strategy that combines both a target-based and phenotypic approach to identify an effective treatment, like Reverse Clinical Engineering® using patient-derived organoids, is discussed as a promising way forward in the field of personalized medicine to tackle this deadly disease.

WNT/β-Catenin Pathway in Soft Tissue Sarcomas: New Therapeutic Opportunities?

Simple Summary

The WNT/β-catenin signaling pathway is involved in fundamental processes for the proliferation and differentiation of mesenchymal stem cells. However, little is known about its relevance for mesenchymal neoplasms, such us soft tissue sarcomas (STS). Chemotherapy based on doxorubicin (DXR) still remains the standard first-line treatment for locally advanced unresectable or metastatic STS, although overall survival could not be improved by combination with other chemotherapeutics. In this sense, the development of new therapeutic approaches continues to be an unmatched goal. This review covers the most important molecular alterations of the WNT signaling pathway in STS, broadening the current knowledge about STS as well as identifying novel drug targets. Furthermore, the current therapeutic options and drug candidates to modulate WNT signaling, which are usually classified by their interaction site upstream or downstream of β-catenin, and their presumable clinical impact on STS are discussed.

Abstract

Soft tissue sarcomas (STS) are a very heterogeneous group of rare tumors, comprising more than 50 different histological subtypes that originate from mesenchymal tissue. Despite their heterogeneity, chemotherapy based on doxorubicin (DXR) has been in use for forty years now and remains the standard first-line treatment for locally advanced unresectable or metastatic STS, although overall survival could not be improved by combination with other chemotherapeutics. In this sense, the development of new therapeutic approaches continues to be a largely unmatched goal. The WNT/β-catenin signaling pathway is involved in various fundamental processes for embryogenic development, including the proliferation and differentiation of mesenchymal stem cells. Although the role of this pathway has been widely researched in neoplasms of epithelial origin, little is known about its relevance for mesenchymal neoplasms. This review covers the most important molecular alterations of the WNT signaling pathway in STS. The detection of these alterations and the understanding of their functional consequences for those pathways controlling sarcomagenesis development and progression are crucial to broaden the current knowledge about STS as well as to identify novel drug targets. In this regard, the current therapeutic options and drug candidates to modulate WNT signaling, which are usually classified by their interaction site upstream or downstream of β-catenin, and their presumable clinical impact on STS are also discussed.

Macrophages and cancer stem cells: a malevolent alliance

Myeloid cells infiltrating tumors are gaining ever growing attention in the last years because their pro-tumor and immunosuppressive functions are relevant for disease progression and therapeutic responses. The functional ambiguity of tumor-associated macrophages (TAMs), mostly promoting tumor evolution, is a challenging hurdle. This is even more evident in the case of cancer stem cells (CSCs); as active participants in the specialized environment of the cancer stem cell niche, TAMs initiate a reciprocal conversation with CSCs. TAMs contribute to protect CSCs from the hostile environment (exogenous insults, toxic compounds, attacks from the immune cells), and produce several biologically active mediators that modulate crucial developmental pathways that sustain cancer cell stemness. In this review, we have focused our attention on the interaction between TAMs and CSCs; we describe how TAMs impact on CSC biology and, in turn, how CSCs exploit the tissue trophic activity of macrophages to survive and progress. Since CSCs are responsible for therapy resistance and tumor recurrence, they are important therapeutic targets. In view of the recent success in oncology obtained by stimulating the immune system, we discuss some macrophage-targeted therapeutic strategies that may also affect the CSCs and interrupt their malevolent alliance.

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

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