Oncogenic Signaling Networks Research Articles

Hypoxia-Inducible Factor 1-Alpha (HIF-1α) and Cancer: Mechanisms of Tumor Hypoxia and Therapeutic Targeting.

Hypoxia-inducible factor 1-alpha (HIF-1α) is necessary for cells to adapt to low oxygen levels often present in the tumor microenvironment. HIF-1α triggers a transcriptional program that promotes invasion, angiogenesis, metabolic reprogramming, and cell survival when it is active in hypoxic environments. These processes together lead to the growth and spread of tumors. This review article examines the molecular mechanisms by which HIF-1α contributes to tumor progression, including its regulation by oxygen-dependent and independent pathways, interactions with oncogenic signaling networks, and impact on the tumor microenvironment. Additionally, we explore current therapeutic strategies targeting HIF-1α, such as small molecule inhibitors, RNA interference, and immunotherapy approaches. Understanding the multifaceted roles of HIF-1α in cancer biology not only elucidates the complexities of tumor hypoxia but also opens avenues for developing novel and more effective cancer therapies.

Cancer signaling, cell/gene therapy, diagnosis and role of nanobiomaterials

An important characteristic of cancer is aberrant metabolism. Drug resistance, cancer stem cells, metastasis and tumorigenesis are all significantly impacted by abnormal cancer metabolism, which includes enhanced anabolic pathways and aerobic glycolysis. The Hippo pathway, Myc and PI3K/AKT are recognized oncogenic signaling networks that control the expression of metabolic genes and increase the level of activity of metabolic enzymes. On the other hand, abnormal metabolic pathways result in disruptions to the internal signal transduction pathways of cells, providing energy, building blocks and redox capabilities necessary for uncontrolled cancer cell proliferation. Studies and clinical trials are being carried out to investigate the impact of minute substances or dietary modifications, such as calorie restriction, fasting and intermittent fasting, on the inhibition of metabolic enzymes. The metabolic phenotypes of malignancies are remarkably diverse, much like genetic variability. Genetic abnormalities and a variety of signals found in the tumor microenvironment contribute to this variability. Therefore, one of the main objectives of contemporary cancer therapies is to overcome metabolic plasticity. This overview explains the relationships between biochemical and pathways of signaling and emphasizes recent research on the metabolic properties of cancer. We also present fresh justifications for the upcoming class of medications that target cancer metabolism. This is an overview of our latest studies on the progress of nanomedicine and disease detection at the tiny level of nano-bio interactions between biological systems and nanoparticles. Significant progress in the field of nanomedicine has been accomplished in the last 20 years. However, the absence of a thorough knowledge of nano-bio interactions in the clinical situation makes it difficult to significantly improve overall patient survival with nanomedicine.

Abstract LB028: Discovery and characterization of selective heterobifunctional degraders of EP300 in hematopoietic malignancies

Abstract The paralogous histone acetyltransferases EP300 and CREBBP are two of the master regulators of transcription by controlling both enhancer and promoter activity through histone and non-histone acetylation. EP300 and CREBBP activity is primarily driven by their acetylation of K27 and K18 on histone H3 leading to open and active chromatin state. Targeting the EP300/CREBBP axis of chromatin regulation may be a way to disrupt the signaling pathways downstream of key oncogenic signaling networks like MYC/IRF4 in hematopoietic cancers. Successful development of dual EP300/CREBBP BRDi and HATi has led to promising pre-clinical efficacy, but due to observed tolerability issues may potentially limit their utility in the clinic. We hypothesized, based upon published mouse KO phenotypes, that a selective EP300 compound may improve tolerability. Due to the high sequence homology between EP300 and CREBBP in both the BRD and HAT domains, developing selective inhibitors has proven to be challenging. To combat this, we have utilized heterobifunctional protein degrader technology (ProDegs, also known as PROTACS) to develop EP300 selective ProDegs with greater than 100-fold selectivity over CREBBP. We observe rapid targeted degradation of EP300 with maximal degradation occurring within the first 2-4 hours after treatment. Concomitant with the loss of EP300, we see modulation of the associated H3K27ac and H3K18ac biomarkers as well as alterations in key oncogenic transcription networks. In both in vitro and in vivo assays looking at impact to platelet maturation, we observed that selective loss of EP300 largely abrogated observed thrombocytopenia compared to dual EP300/CREBBP inhibitors. Upon treatment, MM and NHL models show strong downregulation of MYC/IRF4 oncogenic signaling pathways, both of which culminate in a loss of cellular viability and cell death. Additionally, we observe in vivo dose responsive tumor growth inhibition in OPM2 and Pfeiffer xenograft models. Together, the data demonstrate the potential utility of EP300 selective ProDegs for the treatment of hematopoietic malignancies. Citation Format: Frederick A. Derheimer, Ninvita Givarkes, Natalie Miller, Rita Grantner, Casey Quinlan, Sonja Brun, Thomas Paul, Astrid Ruefli-Brasse, Stefan Steyn, Derek Bartlett, Matthew Hayward, Matthew Brown, Daniel Uccello, Benjamin J. Burke, Kris Borzilleri, Adam Gilbert, Michelle Hemkens. Discovery and characterization of selective heterobifunctional degraders of EP300 in hematopoietic malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB028.

Abstract 1675: Investigating the role of SRC-family kinases in MPNST tumorigenesis

Abstract Purpose: Malignant peripheral nerve sheath tumor (MPNST), an aggressive soft-tissue sarcoma, is the leading cause of mortality in patients with neurofibromatosis type 1. Over the past two decades, significant advancement has been made in understanding the pathogenesis of MPNST. Still, this progress has not improved overall survival of patients. Therefore, ongoing efforts to identify alterations contributing to the transformation, progression, and metastasis of MPNST are essential for pinpointing targetable oncogenic signaling pathways for this cancer. Previous studies have revealed an increase in YAP/TAZ activity through both LATS1/2-dependent and LATS1/2-independent mechanisms, suggesting that YAP/TAZ hyperactivity may act as a convergence point for MPNST pathogenesis. YES and SRC, two members of the SRC-family kinases (SFKs), were shown to phosphorylate LATS1/2 and YAP/TAZ, and stimulate the transcriptional activity of YAP/TAZ by promoting their nuclear accumulation in hepatocellular carcinoma and colorectal cancer cells. Thus, we have investigated whether YES and SRC are involved in the pathogenesis of MPNSTs. Experimental Design: To assess whether the SFK-YAP/TAZ signaling axis is implicated in the development of MPNST, we have used genetic and pharmacological approaches to investigate the roles of YES and SRC in the proliferation of a subset of human MPNST cell lines, and in the growth of xenografted MPNST tumors in ectopic and orthotopic mouse models. We also performed a phosphoproteome and a transcriptome analysis of YES and SRC-depleted MPNST cells to assess their oncogenic signaling network. Lastly, we evaluated the clinical significance of phospho-SFK and YAP in human MPNST TMAs. Results: Our findings reveal that YES and SRC activity play an essential and redundant role in sustaining the proliferation of human MPNST cell lines. Further, the simultaneous depletion of both kinases impedes tumor growth in xenograft MPNST mouse models. Transcriptomic analyses identified YAP and TAZ as potential effectors of SFKs, as well as other family of transcription factors. Finally, TMA data suggested a correlation between the expressions of YAP, YAP/TAZ, and phospho-SFK and the progression of MPNST. Citation Format: Elamine Zereg, Laure Voisin, Karl Grenier, Mathieu Courcelles, Sungmi Jung, Pierre Thibault, Sylvain Meloche. Investigating the role of SRC-family kinases in MPNST tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1675.

Abstract 7545: Epigenetic plasticity in rewiring DNMT1/UHRF1-RB1- NFkB signaling circuit regulates asbestos-induced mesothelial malignant transformation

Abstract The exact mechanisms underlying the causal relationship between asbestos exposure and malignant mesothelioma (MM) have yet to be elucidated. Widespread genomic and epigenomic alterations are being implicated in rewiring of oncogenic signaling networks which may contribute to initiation and progression of MM. In the present study, we examined the molecular profiles of mesothelial cells exposed to asbestos in-vitro and found that asbestos-induced activation of DNMT1/UHRF1 mediated epigenetic repression of RB1 in normal mesothelial cells as well as mesothelioma cells via promoter-specific methylation mechanisms. RB1, as a noncanonical transcription factor, was capable of also negatively modulating the transcriptional activities of DNMT1/UHRF1 mesothelium and mesothelioma. Functioning as one of the downstream effectors of RB1, NFkB was also involved in the transcriptional regulation of DNMT1/UHRF1 directly in a promoter-selective manner and played a pivotal role in the acute as well as chronic functional and phenotypic changes of mesothelial cells following asbestos exposure. Pharmacological interference of the dysregulated RB1-DNMT1/UHRF1- RB1-NFkB signaling circuit constitutively arrested the invasive growth of MPM cells. In-vivo studies using FVB genetic background wild-type and Bap1+/- mice further revealed involvement of epigenetically dysregulation of the RB1-DNMT1/UHRF1- RB1-NFkB signaling circuit during asbestos-induced malignant transformation of mesothelial cells. Taken together, our data are the first to describe that asbestos epigenetically rewires the RB1-DNMT1/UHRF1- RB1-NFkB signaling circuit during mesothelioma development and suggest potential novel strategies to reverse these epigenetic perturbations for MPM treatment in the clinic. Citation Format: Sichuan Xi, Xinwei Wu, David M Straughan, Eden C Payabyab, Haitao Wang, Ruihong Wang, Mary Zhang, Shamus R. Carr, Chuong D. Hoang, David S. Schrump. Epigenetic plasticity in rewiring DNMT1/UHRF1-RB1- NFkB signaling circuit regulates asbestos-induced mesothelial malignant transformation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7545.

Abstract IA021: Digital patient avatars predict cancer evolution and personalised therapeutic strategies

Abstract Tumour heterogeneity manifested by genetic diversity and interchangeable cell states poses considerable challenges for the design of therapeutic strategies to combat cancer. While many strategies have been proposed to address this problem, using combination treatments and sequential delivery of therapies, the scope of combinations and sequencing order of therapies is enormous and is beyond the capacity of exhaustive testing through experimental models. We therefore propose using computational models to rapidly identify effective therapeutic interventions supported by convincing mechanistic explanations. Digital cancer avatars are computational programs representing oncogenic signalling networks and mapping molecular interactions to cell phenotype, which can be interrogated in silico. These computational programs specify how molecular interactions and perturbations produce cellular responses, such as cell proliferation, cell survival or cell death, and as such are well-suited to provide novel mechanistic insights into cellular behaviours as well as to identify therapeutic strategies for targeting them. In this talk, I will demonstrate the utility of bespoke computational models for triple-negative breast cancer, non-small cell lung cancer and melanoma to study how genomic changes drive tumour evolution and therapeutic response, and how these models are used to identify personalised combination treatments to overcome resistance. I will also present an in silico method applied to these models, to screen tens of millions combinations for effective sequential treatments by mapping the evolution of a tumour in response to a single-agent treatment and determining the optimal second-line treatment that will overcome resistance. Together these studies demonstrate the utility of digital avatars to improve our understanding of the mechanisms driving tumour progression and pave the way for personalised therapeutic strategies for improved cancer patient outcomes. Citation Format: Jasmin Fisher. Digital patient avatars predict cancer evolution and personalised therapeutic strategies [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Translating Cancer Evolution and Data Science: The Next Frontier; 2023 Dec 3-6; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_2):Abstract nr IA021.

Abstract A099: Utilising interactomics to uncover oncogenic KRAS signalling networks in the context of the tumor microenvironment

Abstract Extensive genetic analyses of Pancreatic Ductal Adenocarcinoma (PDAC) tumors have identified the GTPase KRAS as a major driver of tumorigenesis, with over 90% of tumors possessing oncogenic KRAS mutations, primarily at the mutational hotspot G12. KRAS G12 mutants are constitutively active, and promote cancer growth by hyperdriving multiple downstream effector pathways via direct physical interactions with proteins such as PI3K and RAF. Despite KRASG12Mut being a promising drug target, direct targeting of KRASG12Mut or downstream pathways has shown limited success, with the emergence of rapid resistance. This resistance is associated with compensatory rewiring of parallel pathways, and the emergence of drug-resistant mutations. Further, the failure to translate these therapies into the clinic maybe due to the inability of many preclinical models to incorporate the contribution of the tumor microenvironment (TME). Approaches to study KRAS signalling in complex multicellular environments have often relied on techniques such as transcriptomics that utilise inference to determine signalling dynamics rather than the direct contribution of KRAS to these outputs. Further, these approaches are often unable to determine cell-type specific signalling. A promising methodology to capture cell-specific KRAS signalling in a heterocellular setting is proximity labelling. This technique involves the engineering of cell lines to express a KRASG12Mut transgene fused to a promiscuous biotin ligase (TurboID). The KRASG12Mut-TurboID fusion is capable of labelling proximal proteins within a radius of ~10 nm with a biotin tag. Biotinylated proteins can be isolated and identified using mass spectrometry. As the labelling radius is narrow, with a short labelling time, this approach is ideal for cell-type specific signalling network analysis. Utilising a novel three-dimensional hydrogel scaffold mimicking the human tumor microenvironment, we are characterising the interactomes of KRASG12Mut across a library of patient derived organoids (hPDOs) grown in co-cultures with stromal cells using proximity labelling. Initial characterisation of KRASG12Mut interactomes in a cohort of 10 hPDOs grown in monoculture has highlighted a high degree of diversity among interactors and pathway activation, independent of the type of KRAS mutation. Specifically, unique patterns of interactions were observed in PI3K, mTOR and MAPK pathway components. Further, co-culture of hPDOs with stromal cells, such as fibroblasts and myeloid cells, yields differential engagement of KRAS interactors when compared to hPDOs grown in monoculture indicative of a role for the TME in shaping KRAS signalling. Current work is ongoing to determine the effect of KRAS targeting therapies on adaptive pathway rewiring using this approach. Interrogation of these interactomes has the potential to uncover resistance mechanisms that emerge in response to KRAS pathway inhibition, and identify novel targets for combinatorial therapy for future studies and clinical trials for pancreatic cancer patients. Citation Format: Nasir A. Haider, Joanna Kelly, Duncan Smith, Claus Jorgensen. Utilising interactomics to uncover oncogenic KRAS signalling networks in the context of the tumor microenvironment [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr A099.

Cellular Plasticity in Mammary Gland Development and Breast Cancer

Cellular plasticity is a phenomenon where cells adopt different identities during development and tissue homeostasis as a response to physiological and pathological conditions. This review provides a general introduction to processes by which cells change their identity as well as the current definition of cellular plasticity in the field of mammary gland biology. Following a synopsis of the evolving model of the hierarchical development of mammary epithelial cell lineages, we discuss changes in cell identity during normal mammary gland development with particular emphasis on the effect of the gestation cycle on the emergence of new cellular states. Next, we summarize known mechanisms that promote the plasticity of epithelial lineages in the normal mammary gland and highlight the importance of the microenvironment and extracellular matrix. A discourse of cellular reprogramming during the early stages of mammary tumorigenesis that follows focuses on the origin of basal-like breast cancers from luminal progenitors and oncogenic signaling networks that orchestrate diverse developmental trajectories of transforming epithelial cells. In addition to the epithelial-to-mesenchymal transition, we highlight events of cellular reprogramming during breast cancer progression in the context of intrinsic molecular subtype switching and the genesis of the claudin-low breast cancer subtype, which represents the far end of the spectrum of epithelial cell plasticity. In the final section, we will discuss recent advances in the design of genetically engineered models to gain insight into the dynamic processes that promote cellular plasticity during mammary gland development and tumorigenesis in vivo.

Identification of Balanol As a Potential Inhibitor of PAK1 That Induces Apoptosis and Cytoprotective Autophagy in Colorectal Cancer Cells.

Colorectal cancer (CRC) is a common malignancy of the gastrointestinal tract, often accompanied by poor prognosis and high incidence and mortality. p21 activated kinases (PAKs) have been used as therapeutic targets because of their central role in many oncogenic signaling networks. By exploring tumor databases, we found that PAK1 overexpression is associated with poor prognosis in colorectal cancer, and therefore, PAK1-targeted inhibition is a new potential therapeutic strategy for colorectal cancer. We identified that Balanol (compound 6, DB04098) can effectively target PAK1 by high-throughput virtual screening. In vitro, compound 6 exhibited favorable PAK1 inhibition with potent anti-proliferative and anti-migration activity in SW480 cells. Additionally, we also found that compound 6 induced apoptosis and cytoprotective autophagy in SW480 cells. Together, these results indicate that compound 6 is a potential novel PAK1 inhibitor, which would be utilized as a candidate compound for future CRC treatment.

Abstract 3936: ALK fusion oncogene driven SERPINB4 expression enhances tumor survival in NSCLC

Abstract Anaplastic lymphoma kinase (ALK) fusion variants in non-small-cell-lung cancer (NSCLC) consist of numerous dimerising fusion partners, with the most common being EML4. Clinical data suggests that the degree of treatment benefit in response to ALK tyrosine kinase inhibitors (TKIs) differs among the variant present in the patient tumor. Therefore, a better understanding the oncogenic signaling networks driven by different ALK-fusion variants is important. Here, we developed highly controlled doxycycline-inducible cell models bearing four different ALK fusion proteins, namely EML4-ALK-V1, EML4-ALK-V3, KIF5B-ALK, and TFG-ALK, in the context of non-tumorigenic NL20 human bronchial epithelial cells. These were complimented by patient-derived NSCLC cell lines harboring either EML4-ALK-V1 or EML4-ALK-V3 fusions. RNA-seq and phosphoproteomics analysis were employed to identify dysregulated genes and hyper/hypo-phosphorylated proteins associated with ALK fusion expression. Among ALK fusion induced responses, we noted a robust inflammatory signature that included up-regulation of the Serpin B4 serine protease inhibitor in both NL20-inducible cell models and ALK-positive NSCLC patient-derived cell lines. We show that STAT3 is a major transcriptional regulator of SERPINB4 downstream of ALK fusions, along with NF-kB and AP1. The upregulation of SERPINB4 promotes survival of ALK fusion expressing cells and inhibits natural killer (NK) cell-mediated cytotoxicity. In conclusion, our study reveals a novel ALK downstream survival axis that regulates Serpin B4 expression and identifies a molecular target that has potential for therapeutic impact targeting the immune response together with ALK TKIs in NSCLC. Citation Format: Tzu-Po Chuang, Wei-Yun Lai, Jonatan L. Gabre, Dan E. Lind, Ganesh Umapathy, Abdulmalik A. Bokhari, Bengt Bergman, Linnea Kristenson, Fredrik B. Thorén, Anh Le, Robert Doebele, Jimmy V. Eynden, Ruth H. Palmer, Bengt Hallberg. ALK fusion oncogene driven SERPINB4 expression enhances tumor survival in NSCLC. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3936.

ALK fusion NSCLC oncogenes promote survival and inhibit NK cell responses via SERPINB4 expression

Anaplastic lymphoma kinase (ALK) fusion variants in Non-Small Cell Lung Cancer (NSCLC) consist of numerous dimerizing fusion partners. Retrospective investigations suggest that treatment benefit in response to ALK tyrosine kinase inhibitors (TKIs) differs dependent on the fusion variant present in the patient tumor. Therefore, understanding the oncogenic signaling networks driven by different ALK fusion variants is important. To do this, we developed controlled inducible cell models expressing either Echinoderm Microtubule Associated Protein Like 4 (EML4)-ALK-V1, EML4-ALK-V3, Kinesin Family Member 5B (KIF5B)-ALK, or TRK-fused gene (TFG)-ALK and investigated their transcriptomic and proteomic responses to ALK activity modulation together with patient-derived ALK-positive NSCLC cell lines. This allowed identification of both common and isoform-specific responses downstream of these four ALK fusions. An inflammatory signature that included upregulation of the Serpin B4 serine protease inhibitor was observed in both ALK fusion inducible and patient-derived cells. We show that Signal transducer and activator of transcription 3 (STAT3), Nuclear Factor Kappa B (NF-κB) and Activator protein 1 (AP1) are major transcriptional regulators of SERPINB4 downstream of ALK fusions. Upregulation of SERPINB4 promotes survival and inhibits natural killer cell-mediated cytotoxicity, which has potential for therapeutic impact targeting the immune response together with ALK TKIs in NSCLC.

Lactate-related metabolic reprogramming and immune regulation in colorectal cancer.

Changes in cellular metabolism involving fuel sources are well-known mechanisms of cancer cell differentiation in the context of carcinogenesis. Metabolic reprogramming is regulated by oncogenic signaling and transcriptional networks and has been identified as an essential component of malignant transformation. Hypoxic and acidified tumor microenvironment contributes mainly to the production of glycolytic products known as lactate. Mounting evidence suggests that lactate in the tumor microenvironment of colorectal cancer(CRC) contributes to cancer therapeutic resistance and metastasis. The contents related to the regulatory effects of lactate on metabolism, immune response, and intercellular communication in the tumor microenvironment of CRC are also constantly updated. Here we summarize the latest studies about the pleiotropic effects of lactate in CRC and the clinical value of targeting lactate metabolism as treatment. Different effects of lactate on various immune cell types, microenvironment characteristics, and pathophysiological processes have also emerged. Potential specific therapeutic targeting of CRC lactate metabolism is also discussed. With increased knowledge, effective druggable targets might be identified, with the aim of improving treatment outcomes by reducing chemoresistance.

Abstract IA003: SC144 and the next generation IL6/GP130/STAT3 inhibitors for cancer prevention

Abstract IL6/GP130/STAT3 signaling plays a crucial role in multiple diseases, and all components of this signaling cascade are directly or indirectly implicated in tumorigenesis. Therefore, blockade of this signaling axis is expected to provide novel therapeutic opportunities to treat various diseases including cancer. IL6 binds to IL6R and GP130 to activate downstream signaling pathways to promote proliferation, survival and metastasis of cancer cells, and to stimulate angiogenesis on endothelial cells. Although GP130 is positioned at the junction of this oncogenic signaling network and is essential for activation of the network, there are no small-molecule inhibitors of GP130 under clinical development. Previously, we identified SC144 as a first-in-class, efficacious, safe, and orally active inhibitor of GP130. SC144 selectively inhibits the activation of downstream signaling pathways induced by GP130 ligands (IL6, LIF), with no significant effects on the activation by non-GP130 ligands, such as IFN-γ, SDF-1α, and PDGF. SC144 exhibits cytotoxicity in a panel of platinum-sensitive and platinum-resistant cells, with no significant cytotoxicity to human normal epithelial cells. In mouse xenograft models, SC144 significantly inhibited tumor growth through GP130 inhibition and induction of necrosis in the tumor. No toxicity was evident in normal tissues. Furthermore, SC144 showed significant in vivo efficacy in immune competent syngeneic mouse models. Unfortunately, clinical development of SC144 was delayed due to its poor solubility and metabolic instability. During the past two years, we have identified metabolic liabilities of SC144 and have undertaken an extensive medicinal chemistry lead optimization campaign to produce analogs with increased solubility and metabolic stability. The new analogs show favorable properties in single- and repeat-dosing pharmacokinetic (PK) studies. As a result, we have in hand a series of 2nd-generation analogs that are orally active, water-soluble, and display desirable PK properties suitable for advanced preclinical studies to support IND filing. Citation Format: Nouri Neamati. SC144 and the next generation IL6/GP130/STAT3 inhibitors for cancer prevention [abstract]. In: Proceedings of the Second Biennial NCI Meeting: Translational Advances in Cancer Prevention Agent Development (TACPAD); 2022 Sep 7-9. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_2): Abstract nr IA003.

Nimbolide, a Neem Limonoid, Inhibits Angiogenesis in Breast Cancer by Abrogating Aldose Reductase Mediated IGF-1/PI3K/Akt Signalling.

The insulin/IGF-1R/PI3K/Akt signalling cascade is increasingly being linked to breast cancer development, with aldose reductase (AR) playing a key role in mediating the crosstalk between this pathway and angiogenesis. The current study was designed to investigate whether nimbolide, a neem limonoid, targets the oncogenic signaling network to prevent angiogenesis in breast cancer. Breast cancer cells (MCF-7, MDA-MB-231), EAhy926 endothelial cells, MDA-MB-231 xenografted nude mice, and tumour tissues from breast cancer patients were used for the study. The expression of AR and key players in IGF-1/PI3K/Akt signaling and angiogenesis was evaluated by qRT-PCR, immunoblotting, and immunohistochemistry. Molecular docking and simulation, overexpression, and knockdown experiments were performed to determine whether nimbolide targets AR and IGF-1R. Nimbolide inhibited AR with consequent blockade of the IGF-1/PI3K/Akt and /HIF-1alpha/VEGF signalling circuit by influencing the phosphorylation and intracellular localisation of key signaling molecules. The downregulation of DNMT-1, HDAC-6, miR-21, HOTAIR, and H19 with the upregulation of miR-148a/miR-152 indicated that nimbolide regulates AR and IGF-1/PI3K/Akt signaling via epigenetic modifications. Coadministration of nimbolide with metformin and the chemotherapeutic drugs tamoxifen/cisplatin displayed higher efficacy than single agents in inhibiting IGF-1/PI3K/Akt/AR signaling. Grade-wise increases in IGF-1R and AR expression in breast cancer tissues underscore their value as biomarkers of progression. This study provides evidence for the anticancer effects of nimbolide in cellular and mouse models of breast cancer besides providing leads for new drug combinations. It has also opened up avenues for investigating potential molecules such as AR for therapeutic targeting of cancer.

Patient-level proteomic network prediction by explainable artificial intelligence

Understanding the pathological properties of dysregulated protein networks in individual patients’ tumors is the basis for precision therapy. Functional experiments are commonly used, but cover only parts of the oncogenic signaling networks, whereas methods that reconstruct networks from omics data usually only predict average network features across tumors. Here, we show that the explainable AI method layer-wise relevance propagation (LRP) can infer protein interaction networks for individual patients from proteomic profiling data. LRP reconstructs average and individual interaction networks with an AUC of 0.99 and 0.93, respectively, and outperforms state-of-the-art network prediction methods for individual tumors. Using data from The Cancer Proteome Atlas, we identify known and potentially novel oncogenic network features, among which some are cancer-type specific and show only minor variation among patients, while others are present across certain tumor types but differ among individual patients. Our approach may therefore support predictive diagnostics in precision oncology by inferring “patient-level” oncogenic mechanisms.

The Targeting of Noncoding RNAs by Quercetin in Cancer Prevention and Therapy.

The dietary flavonoid quercetin is ubiquitously distributed in fruits, vegetables, and medicinal herbs. Quercetin has been a focal point in recent years due to its versatile health-promoting benefits and high pharmacological values. It has well documented that quercetin exerts anticancer actions by inhibiting cell proliferation, inducing apoptosis, and retarding the invasion and metastasis of cancer cells. However, the exact mechanism of quercetin-mediated cancer chemoprevention is still not fully understood. With the advances in high-throughput sequencing technologies, the intricate oncogenic signaling networks have been gradually characterized. Increasing evidence on the close association between noncoding RNA (ncRNAs) and cancer etiopathogenesis emphasizes the potential of ncRNAs as promising molecular targets for cancer treatment. Available experimental studies indicate that quercetin can dominate multiple cancer-associated ncRNAs, hence repressing carcinogenesis and cancer development. Thus, modulation of ncRNAs serves as a key mechanism responsible for the anticancer effects of quercetin. In this review, we focus on the chemopreventive effects of quercetin on cancer pathogenesis by targeting cancer-relevant ncRNAs, supporting the viewpoint that quercetin holds promise as a drug candidate for cancer chemoprevention and chemotherapy. An in-depth comprehension of the interplay between quercetin and ncRNAs in the inhibition of cancer development and progression will raise the possibility of developing this bioactive compound as an anticancer agent that could be highly efficacious and safe in clinical practice.

Impact of anesthetics on oncogenic signaling network: a review on propofol and isoflurane.

Propofol as an intravenous anesthetic and isoflurane as an inhalational/volatile anesthetic continue to be an important part of surgical anesthetic interventions worldwide. The impact of these anesthetics on tumor progression, immune modulation, and survival rates of cancer patients has been widely investigated. Although most of the preclinical studies have provided a beneficial effect of propofol over isoflurane or other volatile anesthetics, several investigations have shown contradictory results, which warrant more preclinical and clinical studies. Propofol mostly exhibits antitumor properties, whereas isoflurane being a cost-effective anesthetic is frequently used. However, isoflurane has been also reported with protumorigenic activity. This review provides an overall perspective on the network of signaling pathways that may modulate several steps of tumor progression from inflammation, immunomodulation, epithelial-mesenchymal transition (EMT) to invasion, metastasis, angiogenesis, and cancer stemness and extracellular vesicles along with chemotherapeutic applications and clinical status of these anesthetics. A clear understanding of the mechanistic viewpoints of these anesthetics may pave the way for more prospective clinical trials with the ultimate goal of obtaining a safe and optimal anesthetic intervention that would prevent cancer recurrence and may influence better postoperative survival.

PFKFB4 Overexpression Facilitates Proliferation by Promoting the G1/S Transition and Is Associated with a Poor Prognosis in Triple-Negative Breast Cancer.

Background 6-Phosphofructo-2-kinase/fructose-2,6-biphosphate-4 (PFKFB4) is a key factor that plays an important role in tumorigenesis. However, its role in triple-negative breast cancer (TNBC) progression needs to be further validated. We investigated whether PFKFB4 is directly involved in the oncogenic signaling networks of TNBC. Methods First, we assessed the expression level of PFKFB4 in tumor tissue specimens by immunohistochemistry and evaluated its prognostic value. Next, the effect of PFKFB4 on TNBC cell growth and associated mechanisms were investigated. Finally, the results were further verified in vivo. Results We found that PFKFB4 overexpression was associated with an unfavorable prognosis in TNBC patients. PFKFB4 was overexpressed in TNBC cell lines in hypoxic environments, and its overexpression promoted tumor progression in vitro and in vivo. Further analyses demonstrated that the possible mechanism might be that PFKFB4 overexpression facilitates TNBC progression by enhancing the G1/S phase transition by increasing the protein level of CDK6 and phosphorylation of Rb. Conclusions These data suggest that PFKFB4 plays significant roles in the tumorigenesis and development of TNBC.

Nimbolide, a Neem Limonoid, Is a Promising Candidate for the Anticancer Drug Arsenal.

Nimbolide, a major limonoid constituent of Azadirachta indica, commonly known as neem, has attracted increasing research attention owing to its wide spectrum of pharmacological properties, predominantly anticancer activity. Nimbolide is reported to exert potent antiproliferative effects on a myriad cancer cell lines and chemotherapeutic efficacy in preclinical animal tumor models. The potentiality of nimbolide to circumvent multidrug resistance and aid in targeted protein degradation broaden its utility in enhancing therapeutic modalities and outcome. Accumulating evidence indicates that nimbolide prevents the acquisition of cancer hallmarks such as sustained proliferation, apoptosis evasion, invasion, angiogenesis, metastasis, and inflammation by modulating kinase-driven oncogenic signaling networks. Nimbolide has been demonstrated to abrogate aberrant activation of cellular signaling by influencing the subcellular localization of transcription factors and phosphorylation of kinases in addition to influencing the epigenome. Nimbolide, with its ever-expanding repertoire of molecular targets, is a valuable addition to the anticancer drug arsenal.

Clinical Potential of Kinase Inhibitors in Combination with Immune Checkpoint Inhibitors for the Treatment of Solid Tumors.

Oncogenic kinases contribute to immunosuppression and modulate the tumor microenvironment in solid tumors. Increasing evidence supports the fundamental role of oncogenic kinase signaling networks in coordinating immunosuppressive tumor microenvironments. This has led to numerous studies examining the efficacy of kinase inhibitors in inducing anti-tumor immune responses by increasing tumor immunogenicity. Kinase inhibitors are the second most common FDA-approved group of drugs that are deployed for cancer treatment. With few exceptions, they inevitably lead to intrinsic and/or acquired resistance, particularly in patients with metastatic disease when used as a monotherapy. On the other hand, cancer immunotherapies, including immune checkpoint inhibitors, have revolutionized cancer treatment for malignancies such as melanoma and lung cancer. However, key hurdles remain to successfully incorporate such therapies in the treatment of other solid cancers. Here, we review the recent literature on oncogenic kinases that regulate tumor immunogenicity, immune suppression, and anti-tumor immunity. Furthermore, we discuss current efforts in clinical trials that combine kinase inhibitors and immune checkpoint inhibitors to treat breast cancer and other solid tumors.