Inducing and exploiting vulnerabilities for the treatment of liver cancer

LncRNA MBNL1-AS1 knockdown increases the sensitivity of hepatocellular carcinoma to tripterine by regulating miR-708-5p-mediated glycolysis

Hepatocellular carcinoma (HCC) is identified as a common cancer type across the world and needs novel and efficient treatment. Tripterine, a well-known compound, exerts suppressive role in HCC development. However, the related molecular mechanism of tripterine in HCC remains unclear. The expression of MBNL1-AS1in HCC tissues and cells was measured via qRT-PCR assay. MTT assay was employed to estimate cell viability. Besides, cell migration as well as invasion was determined through transwell assay. Additionally, the binding ability of miR-708-5p and MBNL1-AS1or HK2 was proved by starBase database and luciferase reporter gene assay. Moreover, the HK2 level was detected by immunoblotting. MBNL1-AS1 was reduced in HCC tissues and cells. Overexpression of MBNL1-AS1 decreased the sensitivity of HCC cells to tripterine while MBNL1-AS1 silence played opposite effect. In addition, miR-708-5p was the target of MBNL1-AS1 and was down-regulated through MBNL1-AS1 in HCC cells. Moreover, miR-708-5p suppressed glycolysis rate and reduced the expression of vital glycolytic enzyme (HK2, LDHA and PKM2) in HCC cells. Furthermore, miR-708-5p reduced HK2 expression by binding to it directly. In this investigation, we proved that LncRNA MBNL1-AS1 increased the tripterine resistance of HCC cells at least partly by mediating miR-708-5p-related glycolysis. These findings revealed a potent therapeutic target for the treatment of HCC.

Inflammasome protein scaffolds the DNA damage complex during tumor development

Inflammasome sensors activate cellular signaling machineries to drive inflammation and cell death processes. Inflammasomes also control the development of certain diseases independently of canonical functions. Here, we show that the inflammasome protein NLR family CARD domain-containing protein 4 (NLRC4) attenuated the development of tumors in the Apcmin/+ mouse model. This response was independent of inflammasome signaling by NLRP3, NLRP6, NLR family apoptosis inhibitory proteins, absent in melanoma 2, apoptosis-associated speck-like protein containing a caspase recruitment domain, caspase-1 and caspase-11. NLRC4 interacted with the DNA-damage-sensing ataxia telangiectasia and Rad3-related (ATR)-ATR-interacting protein (ATRIP)-Ewing tumor-associated antigen 1 (ETAA1) complex to promote the recruitment of the checkpoint adapter protein claspin, licensing the activation of the kinase checkpoint kinase-1 (CHK1). Genotoxicity-induced activation of the NLRC4-ATR-ATRIP-ETAA1 complex drove the tumor-suppressing DNA damage response and CHK1 activation, and further attenuated the accumulation of DNA damage. These findings demonstrate a noninflammatory function of an inflammasome protein in promoting the DNA damage response and mediating protection against cancer.

Promise and challenges of traditional Chinese medicine, specifically Calculus bovis, in liver cancer treatment

Liver cancer, one of the most common malignancies worldwide, ranks sixth in incidence and third in mortality. Liver cancer treatment options are diverse, including surgical resection, liver transplantation, percutaneous ablation, transarterial chemoembolization, radiotherapy, chemotherapy, targeted therapy, immunotherapy, and traditional Chinese medicine (TCM). A multidisciplinary team (MDT) is essential to customize treatment plans based on tumor staging, liver function, and performance status (PS), ensuring individualized patient care. Treatment decisions require a MDT to tailor strategies based on tumor staging, liver function, and PS, ensuring personalized care. The approval of new first-line and second-line drugs and the establishment of standard treatments based on immune checkpoint inhibitors have significantly expanded treatment options for advanced liver cancer, improving overall prognosis. However, many patients do not respond effectively to these treatments and ultimately succumb to the disease. Modern oncology treatments, while extending patient survival, often come with severe side effects, resistance, and damage to the body, negatively impacting quality of life. Huang et al's study published at World Journal of Gastroenterology rigorously validates the anticancer properties of Calculus bovis, enhancing our understanding of TCM and contributing to new liver cancer treatment strategies. For over 5000 years, TCM has been used in East Asian countries like China to treat various diseases, including liver conditions. Analysis of real-world clinical data suggests that for patients with advanced-stage tumors lacking effective treatments, integrated TCM therapies could provide significant breakthroughs.

SSRI antidepressant citalopram reverses the Warburg effect to inhibit hepatocellular carcinoma by directly targeting GLUT1

Selective serotonin reuptake inhibitors (SSRIs) have shown promise in cancer therapy, particularly for hepatocellular carcinoma (HCC), but their molecular targets and mechanisms remain unclear. Here, we show that SSRIs exhibit significant anti-HCC effects independent of their classical target, the serotonin reuptake transporter (SERT). Using global inverse gene expression profiling, drug affinity responsive target stability assays, and in silico molecular docking, we demonstrate that citalopram targets glucose transporter 1 (GLUT1), resulting in reduced glycolytic flux. A mutant GLUT1 variant at the citalopram binding site (E380) diminishes the drug's inhibitory effects on the Warburg effect and tumor growth. In preclinical models, citalopram dampens the growth of GLUT1high liver tumors and displays a synergistic effect with anti-PD-1 therapy. Retrospective analysis reveals that SSRI use correlates with a lower risk of metastasis among patients with HCC. Our study describes a role for SSRIs in cancer metabolism, establishing a rationale for their repurposing as potential anti-cancer drugs for HCC.

Pan-cancer characterization of cellular senescence reveals its inter-tumor heterogeneity associated with the tumor microenvironment and prognosis

Cellular senescence (CS) is characterized by the irreversible cell cycle arrest and plays a key role in aging and diseases, such as cancer. Recent years have witnessed the burgeoning exploration of the intricate relationship between CS and cancer, with CS recognized as either a suppressing or promoting factor and officially acknowledged as one of the 14 cancer hallmarks. However, a comprehensive characterization remains absent from elucidating the divergences of this relationship across different cancer types and its involvement in the multi-facets of tumor development. Here we systematically assessed the cellular senescence of over 10,000 tumor samples from 33 cancer types, starting by defining a set of cancer-associated CS signatures and deriving a quantitative metric representing the CS status, called CS score. We then investigated the CS heterogeneity and its intricate relationship with the prognosis, immune infiltration, and therapeutic responses across different cancers. As a result, cellular senescence demonstrated two distinct prognostic groups: the protective group with eleven cancers, such as LIHC, and the risky group with four cancers, including STAD. Subsequent in-depth investigations between these two groups unveiled the potential molecular and cellular mechanisms underlying the distinct effects of cellular senescence, involving the divergent activation of specific pathways and variances in immune cell infiltrations. These results were further supported by the disparate associations of CS status with the responses to immuno- and chemo-therapies observed between the two groups. Overall, our study offers a deeper understanding of inter-tumor heterogeneity of cellular senescence associated with the tumor microenvironment and cancer prognosis.

Facile engineering of aptamer-coupled silk fibroin encapsulated myogenic gold nanocomposites: investigation of antiproliferative activity and apoptosis induction

Nanocomposites selectively induce cancer cell death, holding potential for precise liver cancer treatment breakthroughs. This study assessed the cytotoxicity of gold nanocomposites (Au NCs) enclosed within silk fibroin (SF), aptamer (Ap), and the myogenic Talaromyces purpureogenus (TP) against a human liver cancer cell (HepG2). The ultimate product, Ap-SF-TP@Au NCs, results from a three-step process. This process involves the myogenic synthesis of TP@Au NCs derived from TP mycelial extract, encapsulation of SF on TP@Au NCs (SF-TP@Au NCs), and the conjugation of Ap within SF-TP@Au NCs. The synthesized NCs are analyzed by various characteristic techniques. Ap-SF-TP@Au NCs induced potential cell death in HepG2 cells but exhibited no cytotoxicity in non-cancerous cells (NIH3T3). The morphological changes in cells were examined through various biochemical staining methods. Thus, Ap-SF-TP@Au NCs emerge as a promising nanocomposite for treating diverse cancer cells.

Cancer drug-tolerant persister cells: from biological questions to clinical opportunities

The emergence of drug resistance is the most substantial challenge to the effectiveness of anticancer therapies. Orthogonal approaches have revealed that a subset of cells, known as drug-tolerant 'persister' (DTP) cells, have a prominent role in drug resistance. Although long recognized in bacterial populations which have acquired resistance to antibiotics, the presence of DTPs in various cancer types has come to light only in the past two decades, yet several aspects of their biology remain enigmatic. Here, we delve into the biological characteristics of DTPs and explore potential strategies for tracking and targeting them. Recent findings suggest that DTPs exhibit remarkable plasticity, being capable of transitioning between different cellular states, resulting in distinct DTP phenotypes within a single tumour. However, defining the biological features of DTPs has been challenging, partly due to the complex interplay between clonal dynamics and tissue-specific factors influencing their phenotype. Moreover, the interactions between DTPs and the tumour microenvironment, including their potential to evade immune surveillance, remain to be discovered. Finally, the mechanisms underlying DTP-derived drug resistance and their correlation with clinical outcomes remain poorly understood. This Roadmap aims to provide a comprehensive overview of the field of DTPs, encompassing past achievements and current endeavours in elucidating their biology. We also discuss the prospect of future advancements in technologies in helping to unveil the features of DTPs and propose novel therapeutic strategies that could lead to their eradication.

Disrupting YAP1-mediated glutamine metabolism induces synthetic lethality alongside ODC1 inhibition in osteosarcoma

PURPOSE

Osteosarcoma, a highly malignant primary bone tumor primarily affecting adolescents, frequently develops resistance to initial chemotherapy, leading to metastasis and limited treatment options. Our study aims to uncover novel therapeutic targets for metastatic and recurrent osteosarcoma.

METHODS

In this study, we proved the potential of modulating the YAP1-regulated glutamine metabolic pathway to augment the response of OS to DFMO. We initially employed single-cell transcriptomic data to gauge the activation level of polyamine metabolism in MTAP-deleted OS patients. This was further substantiated by transcriptome sequencing data from recurrent and non-recurrent patient tissues, confirming the activation of polyamine metabolism in progressive OS. Through high-throughput drug screening, we pinpointed CIL56, a YAP1 inhibitor, as a promising candidate for a combined therapeutic strategy with DFMO. In vivo, we utilized PDX and CDX models to validate the therapeutic efficacy of this drug combination. In vitro, we conducted western blot analysis, qPCR analysis, immunofluorescence staining, and PuMA experiments to monitor alterations in molecular expression, distribution, and tumor metastasis capability. We employed CCK-8 and colony formation assays to assess the proliferative capacity of cells in the experimental group. We used flow cytometry and reactive oxygen probes to observe changes in ROS and glutamine metabolism within the cells. Finally, we applied RNA-seq in tandem with metabolomics to identify metabolic alterations in OS cells treated with a DFMO and CIL56 combination. This enabled us to intervene and validate the role of the YAP1-mediated glutamine metabolic pathway in DFMO resistance.

RESULTS

Through single-cell RNA-seq data analysis, we pinpointed a subset of late-stage OS cells with significantly upregulated polyamine metabolism. This upregulation was further substantiated by transcriptomic profiling of recurrent and non-recurrent OS tissues. High-throughput drug screening revealed a promising combination strategy involving DFMO and CIL56. DFMO treatment curbs the phosphorylation of YAP1 protein in OS cells, promoting nuclear entry and initiating the YAP1-mediated glutamine metabolic pathway. This reduces intracellular ROS levels, countering DFMO's anticancer effect. The therapeutic efficacy of DFMO can be amplified both in vivo and in vitro by combining it with the YAP1 inhibitor CIL56 or the glutaminase inhibitor CB-839. This underscores the significant potential of targeting the YAP1-mediated glutamine metabolic pathway to enhance efficacy of DFMO.

CONCLUSION

Our findings elucidate YAP1-mediated glutamine metabolism as a crucial bypass mechanism against DFMO, following the inhibition of polyamine metabolism. Our study provides valuable insights into the potential role of DFMO in an "One-two Punch" therapy of metastatic and recurrent osteosarcoma.

Tryptanthrin targets GSTP1 to induce senescence and increases the susceptibility to apoptosis by senolytics in liver cancer cells

Targeting senescence has emerged as a promising strategy for liver cancer treatment. However, the lack of a safe agent capable of inducing complete senescence and being combined with senolytics poses a limitation. Here, we screened a natural product library and identified tryptanthrin (TRYP) as a potent inducer of cellular senescence in liver cancer cells both in vitro and in vivo. Mechanistically, Glutathione S-transferase P1 (GSTP1), a key regulator for redox homeostasis, was identified as a target protein for TRYP-induced senescence. TRYP directly bound to GSTP1 and inhibited its enzymatic activity, mediating reactive oxygen species (ROS) accumulation, followed by DNA damage response (DDR), consequently contributing to initiating primary senescence. Furthermore, TRYP triggered DNA damage-dependent activation of NF-κB pathway, which evoked senescence-associated secretory phenotype (SASP), thereby leading to senescence reinforcement. Importantly, TRYP exposed the vulnerability of tumor cells and sensitized senescent cells to apoptosis induced by senolytic agent ABT263, a Bcl2 inhibitor. Taken together, our findings reveal that TRYP induces cellular senescence via GSTP1/ROS/DDR/NF-κB/SASP axis, providing a novel potential application in synergizing with senolytic therapy in liver cancer.

Diversified applications of hepatocellular carcinoma medications: molecular-targeted, immunotherapeutic, and combined approaches

Hepatocellular carcinoma (HCC) is one of the primary forms of liver cancer and is currently the sixth most prevalent malignancy worldwide. In addition to surgical interventions, effective drug treatment is essential for treating HCC. With an increasing number of therapeutic drugs for liver cancer undergoing clinical studies, the therapeutic strategies for advanced HCC are more diverse than ever, leading to improved prospects for HCC patients. Molecular targeted drugs and immunotherapies have become crucial treatment options for HCC. Treatment programs include single-agent molecular-targeted drugs, immunotherapies, combinations of immunotherapies with molecular-targeted drugs, and dual immune checkpoint inhibitors. However, further exploration is necessary to determine the optimal pharmacological treatment regimens, and the development of new effective drugs is urgently needed. This review provides an overview of the current globally approved drugs for liver cancer, as well as the latest advances in ongoing clinical research and drug therapies. Additionally, the review offers an outlook and discussion on the prospects for the development of drug therapy approaches for HCC.

Senolytic effect of triterpenoid complex from Ganoderma lucidum on adriamycin-induced senescent human hepatocellular carcinoma cells model in vitro and in vivo

Background

Ganoderma lucidum (G. lucidum) is a famous medicinal mushroom that has been reported to prevent and treat a variety of diseases. Different extractions from G. lucidum have been used to manage age-related diseases, including cancer. Nevertheless, the senolytic activity of G. lucidum against senescent cancer cells has not been investigated. Although cellular senescence causes tumor growth inhibition, senescent cells promote the growth of the neighboring tumor cells through paracrine effects. Therefore, the elimination of senescent cells is a new strategy for cancer treatment.

Methods

In this study, senescence was triggered in HCC cells by the chemotherapeutic agent Adriamycin (ADR), and subsequently, cells were treated with TC to assess its senolytic activity.

Results

We found for the first time that the triterpenoid complex (TC) from G. lucidum had senolytic effect, which could selectively eliminate adriamycin (ADR)-induced senescent cells (SCs) of hepatocellular carcinoma (HCC) cells via caspase-dependent and mitochondrial pathways-mediated apoptosis and reduce the levels of senescence markers, thereby inhibiting the progression of cancers caused by SCs. TC could block autophagy at the late stage in SCs, resulting in a significant activation of TC-induced apoptosis. Furthermore, TC inhibited the senescence-associated secretory phenotype (SASP) in SCs through the inhibition of NF-κB, TFEB, P38, ERK, and mTOR signaling pathways and reducing the number of SCs. Sequential administration of ADR and TC in vivo significantly reduced tumor growth and reversed the toxicity of ADR.

Conclusion

A triterpenoid complex isolated from G. lucidum may serve as a novel senolytic agent against SCs, and its combination with chemotherapeutic agents may enhance their antitumor efficacy.

The paradox of senescent-marker positive cancer cells: challenges and opportunities

Senescence is an anti-tumour mechanism and hallmark of cancer. Loss or mutation of key senescence effectors, such as p16INK4A, are frequently observed in cancer. Intriguingly, some human tumours are both proliferative and senescent-marker positive (Sen-Mark+). Here, we explore this paradox, focusing on the prognostic consequences and the current challenges in classifying these cells. We discuss future strategies for Sen-Mark+ cell detection together with emerging opportunities to exploit senescence for cancer.

The dual role of cellular senescence in human tumor progression and therapy

Cellular senescence, one of the hallmarks of cancer, is characterized by cell cycle arrest and the loss of most normal cellular functions while acquiring a hypersecretory, proinflammatory phenotype. The function of senescent cells in cancer cells varies depending on the cellular conditions. Before the occurrence of cancer, senescent cells act as a barrier to prevent its development. But once cancer has occurred, senescent cells play a procancer role. However, few of the current studies have adequately explained the diversity of cellular senescence across cancers. Herein, we concluded the latest intrinsic mechanisms of cellular senescence in detail and emphasized the senescence-associated secretory phenotype as a key contributor to heterogeneity of senescent cells in tumor. We also discussed five kinds of inducers of cellular senescence and the advancement of senolytics in cancer, which are drugs that tend to clear senescent cells. Finally, we summarized the various effects of senescent cells in different cancers and manifested that their functions may be diametrically opposed under different circumstances. In short, this paper contributes to the understanding of the diversity of cellular senescence in cancers and provides novel insight for tumor therapy.

Cellular senescence and metabolic reprogramming: Unraveling the intricate crosstalk in the immunosuppressive tumor microenvironment

The intrinsic oncogenic mechanisms and properties of the tumor microenvironment (TME) have been extensively investigated. Primary features of the TME include metabolic reprogramming, hypoxia, chronic inflammation, and tumor immunosuppression. Previous studies suggest that senescence-associated secretory phenotypes that mediate intercellular information exchange play a role in the dynamic evolution of the TME. Specifically, hypoxic adaptation, metabolic dysregulation, and phenotypic shifts in immune cells regulated by cellular senescence synergistically contribute to the development of an immunosuppressive microenvironment and chronic inflammation, thereby promoting the progression of tumor events. This review provides a comprehensive summary of the processes by which cellular senescence regulates the dynamic evolution of the tumor-adapted TME, with focus on the complex mechanisms underlying the relationship between senescence and changes in the biological functions of tumor cells. The available findings suggest that components of the TME collectively contribute to the progression of tumor events. The potential applications and challenges of targeted cellular senescence-based and combination therapies in clinical settings are further discussed within the context of advancing cellular senescence-related research.

Nutrient-delivery and metabolism reactivation therapy for melanoma

To fulfil the demands of rapid proliferation, tumour cells undergo significant metabolic alterations. Suppression of hyperactivated metabolism has been proven to counteract tumour growth. However, whether the reactivation of downregulated metabolic pathways has therapeutic effects remains unexplored. Here we report a nutrient-based metabolic reactivation strategy for effective melanoma treatment. L-Tyrosine-oleylamine nanomicelles (MTyr-OANPs) were constructed for targeted supplementation of tyrosine to reactivate melanogenesis in melanoma cells. We found that reactivation of melanogenesis using MTyr-OANPs significantly impeded the proliferation of melanoma cells, primarily through the inhibition of glycolysis. Furthermore, leveraging melanin as a natural photothermal reagent for photothermal therapy, we demonstrated the complete eradication of tumours in B16F10 melanoma-bearing mice through treatment with MTyr-OANPs and photothermal therapy. Our strategy for metabolism activation-based tumour treatment suggests specific nutrients as potent activators of metabolic pathways.

Integrated machine learning screened glutamine metabolism-associated biomarker SLC1A5 to predict immunotherapy response in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) stands as one of the most prevalent malignancies. While PD-1 immune checkpoint inhibitors have demonstrated promising therapeutic efficacy in HCC, not all patients exhibit a favorable response to these treatments. Glutamine is a crucial immune cell regulatory factor, and tumor cells exhibit glutamine dependence. In this study, HCC patients were divided into two subtypes (C1 and C2) based on glutamine metabolism-related genes via consensus clustering. The C1 pattern, in contrast to C2, was associated with a lower survival probability among HCC patients. Additionally, the C1 pattern exhibited higher proportions of patients with advanced tumor stages. The activity of C1 in glutamine metabolism and transport is significantly enhanced, while its oxidative phosphorylation activity is reduced. And, C1 was mainly involved in the progression-related pathway of HCC. Furthermore, C1 exhibited high levels of immunosuppressive cells, cytokine-receptor interactions and immune checkpoint genes, suggesting C1 as an immunosuppressive subtype. After stepwise selection based on integrated four machine learning methods, SLC1A5 was finally identified as the pivotal gene that distinguishes the subtypes. The expression of SLC1A5 was significantly positively correlated with immunosuppressive status. SLC1A5 showed the most significant correlation with macrophage infiltration, and this correlation was confirmed through the RNA-seq data of CLCA project and our cohort. Low-SLC1A5-expression samples had better immunogenicity and responsiveness to immunotherapy. As expected, SubMap and survival analysis indicated that individuals with low SLC1A5 expression were more responsive to anti-PD1 therapy. Collectively, this study categorized HCC patients based on glutamine metabolism-related genes and proposed two subclasses with different clinical traits, biological behavior, and immune status. Machine learning was utilized to identify the hub gene SLC1A5 for HCC classification, which also could predict immunotherapy response.

Sorafenib-mediated cleavage of p62 initiates cellular senescence as a mechanism to evade its anti-hepatocellular carcinoma efficacy

Hepatocellular carcinoma (HCC) stands as one of the most aggressively advancing and lethal malignancies. Sorafenib is presently endorsed as a primary therapy for advanced liver cancer, but its resistance presents a formidable challenge. Previous studies have implicated a connection between post-sorafenib discontinuation rebound and the development of drug resistance, yet the underlying mechanism remains elusive. In this study, we discerned that Sorafenib induced a senescent phenotype in HCC cells and caused a cleavage of ubiquitin-binding protein p62. Mechanistic studies establish that truncated p62 drives cellular senescence by promoting proteasome-dependent degradation of 4EBP1. Furthermore, truncated p62 induced specific ubiquitination of 4EBP1. Crucially, virtual drug screening uncovered that dacinostat inhibited cellular senescence by blocking sorafenib-induced p62 cleavage. In summary, our findings imply that truncated p62 from sorafenib cleavage promotes senescence via 4EBP1 degradation. The prevention of p62 cleavage could emerge as a crucial strategy for impeding the sorafenib-induced cellular senescence.

CDK4/6 inhibitor PD-0332991 suppresses hepatocarcinogenesis by inducing senescence of hepatic tumor-initiating cells

INTRODUCTION

Owing to the limited treatment options for hepatocellular carcinoma (HCC), interventions targeting pre-HCC stages have attracted increasing attention. In the pre-HCC stage, hepatic tumor-initiating cells (hTICs) proliferate abnormally and contribute to hepatocarcinogenesis. Numerous studies have investigated targeted senescence induction as an HCC intervention. However, it remains to be clarified whether senescence induction of hTICs could serve as a pre-HCC intervention.

OBJECTIVES

This study was designed to investigate whether senescence induction of hTICs in the precancerous stage inhibit HCC initiation.

METHODS AND RESULTS

HCC models developed from chronic liver injury (CLI) were established by using Fah-/- mice and N-Ras + AKT mice. PD-0332991, a selective CDK4/6 inhibitor that blocks the G1/S transition in proliferating cells, was used to induce senescence during the pre-HCC stage. Upon administration of PD-0332991, we observed a significant reduction in HCC incidence following selective senescence induction in hTICs, and an alleviation liver injury in the CLI-HCC models. PD-0332991 also induced senescence in vitro in cultured hTICs isolated from CLI-HCC models. Moreover, RNA sequencing (RNA-seq) analysis delineated that the "Cyclin D-CDK4/6-INK4-Rb" pathway was activated in both mouse and human liver samples during the pre-HCC stage, while PD-0332991 exhibited substantial inhibition of this pathway, thereby inducing cellular senescence in hTICs. Regarding the immune microenvironment, we demonstrated that senescent hTICs secrete key senescence-associated secretory phenotypic (SASP) factors, CXCL10 and CCL2, to activate and recruit macrophages, and contribute to immune surveillance.

CONCLUSION

We found that hTICs can be targeted and induced into a senescent state during the pre-HCC stage. The SASP factors released by senescent hTICs further activate the immune response, facilitating the clearance of hTICs, and consequently suppressing HCC occurrence. We highlight the importance of pre-HCC interventions and propose that senescence-inducing drugs hold promise for preventing HCC initiation under CLI.

Guidelines for minimal information on cellular senescence experimentation in vivo

Cellular senescence is a cell fate triggered in response to stress and is characterized by stable cell-cycle arrest and a hypersecretory state. It has diverse biological roles, ranging from tissue repair to chronic disease. The development of new tools to study senescence in vivo has paved the way for uncovering its physiological and pathological roles and testing senescent cells as a therapeutic target. However, the lack of specific and broadly applicable markers makes it difficult to identify and characterize senescent cells in tissues and living organisms. To address this, we provide practical guidelines called "minimum information for cellular senescence experimentation in vivo" (MICSE). It presents an overview of senescence markers in rodent tissues, transgenic models, non-mammalian systems, human tissues, and tumors and their use in the identification and specification of senescent cells. These guidelines provide a uniform, state-of-the-art, and accessible toolset to improve our understanding of cellular senescence in vivo.

Therapy-Induced Senescence: Novel Approaches for Markers Identification

Therapy-induced senescence (TIS) represents a major cellular response to anticancer treatments. Both malignant and non-malignant cells in the tumor microenvironment undergo TIS and may be harmful for cancer patients since TIS cells develop a senescence-associated secretory phenotype (SASP) that can sustain tumor growth. The SASP also modulates anti-tumor immunity, although the immune populations involved and the final results appear to be context-dependent. In addition, senescent cancer cells are able to evade senescence growth arrest and to resume proliferation, likely contributing to relapse. So, research data suggest that TIS induction negatively affects therapy outcomes in cancer patients. In line with this, new interventions aimed at the removal of senescent cells or the reprogramming of their SASP, called senotherapy, have become attractive therapeutic options. To date, the lack of reliable, cost-effective, and easy-to-use TIS biomarkers hinders the application of recent anti-senescence therapeutic approaches in the clinic. Hence, the identification of biomarkers for the detection of TIS tumor cells and TIS non-neoplastic cells is a high priority in cancer research. In this review article, we describe the current knowledge about TIS, outline critical gaps in our knowledge, and address recent advances and novel approaches for the discovery of TIS biomarkers.

Androgen deprivation-induced senescence confers sensitivity to a senolytic strategy in prostate cancer

We have previously demonstrated that androgen-dependent prostate cancer (PCa) cell lines enter a state of senescence following exposure to androgen deprivation therapies (ADT). ADT-induced senescence was found to be transient, as senescent cells develop castration resistance and re-emerge into a proliferative state even under continuous androgen deprivation in vitro. Moreover, the BCL-XL/BCL-2 inhibitor, ABT-263 (navitoclax), an established senolytic agent, promoted apoptosis of senescent PCa cells, suppressing proliferative recovery and subsequent tumor cell outgrowth. As this strategy has not previously been validated in vivo, we used a clinically relevant, syngeneic murine model of PCa, where mice were either castrated or castrated followed by the administration of ABT-263. Our results largely confirm the outcomes previously reported in vitro; specifically, castration alone results in a transient tumor growth suppression with characteristics of senescence, which is prolonged by exposure to ABT-263. Most critically, mice that underwent castration followed by ABT-263 experienced a statistically significant prolongation in survival, with an increase of 14.5 days in median survival time (56 days castration alone vs. 70.5 days castration + ABT-263). However, as is often the case in studies combining the promotion of senescence with a senolytic (the "one-two" punch approach), the suppression of tumor growth by the inclusion of the senolytic agent was transient, allowing for tumor regrowth once the drug treatment was terminated. Nevertheless, the results of this work suggest that the "one-two" punch senolytic strategy in PCa may effectively interfere with, diminish, or delay the development of the lethal castration-resistant phenotype.

Therapy-Induced Cellular Senescence: Potentiating Tumor Elimination or Driving Cancer Resistance and Recurrence?

Cellular senescence has been increasingly recognized as a hallmark of cancer, reflecting its association with aging and inflammation, its role as a response to deregulated proliferation and oncogenic stress, and its induction by cancer therapies. While therapy-induced senescence (TIS) has been linked to resistance, recurrence, metastasis, and normal tissue toxicity, TIS also has the potential to enhance therapy response and stimulate anti-tumor immunity. In this review, we examine the Jekyll and Hyde nature of senescent cells (SnCs), focusing on how their persistence while expressing the senescence-associated secretory phenotype (SASP) modulates the tumor microenvironment through autocrine and paracrine mechanisms. Through the SASP, SnCs can mediate both resistance and response to cancer therapies. To fulfill the unmet potential of cancer immunotherapy, we consider how SnCs may influence tumor inflammation and serve as an antigen source to potentiate anti-tumor immune response. This new perspective suggests treatment approaches based on TIS to enhance immune checkpoint blockade. Finally, we describe strategies for mitigating the detrimental effects of senescence, such as modulating the SASP or targeting SnC persistence, which may enhance the overall benefits of cancer treatment.

A study on construction of a prognosis model for liver cancer based on analgesic targets and screening therapeutic drugs

BACKGROUND

Liver cancer is one of the most malignant liver diseases in the world, and the 5-year survival rate of such patients is low. Analgesics are often used to cure pain prevalent in liver cancer. The expression changes and clinical significance of the analgesic targets (ATs) in liver cancer have not been deeply understood.

OBJECTIVE

The purpose of this study is to clarify the expression pattern of ATs gene in liver cancer and its clinical significance. Through the comprehensive analysis of transcriptome data and clinical parameters, the prognosis model related to ATs gene is established, and the drug information sensitive to ATs is mined.

METHODS

The study primarily utilized transcriptomic data and clinical information from liver cancer patients sourced from The Cancer Genome Atlas (TCGA) database. These data were employed to analyze the expression of ATs, conduct survival analysis, gene set variation analysis (GSVA), immune cell infiltration analysis, establish a prognostic model, and perform other bioinformatic analyses. Additionally, data from liver cancer patients in the International Cancer Genome Consortium (ICGC) were utilized to validate the accuracy of the model. Furthermore, the impact of analgesics on key genes in the prognostic model was assessed using data from the Comparative Toxicogenomics Database (CTD).

RESULTS

The study investigated the differential expression of 58 ATs genes in liver cancer compared to normal tissues. Patients were stratified based on ATs expression, revealing varied survival outcomes. Functional enrichment analysis highlighted distinctions in spindle organization, centrosome, and spindle microtubule functions. Prognostic modeling identified low TP53 expression as protective, while elevated CCNA2, NEU1, and HTR2C levels posed risks. Commonly used analgesics, including acetaminophen and others, were found to influence the expression of these genes. These findings provide insights into potential therapeutic strategies for liver cancer and shed light on the molecular mechanisms underlying its progression.

CONCLUSIONS

The collective analysis of gene signatures associated with ATs suggests their potential as prognostic predictors in hepatocellular carcinoma patients. These findings not only offer insights into cancer therapy but also provide novel avenues for the development of indications for analgesics.

Cell senescence in liver diseases: pathological mechanism and theranostic opportunity

The liver is not oblivious to the passage of time, as ageing is a major risk factor for the development of acute and chronic liver diseases. Ageing produces alterations in all hepatic cells, affecting their phenotype and function and worsening the prognosis of liver disease. The ageing process also implies the accumulation of a cellular state characterized by a persistent proliferation arrest and a specific secretory phenotype named cellular senescence. Indeed, senescent cells have key roles in many physiological processes; however, their accumulation owing to ageing or pathological conditions contributes to the damage occurring in chronic diseases. The aim of this Review is to provide an updated description of the pathophysiological events in which hepatic senescent cells are involved and their role in liver disease progression. Finally, we discuss novel geroscience therapies that could be applied to prevent or improve liver diseases and age-mediated hepatic deregulations.

Senescence and senolysis in cancer: The latest findings

Aging is a life phenomenon that occurs in most living organisms and is a major risk factor for many diseases, including cancer. Cellular senescence is a cellular trait induced by various genomic and epigenetic stresses. Senescent cells are characterized by irreversible cell growth arrest and excessive secretion of inflammatory cytokines (senescence-associated secretory phenotypes, SASP). Chronic tissue microinflammation induced by SASP contributes to the pathogenesis of a variety of age-related diseases, including cancer. Senolysis is a promising new strategy to selectively eliminate senescent cells in order to suppress chronic inflammation, suggesting its potential use as an anticancer therapy. This review summarizes recent findings on the molecular basis of senescence in cancer cells and senolysis.

CDC7 inhibition drives an inflammatory response and a p53-dependent senescent-like state in breast epithelial cells

Drugs that block DNA replication prevent cell proliferation, which may result in anticancer activity. The latter is dependent on the drug's mode of action as well as on cell type-dependent responses to treatment. The inhibition of Cell division cycle 7-related protein kinase (CDC7), a key regulator of DNA replication, decreases the efficiency of origin firing and hampers the restarting of paused replication forks. Here, we show that upon prolonged CDC7 inhibition, breast-derived MCF10A cells progressively withdraw from the cell cycle and enter a reversible senescent-like state. This is characterised by the rewiring of the transcriptional programme with the induction of cytokine and chemokine expression and correlates with the accumulation of Cyclic GMP-AMP synthase (cGAS)-positive micronuclei. Importantly, cell fate depends on Cellular tumour antigen p53 (p53) function as cells no longer enter senescence but are funnelled into apoptosis upon p53 knockout. This work uncovers key features of the secondary response to CDC7 inhibitors, which could aid the development of these compounds as anticancer drugs.

Impact and potential value of immunosenescence on solid gastrointestinal tumors

Solid gastrointestinal tumors often respond poorly to immunotherapy for the complex tumor microenvironment (TME), which is exacerbated by immune system alterations. Immunosenescence is the process of increased diversification of immune genes due to aging and other factors, leading to a decrease in the recognition function of the immune system. This process involves immune organs, immune cells, and the senescence-associated secretory phenotype (SASP). The most fundamental change is DNA damage, resulting in TME remodeling. The main manifestations are worsening inflammation, increased immunosuppressive SASP production, decreased immune cell antitumor activity, and the accumulation of tumor-associated fibroblasts and myeloid-derived suppressor cells, making antitumor therapy less effective. Senotherapy strategies to remove senescent cells and block key senescence processes can have synergistic effects with other treatments. This review focuses on immunoenescence and its impact on the solid TME. We characterize the immunosenescent TME and discuss future directions for antitumor therapies targeting senescence.

A Platinum-Aluminum Bimetallic Salen Complex for Pro-senescence Cancer Therapy

Cell senescence is defined as irreversible cell cycle arrest, which can be triggered by telomere shortening or by various types of genotoxic stress. Induction of senescence is emerging as a new strategy for the treatment of cancer, especially when sequentially combined with a second senolytic drug capable of killing the resulting senescent cells, however severely suffering from the undesired off-target side effects from the senolytic drugs. Here, we prepare a bimetalic platinum-aluminum salen complex (Alumiplatin) for cancer therapy-a combination of pro-senesence chemotherapy with in situ senotherapy to avoid the side effects. The aluminum salen moiety, as a G-quadruplex stabilizer, enhances the salen's ability to induce cancer cell senescence and this phenotype is in turn sensitive to the cytotoxic activity of the monofunctional platinum moiety. It exhibits an excellent capability for inducing senescence, a potent cytotoxic activity against cancer cells both in vitro and in vivo, and an improved safety profile compared to cisplatin. Therefore, Alumiplatin may be a good candidate to be further developed into safe and effective anticancer agents. This novel combination of cell senescence inducers with genotoxic drugs revolutionizes the therapy options of designing multi-targeting anticancer agents to improve the efficacy of anticancer therapies.

Exosomal miRNA-146a-5p Derived from Senescent Hepatocellular Carcinoma Cells Promotes Aging and Inhibits Aerobic Glycolysis in Liver Cells via Targeting IRF7

Hepatocellular carcinoma (HCC) is a major global health challenge. Chemotherapy can cause HCC cells to become senescent. Senescent HCC cells play an important role in inhibiting or promoting cancer by producing extracellular vesicles with a senescence-associated secretory phenotype (EV-SASP). miRNA can be strongly upregulated in EV-SASP during the aging process and can substantially alter the phenotypic characteristics of cells. MiRNA microarray analysis revealed that miRNA-146a-5p was highly expressed in oxaliplatin- and H2O2-induced senescent Huh7 cells, and RT‒PCR confirmed its significant upregulation in exosomes. The transcriptome sequencing results of Huh7 cells overexpressing miRNA-146a-5p suggested that miRNA-146a-5p could regulate HCC cell glycolysis. Subsequently, a dual luciferase assay was used to verify whether miRNA-146a-5p can interact with IRF7 to promote aging. The key functions of miRNA-146a-5p and IRF7 in aerobic glycolysis in liver cancer cells were determined through experiments analyzing glucose uptake, lactate production, the oxygen consumption rate (OCR) and the proton efflux rate (PER). Subsequently, the regulatory effect of IRF7 on the key glycolytic gene PFKL was confirmed through luciferase reporter assays. The western blot experiment results showed that miR-146a-5p can activate CHK2 and p53 phosphorylated proteins by targeting IRF7, and upregulate p21 protein. Overexpression of miRNA-146a-5p effectively inhibited the aerobic glycolytic function of HCC cells. Moreover, silencing IRF7 effectively inhibited aerobic glycolysis. MiR-146a-5p. MiR-146a-5p can activate the phosphorylation of CHK2 phosphorylation protein and its downstream protein p53 by targeting IRF7, and the activated p53 upregulates the expression of p21. Our study revealed that exosomal miRNA-146a-5p produced by aging HCC cells, can inhibit HCC cell proliferation through inhibiting aerobic glycolysis and promote HCC cell aging by activating CHK2/p53/p21 signaling way by targeting IRF7.

Defining melanoma combination therapies that provide senolytic sensitivity in human melanoma cells

Malignant Melanoma that resists immunotherapy remains the deadliest form of skin cancer owing to poor clinically lasting responses. Alternative like genotoxic or targeted chemotherapy trigger various cancer cell fates after treatment including cell death and senescence. Senescent cells can be eliminated using senolytic drugs and we hypothesize that the targeted elimination of therapy-induced senescent melanoma cells could complement both conventional and immunotherapies. We utilized a panel of cells representing diverse mutational background relevant to melanoma and found that they developed distinct senescent phenotypes in response to treatment. A genotoxic combination therapy of carboplatin-paclitaxel or irradiation triggered a mixed response of cell death and senescence, irrespective of BRAF mutation profiles. DNA damage-induced senescent melanoma cells exhibited morphological changes, residual DNA damage, and increased senescence-associated secretory phenotype (SASP). In contrast, dual targeted inhibition of Braf and Mek triggered a different mixed cell fate response including senescent-like and persister cells. While persister cells could reproliferate, senescent-like cells were stably arrested, but without detectable DNA damage and senescence-associated secretory phenotype. To assess the sensitivity to senolytics we employed a novel real-time imaging-based death assay and observed that Bcl2/Bcl-XL inhibitors and piperlongumine were effective in promoting death of carboplatin-paclitaxel and irradiation-induced senescent melanoma cells, while the mixed persister cells and senescent-like cells resulting from Braf-Mek inhibition remained unresponsive. Interestingly, a direct synergy between Bcl2/Bcl-XL inhibitors and Braf-Mek inhibitors was observed when used out of the context of senescence. Overall, we highlight diverse hallmarks of melanoma senescent states and provide evidence of context-dependent senotherapeutics that could reduce treatment resistance while also discussing the limitations of this strategy in human melanoma cells.

Dual Inhibition of CDK4/6 and XPO1 Induces Senescence With Acquired Vulnerability to CRBN-Based PROTAC Drugs

BACKGROUND & AIMS

Despite the increasing number of treatment options available for liver cancer, only a small proportion of patients achieve long-term clinical benefits. Here, we aim to develop new therapeutic approaches for liver cancer.

METHODS

A compound screen was conducted to identify inhibitors that could synergistically induce senescence when combined with cyclin-dependent kinase (CDK) 4/6 inhibitor. The combination effects of CDK4/6 inhibitor and exportin 1 (XPO1) inhibitor on cellular senescence were investigated in a panel of human liver cancer cell lines and multiple liver cancer models. A senolytic drug screen was performed to identify drugs that selectively killed senescent liver cancer cells.

RESULTS

The combination of CDK4/6 inhibitor and XPO1 inhibitor synergistically induces senescence of liver cancer cells in vitro and in vivo. The XPO1 inhibitor acts by causing accumulation of RB1 in the nucleus, leading to decreased E2F signaling and promoting senescence induction by the CDK4/6 inhibitor. Through a senolytic drug screen, cereblon (CRBN)-based proteolysis targeting chimera (PROTAC) ARV-825 was identified as an agent that can selectively kill senescent liver cancer cells. Up-regulation of CRBN was a vulnerability of senescent liver cancer cells, making them sensitive to CRBN-based PROTAC drugs. Mechanistically, we find that ubiquitin specific peptidase 2 (USP2) directly interacts with CRBN, leading to the deubiquitination and stabilization of CRBN in senescent liver cancer cells.

CONCLUSIONS

Our study demonstrates a striking synergy in senescence induction of liver cancer cells through the combination of CDK4/6 inhibitor and XPO1 inhibitor. These findings also shed light on the molecular processes underlying the vulnerability of senescent liver cancer cells to CRBN-based PROTAC therapy.

Targeting cellular senescence as a therapeutic vulnerability in gastric cancer

AIMS

Cellular senescence (CS) represents an intracellular defense mechanism responding to stress signals and can be leveraged as a "vulnerability" in cancer treatment. This study aims to construct a CS atlas for gastric cancer (GC) and uncover potential therapeutics for GC patients.

MATERIALS AND METHODS

38 senescence-associated regulators with prognostic significance in GC were obtained from the CellAge database to construct Gastric cancer-specific Senescence Score (GSS). Using eXtreme Sum algorism, GSS-based drug repositioning was conducted to identify drugs that could antagonize GSS in CMap database. In vitro experiments were conducted to test the effect of combination of palbociclib and exisulind in eliminating GC cells.

KEY FINDINGS

Patients with high GSS exhibited CS-related features, such as CS markers upregulation, adverse clinical outcomes and hypomethylation status. scRNA-seq data showed malignant cells with high GSS exhibited enhanced senescence state and more immunosuppressive signals such as PVR-CD96 compared with malignant cells with low GSS. In addition, the GSS-High cancer associated fibroblasts might secrete cytokines and chemokines such as IL-6, CXCL1, CXCL12, and CCL2 to from an immunosuppressive microenvironment, and GSS could serve as an indicator for immunotherapy resistance. Exisulind exhibited the greatest potential to reverse GSS. In vitro experiments demonstrated that exisulind could induce apoptosis and suppress the proliferation of palbociclib-induced senescent GC cells.

SIGNIFICANCE

Overall, GSS offers a framework for better understanding of correlation between senescence and GC, which might provide new insights into the development of novel therapeutics in GC.

Network pharmacology prediction and experiment validation of anti-liver cancer activity of Curcumae Rhizoma and Hedyotis diffusa Willd

Objective

This study aims to elucidate anti-liver cancer components and potential mechanisms of Curcumae Rhizoma and Hedyotis diffusa Willd (CR-HDW).

Methods

Effective components and targets of CR-HDW were identified from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. Liver cancer-related genes were collected from GeneCards, Gene-Disease Association (DisGeNET), and National Center for Biotechnology Information (NCBI). Protein-protein interaction networks, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were conducted to analyze the identified genes. Molecular docking was used to simulate binding of the active components and their target proteins. Cell activity assay, western blot, and senescence-associated β-galactosidase (SA-β-gal) experiments were conducted to validate core targets identified from molecular docking.

Results

Ten active compounds of CR-HDW were identified including quercetin, 3-epioleanic acid and hederagenin. The primary core proteins comprised Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Protein Kinase B(AKT1), etc. The pathways for Phosphoinositide 3-kinase (PI3K)/ AKT, cellular senescence, Fork head boxO (FOXO) were revealed as important for anti-cancer activity of CR-HDW. Molecular docking demonstrated strong binding between liver cancer target proteins and major active components of CR-HDW. In-vitro experiments confirmed that hederagenin and 3-epioleolic acid inhibited HuH-7 cell growth, reduced expression of PI3K, AKT, and mechanistic target of rapamycin (mTOR) proteins. Hederagenin also induced HuH-7 senescence.

Conclusions

In summary, The authors' results suggest that the CR-HDW component (Hederagenin, 3-epoxy-olanolic acid) can inhibit the proliferation of HuH-7 cells by decreasing PI3K, AKT, and mTOR. Hederagenin also induced HuH-7 senescence.

Macrophages and tumor-associated macrophages in the senescent microenvironment: From immunosuppressive TME to targeted tumor therapy

In-depth studies of the tumor microenvironment (TME) have helped to elucidate its cancer-promoting mechanisms and inherent characteristics. Cellular senescence, which acts as a response to injury and can the release of senescence-associated secretory phenotypes (SASPs). These SASPs release various cytokines, chemokines, and growth factors, remodeling the TME. This continual development of a senescent environment could be associated with chronic inflammation and immunosuppressive TME. Additionally, SASPs could influence the phenotype and function of macrophages, leading to the recruitment of tumor-associated macrophages (TAMs). This contributes to tumor proliferation and metastasis in the senescent microenvironment, working in tandem with immune regulation, angiogenesis, and therapeutic resistance. This comprehensive review covers the evolving nature of the senescent microenvironment, macrophages, and TAMs in tumor development. We also explored the links between chronic inflammation, immunosuppressive TME, cellular senescence, and macrophages. Moreover, we compiled various tumor-specific treatment strategies centered on cellular senescence and the current challenges in cellular senescence research. This study aimed to clarify the mechanism of macrophages and the senescent microenvironment in tumor progression and advance the development of targeted tumor therapies.

Targeting senescent cells to reshape the tumor microenvironment and improve anticancer efficacy

Cancer is daunting pathology with remarkable breadth and scope, spanning genetics, epigenetics, proteomics, metalobomics and cell biology. Cellular senescence represents a stress-induced and essentially irreversible cell fate associated with aging and various age-related diseases, including malignancies. Senescent cells are characterized of morphologic alterations and metabolic reprogramming, and develop a highly active secretome termed as the senescence-associated secretory phenotype (SASP). Since the first discovery, senescence has been understood as an important barrier to tumor progression, as its induction in pre-neoplastic cells limits carcinogenesis. Paradoxically, senescent cells arising in the tumor microenvironment (TME) contribute to tumor progression, including augmented therapeutic resistance. In this article, we define typical forms of senescent cells commonly observed within the TME and how senescent cells functionally remodel their surrounding niche, affect immune responses and promote cancer evolution. Furthermore, we highlight the recently emerging pipelines of senotherapies particularly senolytics, which can selectively deplete senescent cells from affected organs in vivo and impede tumor progression by restoring therapeutic responses and securing anticancer efficacies. Together, co-targeting cancer cells and their normal but senescent counterparts in the TME holds the potential to achieve increased therapeutic benefits and restrained disease relapse in future clinical oncology.

Tumor biomarkers for diagnosis, prognosis and targeted therapy

Tumor biomarkers, the substances which are produced by tumors or the body's responses to tumors during tumorigenesis and progression, have been demonstrated to possess critical and encouraging value in screening and early diagnosis, prognosis prediction, recurrence detection, and therapeutic efficacy monitoring of cancers. Over the past decades, continuous progress has been made in exploring and discovering novel, sensitive, specific, and accurate tumor biomarkers, which has significantly promoted personalized medicine and improved the outcomes of cancer patients, especially advances in molecular biology technologies developed for the detection of tumor biomarkers. Herein, we summarize the discovery and development of tumor biomarkers, including the history of tumor biomarkers, the conventional and innovative technologies used for biomarker discovery and detection, the classification of tumor biomarkers based on tissue origins, and the application of tumor biomarkers in clinical cancer management. In particular, we highlight the recent advancements in biomarker-based anticancer-targeted therapies which are emerging as breakthroughs and promising cancer therapeutic strategies. We also discuss limitations and challenges that need to be addressed and provide insights and perspectives to turn challenges into opportunities in this field. Collectively, the discovery and application of multiple tumor biomarkers emphasized in this review may provide guidance on improved precision medicine, broaden horizons in future research directions, and expedite the clinical classification of cancer patients according to their molecular biomarkers rather than organs of origin.

β-Catenin Activation Reprograms Ammonia Metabolism to Promote Senescence Resistance in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a typical tumor that undergoes metabolic reprogramming, differing from normal liver tissue in glucose, lipid, nucleic acid, and amino acid metabolism. Although ammonia is a toxic metabolic by-product, it has also been recently recognized as a signaling molecule to activate lipid metabolism, and it can be a nitrogen source for biosynthesis to support tumorigenesis. In this study, we revealed that β-catenin activation increases ammonia production in HCC mainly by stimulating glutaminolysis. β-Catenin/LEF1 activated the transcription of the glutamate dehydrogenase GLUD1, which then promoted ammonia utilization to enhance the production of glutamate, aspartate, and proline as evidenced by 15NH4Cl metabolic flux. β-Catenin/TCF4 induced the transcription of SLC4A11, an ammonia transporter, to excrete excess ammonia. SLC4A11 was upregulated in HCC tumor tissues, and high SLC4A11 expression was associated with poor prognosis and advanced disease stages. Loss of SLC4A11 induced HCC cell senescence in vitro by blocking ammonia excretion and reduced β-catenin-driven tumor growth in vivo. Furthermore, elevated levels of plasma ammonia promoted the progression of β-catenin mutant HCC, which was impeded by SLC4A11 deficiency. Downregulation of SLC4A11 led to ammonia accumulation in tumor interstitial fluid and decreased plasma ammonia levels in HCC with activated β-catenin. Altogether, this study indicates that β-catenin activation reprograms ammonia metabolism and that blocking ammonia excretion by targeting SLC4A11 could be a promising approach to induce senescence in β-catenin mutant HCC.

SIGNIFICANCE

Ammonia metabolism reprogramming mediated by aberrant activation of β-catenin induces resistance to senescence in HCC and can be targeted by inhibiting SLC4A11 as a potential therapy for β-catenin mutant liver cancer.

Single-cell senescence identification reveals senescence heterogeneity, trajectory, and modulators

Cellular senescence underlies many aging-related pathologies, but its heterogeneity poses challenges for studying and targeting senescent cells. We present here a machine learning program senescent cell identification (SenCID), which accurately identifies senescent cells in both bulk and single-cell transcriptome. Trained on 602 samples from 52 senescence transcriptome datasets spanning 30 cell types, SenCID identifies six major senescence identities (SIDs). Different SIDs exhibit different senescence baselines, stemness, gene functions, and responses to senolytics. SenCID enables the reconstruction of senescent trajectories under normal aging, chronic diseases, and COVID-19. Additionally, when applied to single-cell Perturb-seq data, SenCID helps reveal a hierarchy of senescence modulators. Overall, SenCID is an essential tool for precise single-cell analysis of cellular senescence, enabling targeted interventions against senescent cells.

Blocking of FGFR4 signaling by F30 inhibits hepatocellular carcinoma cell proliferation through HMOX1-dependent ferroptosis pathway

Excessive activation of FGF19/fibroblast growth factor receptor 4 (FGFR4) signaling is associated with poor survival of patients with hepatocellular carcinoma (HCC). FGFR4 inhibitors show promise for HCC treatment. F30, an indazole derivative designed through computer-aided drug design targeting FGFR4, demonstrated anti-HCC activity as described in our previous studies. However, the precise molecular mechanisms underlying F30's anticancer effects remain largely unexplored. We report here that F30 could effectively induce ferroptosis in HCC cells. The concentrations of cellular ferrous iron, the peroxidation of cell membranes and the homeostasis of reduced glutathione (GSH)/oxidized glutathione disulfide (GSSG) were dysregulated by F30, thereby affecting cellular redox status. Induction of ferroptosis in HCC by F30 was inhibited by specific ferroptosis inhibitor ferrostatin-1. F30 upregulates various ferroptosis-related genes, including the heme oxygenase enzymes 1 (HMOX1), a key mediator of redox regulation. Surprisingly, F30-induced ferroptosis in HCC is dependent on HMOX1. The dysregulation of cellular ferrous iron concentrations and cell membrane peroxidation was rescued when knocking down HMOX1 with specific small interfering RNA. These findings shed light on the molecular mechanisms underlying FGFR4-targeting F30's anti-HCC effects and suggest that FGFR4 inactivation could be beneficial for HCC treatment involving ferroptosis.

Cellular senescence in cancer: molecular mechanisms and therapeutic targets

Aging exhibits several hallmarks in common with cancer, such as cellular senescence, dysbiosis, inflammation, genomic instability, and epigenetic changes. In recent decades, research into the role of cellular senescence on tumor progression has received widespread attention. While how senescence limits the course of cancer is well established, senescence has also been found to promote certain malignant phenotypes. The tumor-promoting effect of senescence is mainly elicited by a senescence-associated secretory phenotype, which facilitates the interaction of senescent tumor cells with their surroundings. Targeting senescent cells therefore offers a promising technique for cancer therapy. Drugs that pharmacologically restore the normal function of senescent cells or eliminate them would assist in reestablishing homeostasis of cell signaling. Here, we describe cell senescence, its occurrence, phenotype, and impact on tumor biology. A "one-two-punch" therapeutic strategy in which cancer cell senescence is first induced, followed by the use of senotherapeutics for eliminating the senescent cells is introduced. The advances in the application of senotherapeutics for targeting senescent cells to assist cancer treatment are outlined, with an emphasis on drug categories, and the strategies for their screening, design, and efficient targeting. This work will foster a thorough comprehension and encourage additional research within this field.

Nanosystem Delivers Senescence Activators and Immunomodulators to Combat Liver Cancer

CD47 blockade has emerged as a promising immunotherapy against liver cancer. However, the optimization of its antitumor effectiveness using efficient drug delivery systems or combinations of therapeutic agents remains largely incomplete. Here, patients with liver cancer co-expressing CD47 and CDC7 (cell division cycle 7, a negative senescence-related gene) are found to have the worst prognosis. Moreover, CD47 is highly expressed, and senescence is inhibited after the development of chemoresistance, suggesting that combination therapy targeting CD47 and CDC7 to inhibit CD47 and induce senescence may be a promising strategy for liver cancer. The efficacy of intravenously administered CDC7 and CD47 inhibitors is limited by low uptake and short circulation times. Here, inhibitors are coloaded into a dual-targeted nanosystem. The sequential release of the inhibitors from the nanosystem under acidic conditions first induces cellular senescence and then promotes immune responses. In an in situ liver cancer mouse model and a chemotherapy-resistant mouse model, the nanosystem effectively inhibited tumor growth by 90.33% and 85.15%, respectively. Overall, the nanosystem in this work achieved the sequential release of CDC7 and CD47 inhibitors in situ to trigger senescence and induce immunotherapy, effectively combating liver cancer and overcoming chemoresistance.

Prognostic value and potential mechanism of cellular senescence and tumor microenvironment in hepatocellular carcinoma: Insights from bulk transcriptomics and single-cell sequencing analysis

The high mortality rate and postoperative recurrence of hepatocellular carcinoma (HCC) contribute to the burden on society and healthcare. The prognostic value and underlying mechanisms of cellular senescence and tumor microenvironment (TME) in HCC remain unclear. Bulk transcriptomic data were obtained from 368 HCC samples in The Cancer Genome Atlas-liver hepatocellular carcinoma cohort and 64 samples from the GSE116174 dataset. Single-cell RNA sequencing (scRNA-seq) data of HCC were obtained from the GSE149614 dataset, including 18 tumor samples from 10 patients. Prognosis-related cellular senescence genes and immune cells were identified through univariate analysis. Least absolute shrinkage and selection operator regression analysis was performed to construct the CellAge score and TME score, both of which were identified as independent prognostic factors for HCC based on multivariate Cox analysis. The combined CellAge and TME scores showed improved prognostic stratification for HCC patients, as confirmed by multivariate Cox analysis (p < .001). The gene set enrichment analysis (GSEA) revealed enrichment of the extracellular matrix receptor interaction signaling pathway in the group with high CellAge scores and low TME scores, which exhibited a worse prognosis. Single-cell sequencing results revealed higher expression activity of the cAMP response element modulator (CREM) extended transcription factor in HCC cells and most immune cells, indicating its involvement in TME remodeling. Finally, the tumor immune dysfunction and exclusion (TIDE) analysis demonstrated that the combined scores could predict the outcomes of immune therapy in patients with HCC. In conclusion, cellular senescence contributes to TME remodeling in HCC, and the developed CellAge and TME scores serve as independent prognostic factors and predictors of immune therapy in HCC.

A Conversation with ChatGPT on Contentious Issues in Senescence and Cancer Research

Artificial intelligence (AI) platforms, such as Generative Pretrained Transformer (ChatGPT), have achieved a high degree of popularity within the scientific community due to their utility in providing evidence-based reviews of the literature. However, the accuracy and reliability of the information output and the ability to provide critical analysis of the literature, especially with respect to highly controversial issues, has generally not been evaluated. In this work, we arranged a question/answer session with ChatGPT regarding several unresolved questions in the field of cancer research relating to therapy-induced senescence (TIS), including the topics of senescence reversibility, its connection to tumor dormancy, and the pharmacology of the newly emerging drug class of senolytics. ChatGPT generally provided responses consistent with the available literature, although occasionally overlooking essential components of the current understanding of the role of TIS in cancer biology and treatment. Although ChatGPT, and similar AI platforms, have utility in providing an accurate evidence-based review of the literature, their outputs should still be considered carefully, especially with respect to unresolved issues in tumor biology. SIGNIFICANCE STATEMENT: Artificial Intelligence platforms have provided great utility for researchers to investigate biomedical literature in a prompt manner. However, several issues arise when it comes to certain unresolved biological questions, especially in the cancer field. This work provided a discussion with ChatGPT regarding some of the yet-to-be-fully-elucidated conundrums of the role of therapy-induced senescence in cancer treatment and highlights the strengths and weaknesses in utilizing such platforms for analyzing the scientific literature on this topic.

Cotargeting CDK4/6 and BRD4 Promotes Senescence and Ferroptosis Sensitivity in Cancer

Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors are approved for breast cancer treatment and show activity against other malignancies, including KRAS-mutant non-small cell lung cancer (NSCLC). However, the clinical efficacy of CDK4/6 inhibitors is limited due to frequent drug resistance and their largely cytostatic effects. Through a genome-wide cDNA screen, we identified that bromodomain-containing protein 4 (BRD4) overexpression conferred resistance to the CDK4/6 inhibitor palbociclib in KRAS-mutant NSCLC cells. Inhibition of BRD4, either by RNA interference or small-molecule inhibitors, synergized with palbociclib to induce senescence in NSCLC cells and tumors, and the combination prolonged survival in a KRAS-mutant NSCLC mouse model. Mechanistically, BRD4-inhibition enhanced cell-cycle arrest and reactive oxygen species (ROS) accumulation, both of which are necessary for senescence induction; this in turn elevated GPX4, a peroxidase that suppresses ROS-triggered ferroptosis. Consequently, GPX4 inhibitor treatment selectively induced ferroptotic cell death in the senescent cancer cells, resulting in tumor regression. Cotargeting CDK4/6 and BRD4 also promoted senescence and ferroptosis vulnerability in pancreatic and breast cancer cells. Together, these findings reveal therapeutic vulnerabilities and effective combinations to enhance the clinical utility of CDK4/6 inhibitors.

SIGNIFICANCE

The combination of cytostatic CDK4/6 and BRD4 inhibitors induces senescent cancer cells that are primed for activation of ferroptotic cell death by targeting GPX4, providing an effective strategy for treating cancer.

Integrative analysis of senescence-related genes identifies robust prognostic clusters with distinct features in hepatocellular carcinoma

INTRODUCTION

Senescence refers to a state of permanent cell growth arrest and is regarded as a tumor suppressive mechanism, whereas accumulative evidence demonstrate that senescent cells play an adverse role during cancer progression. The scarcity of specific and reliable markers reflecting senescence level in cancer impede our understanding of this biological basis.

OBJECTIVES

Senescence-related genes (SRGs) were collected for integrative analysis to reveal the role of senescence in hepatocellular carcinoma (HCC).

METHODS

Consensus clustering was used to subtype HCC based on SRGs. Several computational methods, including single sample gene set enrichment analysis (ssGSEA), fuzzy c-means algorithm, were performed. Data of drug sensitivities were utilized to screen potential therapeutic agents for different senescence patients. Additionally, we developed a method called signature-related gene analysis (SRGA) for identification of markers relevant to phenotype of interest. Experimental strategies consisting quantitative real-time PCR (qRT-PCR), β-galactosidase assay, western blot, and tumor-T cell co-culture system were used to validate the findings in vitro.

RESULTS

We identified three robust prognostic clusters of HCC patients with distinct survival outcome, mutational landscape, and immune features. We further extracted signature genes of senescence clusters to construct the senescence scoring system and profile senescence level in HCC at bulk and single-cell resolution. Senescence-induced stemness reprogramming was confirmed both in silico and in vitro. HCC patients with high senescence were immune suppressed and sensitive to Tozasertib and other drugs. We suggested that MAFG, PLIN3, and 4 other genes were pertinent to HCC senescence, and MAFG potentially mediated immune suppression, senescence, and stemness.

CONCLUSION

Our findings provide insights into the role of SRGs in patients stratification and precision medicine.

Assessment of disease control rate and safety of sorafenib in targeted therapy for advanced liver cancer

OBJECTIVE

The clinical efficacy and safety of sorafenib in patients with advanced liver cancer (ALC) were evaluated based on transarterial chemoembolization (TACE).

METHODS

92 patients with ALC admitted to our hospital from May 2020 to August 2022 were randomly rolled into a control (Ctrl) group and an observation (Obs) group, with 46 patients in each. Patients in the Ctrl group received TACE treatment, while those in the Obs group received sorafenib molecular targeted therapy (SMTT) on the basis of the treatment strategy in the Ctrl group (400 mg/dose, twice daily, followed by a 4-week follow-up observation). Clinical efficacy, disease control rate (DCR), survival time (ST), immune indicators (CD3+, CD4+, CD4+/CD8+), and adverse reactions (ARs) (including mild fatigue, liver pain, hand-foot syndrome (HFS), diarrhea, and fever) were compared for patients in different groups after different treatments.

RESULTS

the DCR in the Obs group (90%) was greatly higher to that in the Ctrl group (78%), showing an obvious difference (P < 0.05). The median ST in the Obs group was obviously longer and the median disease progression time (DPT) was shorter, exhibiting great differences with those in the Ctrl group (P < 0.05). Moreover, no great difference was observed in laboratory indicators between patients in various groups (P > 0.05). After treatment, the Obs group exhibited better levels in all indicators. Furthermore, the incidence of ARs in the Obs group was lower and exhibited a sharp difference with that in the Ctrl group (P < 0.05).

CONCLUSION

SMTT had demonstrated good efficacy in patients with ALC, improving the DCR, enhancing the immune response of the body, and reducing the incidence of ARs, thereby promoting the disease outcome. Therefore, it was a treatment method worthy of promotion and application.

Loss of the vitamin D receptor triggers senescence in chronic myeloid leukemia via DDIT4-mediated DNA damage

Chronic myeloid leukemia (CML) is a hematopoietic malignancy driven by the fusion gene BCR::ABL1. Drug resistance to tyrosine kinase inhibitors (TKIs), due to BCR::ABL1 mutations and residual leukemia stem cells (LSCs), remains a major challenge in CML treatment. Here, we revealed the requirement of the vitamin D receptor (VDR) in the progression of CML. VDR was upregulated by BCR::ABL1 and highly expressed in CML cells. Interestingly, VDR knockdown inhibited the proliferation of CML cells driven by both BCR::ABL1 and TKI-resistant BCR::ABL1 mutations. Mechanistically, VDR transcriptionally regulated DDIT4 expression; reduced DDIT4 levels upon VDR knockdown triggered DNA damage and senescence via p53 signaling activation in CML cells. Furthermore, VDR deficiency not only suppressed tumor burden and progression in primary CML mice but also reduced the self-renewal capacity of CML-LSCs. Together, our study demonstrated that targeting VDR is a promising strategy to overcome TKI resistance and eradicate LSCs in CML.

Cancer cell genetics shaping of the tumor microenvironment reveals myeloid cell-centric exploitable vulnerabilities in hepatocellular carcinoma

Myeloid cells are abundant and plastic immune cell subsets in the liver, to which pro-tumorigenic, inflammatory and immunosuppressive roles have been assigned in the course of tumorigenesis. Yet several aspects underlying their dynamic alterations in hepatocellular carcinoma (HCC) progression remain elusive, including the impact of distinct genetic mutations in shaping a cancer-permissive tumor microenvironment (TME). Here, in newly generated, clinically-relevant somatic female HCC mouse models, we identify cancer genetics' specific and stage-dependent alterations of the liver TME associated with distinct histopathological and malignant HCC features. Mitogen-activated protein kinase (MAPK)-activated, NrasG12D-driven tumors exhibit a mixed phenotype of prominent inflammation and immunosuppression in a T cell-excluded TME. Mechanistically, we report a NrasG12D cancer cell-driven, MEK-ERK1/2-SP1-dependent GM-CSF secretion enabling the accumulation of immunosuppressive and proinflammatory monocyte-derived Ly6Clow cells. GM-CSF blockade curbs the accumulation of these cells, reduces inflammation, induces cancer cell death and prolongs animal survival. Furthermore, GM-CSF neutralization synergizes with a vascular endothelial growth factor (VEGF) inhibitor to restrain HCC outgrowth. These findings underscore the profound alterations of the myeloid TME consequential to MAPK pathway activation intensity and the potential of GM-CSF inhibition as a myeloid-centric therapy tailored to subsets of HCC patients.

Erianin inhibits tumor growth by promoting ferroptosis and inhibiting invasion in hepatocellular carcinoma through the JAK2/STAT3/SLC7A11 pathway

Iron has been found to be involved in the tumor cell proliferation process, which can lead to the increased sensitivity of cancer cells to ferroptosis. Since erianin is associated with oxidative stress in hepatocellular carcinoma (HCC), we hypothesized that the therapeutic effect and mechanism of erianin on HCC is related to ferroptosis. HCC cells were stimulated with increase of erianin concentrations for 24 h, and the survival rates of Huh-7 and HepG2 cells gradually decreased. After intervention with different doses of erianin, cell proliferation, clone number, and invasion were prominently decreased, apoptosis ratio was increased. Moreover, Nec-1, CQ, and Z-VAD had no effect on the cell viability induced by erianin, while the combination of ferroptosis inhibitors (deferoxamine mesylate, ferrostatin-1, and liproxstatin-1) and erianin prominently increased cell survival rate. Erianin pretreatment induced ferroptosis by enhancing reactive oxygen species, MDA, and Fe2+ levels, and reducing GSH levels. Erianin activated JAK2/STAT3 pathway and inhibited SLC7A11 and GPX4 expression, thereby inducing ferroptosis. Besides, tumor growth was significantly inhibited in the erianin-treated mice, and there was no obvious toxicity in the mice. Erianin reduced proliferation and invasion of HCC cells by inducing ferroptosis by blocking the JAK2/STAT3/SLC7A11 pathway, thereby impeding tumor growth.

Fatty acid synthase (FASN) signalome: A molecular guide for precision oncology

The initial excitement generated more than two decades ago by the discovery of drugs targeting fatty acid synthase (FASN)-catalyzed de novo lipogenesis for cancer therapy was short-lived. However, the advent of the first clinical-grade FASN inhibitor (TVB-2640; denifanstat), which is currently being studied in various phase II trials, and the exciting advances in understanding the FASN signalome are fueling a renewed interest in FASN-targeted strategies for the treatment and prevention of cancer. Here, we provide a detailed overview of how FASN can drive phenotypic plasticity and cell fate decisions, mitochondrial regulation of cell death, immune escape and organ-specific metastatic potential. We then present a variety of FASN-targeted therapeutic approaches that address the major challenges facing FASN therapy. These include limitations of current FASN inhibitors and the lack of precision tools to maximize the therapeutic potential of FASN inhibitors in the clinic. Rethinking the role of FASN as a signal transducer in cancer pathogenesis may provide molecularly driven strategies to optimize FASN as a long-awaited target for cancer therapeutics.