Regulation of Hippo signaling by metabolic pathways in cancer

Identification of distinct profiles of glioblastoma through the immunocapture of extracellular vesicles from patient plasma

Glioblastoma (GBM), a primary brain tumor, exhibits intratumoral heterogeneity and dynamic spatial-temporal changes. GBM-derived extracellular vesicles (EVs), reflecting tumor characteristics, present potential as liquid-biopsy markers for early diagnosis and monitoring. This study aims to evaluate molecular signatures of plasma-derived EVs from GBM patients using a conventional flow cytometer. EVs have been isolated from glioma patients and healthy controls (HCs) plasma using density gradient ultracentrifugation (DGU). EVs were evaluated by bead-based multiplex analysis in a conventional flow cytometer. Principal component analysis (PCA), hierarchical clustering, and correlation analysis provided comprehensive insights into EV characteristics. EVs successfully isolated were visualized in transmission and scanning electron microscopy (STEM). Bead-based multiplex analysis in flow cytometer detected the level of 37 EV surface markers, including tumor-related, cancer stem cell, endothelial cell, and immune cell- specific antigens. PCA identified the EV surface markers that are most significant for differentiating the subjects, and hierarchical clustering revealed four distinct clusters based on EV surface marker levels. EV molecular signature demonstrated considerable heterogeneity across patient clusters. The presence of CD29 emerged not only as a defining factor for a cluster of patients, but also served as a marker to differentiate patients from HCs.

Roles of deubiquitinases in urologic cancers (Review)

Human health is endangered by the occurrence and progression of urological cancers, including renal cell carcinoma, prostate cancer and bladder cancer, which are usually associated with the activation of oncogenic factors and inhibition of cancer suppressors. The primary mechanism for protein breakdown in cells is the ubiquitin-proteasome system, whilst deubiquitinases contribute to the reversal of this process. However, both are important for protein homeostasis. Deubiquitination may also be involved in the control of the cell cycle, proliferation and apoptosis, and dysregulated deubiquitination is associated with the malignant transformation, invasion and metastasis of urologic malignancies. Therefore, a comprehensive summary of the mechanisms underlying deubiquitination in urological cancers may provide novel strategies and insights for diagnosis and treatment. The present review aimed to methodically clarify the role of deubiquitinating enzymes in urinary system cancers as well as their prospective application prospects for clinical treatment.

Urolithin A exerts anti-tumor effects on gastric cancer via activating autophagy-Hippo axis and modulating the gut microbiota

Gastric cancer (GC) treatment regimens are still unsatisfactory. Recently, Urolithin A (UroA) has gained tremendous momentum due to its anti-tumor properties. However, the therapeutic effect and underlying mechanisms of UroA in GC are unclear. We explored the effects and related mechanisms of UroA on GC both in vivo and in vitro. A Cell Counting Kit-8 was used to determine the influence of UroA on the proliferation of GC cell lines. The Autophagy inhibitor 3-methyladenine (3MA) was employed to clarify the role of autophagy in the anti-tumor effect of UroA. Simultaneously, we detected the core-component proteins involved in autophagy and its downstream pathways. Subsequently, the in vivo anti-tumor effect of UroA was determined using a xenograft mouse model. Western blotting was used to detect the core protein components of the anti-tumor pathways, and 16S rDNA sequencing was used to detect the effect of UroA on the gut microbiota. We found that UroA suppressed tumor progression. The use of 3MA undermined the majority of the inhibitory effect of UroA on tumor cell proliferation, further confirming the importance of autophagy in the anti-tumor effect of UroA. Invigorating of autophagy activated the downstream Hippo pathway, thereby inhibiting the Warburg effect and promoting cell apoptosis. In addition, UroA modulated the composition of the gut microbiota, as indicated by the increase of probiotics and the decrease of pathogenic bacteria. Our research revealed new anti-tumor mechanisms of UroA, which may be a promising candidate for GC treatment.

Polyunsaturated fatty acids promote M2-like TAM deposition via dampening RhoA-YAP1 signaling in the ovarian cancer microenvironment

BACKGROUND

Peritoneal metastases frequently occur in epithelial ovarian cancer (EOC), resulting in poor prognosis and survival rates. Tumor-associated-macrophages (TAMs) massively infiltrate into ascites spheroids and are multi-polarized as protumoral M2-like phenotype, orchestrating the immunosuppression and promoting tumor progression. However, the impact of omental conditioned medium/ascites (OCM/AS) on TAM polarization and its function in tumor progression remains elusive.

METHODS

The distribution and polarization of TAMs in primary and omental metastatic EOC patients' tumors and ascites were examined by m-IHC, FACS analysis, and immunofluorescence. QPCR, immunofluorescence, FACS analysis, lipid staining assay, ROS assay, and Seahorse real-time cell metabolic assay characterized TAMs as being polarized in the ascites microenvironment. The oncogenic role of TAMs in tumor cells was demonstrated by co-cultured migration/invasion, proliferation, and spheroid formation assays. Mechanistic studies of the regulations of TAM polarization were performed by using RNA-Seq, GTPase pull-down, G-LISA activation assays, and other biochemical assays. A Yap1 macrophages (MФs) conditional knockout (cKO) mouse model demonstrated the roles of YAP1 in TAM polarization status and its pro-metastatic function. Finally, the anti-metastatic potential of targeting TAMs through restoring YAP1 by pharmacological agonist XMU MP1 was demonstrated in vitro and in vivo.

RESULTS

Abundant polyunsaturated fatty acids (PUFAs) in OCM/AS suppressed RhoA-GTPase activities, which, in turn, downregulated nuclear YAP1 in MФs, leading to increased protumoral TAM polarization accompanied by elevated OXPHOS metabolism. Abolishment of YAP1 in MФs further confirmed that a higher M2/M1 ratio of TAM polarization could alleviate CD8+ T cell infiltration and cytotoxicity in vivo. Consistently, the loss of YAP1 has been observed in EOC metastatic tissues, suggesting its clinical relevance. On the contrary, restoration of YAP1 expression by pharmaceutical inhibition of MST1/2 induced conversion of M2-to-M1-like polarized MФs, elevating the infiltration of CD8+ T cells and attenuating tumor growth.

CONCLUSION

This study revealed that PUFAs-enriched OCM/AS of EOC promotes M2-like TAM polarization through RhoA-YAP1 inhibition, where YAP1 downregulation is required for accelerating protumoral M2-like TAM polarization, thereby causing immunosuppression and enhancing tumor progression. Conversion of M2-to-M1-like polarized MФs through Yap1 activation inhibits tumor progression and contributes to developing potential TAMs-targeted immunotherapies in combating EOC peritoneal metastases.

Gypenoside inhibits gastric cancer proliferation by suppressing glycolysis via the Hippo pathway

Gastric cancer (GC) remains a global disease with a high mortality rate, the lack of effective treatments and the high toxicity of side effects are primary causes for its poor prognosis. Hence, urgent efforts are needed to find safe and effective therapeutic strategies. Gypenoside (Gyp) is a widely used natural product that regulates blood glucose to improve disease progression with few toxic side effects. Given the crucial role of abnormal glycometabolism in driving tumor malignancy, it is important to explore the association between Gyp and glycometabolism in GC and understand the mechanism of action by which Gyp influences glycometabolism. In this study, we demonstrated that Gyp suppresses GC proliferation and migration both in vitro and in vivo. We identified that Gyp suppresses the malignant progression of GC by inhibiting glycolysis using network pharmacology and metabolomics. Transcriptome analysis revealed that the Hippo pathway is a key regulator of glycolysis by Gyp in GC. Furthermore, Gyp induced upregulation of LATS1/2 proteins, leading to increased YAP phosphorylation and decreased TAZ protein expression. The YAP agonist XMU-MP-1 rescued the inhibitory effect of Gyp on GC proliferation by reversing glycolysis. These findings confirmed that Gyp inhibits GC proliferation by targeting glycolysis through the Hippo pathway. Our study examined the role of Gyp in the malignant progression of GC, explored its therapeutic prospects, elucidated a mechanism by which Gyp suppresses GC proliferation through interference with the glycolytic process, thus providing a potential novel therapeutic strategy for GC patients.

Unraveling the intricate relationship between lipid metabolism and oncogenic signaling pathways

Lipids, the primary constituents of the cell membrane, play essential roles in nearly all cellular functions, such as cell-cell recognition, signaling transduction, and energy provision. Lipid metabolism is necessary for the maintenance of life since it regulates the balance between the processes of synthesis and breakdown. Increasing evidence suggests that cancer cells exhibit abnormal lipid metabolism, significantly affecting their malignant characteristics, including self-renewal, differentiation, invasion, metastasis, and drug sensitivity and resistance. Prominent oncogenic signaling pathways that modulate metabolic gene expression and elevate metabolic enzyme activity include phosphoinositide 3-kinase (PI3K)/AKT, MAPK, NF-kB, Wnt, Notch, and Hippo pathway. Conversely, when metabolic processes are not regulated, they can lead to malfunctions in cellular signal transduction pathways. This, in turn, enables uncontrolled cancer cell growth by providing the necessary energy, building blocks, and redox potentials. Therefore, targeting lipid metabolism-associated oncogenic signaling pathways could be an effective therapeutic approach to decrease cancer incidence and promote survival. This review sheds light on the interactions between lipid reprogramming and signaling pathways in cancer. Exploring lipid metabolism as a target could provide a promising approach for creating anticancer treatments by identifying metabolic inhibitors. Additionally, we have also provided an overview of the drugs targeting lipid metabolism in cancer in this review.

Natural medicinal compounds target signal transduction pathways to overcome ABC drug efflux transporter-mediated multidrug resistance in cancer

ATP-binding cassette (ABC) transporters such as ABCB1, ABCG2, and ABCC1 are the major players in drug efflux-mediated multidrug resistance (MDR), which severely affects the efficacy of chemotherapy. Several synthetic compounds block the drug transport by ABC transporters; however, they exhibit a narrow therapeutic window, and produce side effects in non-target normal tissues. Conversely, the downregulation of the expression of ABC drug transporters seems to be a promising strategy to reverse MDR in cancer cells. Several signaling pathways, such as NF-κB, STAT3, Gli, NICD, YAP/TAZ, and Nrf2 upregulate the expression of ABC drug transporters in drug-resistant cancers. Recently, natural medicinal compounds have gained importance to overcome the ABC drug-efflux pump-mediated MDR in cancer. These compounds target transcription factors and the associated signal transduction pathways, thereby downregulating the expression of ABC transporters in drug-resistant cancer cells. Several potent natural compounds have been identified as lead candidates to synergistically enhance chemotherapeutic efficacy, and a few of them are already in clinical trials. Therefore, modulation of signal transduction pathways using natural medicinal compounds for the reversal of ABC drug transporter-mediated MDR in cancer is a novel approach for improving the efficiency of the existing chemotherapeutics. In this review, we discuss the modulatory role of natural medicinal compounds on cellular signaling pathways that regulate the expression of ABC transporters in drug-resistant cancer cells.

Malignant mesothelioma tumours: molecular pathogenesis, diagnosis, and therapies accompanying clinical studies

The pathetic malignant mesothelioma (MM) is a extremely uncommon and confrontational tumor that evolves in the mesothelium layer of the pleural cavities (inner lining- visceral pleura and outer lining- parietal pleura), peritoneum, pericardium, and tunica vaginalis and is highly resistant to standard treatments. In mesothelioma, the predominant pattern of lesions is a loss of genes that limit tumour growth. Despite the worldwide ban on the manufacture and supply of asbestos, the prevalence of mesothelioma continues to increase. Mesothelioma presents and behaves in a variety of ways, making diagnosis challenging. Most treatments available today for MM are ineffective, and the median life expectancy is between 10 and 12 months. However, in recent years, considerable progress has already been made in understanding the genetics and molecular pathophysiology of mesothelioma by addressing hippo signaling pathway. The development and progression of MM are related to many important genetic alterations. This is related to NF2 and/or LATS2 mutations that activate the transcriptional coactivator YAP. The X-rays, CT scans, MRIs, and PET scans are used to diagnose the MM. The MM are treated with surgery, chemotherapy, first-line combination chemotherapy, second-line treatment, radiation therapy, adoptive T-cell treatment, targeted therapy, and cancer vaccines. Recent clinical trials investigating the function of surgery have led to the development of innovative approaches to the treatment of associated pleural effusions as well as the introduction of targeted medications. An interdisciplinary collaborative approach is needed for the effective care of persons who have mesothelioma because of the rising intricacy of mesothelioma treatment. This article highlights the key findings in the molecular pathogenesis of mesothelioma, diagnosis with special emphasis on the management of mesothelioma.

The NDR/LATS protein kinases in neurobiology: Key regulators of cell proliferation, differentiation and migration in the ocular and central nervous system

Nuclear Dbf2-related (NDR) kinases are a subgroup of evolutionarily conserved AGC protein kinases that regulate various aspects of cell growth and morphogenesis. There are 4 NDR protein kinases in mammals, LATS1, LATS2 and STTK8/NDR1, STK38L/NDR2 protein kinases. LATS1 and 2 are core components of the well-studied Hippo pathway, which play a critical role in the regulation of cell proliferation, differentiation, and cell migration via YAP/TAZ transcription factor. The Hippo pathways play an important role in nervous tissue development and homeostasis, especially with regard to the central nervous system (CNS) and the ocular system. The ocular system is a very complex system generated by the interaction in a very tightly coordinated manner of numerous and diverse developing tissues, such as, but not limited to choroidal and retinal blood vessels, the retinal pigmented epithelium and the retina, a highly polarized neuronal tissue. The retina development and maintenance require precise and coordinated regulation of cell proliferation, cell death, migration, morphogenesis, synaptic connectivity, and balanced homeostasis. This review highlights the emerging roles of NDR1 and NDR2 kinases in the regulation of retinal/neuronal function and homeostasis via a noncanonical branch of the Hippo pathway. We highlight a potential role of NDR1 and NDR2 kinases in regulating neuronal inflammation and as potential therapeutic targets for the treatment of neuronal diseases.

A novel mitochondria-related gene signature in esophageal carcinoma: prognostic, immune, and therapeutic features

Esophageal carcinoma (ESCA) is a common and lethal malignant tumor worldwide. The mitochondrial biomarkers were useful in finding significant prognostic gene modules associated with ESCA owing to the role of mitochondria in tumorigenesis and progression. In the present work, we obtained the transcriptome expression profiles and corresponding clinical information of ESCA from The Cancer Genome Atlas (TCGA) database. Differential expressed genes (DEGs) were overlapped with 2030 mitochondria-related genes to get mitochondria-related DEGs. The univariate cox regression, Least Absolute Shrinkage and Selection Operator (LASSO) regression, and multivariate cox regression were sequentially used to define the risk scoring model for mitochondria-related DEGs, and its prognostic value was verified in the external datasets GSE53624. Based on the risk score, ESCA patients were divided into high- and low-risk groups. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA) were performed to further investigate the difference between low- and high-risk groups at the gene pathway level. CIBERSORT was used to evaluate immune cell infiltration. The mutation difference between high- and low-risk groups was compared by using the R package "Maftools". Cellminer was used to assess the association between the risk scoring model and drug sensitivity. As the most important outcome of the study, a 6-gene risk scoring model (APOOL, HIGD1A, MAOB, BCAP31, SLC44A2, and CHPT1) was constructed from 306 mitochondria-related DEGs. Pathways including the "hippo signaling pathway" and "cell-cell junction" were enriched in the DEGs between high and low groups. According to CIBERSORT, samples with high-risk scores demonstrated a higher abundance of CD4⁺ T cells, NK cells, M0 and M2 macrophages, and a lower abundance of M1 macrophages. The immune cell marker genes were correlated with the risk score. In mutation analysis, the mutation rate of TP53 was significantly different between the high- and low-risk groups. Drugs with a strong correlation with the risk model were selected. In conclusion, we focused on the role of mitochondria-related genes in cancer development and proposed a prognostic signature for individualized integrative assessment.

Heterotypic signaling of cancer-associated fibroblasts in shaping the cancer cell drug resistance

The context-dependent reciprocal interaction between the cancer cells and surrounding fibroblasts is imperative for regulating malignant potential, metabolic reprogramming, immunosuppression, and ECM deposition. However, recent evidence also suggests that cancer-associated fibroblasts induce chemoresistance in cancer cells to various anticancer regimens. Because of the protumorigenic function of cancer-associated fibroblasts, these stromal cell types have emerged as fascinating therapeutic targets for cancer. However, this notion was recently challenged by studies that targeted cancer-associated fibroblasts and highlighted the underlying heterogeneity by identifying a subset of these cells with tumor-restricting functions. Hence, it is imperative to understand the heterogeneity and heterotypic signaling of cancer-associated fibroblasts to target tumor-promoting signaling processes by sparing tumor-restricting ones. In this review, we discuss the heterogeneity and heterotypic signaling of cancer-associated fibroblasts in shaping drug resistance and also list the cancer-associated fibroblast-targeting therapeutics.

N1-methyladenosine methylation-related metabolic genes signature and subtypes for predicting prognosis and immune microenvironment in osteosarcoma

N1-methyladenosine methylation (m1A), as an important RNA methylation modification, regulates the development of many tumours. Metabolic reprogramming is one of the important features of tumour cells, and it plays a crucial role in tumour development and metastasis. The role of RNA methylation and metabolic reprogramming in osteosarcoma has been widely reported. However, the potential roles and mechanisms of m1A-related metabolic genes (MRmetabolism) in osteosarcoma have not been currently described. All of MRmetabolism were screened, then selected two MRmetabolism by least absolute shrinkage and selection operator and multifactorial regression analysis to construct a prognostic signature. Patients were divided into high-risk and low-risk groups based on the median riskscore of all patients. After randomizing patients into train and test cohorts, the reliability of the prognostic signature was validated in the whole, train and test cohort, respectively. Subsequently, based on the expression profiles of the two MRmetabolism, we performed consensus clustering to classify patients into two clusters. In addition, we explored the immune infiltration status of different risk groups and different clusters by CIBERSORT and single sample gene set enrichment analysis. Also, to better guide individualized treatment, we analyzed the immune checkpoint expression differences and drug sensitivity in the different risk groups and clusters. In conclusion, we constructed a MRmetabolism prognostic signature, which may help to assess patient prognosis, immunotherapy response.

Crosstalk between Hypoxia and Extracellular Matrix in the Tumor Microenvironment in Breast Cancer

Even though breast cancer is the most diagnosed cancer among women, treatments are not always successful in preventing its progression. Recent studies suggest that hypoxia and the extracellular matrix (ECM) are important in altering cell metabolism and tumor metastasis. Therefore, the aim of this review is to study the crosstalk between hypoxia and the ECM and to assess their impact on breast cancer progression. The findings indicate that hypoxic signaling engages multiple mechanisms that directly contribute to ECM remodeling, ultimately increasing breast cancer aggressiveness. Second, hypoxia and the ECM cooperate to alter different aspects of cell metabolism. They mutually enhance aerobic glycolysis through upregulation of glucose transport, glycolytic enzymes, and by regulating intracellular pH. Both alter lipid and amino acid metabolism by stimulating lipid and amino acid uptake and synthesis, thereby providing the tumor with additional energy for growth and metastasis. Third, YAP/TAZ signaling is not merely regulated by the tumor microenvironment and cell metabolism, but it also regulates it primarily through its target c-Myc. Taken together, this review provides a better understanding of the crosstalk between hypoxia and the ECM in breast cancer. Additionally, it points to a role for the YAP/TAZ mechanotransduction pathway as an important link between hypoxia and the ECM in the tumor microenvironment, driving breast cancer progression.

Microtubule-affinity regulating kinase 4: A potential drug target for cancer therapy

The human genome encodes more than 500 protein kinases that work by transferring the γ-phosphate group from ATP to serine, threonine, or tyrosine (Ser/Thr/Tyr) residues. Various kinases are associated with the onset of cancer and its further progression. The recent advancements in developing small-molecule kinase inhibitors to treat different cancer types have shown noticeable results in clinical therapies. Microtubule-affinity regulating kinase 4 (MARK-4) is a Ser/Thr protein kinase that relates structurally to AMPK/Snf1 subfamily of the CaMK kinases. The protein kinase modulates major signalling pathways such as NF-κB, mTOR and the Hippo-signalling pathway. MARK4 is associated with various cancer types due to its important role in regulating microtubule dynamics and subsequent cell division. Aberrant expression of MARK4 is linked with several pathologies such as cancer, Alzheimer's disease, obesity, etc. This review provides detailed information on structural aspects of MARK4 and its role in various signalling pathways related to cancer. Several therapeutic molecules were designed to inhibit the MARK4 activity from controlling associated diseases. The review further highlights kinase-targeted drug discovery and development in oncology and cancer therapies. Finally, we summarize the latest findings regarding the role of MARK4 in cancer, diabetes, and neurodegenerative disease path to provide a solid rationale for future investigation and therapeutic intervention.

The FOXO family of transcription factors: key molecular players in gastric cancer

Gastric cancer (GC) is the fifth most frequently diagnosed cancer worldwide and the third leading cause of cancer-related death with an oncological origin. Despite its decline in incidence and mortality in recent years, GC remains a global public problem that seriously threatens patients' health and lives. The forkhead box O proteins (FOXOs) are a family of evolutionarily conserved transcription factors (TFs) with crucial roles in cell fate decisions. In mammals, the FOXO family consists of four members FOXO1, 3a, 4, and 6. FOXOs play crucial roles in a variety of biological processes, such as development, metabolism, and stem cell maintenance, by regulating the expression of their target genes in space and time. An accumulating amount of evidence has shown that the dysregulation of FOXOs is involved in GC progression by affecting multiple cellular processes, including proliferation, apoptosis, invasion, metastasis, cell cycle progression, carcinogenesis, and resistance to chemotherapeutic drugs. In this review, we systematically summarize the recent findings on the regulatory mechanisms of FOXO family expression and activity and elucidate its roles in GC progression. Moreover, we also highlight the clinical implications of FOXOs in GC treatment.

YAP and TAZ: Monocorial and bicorial transcriptional co-activators in human cancers

The transcriptional regulators YAP and TAZ are involved in numerous physiological processes including organ development, growth, immunity and tissue regeneration. YAP and TAZ dysregulation also contribute to tumorigenesis, thereby making them attractive cancer therapeutic targets. Arbitrarily, YAP and TAZ are often considered as a single protein, and are referred to as YAP/TAZ in most studies. However, increasing experimental evidences documented that YAP and TAZ perform both overlapping and distinct functions in several physiological and pathological processes. In addition to regulating distinct processes, YAP and TAZ are also regulated by distinct upstream cues. The aim of the review is to describe the distinct roles of YAP and TAZ focusing particularly on cancer. Therapeutic strategies targeting either YAP and TAZ proteins or only one of them should be carefully evaluated. Selective targeting of YAP or TAZ may in fact impair different pathways and determine diverse clinical outputs.

Role of IQ Motif-Containing GTPase-Activating Proteins in Hepatocellular Carcinoma

IQ motif-containing GTPase-activating proteins (IQGAPs) are a class of scaffolding proteins, including IQGAP1, IQGAP2, and IQGAP3, which govern multiple cellular activities by facilitating cytoskeletal remodeling and cellular signal transduction. The role of IQGAPs in cancer initiation and progression has received increasing attention in recent years, especially in hepatocellular carcinoma (HCC), where the aberrant expression of IQGAPs is closely related to patient prognosis. IQGAP1 and 3 are upregulated and are considered oncogenes in HCC, while IQGAP2 is downregulated and functions as a tumor suppressor. This review details the three IQGAP isoforms and their respective structures. The expression and role of each protein in different liver diseases and mainly in HCC, as well as the underlying mechanisms, are also presented. This review also provides a reference for further studies on IQGAPs in HCC.