Co-expression of Rho guanine nucleotide exchange factor 5 and Src associates with poor prognosis of patients with resected non-small cell lung cancer

Exploring manzamine a: a promising anti-lung cancer agent from marine sponge Haliclona sp

Manzamine A (MA), a bioactive compound derived from the marine sponge Haliclona sp., shows considerable therapeutic potential, particularly in the treatment of various cancer types. Extracted with acetone and purified through chromatography, MA exhibits a bioavailability of 20.6% when administered orally in rats, underscoring its feasibility for therapeutic use. This compound disrupts key cellular mechanisms essential for cancer progression, including microtubule dynamics and DNA replication enzymes, demonstrating strong anti-proliferative effects against multiple cancer cell lines while sparing normal cells. Additionally, network pharmacology and molecular docking studies reveal MA's interactions with important targets related to lung cancer progression, such as EGFR and SRC, bolstering its potential as a novel anti-lung cancer agent. Pathway analyses further indicate that MA influences critical signaling pathways involved in tumor growth and metastasis. Given the urgent need for effective treatments against drug-resistant cancers and the limited toxicity profile of MA, further exploration of its pharmacological benefits and mechanism could pave the way for new therapeutic strategies in lung cancer.

High expression of ARHGEF5 predicts unfavorable prognosis in acute myeloid leukemia

Acute myeloid leukemia (AML) is a highly heterogeneous hematological neoplasm, highlighting the need for new molecular markers to improve prognosis prediction and therapeutic strategies. While Rho guanine nucleotide exchange factor 5 (ARHGEF5) is known to be overexpressed in various cancers, its role in AML is not well understood. This study investigates the correlation between ARHGEF5 expression and AML using data from the Cancer Genome Atlas (TCGA). ARHGEF5 expression levels in AML patients and normal samples were compared using the Wilcoxon rank-sum test. The Kaplan-Meier method and Cox regression analysis (CRA) assessed the association between ARHGEF5 expression and patient survival. A prognostic nomogram was constructed using CRA, incorporating patient age and cytogenetic risk.Our findings indicate significant overexpression of ARHGEF5 in AML compared to normal samples. Elevated ARHGEF5 levels were associated with poor prognosis, particularly in patients ≤ 60 years, those with NPM1 mutations, FLT3 mutation-positive, and wild-type RAS (P < 0.05). CRA confirmed that high ARHGEF5 expression independently predicts poor prognosis. Additionally, 412 differentially expressed genes (DEGs) were identified between high and low ARHGEF5 expression groups, with 216 genes upregulated and 196 downregulated. Pathway enrichment analyses using GO and KEGG, along with protein-protein interaction network and single sample gene set enrichment analyses, revealed key pathways and immune cell associations linked to ARHGEF5. These findings suggest that ARHGEF5 overexpression could serve as a biomarker for unfavorable outcomes in AML, providing insights into the underlying mechanisms of AML onset and progression.

Ephexin3/ARHGEF5 Together with Cell Migration Signaling Partners within the Tumor Microenvironment Define Prognostic Transcriptional Signatures in Multiple Cancer Types

Cancer cell migration involves a repertoire of signaling proteins that lead cytoskeleton reorganization as a critical step in metastatic dissemination. RhoGEFs are multidomain effectors that integrate signaling inputs to activate the molecular switches that orchestrate actin cytoskeleton reorganization. Ephexins, a group of five RhoGEFs, play oncogenic roles in invasive and metastatic cancer, leading to a mechanistic hypothesis about their function as signaling nodes assembling functional complexes that guide cancer cell migration. To identify clinically significant Ephexin signaling partners, we applied three systematic data mining strategies, based on the screening of essential Ephexins in multiple cancer cell lines and the identification of coexpressed signaling partners in the TCGA cancer patient datasets. Based on the domain architecture of encoded proteins and gene ontology criteria, we selected Ephexin signaling partners with a role in cytoskeletal reorganization and cell migration. We focused on Ephexin3/ARHGEF5, identified as an essential gene in multiple cancer cell types. Based on significant coexpression data and coessentiality, the signaling repertoire that accompanies Ephexin3 corresponded to three groups: pan-cancer, cancer-specific and coessential. To further select the Ephexin3 signaling partners likely to be relevant in clinical settings, we first identified those whose high expression was statistical linked to shorter patient survival. The resulting Ephexin3 transcriptional signatures represent significant accumulated risk, predictive of shorter survival, in 17 cancer types, including PAAD, LUAD, LGG, OSC, AML, KIRC, THYM, BLCA, LIHC and UCEC. The signaling landscape that accompanies Ephexin3 in various cancer types included the tyrosine kinase receptor MET and the tyrosine phosphatase receptor PTPRF, the serine/threonine kinases MARK2 and PAK6, the Rho GTPases RHOD, RHOF and RAC1, and the cytoskeletal regulator DIAHP1. Our findings set the basis to further explore the role of Ephexin3/ARHGEF5 as an essential effector and signaling hub in cancer cell migration.

Determining the mechanism of action of the Qishan formula against lung adenocarcinoma by integration of network pharmacology, molecular docking, and proteomics

BACKGROUND

Lung adenocarcinoma (LUAD) is the main pathological type of lung cancer. Qishan formula (QSF) is reportedly efficacious against LUAD. However, its mechanisms of action currently remain elusive. Therefore, network pharmacology, molecular docking techniques and proteomics were used to verify the potential pharmacological effects of QSF in the treatment of LUAD.

METHODS

The active ingredients and potential targets of QSF were obtained from the TCMSP, chemical source network and construct a drug-component-target networks using Cytoscape v3.7.2. Data for disease targets were obtained from 5 databases: TCGA, OMIM, DrugBank, DisGeNET, and GeneCards. Drug disease cross targets were used to construct protein-protein interaction networks for selecting the core targets using the STRING database and enrichment pathway networks using the DAVID database. Finally, TMT quantitative proteomics was used to identify the possible core targets and action pathways. Molecular docking to verify the affinity between components and targets.

RESULTS

Network pharmacology identified core components of QSF against LUAD included baicalein, methylophiopogonone B, quercetin, kaempferol, isorhamnetin, and luteolin, which can act on 10 key targets (SRC, TP53, PIK3R1, MAPK3, STAT3, MAKP1, HSP90AA1, PIK3CA, HRAS, and AKT1). QSF might play a therapeutic role in LUAD by regulating biological processes such as signal transduction, protein phosphorylation, cell proliferation, and apoptosis, as well as the PI3K/AKT, MAPK, FoxO, and other signaling pathways. Proteomics identified 207 differentially expressed proteins, and by integrating with network pharmacology and molecular docking results we found that 6 core components of QSF may target TP53 against LUAD through the PI3K/AKT signaling pathway.

CONCLUSION

QSF is a multitarget recipe potentially exerting pleiotropic effects in LUAD.

The Crosstalk between Src and Hippo/YAP Signaling Pathways in Non-Small Cell Lung Cancer (NSCLC)

The advancement of new therapies, including targeted therapies and immunotherapies, has improved the survival of non-small-cell lung cancer (NSCLC) patients in the last decade. Some NSCLC patients still do not benefit from therapies or encounter progressive disease during the course of treatment because they have intrinsic resistance, acquired resistance, or lack a targetable driver mutation. More investigations on the molecular biology of NSCLC are needed to find useful biomarkers for current therapies and to develop novel therapeutic strategies. Src is a non-receptor tyrosine kinase protein that interacts with cell surface growth factor receptors and the intracellular signaling pathway to maintain cell survival tumorigenesis in NSCLC. The Yes-associated protein (YAP) is one of the main effectors of the Hippo pathway and has been identified as a promoter of drug resistance, cancer progression, and metastasis in NSCLC. Here, we review studies that have investigated the activation of YAP as mediated by Src kinases and demonstrate that Src regulates YAP through three main mechanisms: (1) direct phosphorylation; (2) the activation of pathways repressing Hippo kinases; and (3) Hippo-independent mechanisms. Further work should focus on the efficacy of Src inhibitors in inhibiting YAP activity in NSCLC. In addition, future efforts toward developing potentially reasonable combinations of therapy targeting the Src-YAP axis using other therapies, including targeted therapies and/or immunotherapies, are warranted.

Bioinformatics Analysis of Microarray Datasets to Identify Prognostic Factors in Lung Adenocarcinoma

Most patients with lung adenocarcinoma (LUAD) present high recurrence rate and poor prognosis after therapy. Therefore, the purpose of this study was to identify prognostic factors involved in LUAD. Five microarray datasets (including GSE75037, GSE63459, GSE43458, GSE32863, and GSE10072) were downloaded. After data preprocessing and quality control, meta-analysis was performed to screen differentially expressed genes (DEGs) using the MetaDE.ES method in MetaDE package. Subsequently, network construction and module identification were conducted by the Weighted Gene Co-expression Network Analysis method. Moreover, survival-associated genes were identified using the univariate and multivariate Cox regression method in survival package. The risk score model was constructed by prognosis associated genes, followed by the Kaplan-Meier survival analysis. Oncomine expressions analysis of several prognosis associated genes was conducted. The expression levels of key genes were detected using quantitative real-time PCR experiments. A total of 1434 DEGs between LUAD and normal samples were identified. Nine disease-associated modules were identified, in which M8 module was most correlated with LAUD phenotype. A total of 89 indicators (including T stage, M stage, and ADIPOR2) were significantly associated with LAUD prognosis, while only T stage and 9 DEGs (e.g., ARHGEF3, GTSE1, RBM15 and CD52) were retained as the potential prognostic factors following multivariate COX regression analysis. The upregulated adiponectin receptor 2 (ADIPOR2), rho guanine nucleotide exchange factor 3 (ARHGEF3), and CD52 molecule (CD52), and downregulated GTSE1 were validated in LAUD samples of Oncomine database. Importantly, ADIPOR2 and ARHGEF3 were confirmed to be down-regulated in LUAD tissues. ADIPOR2, ARHGEF3, G2 and S-phase expressed 1 (GTSE1) and CD52 might be promising prognostic factors in LUAD.

The E3 ubiquitin ligase TRIM7 suppressed hepatocellular carcinoma progression by directly targeting Src protein

Aberrant Src kinase activity is known to be involved in a variety of human malignancies, whereas the regulatory mechanism of Src has not been completely clarified. Here, we demonstrated that tripartite motif containing 7 (TRIM7) directly interacted with Src, induced Lys48-linked polyubiquitination of Src and reduced the abundance of Src protein in hepatocellular carcinoma (HCC) cells. We further identified TRIM7 as a tumor suppressor in HCC cells through its negative modulation of the Src-mTORC1-S6K1 axis in vivo and in vitro in several HCC models. Moreover, we verified the dysregulated expression of TRIM7 in clinical liver cancer tissues and its negative correlation with Src protein in clinical HCC specimens. Overall, we demonstrated that TRIM7 suppressed HCC progression through its direct negative regulation of Src and modulation of the Src-mTORC1-S6K1 axis; thus, we provided a novel insight into the development of HCC and defined a promising therapeutic strategy for cancers with overactive Src by modulating TRIM7.

Induction of Acquired Resistance towards EGFR Inhibitor Gefitinib in a Patient-Derived Xenograft Model of Non-Small Cell Lung Cancer and Subsequent Molecular Characterization

In up to 30% of non-small cell lung cancer (NSCLC) patients, the oncogenic driver of tumor growth is a constitutively activated epidermal growth factor receptor (EGFR). Although these patients gain great benefit from treatment with EGFR tyrosine kinase inhibitors, the development of resistance is inevitable. To model the emergence of drug resistance, an EGFR-driven, patient-derived xenograft (PDX) NSCLC model was treated continuously with Gefitinib in vivo. Over a period of more than three months, three separate clones developed and were subsequently analyzed: Whole exome sequencing and reverse phase protein arrays (RPPAs) were performed to identify the mechanism of resistance. In total, 13 genes were identified, which were mutated in all three resistant lines. Amongst them the mutations in NOMO2, ARHGEF5 and SMTNL2 were predicted as deleterious. The 53 mutated genes specific for at least two of the resistant lines were mainly involved in cell cycle activities or the Fanconi anemia pathway. On a protein level, total EGFR, total Axl, phospho-NFκB, and phospho-Stat1 were upregulated. Stat1, Stat3, MEK1/2, and NFκB displayed enhanced activation in the resistant clones determined by the phosphorylated vs. total protein ratio. In summary, we developed an NSCLC PDX line modelling possible escape mechanism under EGFR treatment. We identified three genes that have not been described before to be involved in an acquired EGFR resistance. Further functional studies are needed to decipher the underlying pathway regulation.

Emerging Roles of Ephexins in Physiology and Disease

Dbl (B-cell lymphoma)-related guanine nucleotide exchange factors (GEFs), the largest family of GEFs, are directly responsible for the activation of Rho family GTPases and essential for a number of cellular events such as proliferation, differentiation and movement. The members of the Ephexin (Eph-interacting exchange protein) family, a subgroup of Dbl GEFs, initially were named for their interaction with Eph receptors and sequence homology with Ephexin1. Although the first Ephexin was identified about two decades ago, their functions in physiological and pathological contexts and regulatory mechanisms remained elusive until recently. Ephexins are now considered as GEFs that can activate Rho GTPases such as RhoA, Rac, Cdc42, and RhoG. Moreover, Ephexins have been shown to have pivotal roles in neural development, tumorigenesis, and efferocytosis. In this review, we discuss the known and proposed functions of Ephexins in physiological and pathological contexts, as well as their regulatory mechanisms.

The Rho guanine nucleotide exchange factor ARHGEF5 promotes tumor malignancy via epithelial-mesenchymal transition

Epithelial tumor cells often acquire malignant properties, such as invasion/metastasis and uncontrolled cell growth, by undergoing epithelial–mesenchymal transition (EMT). However, the mechanisms by which EMT contributes to malignant progression remain elusive. Here we show that the Rho guanine nucleotide exchange factor (GEF) ARHGEF5 promotes tumor malignancy in a manner dependent on EMT status. We previously identified ARHGEF5, a member of the Dbl family of GEFs, as a multifunctional mediator of Src-induced cell invasion and tumor growth. In the present study, ARHGEF5 was upregulated during tumor growth factor-β-induced EMT in human epithelial MCF10A cells, and promoted cell migration by activating the Rho-ROCK pathway. ARHGEF5 was necessary for the invasive and in vivo metastatic activity of human colorectal cancer HCT116 cells. These findings underscore the crucial role of ARHGEF5 in cell migration and invasion/metastasis. An in vivo tumorigenesis assay revealed that ARHGEF5 had the potential to promote tumor growth via the phosphatidylinositol 3-kinase (PI3K) pathway. However, ARHGEF5 was not required for tumor growth in epithelial-like human colorectal cancer HCT116 and HT29 cells, whereas the growth of mesenchymal-like SW480 and SW620 cells depended on ARHGEF5. Induction of EMT by tumor necrosis factor-α or Slug in HCT116 cells resulted in the dependence of tumor growth on ARHGEF5. In these mesenchymal-like cells, Akt was activated via ARHGEF5 and its activity was required for tumor growth. Analysis of a transcriptome data set revealed that the combination of ARHGEF5 upregulation and E-cadherin downregulation or Snail upregulation was significantly correlated with poor prognosis in patients with colorectal cancers. Taken together, our findings suggest that EMT-induced ARHGEF5 activation contributes to the progression of tumor malignancy. ARHGEF5 may serve as a potential therapeutic target in a subset of malignant tumors that have undergone EMT.