NRP1 regulates radiation-induced EMT via TGF-β/Smad signaling in lung adenocarcinoma cells

Modulation of epithelial-mesenchymal transition by gemcitabine: Targeting ionizing radiation-induced cellular senescence in lung cancer cell

Ionizing radiation, a standard therapeutic approach for lung cancer, often leads to cellular senescence and the induction of epithelial-mesenchymal transition (EMT), posing significant challenges in treatment efficacy and cancer progression. Overcoming these obstacles is crucial for enhancing therapeutic outcomes in lung cancer management. This study investigates the effects of ionizing radiation and gemcitabine on lung cancer cells, with a focus on induced senescence, EMT, and apoptosis. Human-derived A549, PC-9, and mouse-derived Lewis lung carcinoma cells exposed to 10 Gy X-ray irradiation exhibited senescence, as indicated by morphological changes, β-galactosidase staining, and cell cycle arrest through the p53-p21 pathway. Ionizing radiation also promoted EMT via TGFβ/SMAD signaling, evidenced by increased TGFβ1 levels, altered EMT marker expressions, and enhanced cell migration. Gemcitabine, a first-line lung cancer treatment, was shown to enhance apoptosis in senescent cells caused by radiation. It inhibited cell proliferation, induced mitochondrial damage, and triggered caspase-mediated apoptosis, thus mitigating EMT in vitro. Furthermore, in vivo studies using a lung cancer mouse model revealed that gemcitabine, combined with radiation, significantly reduced tumor volume and weight, extended survival, and suppressed malignancy indices in irradiated tumors. Collectively, these findings demonstrate that gemcitabine enhances the therapeutic efficacy against radiation-resistant lung cancer cells, both by inducing apoptosis in senescent cells and inhibiting EMT, offering potential improvements in lung cancer treatment strategies.

The circadian clock gene, BMAL1, promotes radiosensitization in nasopharyngeal carcinoma by inhibiting the epithelial-to-mesenchymal transition via the TGF-β1/Smads/Snail1 axis

Acquired radio-resistance is thought to be one of the main causes of recurrent metastasis after failure of nasopharyngeal carcinoma (NPC) radiotherapy, which may be related to X-ray-induced epithelial-mesenchymal transition (EMT) activation. The circadian clock gene, BMAL1, has been shown to correlate with the sensitivity of NPCs to radiotherapy, but the specific mechanism has not been reported. NPC cells were irradiated by conventional fractionation to generate radiotherapy-resistant cells. NPC cells with BMAL1 gene stabilization/overexpression and interference were obtained by lentiviral transfection. Western blotting, colony formation analysis, cell counting kit-8 assays, wound-healing tests, Transwell assays, flow cytometry, the EDU method, nuclear plasma separation experiments, HE staining, immunohistochemical staining and TUNEL staining were performed to explore the influence and molecular mechanism of the circadian clock gene, BMAL1, on NPC-acquired radio-resistance and EMT through in vitro and in vivo experiments. The results indicated that there was a gradual downregulation of BMAL1 gene protein expression during the routine dose induction of radio-resistance in NPC cells. EMT activation was present in the radiation-resistant cell line 5-8FR, and was accompanied by the significant enhancement of proliferation, migration and invasion. The BMAL1 gene significantly increased the radiosensitivity of the radiation-resistant cell line 5-8FR and reversed the acquired radio-resistance of NPCs, which was accomplished by inhibiting the TGF-β1/Smads/Snail1 axis-mediated EMT.

The transcription factor GATA3 positively regulates NRP1 to promote radiation-induced pulmonary fibrosis

Radiation-Induced Pulmonary Fibrosis (RIPF) frequently arises as a delayed complication following radiation therapy for thoracic cancers, encompassing lung, breast, and esophageal malignancies. Characterized by a relentless and irreversible accumulation of extracellular matrix (ECM) proteins within the lung parenchyma, RIPF presents a significant clinical challenge. While the modulation of gene expression by transcription factors is a recognized aspect in various pathologies, their specific role in the context of RIPF has been less clear. This study elucidates that ionizing radiation prompts the translocation of the transcription factor GATA3 into the nucleus. This translocation facilitates GATA3's binding to the NRP1 promoter, thereby enhancing the transcription and subsequent translation of NRP1. Further investigations demonstrate that the TGF-β pathway agonist, SRI-011381, can mitigate the effects of NRP1 knockdown on epithelial-mesenchymal transition (EMT) and ECM deposition, suggesting a pivotal role of the GATA3/NRP1/TGF-β axis in the pathogenesis of RIPF. In conclusion, our findings not only underscore the critical involvement of GATA3 in RIPF but also highlight the GATA3/NRP1/TGF-β signaling pathway as a promising target for therapeutic intervention in RIPF management.

Effect of traditional Chinese medicine in osteosarcoma: Cross-interference of signaling pathways and potential therapeutic targets

Osteosarcoma (OS) has a high recurrence rate, disability rate, mortality and metastasis, it brings great economic burden and psychological pressure to patients, and then seriously affects the quality of life of patients. At present, the treatment methods of OS mainly include radiotherapy, chemotherapy, surgical therapy and neoadjuvant chemotherapy combined with limb salvage surgery. These treatment methods can relieve the clinical symptoms of patients to a certain extent, and also effectively reduce the disability rate, mortality and recurrence rate of OS patients. However, because metastasis of tumor cells leads to new complications, and OS cells become resistant with prolonged drug intervention, which reduces the sensitivity of OS cells to drugs, these treatments still have some limitations. More and more studies have shown that traditional Chinese medicine (TCM) has the characteristics of "multiple targets and multiple pathways," and can play an important role in the development of OS through several key signaling pathways, including PI3K/AKT, Wnt/β-catenin, tyrosine kinase/transcription factor 3 (JAK/STAT3), Notch, transforming growth factor-β (TGF-β)/Smad, nuclear transcription factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), nuclear factor E2-related factor 2 (Nrf2), Hippo/YAP, OPG/RANK/RANKL, Hedgehog and so on. In this paper, the signaling pathways of cross-interference between active ingredients of TCM and OS were reviewed, and the development status of novel OS treatment was analyzed. The active ingredients in TCM can provide therapeutic benefits to patients by targeting the activity of signaling pathways. In addition, potential strategies for targeted therapy of OS by using ferroptosis were discussed. We hope to provide a unique insight for the in-depth research and clinical application of TCM in the fields of OS growth, metastasis and chemotherapy resistance by understanding the signaling crosstalk between active ingredients in TCM and OS.

Overexpression of NRP1 is Associated with Poor Prognosis via Accelerating Immunosuppression in Head and Neck Squamous Cell Carcinoma

Background

Neuropilin-1 (NRP1) is a significant molecular structure that participates in many diseases progress including malignant tumors. However, its role in head and neck squamous cell carcinoma (HNSCC) remains to be uncovered. In this study, we determined the function of NRP1 as a crucial biomarker in proliferation, metastasis and immunosuppression in HNSCC.

Methods

We collected samples of normal tissues (n = 18) and HNSCC tissues (n = 202) for immunohistochemical staining of NRP1 and evaluated its correlation to clinical prognostic characteristics. Furthermore, we enrolled 37 HNSCC patients received immune checkpoint blockade (ICB) treatment with defined therapeutic effects records. The biological process, signal pathways, and immune infiltration relevance to NRP1 were analyzed utilized transcriptome data from The Cancer Genome Atlas (TCGA).

Results

The NRP1 protein expression was significantly upregulated in HNSCC tissue and was associated with T stage, N stage, histological differentiation, recurrence and NRP1 expression. The high expression of NRP1 indicated poor survival rate and was found to be an independent prognosis factor. Enrichment analysis showed that NRP1 was associated with cell adhesion, extracellular matrix organization, homophilic cell adhesion via plasma membrane in biological process and neuroactive ligand-receptor interaction, protein digestion and absorption, calcium signal pathways. Moreover, NRP1 mRNA level was found positively correlated to cancer associated fibroblast cells, Treg cells and macrophage/monocyte cells.

Conclusion

NRP1 might be likely to develop into a potential immunoregulation target as well as a predictive biomarker in HNSCC immune treatment.

Recent Advances in Transcription Factors Biomarkers and Targeted Therapies Focusing on Epithelial-Mesenchymal Transition

Transcription factors involve many proteins in the process of transactivating or transcribing (none-) encoded DNA to initiate and regulate downstream signals, such as RNA polymerase. Their unique characteristic is that they possess specific domains that bind to specific DNA element sequences called enhancer or promoter sequences. Epithelial-mesenchymal transition (EMT) is involved in cancer progression. Many dysregulated transcription factors-such as Myc, SNAIs, Twists, and ZEBs-are key drivers of tumor metastasis through EMT regulation. This review summarizes currently available evidence related to the oncogenic role of classified transcription factors in EMT editing and epigenetic regulation, clarifying the roles of the classified conserved transcription factor family involved in the EMT and how these factors could be used as therapeutic targets in future investigations.

Mechanisms of Biochanin A Alleviating PM2.5 Organic Extracts-Induced EMT of A549 Cells through the PI3K/Akt Pathway

Epithelial-mesenchymal transition (EMT) is an important step in tumor progression, which enables tumor cells to acquire migration and invasion characteristics. The aim of this study was to investigate the mechanism of biological biochanin A (BCA) in ameliorating fine particulate matter (PM2.5) lung injury. The results showed that PM2.5 could induce spindle-like changes in cell morphology, causing the ability of migration and invasion. However, they were significantly inhibited by BCA treatment (10/20/30 μm). After BCA treatment, the release and transcription of chemokine CXCL12 and its receptor gene CXCR4 were inhibited, and the release of growth inducer TGF-β1 was significantly reduced. In addition, BCA promoted the transcription of E-cadherin and β-catenin, inhibiting the expression of N-cadherin, vimentin, and fibronectin, and down-regulated the expression of MMP-2/9. We found that BCA effectively interfered with the PI3K/Akt signaling pathway activated by PM2.5. In conclusion, PM2.5 can induce EMT in lung cancer cells, and BCA may reverse this process by activating the PI3K/Akt signaling pathway.

LPAR5 confers radioresistance to cancer cells associated with EMT activation via the ERK/Snail pathway

BACKGROUND

Epithelial-to-mesenchymal transition (EMT) is a critical event contributing to more aggressive phenotypes in cancer cells. EMT is frequently activated in radiation-targeted cells during the course of radiotherapy, which often endows cancers with acquired radioresistance. However, the upstream molecules driving the signaling pathways of radiation-induced EMT have not been fully delineated.

METHODS

In this study, RNA-seq-based transcriptome analysis was performed to identify the early responsive genes of HeLa cells to γ-ray irradiation. EMT-associated genes were knocked down by siRNA technology or overexpressed in HeLa cells and A549 cells, and the resulting changes in phenotypes of EMT and radiosensitivity were assessed using qPCR and Western blotting analyses, migration assays, colony-forming ability and apoptosis of flow cytometer assays.

RESULTS

Through RNA-seq-based transcriptome analysis, we found that LPAR5 is downregulated in the early response of HeLa cells to γ-ray irradiation. Radiation-induced alterations in LPAR5 expression were further revealed to be a bidirectional dynamic process in HeLa and A549 cells, i.e., the early downregulating phase at 2 ~ 4 h and the late upregulating phase at 24 h post-irradiation. Overexpression of LPAR5 prompts EMT programing and migration of cancer cells. Moreover, increased expression of LPAR5 is significantly associated with IR-induced EMT and confers radioresistance to cancer cells. Knockdown of LPAR5 suppressed IR-induced EMT by attenuating the activation of ERK signaling and downstream Snail, MMP1, and MMP9 expression.

CONCLUSIONS

LPAR5 is an important upstream regulator of IR-induced EMT that modulates the ERK/Snail pathway. This study provides further insights into understanding the mechanism of radiation-induced EMT and identifies promising targets for improving the effectiveness of cancer radiation therapy.

A 25 Immune-Related Gene Pair Signature Predicts Overall Survival in Cervical Cancer

Mounting evidence suggests that the tumor microenvironment plays an important role in the occurrence and development of cancer, with immune system dysfunction being closely related to malignant cancers. We aimed to screen immune-related genes (IRGs) to generate an IRG pair (IRGP)-based prognostic signature for cervical cancer (CC). Datasets were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases and used as training and validation cohorts, respectively. Using the ImmPort database, IRGs in control and CC samples were compared, and differentially expressed genes were identified to construct an IRGP prognostic signature. Based on this analysis, 25 IRGPs were identified as important factors for the prognosis of CC. Univariate and multivariate Cox regression analyses further showed that the IRGP signature was an independent prognostic factor of overall survival. In summary, we successfully constructed an IRGP prognostic signature of CC, providing insights into immunotherapy for CC.

KLF8 is activated by TGF-β1 via Smad2 and contributes to ovarian cancer progression

Krüppel-like factor 8 (KLF8) is a transcription factor expressed abnormally in various cancer types and promotes oncogenic transformation. However, the role of KLF8 in ovarian cancer (OC) progression remains unclear. This study reports that transforming growth factor-β1 (TGF-β1)/Smad2/KLF8 axis regulates epithelial-mesenchymal transition (EMT) and contributes to OC progression. We analyzed the KLF8 expression in OC cells and tissues, wherein a significant overexpression of KLF8 was observed. Increased KLF8 expressions were correlated with higher cell proliferation, EMT, migration, and invasion and conferred poor clinical outcomes in OC patients. Overexpressed KLF8 increases F-actin polymerization and induces cytoskeleton remodeling of OC cells. Furthermore, a dissection of the molecular mechanism defined that TGF-β1 triggers KLF8 through the Smad2 pathway and regulates EMT. Pharmacological and genetic inhibition of Smad2 followed by TGF-β1 treatment failed to activate KLF8 expression and induction of EMT. Using promoter-luciferase reporter assays, we defined that upon TGF-β1 activation, phosphorylated Smad2 binds and promotes the KLF8 promoter activity, and knockdown of Smad2 inhibits KLF8 promoter activation. Together, these results demonstrate that TGF-β1 activates KLF8 expression by the Smad2 pathway, and KLF8 contributes to OC progression and may serve as a potential therapeutic strategy for treating OC patients.

Cancer-associated fibroblasts and their role in tumor progression

The stromal elements of a malignant tumor can promote cancer progression and metastasis. The structure of the tumor stroma includes connective tissue elements, blood vessels, nerves, and extracellular matrix (ECM). Some of the cellular elements of the tumor stroma are cancer-associated fibroblasts (CAFs). The origin and function of CAFs have been actively studied over the past thirty years. CAFs produce collagen, the main scaffold protein of the extracellular matrix. Collagen in the tumor stroma stimulates fibrosis, enhances the rigidity of tumor tissue, and disrupts the transmission of proliferation and differentiation signaling pathways. CAFs control tumor angiogenesis, cell motility, tumor immunogenic properties, and the development of resistance to chemo- and immunotherapy. As a result of metabolic adaptation of rapidly growing tumor tissue to the nutrients and oxygen deprivation, the main type of energy production in cells changes from oxidative phosphorylation to anaerobic glycolysis. These changes lead to sequential molecular alterations, including the induction of specified transcriptional factors that result in the CAFs activation. The molecular phenotype of activated CAFs is similar to fibroblasts activated during inflammation. In activated CAFs, alpha-smooth muscle actin (α-SMA) is synthetized de novo and various proteases and fibronectin are produced. Since CAFs are found in all types of carcinomas, these cells are potential targets for the development of new approaches for anticancer therapy. Some CAFs originate from resident fibroblasts of the organs invaded by the tumor, while others originate from epithelial tumor cells, which are undergoing an epithelial-mesenchymal transition (EMT). To date, many molecular and metabolic inducers of the EMT have been discovered including the transforming growth factor-beta (TGF-β), hypoxia, and inflammation. This review classifies modern concepts of molecular markers of CAFs, their functional features, and discusses the stages of epithelial-mesenchymal transition, and the potential of CAFs as a target for antitumor therapy.

Chelerythrine inhibits the progression of glioblastoma by suppressing the TGFB1-ERK1/2/Smad2/3-Snail/ZEB1 signaling pathway

AIMS

Glioblastoma (GBM) is the most common and aggressive intracranial tumor with poor prognosis. A large majority of clinical chemotherapeutic agents cannot achieve the desired therapeutic effect. Chelerythrine (CHE), a natural component with multitudinous pharmacological functions, has been proven to have outstanding antitumor effects in addition to antibacterial, anti-inflammatory, and hypotensive effects. However, the anti-GBM effect of CHE has not been reported to date. The purpose of this paper is to observe the anti-GBM effect of CHE and further explore the related mechanism.

MATERIALS AND METHODS

GBM cell lines (U251 and T98G) and BALB/c nude mice were used in the experiments. Methyl thiazolyl tetrazolium (MTT) and clone formation assays were applied to detect the viability, proliferation and stemness of GBM cells. Flow cytometry was utilized to identify the effect of CHE on GBM apoptosis. Scratch and Transwell experiments reflected the migration and invasion of cells. In vivo, xenograft tumors were implanted subcutaneously in nude mice. The progression of tumors was assessed by ultrasound and magnetic resonance imaging. Finally, western blot, bioinformatics, and immunohistochemistry experiments were used to explore the molecular mechanisms in depth.

KEY FINDINGS

In vitro tests showed that CHE inhibited the proliferation, stemness, migration, and invasion of GBM cells and induced apoptosis. In vitro, CHE was observed to restrain the progression of xenograft tumors. We eventually proved that the cytotoxicity of CHE was relevant to the TGFB1-ERK1/2/Smad2/3-Snail/ZEB1 signaling pathway.

SIGNIFICANCE

CHE inhibited GBM progression by inhibiting the TGFB1-ERK1/2/Smad2/3-Snail/ZEB1 signaling pathway and is a potential chemotherapeutic drug for GBM.

Epithelial-Mesenchymal Transition and Cancer Stem Cells

Epithelial-mesenchymal transition (EMT), a cellular phenotypic change from epithelial to mesenchymal-like features, is related to the resistance and metastasis of cancer stem cells (CSCs). Several signal transduction mechanisms induce EMT, which causes the gene expression alteration to induce the acquisition of resistance and metastasis in cancer. EMT is characterized with high gene expression of cadherin 2 (N-cadherin) and vimentin, and sparse cell-cell junction. The cells with EMT-phenotype have migration, metastasis and drug-resistance capacity, which are main characteristics of CSCs. It seems that the main population of CSCs exhibits EMT phenotype, whereas some populations consist of phenotypes other than EMT. In this chapter, EMT mechanism, phenotypic features of EMT and CSCs, signal transduction in EMT and CSCs, differences between EMT and CSCs, and the role of EMT in CSCs are described.

Reconciling two opposing effects of radiation therapy: stimulation of cancer cell invasion and activation of anti-cancer immunity

PURPOSE

The damage caused by radiation therapy to cancerous and normal cells inevitably leads to changes in the secretome profile of pro and anti-inflammatory mediators. The inflammatory response depends on the dose of radiation and its fractionation, while the inherent radiosensitivity of each patient dictates the intensity and types of adverse reactions. This review will present an overview of two apparently opposite reactions that may occur after radiation treatment: induction of an antitumor immune response and a protumoral response. Emphasis is placed on the molecular and cellular mechanisms involved.

CONCLUSIONS

By understanding how radiation changes the balance between anti- and protumoral effects, these forces can be manipulated to optimize radiation oncology treatments.

Effects of MLL5 and HOXA regulated by NRP1 on radioresistance in A549

Radiotherapy is widely used in the management of lung cancer, and physicians are aware that the effect of radiotherapy is dependent on radiosensitivity. Although a series of blockers and activators targeting molecules related to radioresistance have been developed as radiation sensitizers, compensatory mechanisms or drug resistance limits their clinical efficacy. The identification of a key molecule related to lung cancer cell radioresistance or an effective molecular target is a challenging but important problem in radiation oncology. A previous study found that neuropilin 1 (NRP1) is related to radioresistance in A549 cells and is associated with VEGF, PI3K-Akt, MAPK-ERK, P38, NF-κβ and TGF-β. Inhibition of NRP1 can increase the radiosensitivity of A549 cells. Therefore, NRP1 may be a molecular target for radiotherapy-sensitizing drugs in lung cancer. The present study investigated the key downstream genes of NRP1, verified their regulation and clarified their roles in regulating lung cancer radioresistance. NRP1 positively regulated the downstream homeobox genes (HOXs) HOXA6, HOXA9 and mixed lineage leukaemia 5 (MLL5) in addition to MLL5-regulated HOXA6 and HOXA9, but these genes did not regulate NRP1. MLL5, HOXA6 and HOXA9 levels were decreased in tumour tissues and positively correlated with NRP1. All of these genes were induced by ionizing radiation in vivo and in vitro. NRP1 expression was significantly lower in squamous cell carcinoma compared with that in adenocarcinoma, and lymph node metastasis occurred more often in patients with lung cancer with high MLL5 and NRP1 expression compared with patients with low MLL5 and NRP1 expression. Collectively, these data confirmed that NRP1 is associated with MLL5 and regulates radioresistance through HOXA6 and HOXA9.

Neuropilin-1 Interacts with Fibronectin-1 to Promote Epithelial-Mesenchymal Transition Progress in Gastric Cancer

Introduction

Neuropilin-1 (NRP1) binds to many ligands and co-receptors and affects cell survival and migration, which is essential for tumor progression. However, there are still largely unknowns about how NRP1 affects the epithelial-mesenchymal transition (EMT)-related malignant progression in gastric cancer.

Methods

We used TCGA to analyze the expression of NRP1 in gastric cancer and its impact on patient survival. In in vitro experiments, transwell, wound healing and colony formation assays were used to evaluate the effects of NRP1 and ginsenoside Rg3 on the invasion, migration and proliferation of gastric cancer cells. In in vivo experiments, we evaluated the overexpression and knockdown of NRP1 and the effect of ginsenoside Rg3 on tumor growth.

Results

We found that NRP1 is highly expressed in advanced gastric cancer and associated with poor prognosis. Knockdown of NRP1 expression can inhibit the proliferation and metastasis of gastric cancer cells. Mechanically. NRP1 interacts with fibronectin-1 (FN1) to promote the malignant progression of gastric cancer cells through ECM remodeling. In addition, we found that ginsenoside Rg3 can block the interaction of NRP1 and FN1 and inhibit the progression of gastric cancer.

Conclusion

Our study suggested that the interaction of NRP1 and FN1 is crucial for the malignant progression of gastric cancer. This may provide a new perspective and potential treatment methods for the treatment of gastric cancer.