Growth Factor Beta Signaling Pathway Research Articles

CircSMAD3 represses VSMC phenotype switching and neointima formation via promoting hnRNPA1 ubiquitination degradation.

Circular RNAs (circRNAs) are novel regulatory RNAs with high evolutionary conservation and stability, which makes them effective therapeutic agents for various vascular diseases. The SMAD family is a downstream mediator of the canonical transforming growth factor beta (TGF-β) signalling pathway and has been considered as a critical regulator in vascular injury. However, the role of circRNAs derived from the SMAD family members in vascular physiology remains unclear. In this study, we initially identified potential functional circRNAs originating from the SMAD family using integrated transcriptome screening. circSMAD3, derived from the SMAD3 gene, was identified to be significantly downregulated in vascular injury and atherosclerosis. Transcriptome analysis was conducted to comprehensively illustrate the pathways modulated by circRNAs. Functionally, circSMAD3 repressed vascular smooth muscle cell (VSMC) proliferation and phenotype switching in vitro evidenced by morphological assays, and ameliorated arterial injury-induced neointima formation in vivo. Mechanistically, circSMAD3 interacted with heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) within the nucleus, enhanced its interaction with E3 ligase WD repeat domain 76 to promote hnRNPA1 ubiquitination degradation, facilitated p53 pre-RNA splicing, activated the p53γ signalling pathway, and finally suppressed VSMC proliferation and phenotype switching. Our study identifies circSMAD3 as a novel epigenetic regulator that suppresses VSMC proliferation and phenotype switching, thereby attenuating vascular remodelling and providing a new circRNA-based therapeutic strategy for cardiovascular diseases.

The Regulation of MicroRNA-21 by Interleukin-6 and Its Role in the Development of Fibrosis in Endometriotic Lesions.

Endometriosis is one of the most common causes of chronic pelvic pain and infertility that affects 10% of women of reproductive age. It is currently defined as the presence of endometrial epithelial and stromal cells at ectopic sites; however, advances in endometriosis research have some authors believing that endometriosis should be re-defined as "a fibrotic condition in which endometrial stroma and epithelium can be identified". microRNAs (miRNAs) are regulatory molecules that potentially play a role in endometriotic lesion development. There is evidence that suggests that miRNAs, including microRNA-21 (miR-21), participate in fibrotic processes in different organs, including the heart, kidney, liver and lungs. The objective of this study was to understand the role of miR-21 and the mechanisms that can contribute to the development of fibrosis by determining how IL-6 regulates miR-21 expression and how this miRNA regulates the transforming growth factor beta (TGF-β) signaling pathway to promote fibrosis. We investigated the expression of miR-21 in the baboon and mouse model of endometriosis and its correlation with fibrosis. We demonstrated that inflammation and fibrosis are present at a very early stage of endometriosis and that the inflammatory environment in the peritoneal cavity, which includes interleukin 6 (IL-6), can regulate the expression of miR-21 in vitro and in vivo.

Effect of Different Dietary Iron Contents on Liver Transcriptome Characteristics in Wujin Pigs.

Iron is an important trace element that affects the growth and development of animals and regulates oxygen transport, hematopoiesis, and hypoxia adaptations. Wujin pig has unique hypoxic adaptability and iron homeostasis; however, the specific regulatory mechanisms have rarely been reported. This study randomly divided 18 healthy Wujin piglets into three groups: the control group, supplemented with 100 mg/kg iron (as iron glycinate); the low-iron group, no iron supplementation; and the high-iron group, supplemented with 200 mg/kg iron (as iron glycinate). The pre-feeding period was 5 days, and the formal period was 30 days. Serum was collected from empty stomachs before slaughter and at slaughter to detect changes in the serum iron metabolism parameters. Gene expression in the liver was analyzed via transcriptome analysis to determine the effects of low- and high-iron diets on transcriptome levels. Correlation analysis was performed for apparent serum parameters, and transcriptome sequencing was performed using weighted gene co-expression network analysis to reveal the key pathways underlying hypoxia regulation and iron metabolism. The main results are as follows. (1) Except for the hypoxia-inducible factor 1 (HIF-1) content (between the low- and high-iron groups), significant differences were not observed among the serum iron metabolic parameters. The serum HIF-1 content of the low-iron group was significantly higher than that of the high-iron group (p < 0.05). (2) Sequencing analysis of the liver transcriptome revealed 155 differentially expressed genes (DEGs) between the low-iron and control groups, 229 DEGs between the high-iron and control groups, and 279 DEGs between the low- and high-iron groups. Bioinformatics analysis showed that the HIF-1 and transforming growth factor-beta (TGF-β) signaling pathways were the key pathways for hypoxia regulation and iron metabolism. Four genes were selected for qPCR validation, and the results were consistent with the transcriptome sequencing data. In summary, the serum iron metabolism parameter results showed that under the influence of low- and high-iron diets, Wujin piglets maintain a steady state of physiological and biochemical indices via complex metabolic regulation of the body, which reflects their stress resistance and adaptability. The transcriptome results revealed the effects of low-iron and high-iron diets on the gene expression level in the liver and showed that the HIF-1 and TGF-β signaling pathways were key for regulating hypoxia adaptability and iron metabolism homeostasis under low-iron and high-iron diets. Moreover, HIF-1α and HEPC were the key genes. The findings provide a theoretical foundation for exploring the regulatory pathways and characteristics of iron metabolism in Wujin pigs.

Deciphering hepatoma cell resistance to tyrosine kinase inhibitors: insights from a Liver-on-a-Chip model unveiling tumor endothelial cell mechanisms.

Liver cancer represents a significant global burden in terms of cancer-related mortality, with resistance to anti-angiogenic drugs such as Sorafenib and Lenvatinib presenting a formidable challenge. Tumor angiogenesis, characterized by the formation of new blood vessels within tumors, plays a pivotal role in cancer progression and metastasis. Tumor endothelial cells, specialized endothelial cells lining tumor blood vessels, exhibit unique phenotypic and functional traits that drive aberrant vessel formation and contribute to therapy resistance. CD105, a cell-surface glycoprotein that is highly expressed on endothelial cells during angiogenesis, including tumor endothelial cells, regulates endothelial cell proliferation, migration, and vessel formation by modulating transforming growth factor-beta (TGF-β) signaling pathways. Elevated CD105 expression on tumor endothelial cells correlates with increased angiogenic activity and poor prognosis in cancer patients. Targeting CD105 with antibodies presents a promising strategy to inhibit tumor angiogenesis and disrupt tumor vasculature, offering potential therapeutic benefits by interfering with the tumor microenvironment and inhibiting its progression. This study investigates tumor angiogenesis through a three-dimensional (3D) microfluidic co-culture system incorporating endothelial cells and hepatocellular carcinoma (HCC) cells. The primary focus is on the role of CD105 expression within the liver tumor microenvironment and its contribution to increased chemoresistance. Additionally, this research examines the influence of CD105 expression on the efficacy of tyrosine kinase inhibitors (TKIs) and its pivotal function in facilitating angiogenesis in liver tumors. The proposed microfluidic chip model investigates liver cancer cell interactions within a microfluidic chip model designed to simulate aspects of liver tumor angiogenesis.

Understanding the Foreign Body Response via Single-Cell Meta-Analysis.

Foreign body response (FBR) is a universal reaction to implanted biomaterial that can affect the function and longevity of the implant. A few studies have attempted to identify targets for treating FBR through the use of single-cell RNA sequencing (scRNA-seq), though the generalizability of these findings from an individual study may be limited. In our study, we perform a meta-analysis of scRNA-seq data from all available FBR mouse studies and integrate these data to identify gene signatures specific to FBR across different models and anatomic locations. We identify subclusters of fibroblasts and macrophages that emerge in response to foreign bodies and characterize their signaling pathways, gene ontology terms, and downstream mediators. The fibroblast subpopulations enriched in the setting of FBR demonstrated significant signaling interactions in the transforming growth factor-beta (TGF-β) signaling pathway, with known pro-fibrotic mediators identified as top expressed genes in these FBR-derived fibroblasts. In contrast, FBR-enriched macrophage subclusters highly expressed pro-fibrotic and pro-inflammatory mediators downstream of tumor necrosis factor (TNF) signaling. Cell-cell interactions were additionally interrogated using CellChat, with identification of key signaling interactions enriched between fibroblasts and macrophages in FBR. By combining multiple FBR datasets, our meta-analysis study identifies common cell-specific gene signatures enriched in foreign body reactions, providing potential therapeutic targets for patients requiring medical implants across a myriad of devices and indications.

KLF10: a point of convergence in cancer cachexia.

Cancer-associated cachexia is a wasting syndrome entailing loss in body mass and a shortened life expectancy. There is currently no effective treatment to abrogate this syndrome, which leads to 20-30% of deaths in patients with cancer. While there have been advancements in defining signaling factors/pathways in cancer-induced muscle wasting, targeting the same in the clinic has not been as successful. Krüppel-like factor 10 (KLF10), a transcription factor implicated in muscle regulation, is regulated by the transforming growth factor-beta signaling pathway. This review proposes KLF10 as a potential convergence point of diverse signaling pathways involved in muscle wasting. KLF10 was discovered as a target of transforming growth factor-beta decades ago but more recently it has been shown that deletion of KLF10 rescues cancer-induced muscle wasting. Moreover, KLF10 has also been shown to bind key atrophy genes associated with muscle atrophy in vitro . There is an elevated need to explore targets in cachexia, which will successfully translate into the clinic. Investigating a convergence point downstream of multiple signaling pathways might hold promise in developing effective therapies for cachexia.

Genetic variants of the BMPR2 gene and their contribution to the development of pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a devastating disease characterized by a progressive increase in pressure in the pulmonary arteries. This leads to vascular remodeling and, eventually, right heart failure. Variants in the BMPR2 gene, which encodes the bone morphogenetic protein receptor type 2, are the most common genetic cause of hereditary and idiopathic PAH. These variants disrupt the transforming growth factor-beta (TGF-β) signaling pathway, triggering abnormal proliferation of pulmonary artery smooth muscle cells and apoptosis of endothelial cells. This results in complex vascular remodeling, characterized by thickening of the vascular walls, formation of plexiform lesions, and in situ thrombosis. Endothelial dysfunction also contributes to an imbalance between vasoconstrictors and vasodilators, exacerbating pulmonary hypertension. While current therapies aim to restore this balance, they have a limited impact on the underlying vascular remodeling. Emerging strategies seek to restore the functionality of BMPR2 variants or enhance their signaling through agonists and read-through molecules. Additionally, a higher penetrance of the disease has been observed in women carrying BMPR2 variants, suggesting an interaction with sex hormone metabolism. The research aims to understand the role of BMPR2 gene variants in the development of PAH and to explore emerging strategies to restore the functionality of these variants or enhance their signaling.

A heterogeneous tumor immune microenvironment of uncommon epidermal growth factor receptor mutant non-small cell lung cancer.

Common epidermal growth factor receptor (EGFR) mutations are usually not considered for immunotherapy in non-small cell lung cancer (NSCLC) due to poor efficacy. However, whether uncommon EGFR mutations are suitable for immunotherapy has not been thoroughly studied. Thus, we explored the tumor immune microenvironment (TME) features in uncommon EGFR mutant NSCLC. In this study, a total of 41 patients with EGFR mutations were included, the majority (85.4%) of whom were stage I. Among them, 22 patients harbored common mutations, while 19 patients presented with uncommon mutations. Compared with common mutations, uncommon mutations exhibited more infiltrating T cells and fewer M2 macrophages, upregulated expression of antigen processing and a presentation pathway. Unsupervised clustering based on the mIF profile identified two classes with heterogeneous TME in uncommon mutations. Class 1 featured the absence of PD-1+ cytotoxic T cell infiltration, and class 2 displayed a hotter TME because of the downregulated expression of hypoxia (p < 0.001), oxidative phosphorylation (p = 0.009), and transforming growth factor beta signaling (p = 0.01) pathways as well as increased expression of CTLA4 (p = 0.001) and PDCD1 (p = 0.004). The association of CTLA4 and PDCD1 with TME profiles was validated in a TCGA lung adenocarcinoma cohort with uncommon EGFR mutations. Our study reveals the distinct and heterogeneous TME features in uncommon EGFR mutant NSCLC.

DUSP5 regulated by YTHDF1-mediated m6A modification promotes epithelial-mesenchymal transition and EGFR-TKI resistance via the TGF-β/Smad signaling pathway in lung adenocarcinoma

BackgroundLung adenocarcinoma (LUAD) patients have a dismal survival rate because of cancer metastasis and drug resistance. The study aims to identify the genes that concurrently modulate EMT, metastasis and EGFR-TKI resistance, and to investigate the underlying regulatory mechanisms.MethodsCox regression and Kaplan–Meier analyses were applied to identify prognostic oncogenes in LUAD. Gene set enrichment analysis (GSEA) was used to indicate the biological functions of the gene. Wound-healing and Transwell assays were used to detect migratory and invasive ability. EGFR-TKI sensitivity was evaluated by assessing the proliferation, clonogenic survival and metastatic capability of cancer cells with treatment with gefitinib. Methylated RNA immunoprecipitation (MeRIP) and RNA immunoprecipitation (RIP) analyses established the level of m6A modification present on the target gene and the protein’s capability to interact with RNA, respectively. Single-sample gene set enrichment (ssGSEA) algorithm used to investigate levels of immune cell infiltration.ResultsOur study identified dual-specificity phosphatase 5 (DUSP5) as a novel and powerful predictor of adverse outcomes for LUAD by using public datasets. Functional enrichment analysis found that DUSP5 was positively enriched in EMT and transforming growth factor-beta (TGF-β) signaling pathway, a prevailing pathway involved in the induction of EMT. As expected, DUSP5 knockdown suppressed EMT via inhibiting the canonical TGF-β/Smad signaling pathway in in vitro experiments. Consistently, knockdown of DUSP5 was first found to inhibit migratory ability and invasiveness of LUAD cells in in vitro and prevent lung metastasis in in vivo. DUSP5 knockdown re-sensitized gefitinib-resistant LUAD cells to gefitinib, accompanying reversion of EMT progress. In LUAD tissue samples, we found 14 cytosine-phosphate-guanine (CpG) sites of DUSP5 that were negatively associated with DUSP5 gene expression. Importantly, 5′Azacytidine (AZA), an FDA-approved DNA methyltransferase inhibitor, restored DUSP5 expression. Moreover, RIP experiments confirmed that YTH N6-methyladenosine RNA binding protein 1 (YTHDF1), a m6A reader protein, could bind DUSP5 mRNA. YTHDF1 promoted DUSP5 expression and the malignant phenotype of LUAD cells. In addition, the DUSP5-derived genomic model revealed the two clusters with distinguishable immune features and tumor mutational burden (TMB).ConclusionsBriefly, our study discovered DUSP5 which was regulated by epigenetic modification, might be a potential therapeutic target, especially in LUAD patients with acquired EGFR-TKI resistance.Graphical

Multiple Endocrine Neoplasia Type 1 Regulates TGFβ-Mediated Suppression of Tumor Formation and Metastasis in Melanoma.

Over the past few decades, the worldwide incidence of cutaneous melanoma, a malignant neoplasm arising from melanocytes, has been increasing markedly, leading to the highest rate of skin cancer-related deaths. While localized tumors are easily removed by excision surgery, late-stage metastatic melanomas are refractory to treatment and exhibit a poor prognosis. Consequently, unraveling the molecular mechanisms underlying melanoma tumorigenesis and metastasis is crucial for developing novel targeted therapies. We found that the multiple endocrine neoplasia type 1 (MEN1) gene product Menin is required for the transforming growth factor beta (TGFβ) signaling pathway to induce cell growth arrest and apoptosis in vitro and prevent tumorigenesis in vivo in preclinical xenograft models of melanoma. We further identified point mutations in two MEN1 family members affected by melanoma that led to proteasomal degradation of the MEN1 gene product and to a loss of TGFβ signaling. Interestingly, blocking the proteasome degradation pathway using an FDA-approved drug and RNAi targeting could efficiently restore MEN1 expression and TGFβ transcriptional responses. Together, these results provide new potential therapeutic strategies and patient stratification for the treatment of cutaneous melanoma.

Platelet membrane biomimetic nanoparticle-targeted delivery of TGF-β1 siRNA attenuates renal inflammation and fibrosis

The progression of renal fibrosis to end-stage renal disease (ESRD) is significantly influenced by transforming growth factor-beta (TGF-beta) signal pathway. This study aimed to develop nanoparticles (PMVs@PLGA complexes) with platelet membrane camouflage, which can transport interfering RNA to target and regulate the TGF-β1 pathway in damaged renal tissues. The aim is to reduce the severity of acute kidney injury and to reduce fibrosis in chronic kidney disease. Hence, we formulated PMVs@TGF-β1-siRNA NP complexes and employed them for both in vitro and in vivo therapy. From the experimental findings we know that the PMVs@siRNA NPs could effectively target the kidneys in unilateral ureteral obstruction (UUO) mice and ischemia/reperfusion injury (I/R) mice. In animal models of treatment, PMVs@siRNA NP complexes effectively decreased the expression of TGF-β1 and mitigated inflammation and fibrosis in the kidneys by blocking the TGF-β1/Smad3 pathway. Therefore, these PMVs@siRNA NP complexes can serve as a promising biological delivery system for treating kidney diseases.

Computational Exploration of Naturally Occurring Flavonoids as TGF-β Inhibitors in Breast Cancer: Insights from Docking and Molecular Dynamics Simulations and In-vitro Cytotoxicity Study.

Breast cancer is a global health concern, demanding innovative treatments. Targeting the Transforming Growth Factor-beta (TGF-β) signaling pathway, pivotal in breast cancer, is a promising approach. TGF-β inhibits proliferation via G1 phase cell cycle arrest, acting as a suppressor initially, but in later stages, it promotes progression by enhancing motility, invasiveness, and metastasis formation. This study explores naturally occurring flavonoids' interactions with TGF-β. Using molecular docking against the protein's crystal structure (PDB Id: 1PY5), Gossypin showed the highest docking score and underwent molecular dynamics simulation, revealing complex flexibility and explaining how flavonoids impede TGF-β signaling in breast cancer. ADMET predictions adhered to Lipinski's rule of Five. Insights into flavonoid-TGF-β binding offer a novel angle for breast cancer treatment. Flavonoids having a good docking score like gossypin, morin, luteolin and taxifolin shown potent cytotoxic effect on breast cancer cell line, MCF-7. Understanding these interactions could inspire flavonoid-based therapies targeting TGF-β to halt breast cancer growth. These findings pave the way for personalized, targeted breast cancer therapies, offering hope against this formidable disease.

A RARE CASE OF LOEYS–DIETZ SYNDROME: THE IMPORTANCE OF DIAGNOSIS IN PATIENTS UNDERGOING CARDIOVASCULAR SURGERY

Abstract Background Loeys–Dietz syndrome (LDS) is a rare autosomal dominant genetic disorder of connective tissue, characterised by a broad spectrum of craniofacial, vascular (arterial tortuosity and aneurysms) and skeletal clinical signs. Four subtypes have been described, related to mutations in genes encoding for components of the transforming growth factor beta signalling pathway (TGFBR1, TGFBR2, SMAD2, SMAD3, TGFB2 and TGFB3). Diagnosis is based on the evaluation of clinical manifestations and family history. Therefore, many radiologists remain unfamiliar with the imaging and clinical findings in LDS. The Case 75–year–old woman, history of surgery for ruptured gastric a. aneurysm and ectasia of visceral arterial vessels. One year onset of worsening dyspnoea and asthenia, at echocardiography (ECOCG) severe aortic insufficiency has been detected and patient underwent aortic valve replacement with bioprosthesis. Cardiac surgery was complicated by aortic dissection (Stanford A; DeBakey I type) treated with replacement of ascending aorta and anterior hemiarch with tubular prosthesis. On that occasion a family diagnosis of SMAD3 gene mutation was made (both sister and nephew typed), compatible with Loeys–Dietz syndrome type 3. At the control angioTC evidence of proximal and distal anastomosis in order, in the absence of signs of periprosthetic leak. At ECOCG (FE 55%), thickened septum with marked postcardiac dyskinesia. No abnormality detected on ECG. Due to persistence of dyspnoea on mild exertion (NYHA class III) and reduced tolerance to orthostatism, cardiac rehabilitation program was undertaken on an outpatient basis for three months, providing an improvement in exertion tolerance (NYHA II) and a benefit on functional autonomy. LDS is a multisystem connective tissue disorder that is associated with a high burden of complications, a correct diagnosis will allow clinicians to appropriately establish the best therapeutic strategy, especially in cardiac surgery, taking into account the intraoperative and perioperative potential risks.

Discovery of PELATON links to the INHBA gene in the TGF-β pathway in colorectal cancer using a combination of bioinformatics and experimental investigations

Colorectal cancer (CRC) is a major worldwide health issue, with high rates of both occurrence and mortality. Dysregulation of the transforming growth factor-beta (TGF-β) signaling pathway is recognized as a pivotal factor in CRC pathogenesis. Notably, the INHBA gene and long non-coding RNAs (lncRNAs) have emerged as key contributors to CRC progression. The aim of this research is to explore the immunological roles of INHBA and PELATON in CRC through a combination of computational predictions and experimental validations, with the goal of enhancing diagnostic and therapeutic strategies. In this study, we utilized bioinformatics analyses, which involved examining differential gene expression (DEG) in the TCGA-COAD dataset and exploring the INHBA gene in relation to the TGF-β pathway. Additionally, we analyzed mutations of INHBA, evaluated the microenvironment and tumor purity, investigated the INHBA's connection to immune checkpoint inhibitors, and measured its potential as an immunotherapy target using the TIDE score. Utilizing bioinformatics analyses of the TCGA-COAD dataset beside experimental methodologies such as RT-qPCR, our investigation revealed significant upregulation of INHBA in CRC. As results, our analysis of the protein-protein interaction network associated with INHBA showed 10 interacting proteins that play a role in CRC-associated processes. We observed a notable prevalence of mutations within INHBA and explored its correlation with the response to immune checkpoint inhibitors. Our study highlights INHBA as a promising target for immunotherapy in CRC. Moreover, our study identified PELATON as a closely correlated lncRNA with INHBA, with experimental validation confirming their concurrent upregulation in CRC tissues. Thus, these findings highlight the importance of INHBA and PELATON in driving CRC progression, suggesting their potential utility as diagnostic and prognostic biomarkers. By integrating computational predictions with experimental validations, this research enhances our understanding of CRC pathogenesis and uncovers prospects for personalized therapeutic interventions.

Abstract PO2-28-03: E-Cigarette Aerosol Exposure: Unraveling the Nexus of Autophagy, Cancer Stem Cells, and EMT in Breast Cancer Metastasis

Abstract Electronic cigarettes (E-cigs) have emerged as a significant public health concern due to their increasing popularity. These products have been associated with various harmful effects on human health. In the United States, breast cancer is the most diagnosed cancer among women, and its recurrence and metastasis are primary contributors to morbidity and mortality. Two critical factors in cancer progression are Epithelial-mesenchymal transition (EMT) and Cancer stem-like cells (CSCs), both of which play pivotal roles in metastasis. As a result, targeting the signaling pathways involved in these processes has become a promising avenue for cancer therapy. Autophagy, a cellular process, has dual roles in cancer development depending on the cancer type and stage. Given these considerations, our hypothesis centers on disrupting the EMT-mediated metastatic cascade in breast cancer by targeting autophagy in Cancer Stem Cells (CSCs). To investigate this hypothesis, we conducted experiments using mouse breast epithelial cells (HC11) and Triple-negative mouse breast cancer cells (4T1) exposed to E-cig aerosol at the air-liquid interphase (ALI) for 1 hr followed by a 24 hr recovery period. Our findings indicate that exposure to E-cig aerosols led to a decrease in epithelial markers (E-Cadherin and β-catenin) and an increase in mesenchymal markers (N-Cadherin and Vimentin) in HC11 cells. This suggests that normal cells may acquire characteristics associated with solitary migration. Furthermore, we observed significant changes in the levels of autophagy-related proteins (LC3B, Beclin-1, ATG12, and ATG16) and upregulation of stem cell markers (OCT4, SOX2, NANOG, KLF4, and c-MYC) in response to E-cig aerosol exposure, both in HC11 and 4T1 cells. Additionally, these alterations extended to changes in the expression of genes associated with the Transforming Growth Factor-beta (TGF-β) signaling pathway, known to play a potential role in promoting EMT. Our results provide a deeper understanding of the interplay between EMT, CSCs, and the autophagy process in the context of ALI exposure in normal and cancer cells. This underscores the need for further research into the shared molecular mechanisms of these three processes to identify common therapeutic targets that can simultaneously affect them. Citation Format: Shilpa Thota, Rizwana Begum, Naveen Chintalaramulu, Biplov Sapkota, Abhishek Pandit. E-Cigarette Aerosol Exposure: Unraveling the Nexus of Autophagy, Cancer Stem Cells, and EMT in Breast Cancer Metastasis [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-28-03.

SMAD4-Dependent Signaling Pathway Involves in the Pathogenesis of TGFBR2-Related CE-like Phenotype.

(1) Background: Our previous data indicated that disturbance of the Transforming Growth Factor beta (TGFB) signaling pathway via its Type-2 Receptor (TGFBR2) can cause a Corneal Ectasia (CE)-like phenotype. The purpose of this study is to elucidate whether the SMAD4-dependent signaling pathway is involved in the TGFBR2-related CE-like pathogenesis. (2) Methods: Smad4 was designed to be conditionally knocked out from keratocytes. Novel triple transgenic mice, KerartTA; Tet-O-Cre; Smad4flox/flox (Smad4kera-cko), were administered with doxycycline (Dox). Optical Coherence Tomography (OCT) was performed to examine Central Corneal Thickness (CCT), Corneal Radius, Anterior Chamber and CE-like phenotype and compared to the littermate Control group (Smad4Ctrl). (3) Results: The OCT revealed normal cornea in the Smad4Ctrl and a CE-like phenotype in the Smad4kera-cko cornea, in which the overall CCT in Smad4kera-cko was thinner than that of Smad4Ctrl at P42 (n = 6, p < 0.0001) and showed no significant difference when compared to that in Tgfbr2kera-cko. Furthermore, the measurements of the Anterior Chamber and Corneal Radius indicated a substantial ectatic cornea in the Smad4kera-cko compared to Smad4Ctrl. The H&E staining of Smad4kera-cko mimics the finding in the Tgfbr2kera-cko. The positive immunostaining of cornea-specific marker K12 indicating the cell fate of cornea epithelium remained unchanged in Smad4kera-cko and the Proliferating Cell Nuclear Antigen (PCNA) immunostaining further indicated an enhanced proliferation in the Smad4kera-cko. Both immunostainings recapitulated the finding in Tgfbr2kera-cko. The Masson's Trichrome staining revealed decreased collagen formation in the corneal stroma from both Smad4kera-cko and Tgfbr2kera-cko. The collagen type 1 (Col1a1) immunostaining further confirmed the reduction in collagen type 1 formation in Smad4kera-cko. (4) Conclusions: The aforementioned phenotypes in the Smad4kera-cko strain indicated that the SMAD4-dependent signaling pathway is involved in the pathogenesis of the CE-like phenotype observed in Tgfbr2kera-cko.

Abstract 34: Improving CAR T cell efficacy in pancreatic cancer using an in vivo CRISPR Cas9 screen

Abstract Introduction: Chimeric antigen receptor (CAR) T cell therapy has demonstrated remarkable success in the treatment of certain hematologic malignancies. However, efficacy against solid tumors has remained limited and is associated with relatively low T cell persistence. Here, we perform an in vivo CAR T cell CRISPR screen in pancreatic adenocarcinoma using a curated guide library to identify genes that enhance CAR T cell persistence in vivo. Material and Methods: The Mario library consists of 1180 total guide RNAs targeting 135 genes that have been shown to modulate T cell functions in other models. To generate Mario-CART cells, primary human T cells were transduced with two lentiviral vectors, the first encoding an anti-mesothelin CAR and the second containing a fixed guide targeting the TCR alpha gene constant region (TRAC) as well as the Mario library. Mario-CART cells were transduced at low MOI, expanded in vitro and selected for loss of CD3 expression using magnetic selection, to enrich for cells that had a successful gene-edited event. Purified Mario-CART cells were intravenously injected into NSG mice bearing subcutaneous pancreatic adenocarcinoma (ASPC1). Tumor and spleen were harvested 2 or 4 weeks after Mario-CART injection, and engrafted T cells were isolated by CD45 positive selection. Genomic DNA was prepared from retrieved cells and illumina sequencing was used to evaluate guide abundance to identify gene knockouts that had been enriched after tumor exposure in vivo. Results: The transcription factor, GATA3, was consistently identified as the most enriched hit across two donor T cells when Mario-CART was recovered at the 2-week timepoint. When compared to control or a depleted hit, GATA3 KO CAR showed early improvements in tumor clearance in vivo. However, relapse occurred at similar timepoints across groups. At the 4-week timepoint, the most enriched guides comprised a different set, including genes involved in transforming growth factor beta and JAK-STAT signaling pathways as well as T cell trafficking. In vivo anti-tumor control data are being collected. Conclusions: Our findings highlight the dynamic nature of CART-tumor interactions. Gene knockouts that confer enhancements may change over time with varying context (such as in vitro vs in vivo conditions). It may be difficult to identify single gene knockouts that enhance CAR-T cell functions across different conditions and over time, but rather it may be necessary to exert more dynamic functional control of CAR T cells to enhance their function in different settings. Citation Format: Tamina Kienka, Felix Korell, Nelson Knudsen, Kathleen Yates, Andi Cheng, Debattama Sen, Marcela Maus, Robert Manguso. Improving CAR T cell efficacy in pancreatic cancer using an in vivo CRISPR Cas9 screen [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 34.

Electric field induced the changes in structure and function of human transforming growth factor beta receptor type I: from molecular dynamics to docking

The transforming growth factor beta (TGF-β) signaling pathway is believed to play essential roles in several physiological activities, including cancer. TGF-β receptor type I (TBR-I) is a key membrane receptor protein in the TGF-β signaling pathway, which relates to many intracellular biological effects. In recent years, cold atmospheric plasma (CAP) has been found to have promising prospects in selective anticancer therapy and has confirmed its essential role in the TGF-β signaling pathway. However, the ambiguous effect of CAP-induced electric field (EF) on TBR-I still limits the application of CAP in clinical therapy. Molecular dynamics is applied to assess the effect of EF on the structure of the extracellular domain of TBR-I using a series of indicators and methods, and then we discuss the ligand binding ability of TBR-I. Results show that moderate EF intensities’ structural restraints may contribute to the structural stability and ligand-binding ability of TBR-I, but an EF higher than 0.1 V/nm will be harmful. What’s more, EF induces a change in the docking interface of TBR-I, showing the conformation and position of special sequences of residues decide the ligand binding surface. The relevant results suggest that CAP-induced EF plays a crucial role in receptor-receptor interaction and provides significant guidelines for EF-related anticancer therapy. Communicated by Ramaswamy H. Sarma

The H9N2 avian influenza virus increases APEC adhesion to oviduct epithelia by viral NS1 protein-mediated activation of the TGF-β pathway.

H9N2 avian influenza is a low-pathogenic avian influenza circulating in poultry and wild birds worldwide and frequently contributes to chicken salpingitis that is caused by avian pathogenic Escherichia coli (APEC), leading to huge economic losses and risks for food safety. Currently, how the H9N2 virus contributes to APEC infection and facilitates salpingitis remains elusive. In this study, in vitro chicken oviduct epithelial cell (COEC) model and in vivo studies were performed to investigate the role of H9N2 viruses on secondary APEC infection, and we identified that H9N2 virus enhances APEC infection both in vitro and in vivo. To understand the mechanisms behind this phenomenon, adhesive molecules on the cell surface facilitating APEC adhesion were checked, and we found that H9N2 virus could upregulate the expression of fibronectin, which promotes APEC adhesion onto COECs. We further investigated how fibronectin expression is regulated by H9N2 virus infection and revealed that transforming growth factor beta (TGF-β) signaling pathway is activated by the NS1 protein of the virus, thus regulating the expression of adhesive molecules. These new findings revealed the role of H9N2 virus in salpingitis co-infected with APEC and discovered the molecular mechanisms by which the H9N2 virus facilitates APEC infection, offering new insights to the etiology of salpingitis with viral-bacterial co-infections.IMPORTANCEH9N2 avian influenza virus (AIV) widely infects poultry and is sporadically reported in human infections. The infection in birds frequently causes secondary bacterial infections, resulting in severe symptoms like pneumonia and salpingitis. Currently, the mechanism that influenza A virus contributes to secondary bacterial infection remains elusive. Here we discovered that H9N2 virus infection promotes APEC infection and further explored the underlying molecular mechanisms. We found that fibronectin protein on the cell surface is vital for APEC adhesion and also showed that H9N2 viral protein NS1 increased the expression of fibronectin by activating the TGF-β signaling pathway. Our findings offer new information on how AIV infection promotes APEC secondary infection, providing potential targets for mitigating severe APEC infections induced by H9N2 avian influenza, and also give new insights on the mechanisms on how viruses promote secondary bacterial infections in animal and human diseases.

Metabolic Dysfunction-Associated Steatotic Liver Disease in a Dish: Human Precision-Cut Liver Slices as a Platform for Drug Screening and Interventions.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing healthcare problem with limited therapeutic options. Progress in this field depends on the availability of reliable preclinical models. Human precision-cut liver slices (PCLSs) have been employed to replicate the initiation of MASLD, but a comprehensive investigation into MASLD progression is still missing. This study aimed to extend the current incubation time of human PCLSs to examine different stages in MASLD. Healthy human PCLSs were cultured for up to 96 h in a medium enriched with high sugar, high insulin, and high fatty acids to induce MASLD. PCLSs displayed hepatic steatosis, characterized by accumulated intracellular fat. The development of hepatic steatosis appeared to involve a time-dependent impact on lipid metabolism, with an initial increase in fatty acid uptake and storage, and a subsequent down-regulation of lipid oxidation and secretion. PCLSs also demonstrated liver inflammation, including increased pro-inflammatory gene expression and cytokine production. Additionally, liver fibrosis was also observed through the elevated production of pro-collagen 1a1 and tissue inhibitor of metalloproteinase-1 (TIMP1). RNA sequencing showed that the tumor necrosis factor alpha (TNFα) signaling pathway and transforming growth factor beta (TGFβ) signaling pathway were consistently activated, potentially contributing to the development of inflammation and fibrosis. In conclusion, the prolonged incubation of human PCLSs can establish a robust ex vivo model for MASLD, facilitating the identification and evaluation of potential therapeutic interventions.