Fibronectin and colorectal cancer: signaling pathways and clinical implications

Identification of a novel cancer-associated fibroblasts gene signature based on bioinformatics analysis to predict prognosis and therapeutic responses in breast cancer

Cancer-associated fibroblasts (CAFs) provide suitable conditions for growth of tumor cell and facilitate tumor progression. Hence, we aimed to identify a CAFs-related gene signature associated with the prognosis of patients with breast cancer (BRCA). We downloaded datasets from Gene Expression Omnibus (GEO) and confirmed the correlation between CAFs infiltration scores and prognosis. By performing weighted gene co-expression network analysis (WGCNA) and Lasso Cox regression analysis, we constructed a four-gene (COL5A3, FN1, POSTN, and RARRES2) prognostic CAFs signature model. Based on the median risk score of CAFs, patients with BRCA were divided into high- and low-risk groups. Compared with low-risk group, patients in high-risk group exhibited a poor prognosis and limited response to immunotherapy. Furthermore, patients with high CAFs risk scores were found to have a detrimental prognosis due to the induction of immunosuppressive cell infiltration, resulting in an immunosuppressive tumor microenvironment. Importantly, we found that CAFs overexpressing FN1 and POSTN significantly promoted the wound healing and invasion ability of tumor cells in vitro validation. Taking together, we identified a four-gene prognostic CAFs signature, which was proven to be a reliable indicator for prognosis and therapeutic efficacy in patients with BRCA. This study provided evidence for novel CAFs-based stromal therapy.

Drug repurposing for targeting fibronectin in treatment of endometriosis and cancers

Increased concentrations of the fibronectin glycoprotein can cause ectopic tissue growth patients with endometriosis and the formation of various cancerous tumors. Furthermore, fibronectin binding to its receptors from the EDA (Extra Domain A) region contributes to promote tumorigenesis, metastasis and vasculogenesis. Thus, the EDA region can be considered a unique target for therapeutic intervention. Therefore, the present study used computational methods to identify the best fibronectin inhibitor(s) among FDA-approved drugs. First, docking-based virtual screening was performed using PyRx 0.8. Next, FDA-approved drugs that obtained favorable results in the docking phase were selected for further studies and analysis using molecular dynamics (MD) simulation. The preliminary findings of the virtual screening showed that 17 FDA-approved drugs (from 2471) had more favorable energy with their binding energy less than -9 kcal/mol. The MD simulation results of these 17 drugs showed that Avapritinib had a lower RMSD value and higher binding energy and hydrogen bonding than the other complexes in the EDA domain. Also, analyses related to the second structure changes displayed that Avapritinib in the EDA domain led to more changes in the second structure. According to the results, the anticancer drug Avapritinib forms a more stable complex with fibronectin than other FDA-approved drugs. Furthermore, this drug leads to more changes in the second EDA structure, which may have more serious potential for inhibiting EDA fibronectin.Communicated by Ramaswamy H. Sarma.

Zhuidu Formula suppresses the migratory and invasive properties of triple-negative breast cancer cells via dual signaling pathways of RhoA/ROCK and CDC42/MRCK

ETHNOPHARMACOLOGICAL RELEVANCE

Zhuidu Formula (ZDF) is composed of triptolide, cinobufagin and paclitaxel, which are the active ingredients of Tripterygium wilfordii Hook. F, dried toad skin and Taxus wallichiana var. chinensis (Pilg) Florin, respectively. Modern pharmacological studies show that triptolide, cinobufagin, and paclitaxel are well-known natural compounds that exert anti-tumor effects by interfering with DNA synthesis, inducing tumor cell apoptosis, and inhibiting the dynamic balance of the tubulin. However, the mechanism by which the three compounds inhibit triple-negative breast cancer (TNBC) metastasis is unknown.

OBJECTIVE

The objective of this investigation was to examine the inhibitory essences of ZDF on the metastasis of TNBC and elucidate its potential mechanism.

MATERIALS AND METHODS

Cell viability of triptolide (TPL), cinobufagin (CBF), and paclitaxel (PTX) on MDA-MB-231 cells was assessed employing a CCK-8 assay. The drug interactions of the three drugs on MDA-MB-231 cells were determined in vitro utilizing the Chou-Talalay method. MDA-MB-231 cells were identified for migration, invasion and adhesion in vitro through the implementation of the scratch assay, transwell assay and adhesion assay, respectively. The formation of cytoskeleton protein F-actin was detected by immunofluorescence assay. The expressions of MMP-2 and MMP-9 in the supernatant of the cells were determined by ELISA analysis. The Western blot and RT-qPCR were employed to explore the protein expressions associated with the dual signaling pathways of RhoA/ROCK and CDC42/MRCK. The anti-tumor efficacy of ZDF in vivo and its preliminary mechanism were investigated in the mouse 4T1 TNBC model.

RESULTS

The results demonstrated that ZDF could significantly reduce the viability of the MDA-MB-231 cell, and the combination index (CI) values of actual compatibility experimental points were all less than 1, demonstrating a favorable synergistic compatibility relationship. It was found that ZDF reduces RhoA/ROCK and CDC42/MRCK dual signaling pathways, which are responsible for MDA-MB-231cell migration, invasion, and adhesion. Additionally, there has been a significant reduction in the manifestation of cytoskeleton-related proteins. Furthermore, the expression levels of RhoA, CDC42, ROCK2, and MRCKβ mRNA and protein were down-regulated. ZDF significantly decreased the protein expressions of vimentin, cytokeratin-8, Arp2 and N-WASP, and inhibited actin polymerization and actomyosin contraction. Furthermore, MMP-2 and MMP-9 levels in the high-dose ZDF group were decreased by 30% and 26%, respectively. ZDF significantly reduced the tumor volume and protein expressions of ROCK2 and MRCKβ in tumor tissues without eliciting any perceptible alterations in the physical mass of the mice, and the reduction was more pronounced than that of the BDP5290 treated group.

CONCLUSION

The current investigation demonstrates that ZDF exhibits a proficient inhibitory impact on TNBC metastasis by regulating cytoskeletal proteins through the dual signaling pathways of RhoA/ROCK and CDC42/MRCK. Furthermore, the findings indicate that ZDF has significant anti-tumorigenic and anti-metastatic characteristics in breast cancer animal models.

Exosome Liberation by Human Neutrophils under L-Amino Acid Oxidase of Calloselasma rhodostoma Venom Action

L-Amino acid oxidase (LAAO) is an enzyme found in snake venom that has multifaceted effects, including the generation of hydrogen peroxide (H2O2) during oxidative reactions, leading to various biological and pharmacological outcomes such as apoptosis, cytotoxicity, modulation of platelet aggregation, hemorrhage, and neutrophil activation. Human neutrophils respond to LAAO by enhancing chemotaxis, and phagocytosis, and releasing reactive oxygen species (ROS) and pro-inflammatory mediators. Exosomes cellular nanovesicles play vital roles in intercellular communication, including immune responses. This study investigates the impact of Calloselasma rhodostoma snake venom-derived LAAO (Cr-LAAO) on human neutrophil exosome release, including activation patterns, exosome formation, and content. Neutrophils isolated from healthy donors were stimulated with Cr-LAAO (100 μg/mL) for 3 h, followed by exosome isolation and analysis. Results show that Cr-LAAO induces the release of exosomes with distinct protein content compared to the negative control. Proteomic analysis reveals proteins related to the regulation of immune responses and blood coagulation. This study uncovers Cr-LAAO's ability to activate human neutrophils, leading to exosome release and facilitating intercellular communication, offering insights into potential therapeutic approaches for inflammatory and immunological disorders.

FN1 mediated activation of aspartate metabolism promotes the progression of triple-negative and luminal a breast cancer

BACKGROUND

Breast cancer (BC) is regarded as one of the most common cancers diagnosed among the female population and has an extremely high mortality rate. It is known that Fibronectin 1 (FN1) drives the occurrence and development of a variety of cancers through metabolic reprogramming. Aspartic acid is considered to be an important substrate for nucleotide synthesis. However, the regulatory mechanism between FN1 and aspartate metabolism is currently unclear.

METHODS

We used RNA sequencing (RNA seq) and liquid chromatography-mass spectrometry to analyze the tumor tissues and paracancerous tissues of patients. MCF7 and MDA-MB-231 cells were used to explore the effects of FN1-regulated aspartic acid metabolism on cell survival, invasion, migration and tumor growth. We used PCR, Western blot, immunocytochemistry and immunofluorescence techniques to study it.

RESULTS

We found that FN1 was highly expressed in tumor tissues, especially in Lumina A and TNBC subtypes, and was associated with poor prognosis. In vivo and in vitro experiments showed that silencing FN1 inhibits the activation of the YAP1/Hippo pathway by enhancing YAP1 phosphorylation, down-regulates SLC1A3-mediated aspartate uptake and utilization by tumor cells, inhibits BC cell proliferation, invasion and migration, and promotes apoptosis. In addition, inhibition of FN1 combined with the YAP1 inhibitor or SLC1A3 inhibitor can effectively inhibit tumor growth, of which inhibition of FN1 combined with the YAP1 inhibitor is more effective.

CONCLUSION

Targeting the "FN1/YAP1/SLC1A3/Aspartate metabolism" regulatory axis provides a new target for BC diagnosis and treatment. This study also revealed that intratumoral metabolic heterogeneity plays an important role in the progression of different subtypes of breast cancer.

Cellular and Molecular Mechanisms of the Tumor Stroma in Colorectal Cancer: Insights into Disease Progression and Therapeutic Targets

Colorectal cancer (CRC) is a major health burden worldwide and is the third most common type of cancer. The early detection and diagnosis of CRC is critical to improve patient outcomes. This review explores the intricate interplay between the tumor microenvironment, stromal interactions, and the progression and metastasis of colorectal cancer. The review begins by assessing the gut microbiome's influence on CRC development, emphasizing its association with gut-associated lymphoid tissue (GALT). The role of the Wnt signaling pathway in CRC tumor stroma is scrutinized, elucidating its impact on disease progression. Tumor budding, its effect on tumor stroma, and the implications for patient prognosis are investigated. The review also identifies conserved oncogenic signatures (COS) within CRC stroma and explores their potential as therapeutic targets. Lastly, the seed and soil hypothesis is employed to contextualize metastasis, accentuating the significance of both tumor cells and the surrounding stroma in metastatic propensity. This review highlights the intricate interdependence between CRC cells and their microenvironment, providing valuable insights into prospective therapeutic approaches targeting tumor-stroma interactions.

Fibronectin promotes tumor angiogenesis and progression of non-small-cell lung cancer by elevating WISP3 expression via FAK/MAPK/ HIF-1α axis and activating wnt signaling pathway

BACKGROUND

Fibronectin, an extracellular matrix protein, has been reported to be associated with heterogeneous cancer stemness, angiogenesis and progression in multiple cancer types. However, the roles and the underlying mechanism of fibronectin on the progression NSCLC need to be further elucidated.

METHODS

Public dataset such as Kaplan-Meier Plotter was used to determine the prognostic significance of genes. The correlation of different protein expression in clinical and xenograft tissues was tested by immunohistochemistry experiment. Both in vitro and in vivo experiments were performed to determine the role of fibronectin on the tumor growth, metastasis, and angiogenesis in NSCLC. The activation of key signaling pathway under fibronectin was examined by WB assay. RNA-seq was applicated to screening the target gene of fibronectin. Rescue experiment was performed to confirm the role of target gene in fibronectin-mediated function in NSCLC. Finally, luciferase and CHIP assays were used to elucidate the mechanism by which fibronectin regulated the target gene.

RESULTS

Our results revealed that fibronectin was up-regulated in cancer tissues compared with the normal ones in NSCLC patients. Dish- coated fibronectin enhanced the tumor growth, metastasis, and angiogenesis of NSCLC in vitro and in vivo by promoting EMT and maintaining stemness of NSCLC cells. As expected, fibronectin activated FAK and its downstream MAPK/ERK signaling pathway. WISP3 was screened as a potential target gene of fibronectin. Interestingly, WISP3 effectively activated Wnt signaling pathway, and knockdown of WISP3 effectively blocked the influence of fibronectin on the migration, invasion and vascular structure formation potential of NSCLC cells. Our data also manifested that fibronectin elevated the transcription of WISP3 gene by promoting the binding of HIF-1α to the promoter region of WISP3 in NSCLC cells.

CONCLUSIONS

Our findings sketched the outline of the route for fibronectin exert its role in NSCLC, in which fibronectin activated downstream FAK and MAPK/ERK signaling pathways, and mediated the accumulation of HIF-1α. Then, HIF-1α enabled the transcription of WISP3, and subsequently promoted the activation of Wnt signaling pathway, and finally enhanced the tumor growth, metastasis, and angiogenesis in NSCLC.

The Matrix Reloaded—The Role of the Extracellular Matrix in Cancer

As the core component of all organs, the extracellular matrix (ECM) is an interlocking macromolecular meshwork of proteins, glycoproteins, and proteoglycans that provides mechanical support to cells and tissues. In cancer, the ECM can be remodelled in response to environmental cues, and it controls a plethora of cellular functions, including metabolism, cell polarity, migration, and proliferation, to sustain and support oncogenesis. The biophysical and biochemical properties of the ECM, such as its structural arrangement and being a reservoir for bioactive molecules, control several intra- and intercellular signalling pathways and induce cytoskeletal changes that alter cell shapes, behaviour, and viability. Desmoplasia is a major component of solid tumours. The abnormal deposition and composition of the tumour matrix lead to biochemical and biomechanical alterations that determine disease development and resistance to treatment. This review summarises the complex roles of ECM in cancer and highlights the possible therapeutic targets and how to potentially remodel the dysregulated ECM in the future. Furthering our understanding of the ECM in cancer is important as the modification of the ECM will probably become an important tool in the characterisation of individual tumours and personalised treatment options.

ECM Substrates Impact RNAi Localization at Adherens Junctions of Colon Epithelial Cells

The extracellular matrix (ECM) plays crucial roles in tissue homeostasis. Abnormalities in ECM composition are associated with pathological conditions, such as fibrosis and cancer. These ECM alterations are sensed by the epithelium and can influence its behavior through crosstalk with other mechanosensitive complexes, including the adherens junctions (AJs). We have previously shown that the AJs, through their component PLEKHA7, recruit the RNAi machinery to regulate miRNA levels and function. We have particularly shown that the junctional localization of RNAi components is critical for their function. Here, we investigated whether different ECM substrates can influence the junctional localization of RNAi complexes. To do this, we plated colon epithelial Caco2 cells on four key ECM substrates found in the colon under normal or pathogenic conditions, namely laminin, fibronectin, collagen I, and collagen IV, and we examined the subcellular distribution of PLEKHA7, and of the key RNAi components AGO2 and DROSHA. Fibronectin and collagen I negatively impacted the junctional localization of PLEKHA7, AGO2, and DROSHA when compared to laminin. Furthermore, fibronectin, collagen I, and collagen IV disrupted interactions of AGO2 and DROSHA with their essential partners GW182 and DGCR8, respectively, both at AJs and throughout the cell. Combinations of all substrates with fibronectin also negatively impacted junctional localization of PLEKHA7 and AGO2. Additionally, collagen I triggered accumulation of DROSHA at tri-cellular junctions, while both collagen I and collagen IV resulted in DROSHA accumulation at basal areas of cell-cell contact. Altogether, fibronectin and collagens I and IV, which are elevated in the stroma of fibrotic and cancerous tissues, altered localization patterns and disrupted complex formation of PLEKHA7 and RNAi components. Combined with our prior studies showing that apical junctional localization of the PLEKHA7-RNAi complex is critical for regulating tumor-suppressing miRNAs, this work points to a yet unstudied mechanism that could contribute to epithelial cell transformation.

Lnc-ABCA12-8 confers acquired resistance to gefitinib in non-small cell lung cancer by regulating the alternative splicing of fibronectin 1 in the IIICS region

Acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib, has dramatically impaired the clinical outcomes in non-small cell lung cancer (NSCLC) patients, but the mechanisms are still unclear in substantial cases. In our previous study, we demonstrated that a novel long non-coding RNA (lncRNA), lnc-ABCA12-8, was overexpressed in gefitinib-resistant NSCLC cells, but the exact function is unknown. In this study, we confirmed that lnc-ABCA12-8 was significantly upregulated both in NSCLC cell lines and the plasma samples of NSCLC patients with acquired resistance to gefitinib. Downregulation of lnc-ABCA12-8 could reverse gefitinib resistance both in vitro and in vivo. Mechanistically, lnc-ABCA12-8 interacted with alternative splicing factor/splicing factor 2 (ASF/SF2), promoted the binding of ASF/SF2 to the IIICS exon of fibronectin 1 (FN1) gene and enhanced the IIICS region inclusion during fibronectin 1 (FN1) alternative splicing, resulting in the upregulation of entire IIICS region, and enhanced cell proliferation, migration, invasion, and adhesion. Taken together, our study suggest that lnc-ABCA12-8 is involved in the acquired resistance to gefitinib, and may be a novel biomarker and therapeutic target for monitoring and overcoming gefitinib resistance in NSCLC.

FN1 is a prognostic biomarker and correlated with immune infiltrates in gastric cancers

Fibronectin 1 (FN1) is a glycoprotein found throughout the extracellular matrix that has a role in the onset and progression of cancer. However, its immune relationship with gastric cancer is still unclear. FN1 was systematically reviewed by Gene Expression Profiling Interactive Analysis (GEPIA), Linked Omics, Tumor IMmune Estimation Resource (TIMER), and Kaplan–Meier (KM) plotter analysis. The TIMER, GEPIA, TISIDB, and cBioPortal databases investigated the association of FN1 with tumor immune infiltration and validated using immunohistochemistry. We discovered that tumor tissue expresses FN1 at a higher level than neighboring tissue, and those genes coexpressed with FN1 have a poor prognosis. At the same time, we discovered that increased FN1 expression was related to immunological infiltration, particularly macrophage infiltration. Using immunohistochemistry, we discovered that FN1 expression was tightly connected to M2 macrophages. It can be concluded that FN1 can affect the immunological microenvironment and is a prognostic marker in gastric cancer.

The significance of PAK4 in signaling and clinicopathology: A review

P21-activated protein kinases (PAKs) are thought to be at the center of tumor signaling pathways. As a representative member of the group II PAK family, P21-activated protein kinase 4 (PAK4) plays an important role in the development of tumors, with several biological functions such as participating in oncogenic transformation, promoting cell division, resisting aging and apoptosis, regulating cytoskeleton and adhesion, as well as suppressing antitumor immune responses. PAK4 is also crucial in biological processes, including the occurrence, proliferation, survival, migration, invasion, drug resistance, and immune escape of tumor cells. It is closely related to poor prognosis and tumor-related pathological indicators, which have significant clinical and pathological significance. Therefore, this article offers a review of the structure, activation, and biological functions of PAK4 and its clinical and pathological importance. This overview should be of assistance for future research on PAK4 and tumors and provide new ideas for tumor treatment and prognostic evaluation of patients.

Targeted contrast agents and activatable probes for photoacoustic imaging of cancer

Photoacoustic (PA) imaging has emerged as a powerful technique for the high resolution visualization of biological processes within deep tissue. Through the development and application of exogenous targeted contrast agents and activatable probes that can respond to a given cancer biomarker, researchers can image molecular events in vivo during cancer progression. This information can provide valuable details that can facilitate cancer diagnosis and therapy monitoring. In this tutorial review, we provide a step-by-step guide to select a cancer biomarker and subsequent approaches to design imaging agents for in vivo use. We envision this information will be a useful summary to those in the field, new members to the community, and graduate students taking advanced imaging coursework. We also highlight notable examples from the recent literature, with emphasis on the molecular designs and their in vivo PA imaging performance. To conclude, we provide our outlook and future perspective in this exciting field.