Vinculin expression in non-small cell lung cancer

Construction and analysis of protein-protein interaction network for esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a prevalent malignant tumor of the digestive tract. Clinical findings reveal that the five-year survival rate for mid-to late-stage ESCC patients is merely around 20 %, whereas those diagnosed at an early stage can achieve up to a 95 % survival rate. Consequently, early detection is paramount to improving ESCC patient survival. Protein markers are essential for diagnosing diseases, and the identification of new candidate proteins associated with ESCC through the protein-protein interaction (PPI) network is aimed for in this paper. The PPI network related to ESCC was constructed using protein data, comprising 2094 nodes and 19,660 edges. To assess the nodes' importance in the network, three metrics-degree centrality, betweenness centrality, and closeness centrality-were employed, leading to the identification of 81 key proteins. Subsequently, the biological significance of these proteins in the network was explored, combining biomedical knowledge from three perspectives: network, node, and cluster. The results demonstrated that 52 out of 81 key proteins were confirmed to be linked to ESCC. Among the remaining 29 unreported proteins, 18 displayed significant biological significance, indicating their potential as protein markers related to ESCC.

Topographical influence of electrospun basement membrane mimics on formation of cellular monolayer

Functional unit of many organs like lung, kidney, intestine, and eye have their endothelial and epithelial monolayers physically separated by a specialized extracellular matrix called the basement membrane. The intricate and complex topography of this matrix influences cell function, behavior and overall homeostasis. In vitro barrier function replication of such organs requires mimicking of these native features on an artificial scaffold system. Apart from chemical and mechanical features, the choice of nano-scale topography of the artificial scaffold is integral, however its influence on monolayer barrier formation is unclear. Though studies have reported improved single cell adhesion and proliferation in presence of pores or pitted topology, corresponding influence on confluent monolayer formation is not well reported. In this work, basement membrane mimic with secondary topographical cues is developed and its influence on single cells and their monolayers is investigated. We show that single cells cultured on fibers with secondary cues form stronger focal adhesions and undergo increased proliferation. Counterintuitively, absence of secondary cues promoted stronger cell-cell interaction in endothelial monolayers and promoted formation of integral tight barriers in alveolar epithelial monolayers. Overall, this work highlights the importance of choice of scaffold topology to develop basement barrier function in in vitro models.

miR‑491‑3p functions as a tumor suppressor in non‑small cell lung cancer by targeting fibroblast growth factor 5

The present study aimed to identify the function of miR-491-3p in regulating non-small cell lung cancer (NSCLC). Tumor tissues and adjacent normal tissues were collected from 43 patients with NSCLC. A549 and H1299 cells were transfected with microRNA (miR)-491-3p mimic, mimic negative control (NC), miR-491-3p inhibitor, inhibitor NC, pcDNA3.1-FGF5 vector and control vector. Cell counting kit-8 assay and Edu experiments were performed to assess cell viability and proliferation. Matrigel experiment, wound healing assay and flow cytometric analysis were performed to explore cell invasion, migration and apoptosis, respectively. A dual-luciferase reporter experiment was performed to identify the relationship between miR-491-3p and fibroblast growth factor 5 (FGF5). In vivo study was conducted by using nude mice. The miR-491-3p and FGF5 protein expression levels were investigated using reverse transcription-quantitative polymerase chain reaction and western blot analysis. In NSCLC tumor tissues, miR-491-3p was downregulated and FGF5 was upregulated (P<0.01). Low miR-491-3p expression and high FGF5 mRNA expression was associated with poor outcomes in patients, including advanced TNM stage and lymph node metastasis (P<0.05). upregulation of miR-491-3p suppressed viability, proliferation, invasion and migration of NSCLC cells; however, it promoted apoptosis (P<0.01). FGF5 was a target gene for miR-491-3p. miR-491-3p directly inhibited FGF5 expression. upregulation of FGF5 significantly reversed the inhibitory effects of miR-491-3p on malignant phenotypes of NSCLC cells (P<0.01). miR-491-3p overexpression suppressed the in vivo growth of NSCLC. Thus, it was identified that miR-491-3p functions as a tumor suppressor in NSCLC by directly targeting FGF5.

Cervical cancer-derived exosomal miR-663b promotes angiogenesis by inhibiting vinculin expression in vascular endothelial cells

BACKGROUND

Angiogenesis provides essential nutrients and oxygen for tumor growth and has become the main mechanism of tumor invasion and metastasis. Exosomes are nanoscale membrane vesicles containing proteins, lipids, mRNA and microRNA (miRNA), which mediate intercellular communication and play an important role in tumor progression. Accumulated evidence indicates that tumor-derived exosomal miRNAs participate in the tumor microenvironment and promote angiogenesis.

METHODS

Bioinformatic target prediction and dual luciferase reporter assays were performed to identify the binding site between miR-663b and the 3'-UTR of vinculin (VCL). VCL overexpression lentivirus and miR-663b overexpression/inhibition lentivirus were used to create a VCL overexpression model and miR-663b overexpression/inhibition model in-vitro. Immunohistochemistry (IHC) assays and western blot assays were used to detect protein expression. Exosome-cell cocultures, wound healing assays, tube formation assays and transwell assays were used to measure the migration and tube formation ability of vascular endothelial cells [human umbilical vein endothelial cells (HUVECs)]. siRNA targeted VCL was used to knockdown VCL.

RESULTS

In the present study, we found that miR-663b was elevated in cervical cancer tissue and exosomes. miR-663b could bind the 3'-UTR of VCL and inhibit its expression. VCL is downregulated in cervical cancer, and decreased VCL has a negative correlation with a high level of miR-663b. Further studies demonstrated that exosomes secreted by cervical cancer cells can deliver miR-663b to HUVECs and inhibit the expression of VCL, thereby promoting angiogenesis and tumor growth.

CONCLUSIONS

miR-663b derived from cancer cell exosomes acts as a driving factor for angiogenesis and a potential target of antiangiogenic therapy in cervical cancer. Our findings illustrated a new signaling pathway, including exosomes, miRNAs and target genes, which provides potential targets for antiangiogenic therapy.

Effect of Epigallocatechin-3-Gallate on EGFR Signaling and Migration in Non-Small Cell Lung Cancer

The epidermal growth factor receptor (EGFR) is one of the most well-studied molecular targets in non-small cell lung cancer (NSCLC) and tyrosine kinase inhibitors have been shown to be effective in the treatment of advanced NSCLC. Nevertheless, the efficacy of tyrosine kinase inhibitors could be compromised by additional mutations in EGFR and compensatory activations of other pathways. Epigallocatechin-3-gallate (EGCG), the main bioactive molecule in green tea, acts as a tyrosine kinase inhibitor toward cancer cells overexpressing EGFR (wild-type). However, little information has been reported on the effect of EGCG on EGFR with activating mutations. In this study, we evaluated the ability of EGCG to inhibit EGFR signaling activation in three different NSCLC cell lines containing wild-type EGFR or EGFR with additional mutations. The effect on proliferation, apoptosis, migration, and vinculin expression was then studied. Overall, our results demonstrate that EGCG polyphenol inhibits cell proliferation and migration in NSCLC cell lines, although with different efficacy and mechanisms. These data may be of interest for an evaluation of the use of EGCG as an adjunct to NSCLC therapies.

The Measurement and Analysis of Impedance Response of HeLa Cells to Distinct Chemotherapy Drugs

Electric cell–substrate impedance sensing exhibits a real-time and label-free feature to monitor the response of cells stimulated by various biochemical and mechanical signals. Alterations in the currents passing through the cell–electrode system characterize the impedance variations of cells. The impedance responses of HeLa cells under distinct chemotherapy drugs combine the effects of cell proliferation and cell–substrate adhesion. Optimal interdigitated electrodes were selected to explore the impedance responses of HeLa cells. Measurements of impedance of cells in response to three widely used chemotherapy drugs in clinical practice, namely cisplatin, doxorubicin, 5-fluorouracil, were performed. The results demonstrated that distinct impedance responses of HeLa cells to drugs were exhibited and a decrease in measured impedance was observed after drug treatment, accompanied by alterations in the distribution and intensity of the adhesion-related protein vinculin and the rate of cell proliferation. The link between the impedance profiles of HeLa cells and their biological functions was developed based on the circuit model. This study demonstrated the weights of cell proliferation and adhesion of HeLa cells under the treatments of DDP, DOX, and 5-FU, resulted in distinct impedance responses of cells, providing an impedance-based evaluation methodology for cervical cancer treatment.