FGF2 regulates proliferation, migration, and invasion of ECA109 cells through PI3K/Akt signalling pathway in vitro

Single-cell and bulk RNA-sequencing reveal SPP1 and CXCL12 as cell-to-cell communication markers to predict prognosis in lung adenocarcinoma

Lung adenocarcinoma (LUAD) generally presents as an immunosuppressive microenvironment. The characteristics of cell-to-cell communication in the LUAD microenvironment has been unclear. In this study, the LUAD bulk RNA-seq data and single-cell RNA-seq data were retrieved from public dataset. Differential expression genes (DEGs) between LUAD tumor and adjacent non-tumor tissues were calculated by limma algorithm, and then detected by PPI, KEGG, and GO analysis. Cell-cell interactions were explored using the single-cell RNA-seq data. Finally, the first 15 CytoHubba genes were used to establish related pathways and these pathways were used to characterize the immune-related ligands and their receptors in LUAD. Our analyses showed that monocytes or macrophages interact with tissue stem cells and NK cells via SPP1 signaling pathway and tissue stem cells interact with T and B cells via CXCL signaling pathway in different states. Hub genes of SPP1 participated in SPP1 signaling pathway, which was negatively correlated with CD4+ T cell and CD8+ T cell. The expression of SPP1 in LUAD tumor tissues was negatively correlated with the prognosis. While CXCL12 participated in CXCL signaling pathway, which was positively correlated with CD4+ T cell and CD8+ T cell. The role of CXCL12 in LUAD tumor tissues exhibits an opposite effect to that of SPP1. This study reveals that tumor-associated monocytes or macrophages may affect tumor progression. Moreover, the SPP1 and CXCL12 may be the critic genes of cell-to-cell communication in LUAD, and targeting these pathways may provide a new molecular mechanism for the treatment of LUAD.

ESOMIR: a curated database of biomarker genes and miRNAs associated with esophageal cancer

'Esophageal cancer' (EC) is a highly aggressive and deadly complex disease. It comprises two types, esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC), with Barrett's esophagus (BE) being the only known precursor. Recent research has revealed that microRNAs (miRNAs) play a crucial role in the development, prognosis and treatment of EC and are involved in various human diseases. Biological databases have become essential for cancer research as they provide information on genes, proteins, pathways and their interactions. These databases collect, store and manage large amounts of molecular data, which can be used to identify patterns, predict outcomes and generate hypotheses. However, no comprehensive database exists for EC and miRNA relationships. To address this gap, we developed a dynamic database named 'ESOMIR (miRNA in esophageal cancer) (https://esomir.dqweilab-sjtu.com)', which includes information about targeted genes and miRNAs associated with EC. The database uses analysis and prediction methods, including experimentally endorsed miRNA(s) information. ESOMIR is a user-friendly interface that allows easy access to EC-associated data by searching for miRNAs, target genes, sequences, chromosomal positions and associated signaling pathways. The search modules are designed to provide specific data access to users based on their requirements. Additionally, the database provides information about network interactions, signaling pathways and region information of chromosomes associated with the 3'untranslated region (3'UTR) or 5'UTR and exon sites. Users can also access energy levels of specific miRNAs with targeted genes. A fuzzy term search is included in each module to enhance the ease of use for researchers. ESOMIR can be a valuable tool for researchers and clinicians to gain insight into EC, including identifying biomarkers and treatments for this aggressive tumor. Database URL https://esomir.dqweilab-sjtu.com.

Role of Basic Fibroblast Growth Factor in Cancer: Biological Activity, Targeted Therapies, and Prognostic Value

Cancer is the leading cause of death worldwide; thus, it is necessary to find successful strategies. Several growth factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF, FGF2), and transforming growth factor beta (TGF-β), are involved in the main processes that fuel tumor growth, i.e., cell proliferation, angiogenesis, and metastasis, by activating important signaling pathways, including PLC-γ/PI3/Ca2+ signaling, leading to PKC activation. Here, we focused on bFGF, which, when secreted by tumor cells, mediates several signal transductions and plays an influential role in tumor cells and in the development of chemoresistance. The biological mechanism of bFGF is shown by its interaction with its four receptor subtypes: fibroblast growth factor receptor (FGFR) 1, FGFR2, FGFR3, and FGFR4. The bFGF–FGFR interaction stimulates tumor cell proliferation and invasion, resulting in an upregulation of pro-inflammatory and anti-apoptotic tumor cell proteins. Considering the involvement of the bFGF/FGFR axis in oncogenesis, preclinical and clinical studies have been conducted to develop new therapeutic strategies, alone and/or in combination, aimed at intervening on the bFGF/FGFR axis. Therefore, this review aimed to comprehensively examine the biological mechanisms underlying bFGF in the tumor microenvironment, the different anticancer therapies currently available that target the FGFRs, and the prognostic value of bFGF.

Circular RNA hsa_circ_0043688 serves as a competing endogenous RNA for microRNA-145-5p to promote the progression of Keloids via Fibroblast growth factor-2

Background

Keloids are benign fibroproliferative skin tumors. Circular RNA (circRNA) hsa_circ_0043688 has been exhibited to the freakishly expressed in keloid tissues. Here, we aimed to investigate the regulatory network of hsa_circ_0043688 in the pathological process of keloid.

Methods

Hsa_circ_0043688, microRNA‐145‐5p (miR‐145‐5p), and Fibroblast growth factor‐2 (FGF2) level were detected using RT‐qPCR. Cell viability, proliferation, apoptosis, invasion, and migration were investigated using Cell Counting Kit‐8 (CCK‐8), 5‐ethynyl‐2′‐deoxyuridine (EdU), flow cytometry, transwell, and wound healing assays, respectively. Western blot analysis of protein levels of FGF2, CyclinD1, Collagen I, and Collagen III. After the prediction of Circinteractome and Starbase, their interaction was verified based on a dual‐luciferase reporter and RIP assays.

Results

Increased hsa_circ_0043688 and FGF2, and decreased miR‐145‐5p in keloids samples and fibroblasts were found. Also, hsa_circ_0043688 absence hindered proliferation, invasion, migration, and boost apoptosis of keloid fibroblasts. In mechanism, hsa_circ_0043688 modulated FGF2 content via sponging miR‐145‐5p.

Conclusion

Hsa_circ_0043688 knockdown inhibited cell growth and metastasis of keloid fibroblasts via miR‐145‐5p/FGF2, providing a new mechanism to understand the keloid progression.

MicroRNA‑146a attenuates isoproterenol‑induced cardiac fibrosis by inhibiting FGF2

Cardiac fibrosis is a key factor of heart failure. Increasing evidence suggests that microRNAs (miRNAs/miRs) serve vital roles in the pathogenesis of cardiac fibrosis. The present study aimed to investigate the role of miR-146a-5p in isoproterenol (ISO)-induced cardiac fibrosis. Reverse transcription-quantitative PCR analysis demonstrated that miR-146a-5p expression was downregulated in ISO-treated rat heart tissue and ISO-induced cardiac fibroblasts (CFs). Conversely, the expression levels of basic fibroblast growth factor 2 (FGF2), collagen I and smooth muscle α-actin (α-SMA) were upregulated in ISO-treated rat cardiac tissue and CFs. Furthermore, viability and differentiation were inhibited in ISO-induced CFs transfected with miR-146a-5p mimics. Dual-luciferase reporter assay confirmed that miR-146a-5p targeted FGF2. Notably, FGF2 expression was suppressed following overexpression of miR-146a-5p, while FGF2 expression increased following miR-146a-5p knockdown. In addition, FGF2 knockdown suppressed the expression levels of FGF2, collagen I and α-SMA levels in CFs. Taken together, the results of the present study suggested that the miR-146a-5p/FGF2 pathway may be a novel therapy for cardiac fibrosis.

Circ_ARHGAP32 acts as miR-665 sponge to upregulate FGF2 to promote ox-LDL induced vascular smooth muscle cells proliferation and migration

BACKGROUND: Circular RNA (circRNA) is considered to be an important regulator of human diseases, including atherosclerosis (AS). However, the role of circ_ARHGAP32 in AS formation needs further confirmation. OBJECTIVE: To explore the role of circ_ARHGAP32 in AS formation. METHODS: Oxidized low density lipoprotein (ox-LDL) was used to treat vascular smooth muscle cells (VSMCs) to mimic AS cell models in vitro. The expression of circ_ARHGAP32, microRNA (miR)-665, and fibroblast growth factor 2 (FGF2) was analyzed by quantitative real-time PCR. VSMCs function was measured by EdU assay, cell counting kit 8 assay and transwell assay. Protein expression was determined using western blot analysis. Dual-luciferase reporter assay and RNA pull-down assay were performed to verify RNA interaction. RESULTS: Circ_ARHGAP32 was highly expressed in AS patients and ox-LDL-induced VSMCs. Knockdown of circ_ARHGAP32 repressed ox-LDL-induced proliferation and migration in VSMCs. Circ_ARHGAP32 sponged miR-665 to positively regulate FGF2. MiR-665 inhibitor reversed the regulation of sh-circ_ARHGAP32 on ox-LDL-induced VSMCs proliferation and migration. MiR-665 also had a suppressive effect on the proliferation and migration of ox-LDL-induced VSMCs, and this effect could be reversed by FGF2 overexpression. CONCLUSIONS: Circ_ARHGAP32 might be a potential target for AS treatment, which promoted ox-LDL-induced VSMCs proliferation and migration by regulating miR-665/FGF2 network.

CtBP2 interacts with TGIF to promote the progression of esophageal squamous cell cancer through the Wnt/β‑catenin pathway

C-terminal-binding protein 2 (CtBP2), a transcriptional co-repressor, plays a main role in tumorigenesis and in the development of multiple tumors. Transforming growth interacting factor (TGIF) is involved in a number of cellular signal transduction pathways and is related to tumor occurrence and development. In the present study, the proteins interacting with CtBP2 were identified and the mechanisms underlying the biological activity of CtBP2 in esophageal squamous cell carcinoma (ESCC) were investigated. The Search Tool for the Retrieval of Interacting Genes (STRING) database was used to search for known proteins interacting with CtBP2, and co-immunoprecipitation (Co-IP) assay was performed to validate the interactions. Reverse transcription-quantitative PCR (RT-qPCR), immunohistochemistry (IHC) and western blot analysis were performed to examine the expression levels of CtBP2 and TGIF in ESCC. The correlation between CtBP2 and TGIF was analyzed using Gene Expression Profiling Interactive Analysis (GEPIA) by Pearson's correlation analysis, and the co-localization of CtBP2 with TGIF in the ECA109 cells was identified using immunofluorescence staining. XAV939 treatment, CCK-8, 5-ethynyl-2′-deoxyuridine (EdU) staining, wound healing and Transwell assays were performed to investigate the signaling pathways involved in the biological activity of CtBP2 in ECA109 cells. According to the results obtained from STRING and Co-IP analysis, an interaction between CtBP2 and TGIF was indicated, and these proteins were co-localized in the nucleus. CtBP2 and TGIF mRNA and protein expression levels were robustly and simultaneously increased in both ESCC tissues and cell lines. There was a direct correlation between CtBP2 and TGIF expression levels in ESCC tissues, and both were significantly associated with metastasis and survival. The TGIF and CtBP2 expression levels were significantly increased or decreased simultaneously, in ECA109 cells transfected with LV-CtBP2 or sh-CtBP2, and vice versa. According to the results of CCK-8 assay, EdU staining and Transwell assay, CtBP2 promoted the proliferation, migration and invasion of ECA109 cells through the Wnt/β-catenin pathway. On the whole, the present study demonstrates that CtBP2 interacts with TGIF and promotes the malignant progression of ESCC through the Wnt/β-catenin pathway.

Zwitterionic hydrogel for sustained release of growth factors to enhance wound healing

Zwitterionic hydrogels outperform PEG hydrogels in delivering FGF2 for enhanced wound healing.

Effect of bFGF on fibroblasts derived from the golden snub-nosed monkey

Golden snub-nosed monkeys are endangered animals in China, and their cells have been demonstrated to be important as genetic resources and in applications for advancing biological research. Moreover, in primary research, basic fibroblast growth factor (bFGF) is used to promote the proliferation of fibroblasts to create abundant cells for cryopreservation. To further investigate the effect of bFGF on the efficiency of preservation of fibroblasts obtained from an endangered species, a fibroblast cell line was isolated from a dead golden snub-nosed monkey. Cell viability and mitochondrial membrane potential were assessed using CCK8 and JC-1 assay kits. The karyotype was analyzed by chromosomal microarray analysis, while RNA sequencing and gene expression analyses were performed to assess molecular changes in response to bFGF. Flow cytometry was used to characterize changes in cell surface markers in response to bFGF treatment. The results showed that cells maintained typical fibroblast morphology, while cell viability and mitochondrial membrane potential were not significantly affected between three and eight passages (p > 0.05). We also observed that the addition of bFGF promoted fibroblast proliferation and increased mitochondrial membrane potential. In addition, the bFGF treatment did not alter the normal karyotype of cells, downregulating fibroblast-associated genes and upregulating those associated with cell regulation, including those of the WNT, PI3K and MAPK pathways. The addition of bFGF also increased CD29, CD90, CD105, CD34 and CD44 expression while decreasing that of CD14 and HLA-DR at the protein level. Taken together, these results demonstrate that bFGF may upregulate the WNT, PI3K and MAPK pathways to promote cell proliferation while also increasing the expression of genes and surface markers associated with mesenchymal and hematopoietic cell linages.

Fibroblast growth factor 2 conjugated superparamagnetic iron oxide nanoparticles (FGF2-SPIONs) ameliorate hepatic stellate cells activation in vitro and acute liver injury in vivo

Liver diseases are the growing health problem with no clinically approved therapy available. Activated hepatic stellate cells (HSCs) are the key driver cells responsible for extracellular matrix deposition, the hallmark of liver fibrosis. Fibroblast growth factor 2 (FGF2) has shown to possess anti-fibrotic effects in fibrotic diseases including liver fibosis, and promote tissue regeneration. Among the fibroblast growth factor receptors (FGFRs), FGF2 interact primarily with FGFR1, highly overexpressed on activated HSCs, and inhibit HSCs activation. However, FGF2 poses several limitations including poor systemic half-life and stability owing to enzymatic degradation. The aim of this study is to improve the stability and half-life of FGF2 thereby improving the therapuetic efficacy of FGF2 for the treatment of liver fibrosis. We found that FGFR1-3 mRNA levels were overexpressed in cirrhotic human livers, while FGFR1c, 2c, 3c, 4 and FGF2 mRNA levels were overexpressed in TGFβ-activated HSCs (LX2 cells) and FGFR1 protein expression was highly increased in TGFβ-activated HSCs. Treatment with FGF2 inhibited TGFβ-induced HSCs activation, migration and contraction in vitro. FGF2 was conjugated to superparamagnetic iron-oxide nanoparticles (SPIONs) using carbodiimide chemistry, and the resulting FGF2-SPIONs were confirmed by dynamic light scattering (DLS), zeta potential, dot-blot analysis and Prussian Blue iron-staining. In vitro, treatment with FGF2-SPIONs evidenced increased therapeutic effects (attenuated TGFβ-induced HSCs activation, migration and contraction) of FGF2 in TGFβ-activated HSCs and ameliorated early liver fibrogenesis in vivo in acute carbon tetrachloride (CCl₄)-induced liver injury mouse model. In contrast, free FGF2 showed no significant effects in vivo. Altogether, this study presents a promising therapeutic approach using FGF2-SPIONs for the treatment of liver fibrosis.

Cellular processes involved in lung cancer cells exposed to direct current electric field

With the rapid breakthrough of electrochemical treatment of tumors, electric field (EF)-sensitive genes, previously rarely exploited, have become an emerging field recently. Here, we reported our work for the identification of EF-sensitive genes in lung cancer cells. The gene expression profile (GSE33845), in which the human lung cancer CL1-0 cells were treated with a direct current electric field (dcEF) (300 mV/mm) for 2 h, was retrieved from GEO database. Differentially expressed genes (DEGs) were acquired, followed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) and protein-protein interaction (PPI) analysis. Hub genes were acquired and analyzed by various tools including the Human Protein Atlas, Kaplan-Meier analysis, Cytoscape, FunRich, Oncomine and cBioPortal. Subsequently, three-dimensional protein models of hub genes were modeled by Modeller 9.20 and Rosetta 3.9. Finally, a 100 ns molecular dynamics simulation for each hub protein was performed with GROMACS 2018.2. A total of 257 DEGs were acquired and analyzed by GO, KEGG and PPI. Then, 10 hub genes were obtained, and the signal pathway analysis showed that two inflammatory pathways were activated: the FoxO signaling pathway and the AGE-RAGE signaling pathway. The molecular dynamic analysis including RMSD and the radius of gyration hinted that the 3D structures of hub proteins were built. Overall, our work identified EF-sensitive genes in lung cancer cells and identified that the inflammatory state of tumor cells may be involved in the feedback mechanism of lung cancer cells in response to electric field stimulation. In addition, qualified three-dimensional protein models of hub genes were also constructed, which will be helpful in understanding the complex effects of dcEF on human lung cancer CL1-0 cells.

Identification of microRNAs as novel biomarkers for esophageal squamous cell carcinoma: a study based on The Cancer Genome Atlas (TCGA) and bioinformatics

BACKGROUND

MicroRNAs (miRNAs) have played important roles in the regulation of gene expression in many cancers, but their roles in esophageal squamous cell carcinoma (ESCC) are still unclear. The aim of this study was to determine the potential ESCC-specific key miRNAs from a large sample dataset in The Cancer Genome Atlas (TCGA).

METHODS

Integrative bioinformatics analysis was used to identify key ESCC-specific miRNAs related to the ESCC patients' tumor histological grade and lymphatic metastasis from TCGA. Next, these key miRNA potential gene regulatory functions and relationships with ESCC patients' clinical characteristics and overall survival were analyzed. Finally, three key miRNAs were selected randomly and quantificational real-time polymerase chain reaction (qRT-PCR) was used to validate in 51 newly diagnosed ESCC patients' tissues samples (collected from Nov. 2017 to Feb. 2019, in Wuwei, China) whether the bioinformatics analyses results were reliable and valid. Two-tailed Student's t test, Pearson Chi-squared test and Kaplan-Meier survival analysis were used in this study.

RESULTS

Thirty-five ESCC-specific miRNAs from TCGA database were investigated (fold-change > 2.0, P < 0.05), and 28 participated in the miRNAs-mRNAs co-expression network construction, while 17 were related with ESCC patients' tumor histological grade, TNM stage, and lymphatic metastasis (P < 0.05). Meanwhile, six miRNAs (including miR-200b-3p, miR-31-5p, miR-15b-5p, miR-141-3p, miR-135b-5p, and miR-195-5p) were correlated with overall survival of ESCC patients (log-rank, P < 0.05). MiR-135b-5p, miR-15b-5p, and miR-195-5p were selected for verification of the expression levels in 51 ESCC patients' tissue samples by using qRT-PCR. We found that the fold-changes between qRT-PCR and TCGA were completely consistent. The results also suggested that miR-135b-5p, miR-15b-5p, and miR-195-5p were significantly correlated with tumor differentiation degrees (P < 0.05), miR-195-5p was significantly correlated with tumor TNM stage (P < 0.05), and miR-135b-5p was significantly correlated with lymph-node metastasis (P < 0.05). MiR-135b-5p, miR-15b-5p, and miR-195-5p expression levels, ESCC patient clinical features association analysis results and the aforementioned TCGA bioinformatics analyses were similar.

CONCLUSION

This study identified key ESCC-related miRNAs. The key miRNAs are worthy of further investigation as potential novel biomarkers for diagnosis, classification, and prognosis of ESCC.

MicroRNA-936 targets FGF2 to inhibit epithelial ovarian cancer aggressiveness by deactivating the PI3K/Akt pathway

Purpose

MicroRNA-936 (miR-936) was previously reported to be dysregulated and involved in the development of non-small cell lung cancer and glioma. However, the functional roles of miR-936 in epithelial ovarian cancer (EOC) remain unclear. In this study, we aimed to evaluate miR-936 expression in EOC and investigate its regulatory role in EOC cell behavior.

Methods

The expression of miR-936 in EOC was measured by RT-qPCR. Cell proliferation, apoptosis, migration, and invasion in vitro, as well as tumor growth in vivo, were determined by CCK-8, flow cytometry, migration and invasion assays, and xenograft models in nude mice, respectively. Bioinformatics analysis, luciferase reporter assays, RT-qPCR, and Western blot analysis were performed to investigate the relationship between miR-936 and fibroblast growth factor 2 (FGF2).

Results

miR-936 expression was significantly downregulated in EOC tissues and cell lines. Low miR-936 expression was found to be correlated with the tumor size, FIGO stage, and lymphatic metastasis in EOC patients. Functional experiments indicated that ectopic miR-936 expression suppressed EOC cell proliferation, migration, and invasion; promoted cell apoptosis; and decreased tumor growth in vivo. In addition, the FGF2 gene was verified to be a direct target of miR-936 in EOC cells. FGF2 expression levels were upregulated in EOC tissues and were inversely correlated with miR-936 expression. Furthermore, effects of FGF2 silencing were similar to those of miR-936 overexpression in EOC cells. Recovered FGF2 expression rescued the miR-936-induced inhibitory effects in EOC cells. Notably, miR-936 was able to deactivate the PI3K/Akt signaling pathway in EOC cells by regulating FGF2 both in vitro and in vivo.

Conclusion

Altogether, our findings provided initial evidence that miR-936 inhibits the aggressiveness of EOC cells in vitro and in vivo, at least partially, by targeting FGF2-mediated suppression of the PI3K/Akt pathway. Therefore, the miR-936/FGF2/PI3K/Akt pathway is a promising therapeutic target for the treatment of EOC patients.

Upregulation of sine oculis homeobox homolog 3 is associated with proliferation, invasion, migration, as well as poor prognosis of esophageal cancer

Esophageal cancer (EC) is a common cancer worldwide. Sine oculis homeobox homolog (SIX3) is a human transcription factor that regulates the progression of vertebrate eye and fetal forebrain. However, studies on the function of SIX3 in human tumorigenesis remain rare. In this study, we aim to evaluate the role and the significance of SIX3 in EC. The TCGA database and clinical samples were used to assess the expression of SIX3 in EC patients. The Kaplan-Meier method and Cox's proportional hazards model were performed to analyze the correlations between SIX3 expression and EC clinical outcomes. The expressions of SIX3 in EC cells were measured by quantitative reverse transcription PCR analysis. The cell proliferation was detected using cell counting kit-8 and colony formation assay. The migration and invasion capacity of EC cells were evaluated using wound healing and Transwell methods. Western blot assay was used to measure the alterations in some important protein expression levels in the PI3K/Akt signaling pathway. We found that SIX3 was highly expressed in the EC tissues and cells. In addition, high expression of SIX3 was related to poor survival. The knockdown of SIX3 significantly inhibited the proliferation, migration, and invasion of ECA109 cells. A similar pattern was also found in the proliferation and migration of SKGT-4 cell line. The expression levels of some key proteins in the PI3K/Akt signaling pathway were obviously decreased after cells were transfected with si-SIX3, possibly resulting in PI3K/AKT signaling inactivation. In addition, E-cadherin and N-cadherin showed some change. Collectively, the results shed light on a potentially promoting role of SIX3 in human EC. Thus, SIX3 might be considered a novel prognostic biomarker and therapeutic target for EC patients.

FABP5 regulates the proliferation of clear cell renal cell carcinoma cells via the PI3K/AKT signaling pathway

Clear cell renal cell carcinoma (ccRCC) has been associated with one of the highest mortality rates among all cancers. Fatty acid binding proteins (FABPs) are 14‑15 kDa proteins that are highly abundant in the cytosol of most tissues. FABP5, a member of the FABP family, has been observed to promote tumor cell growth in numerous cancer types. In order to investigate the function of FABP5 in ccRCC cells in the present study, RNA sequencing data from The Cancer Genome Atlas were analyzed to determine the expression levels of FABP5 in ccRCC patient samples. Survival and Cox regression analyses were performed to measure the association between FABP5 expression and clinicopathological features of patients with ccRCC. Subsequent in vitro experiments downregulated or overexpressed FABP5 in Caki‑1 and 786O ccRCC cells using lentiviral vectors to evaluate cell proliferation ability, and a xenograft transplantation model was established to examine the effect of FABP5 on tumorigenesis in vivo. The results demonstrated that FABP5 expression was significantly upregulated in samples from patients with ccRCC when compared with normal tissue samples. High FABP5 expression was also significantly correlated with tumor and metastasis classifications and predicted poor survival in patients with ccRCC. In ccRCC cells, silencing of FABP5 significantly inhibited cell proliferation, while overexpression of FABP5 promoted cell proliferation when compared to the respective controls. In addition, treatment with the phosphatidylinositol‑4,5‑bisphosphate 3‑kinase (PI3K)/AKT inhibitor, LY294002, attenuated the pro‑proliferative effects of exogenous FABP5 expression in Caki‑1 and 786O cells. This indicated that the PI3K/AKT signaling pathway may be partially involved in the FABP5‑mediated increase in ccRCC cell proliferation. Furthermore, FABP5 was observed to regulate tumor growth in nude mice in vivo. In conclusion, the results of the present study suggest that FABP5 may exert a pro‑proliferative role in ccRCC and may be associated with malignant progression and tumorigenesis.

Idiopathic pulmonary fibrosis (IPF) signaling pathways and protective roles of melatonin

Idiopathic pulmonary fibrosis (IPF) is characterized by the progressive loss of lung function due to tissue scarring. A variety of pro-inflammatory and pro-fibrogenic factors including interleukin‑17A, transforming growth factor β, Wnt/β‑catenin, vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factors, endotelin‑1, renin angiotensin system and impaired caveolin‑1 function are involved in the IPF pathogenesis. Current therapies for IPF have some limitations and this highlights the need for effective therapeutic agents to treat this fatal disease. Melatonin and its metabolites are broad-spectrum antioxidants that not only remove reactive oxygen and nitrogen species by radical scavenging but also up-regulate the expression and activity of endogenous antioxidants. Via these actions, melatonin and its metabolites modulate a variety of molecular pathways in different pathophysiological conditions. Herein, we review the signaling pathways involved in the pathophysiology of IPF and the potentially protective effects of melatonin on these pathways.

Down-regulation of C-terminal binding protein 2 (CtBP2) inhibits proliferation, migration, and invasion of human SHSY5Y cells in vitro

Neuroblastoma is the most common extracranial solid tumor in children and is responsible for ∼15% of pediatric cancer deaths. CtBP2 is a member of the CtBP family of proteins that functions as a transcription regulator and has been demonstrated to interact with the C-terminus of the adenoviral E1A oncoprotein. In this study, the expression of CtBP2 in the human neuroblastoma cell line SHSY5Y was down-regulated using lentiviral-mediated RNA interference. Down-regulation of CtBP2 inhibited the expression of c-myc, MMP2, and MMP9 proteins. Moreover, low expression of CtBP2 resulted in inhibited cell growth, proliferation, migration, and invasion, and the cell cycle was arrested at G2/M-phase. These results indicate that CtBP2 may be a potential target to suppress tumorigenesis in neuroblastoma.

Silencing of Ribosomal Protein L34 (RPL34) Inhibits the Proliferation and Invasion of Esophageal Cancer Cells

Ribosomal protein L34 (RPL34) belongs to the L34E family of ribosomal proteins and contains a zinc finger motif. Aberrant expression of RPL34 has been reported in several human malignancies. However, the precise role and potential underlying mechanisms of RPL34 in human esophageal cancer remain largely unknown. Thus, the objective of this study was to investigate the role of RPL34 in esophageal cancer progression. Our results showed that the expression of RPL34 at both the mRNA and protein levels was frequently upregulated in esophageal cancer cell lines. Knockdown of RPL34 efficiently inhibited esophageal cancer cell proliferation, migration, and invasion in vitro. Mechanistically, knockdown of RPL34 significantly downregulated the protein expression level of p-PI3K and p-Akt in esophageal cancer cells. Finally, knockdown of RPL34 attenuated tumor growth in nude mice. In conclusion, our study revealed that RPL34 functions as an oncogene that modulates the proliferation and metastasis of esophageal cancer cells, in part, by the inactivation of the PI3K/Akt signaling pathway. Thus, these findings suggest that RPL34 may serve as a potential therapeutic target for the treatment of esophageal cancer.