Downregulation and growth inhibitory role of FHL1 in lung cancer

Overexpression of FHL1 suppresses papillary thyroid cancer proliferation and progression via inhibiting Wnt/β-catenin pathway

PURPOSE

The four and a half LIM domain protein 1 (FHL1) has been found to act as a tumor suppressor in several cancers. However, the clinical and functional significance, as well as underlying molecular mechanisms of FHL1 in papillary thyroid cancer (PTC) are largely unknown.

METHODS

Bioinformatics analyses, qRT-PCR and Western blotting were used to investigate the expression of FHL1 in PTC. Cell proliferation was measured using CCK8, Edu, colony formation, and flow cytometry assays. Cell migration and invasion were examined by wound healing and Transwell assays. qRT-PCR, Western blot, immunofluorescence and Top/Fop reporter assays were performed to assess the underlying mechanisms.

RESULTS

FHL1 expression was significantly downregulated in PTC. FHL1 downregulation negatively correlated with stage, T classification, and N classification of the patients. The downregulation of FHL1 is associated with poor prognosis. Overexpression of FHL1 inhibited PTC cells' proliferation, invasion, migration and Wnt/β-catenin pathway activity. LiCl partially restored the inhibitory effects of FHL1 on aggressive phenotypes and Wnt/β-catenin pathway activity of PTC cells.

CONCLUSION

FHL1 is downregulated in PTC and its expression is associated with better clinical outcomes for patients with the disease. FHL1 acts as a tumor suppressor via, at least partially, suppressing Wnt/β-catenin pathway.

Long non-coding RNA Small Nucleolar RNA Host Gene 4 ameliorates cigarette smoke-induced proliferation, apoptosis, inflammation, and airway remodeling in alveolar epithelial cells through the modulation of the mitogen-activated protein kinase signaling pathway via the microRNA-409-3p/Four and a Half LIM Domains 1 axis

The long non-coding RNA (lncRNA) Small Nucleolar RNA Host Gene 4 (SNHG4) has been demonstrated to be significantly downregulated in various inflammatory conditions, yet its role in chronic obstructive pulmonary disease (COPD) remains elusive. This study aims to elucidate the biological function of SNHG4 in COPD and to unveil its potential molecular targets. Our findings reveal that both SNHG4 and Four and a Half LIM Domains 1 (FHL1) were markedly downregulated in COPD, whereas microRNA-409-3p (miR-409-3p) was upregulated. Importantly, SNHG4 exhibited a negative correlation with inflammatory markers in patients with COPD, but a positive correlation with forced expiratory volume in 1s percentage (FEV1%). SNHG4 distinguished COPD patients from non-smokers with high sensitivity, specificity, and accuracy. Overexpression of SNHG4 ameliorated cigarette smoke extract (CSE)-mediated inflammation, apoptosis, oxidative stress, and airway remodeling in 16HBE bronchial epithelial cells. These beneficial effects of SNHG4 overexpression were reversed by the overexpression of miR-409-3p or the silencing of FHL1. Mechanistically, SNHG4 competitively bound to miR-409-3p, mediating the expression of FHL1, and consequently improving inflammation, apoptosis, oxidative stress, and airway remodeling in 16HBE cells. Additionally, SNHG4 regulated the miR-409-3p/FHL1 axis to inhibit the activation of the mitogen-activated protein kinase (MAPK) pathway induced by CSE. In a murine model of COPD, knockdown of SNHG4 exacerbated CSE-induced pulmonary inflammation, apoptosis, and oxidative stress. In summary, our data affirm that SNHG4 mitigates pulmonary inflammation, apoptosis, and oxidative damage mediated by COPD through the regulation of the miR-409-3p/FHL1 axis.

Low FHL1 expression indicates a good prognosis and drug sensitivity in ovarian cancer

Chemotherapy resistance is the main reason for the poor prognosis of ovarian cancer (OC). FHL1 is an important tumour regulator, but its relationship with the prognosis, drug resistance, and tumour microenvironment of OC is unknown. Immunohistochemistry was used to determine FHL1 expression in OC. Kaplan‒Meier plotter was used for survival analysis. The value of gene expression in predicting drug resistance was estimated using the area under the curve (AUC). Bivariate correlation was used to determine the coexpression of two genes. Functional cluster and pathway enrichment were used to uncover hidden signalling pathways. The relationship between gene levels and the tumour microenvironment was visualised through the ggstatsplot and pheatmap packages. The mRNA and protein levels of FHL1 were downregulated in 426 and 100 OC tissues, respectively. Low FHL1 expression was correlated with good progression-free survival (PFS), postprogression survival, and overall survival (OS) in 1815 OC patients, and was further confirmed to be associated with good OS by immunohistochemistry in 152 OC tissues. Furthermore, FHL1 was downregulated in drug-sensitive tissues, while its high expression predicted drug resistance (AUC > 0.65). Mechanistically, FHL1 was coexpressed with FLNC, CAV1, PPP1R12B, and FLNA at the mRNA and protein levels in 558 and 174 OC tissues, respectively, and their expression was downregulated in OC. Additionally, very strong coexpression of FHL1 with the four genes was identified in at least 23 different tumours. Low expression of the four genes was associated with good PFS, and the combination of FHL1 with the four genes provided better prognostic power. Meanwhile, the expression of all five genes was strongly and positively associated with the abundance of macrophages. Low FHL1 expression acts as a favourable factor in OC, probably via positive coexpression with FLNC, CAV1, PPP1R12B, and FLNA.

Biological and clinical significance of the glypican-3 gene in human lung adenocarcinoma: An in silico analysis

Glypican-3 (GPC3), a membrane-bound heparan sulfate proteoglycan, has long been found to be dysregulated in human lung adenocarcinomas (LUADs). Nevertheless, the function, mutational profile, epigenetic regulation, co-expression profile, and clinicopathological significance of the GPC3 gene in LUAD progression are not well understood. In this study, we analyzed cancer microarray datasets from publicly available databases using bioinformatics tools to elucidate the above parameters. We observed significant downregulation of GPC3 in LUAD tissues compared to their normal counterparts, and this downregulation was associated with shorter overall survival (OS) and relapse-free survival (RFS). Nevertheless, no significant differences in the methylation pattern of GPC3 were observed between LUAD and normal tissues, although lower promoter methylation was observed in male patients. GPC3 expression was also found to correlate significantly with infiltration of B cells, CD8+, CD4+, macrophages, neutrophils, and dendritic cells in LUAD. In addition, a total of 11 missense mutations were identified in LUAD patients, and ~1.4% to 2.2% of LUAD patients had copy number amplifications in GPC3. Seventeen genes, mainly involved in dopamine receptor-mediated signaling pathways, were frequently co-expressed with GPC3. We also found 11 TFs and 7 miRNAs interacting with GPC3 and contributing to disease progression. Finally, we identified 3 potential inhibitors of GPC3 in human LUAD, namely heparitin, gemcitabine and arbutin. In conclusion, GPC3 may play an important role in the development of LUAD and could serve as a promising biomarker in LUAD.

Immortalization-upregulated protein promotes pancreatic cancer progression by regulating NPM1/FHL1-mediated cell-cycle-checkpoint protein activity

Immortalization-upregulated protein (IMUP) plays a vital role in cell proliferation and tumor progression. However, its role in pancreatic ductal adenocarcinoma (PDAC) remains unclear. Here, we select IMUP as an alternative gene based on GeneChip analysis of clinical PDAC tissues and transcriptome data from The Cancer Genome Atlas. IMUP expression is upregulated in PDAC tumor tissues. Moreover, high IMUP expression correlates with poor prognosis, while IMUP depletion inhibits PDAC cell proliferation and colony formation capacity in vitro, and decreases xenograft tumor growth in vivo. IMUP downregulation leads to cell-cycle arrest in the S phase. IMUP knockdown increases the expression of four-and-a-half LIM domain protein 1 (FHL1), which regulates the phosphorylation of cell division cycle 25A (CDC25A) by cycle checkpoint kinase 1 (CHK1) and promotes cytoplasmic distribution of CDC25A by interaction with 14-3-3ξ. Furthermore, FHL1 knockdown restores the effects induced by IMUP depletion. Liquid chromatography tandem mass spectrometry and immunoprecipitation analysis further show that IMUP interacts directly with nucleophosmin (NPM1) and enhances its stability. DNA methylation sequencing shows that FHL1 promoter methylation decreases when IMUP is downregulated. Overexpression of NPM1 can increase the methylation level of FHL1, thereby decreasing its expression. Our study provides a novel perspective on IMUP/NPM1/FHL1-mediated cell-cycle arrest by regulating CDC25A phosphorylation in PDAC. These findings may provide a new therapeutic target for PDAC.

Potential roles of exosomes in the initiation and metastatic progression of lung cancer

Lung cancer (LC) incidence and mortality continue to increase annually worldwide. LC is insidious and readily metastasizes and relapses. Except for its early diagnosis and surgical resection, there is no effective cure for advanced metastatic LC, and the prognosis remains dismal. Exosomes, a class of nano-sized extracellular vesicles produced by healthy or diseased cells, are coated with a bilayer lipid membrane and contain various functional molecules such as proteins, lipids, and nucleic acids. They can be used for intracellular or intercellular signaling or the transportation of biological substances. A growing body of evidence supports that exosomes play multiple crucial roles in the occurrence and metastatic progression of many malignancies, including LC. The elucidation of the potential roles of exosomes in the initiation, invasion, and metastasis of LC and their underlying molecular mechanisms may contribute to improved early diagnosis and treatment.

Downregulation of miR-144 blocked the proliferation and invasion of nerve cells in Hirschsprung disease by regulating Transcription Factor AP 4 (TFAP4)

BACKGROUND

Hirschsprung's disease (HSCR) is characterized by a dysfunction of enteric neural crest cells (ENCCs) proliferation, migration and premature apoptosis during embryonic development, resulting in aganglionic colon. Our aim is to explore the role of miR-144 with its target gene Transcription Factor AP 4 (TFAP4) in nerve cells in HSCR.

METHODS

The relative expression levels of miR-144 in HSCR colon samples were detected by quantitative real-time PCR (RT-qPCR). Western blot assays were conducted to investigate the TFAP4 protein expressing level. The interaction of miR-144 and TFAP4 was predicted with bioinformatics analysis and examined with luciferase reporter assays. Overexpression or knockdown of miR-144 and TFAP4 in 293T and SH-SY5Y cell lines was applied. Cell proliferation, migration and invasion were detected by CCK-8 assays, Transwell migration and invasion assays. Cell cycle and apoptosis was examined by flow cytometric analysis.

RESULTS

Downregulation of miR-144 and upregulation of TFAP4 were shown in HSCR. Luciferase reporter assay indicated that miR-144 reduced luciferase activity in 293T and SH-SY5Y transfected with TFAP4-WT-3UTR luciferase reporter and confirmed TFAP4 was the downstream target gene of miR-144. Data showed that miR-144 promoted the cell proliferation, migration and invasion of 293T and SH-SY5Y, while TFAP4 blocked the cell proliferation, migration and invasion. TFAP4 overexpression reversed the miR-144-mediated cell proliferation, migration and invasion of 293T and SH-SY5Y.

CONCLUSIONS

Downregulation of miR-144 blocked the cell proliferation and migration of nerve cells via targeting TFAP4 and contributed to the pathogenesis of HSCR. This provides an innovative and candidate target for treatment of HSCR.

VE-822 upregulates the deubiquitinase OTUD1 to stabilize FHL1 to inhibit the progression of lung adenocarcinoma

BACKGROUND

The deubiquitinase ovarian tumor domain-containing 1 (OTUD1) has been considered as a tumor suppressor in many tumors, but there is minimal research on the role of OTUD1 in lung adenocarcinoma (LUAD) pathogenesis.

METHODS

Bioinformatics analyses and western blot were applied for investigating OTUD1 expression in lung cancer and the drug that upregulated OTUD1. Kaplan-Meier analysis with log-rank test was used for survival analyses. IP-MS and co-IP were performed for identifying potential protein interactions with OTUD1. In vitro and in vivo assays were used for exploring the function of OTUD1 during the progression of LUAD.

RESULTS

OTUD1 was dramatically downregulated in tumors and cell lines of human lung cancer. OTUD1 inhibited proliferation and migration of lung cancer cells in vitro. Moreover, OTUD1 inhibited growth of xenografts in nude mice and formation of primary lung tumors in urethane-induced lung cancer model. Mechanistically, we showed that OTUD1 deubiquitinated and stabilized FHL1. Furthermore, we listed and identified VE-822 as a candidate agonist for OTUD1. VE-822 inhibited proliferation of lung adenocarcinoma both in vitro and in vivo.

CONCLUSION

These results indicated that the deubiquitinase OTUD1, which was upregulated by VE-822, inhibited the progression of LUAD in vitro and in vivo by deubiquitinating and stabilizing FHL1.

FHL1 as a novel prognostic biomarker and correlation with immune infiltration levels in lung adenocarcinoma

Aim: We aimed to examine the effect of FHL1 in the diagnosis and prognosis of non-small-cell lung cancer and its relationship with tumor-infiltrating immune cells. Methods: FHL1 expression status and influence on clinical characteristics, diagnosis and prognosis in non-small-cell lung cancer were assessed. Interaction networks of FHL1 were revealed, and a correlation analysis between FHL1 expression and tumor immunity was performed. Results: FHL1 expression was significantly lower in tumors, and downregulated FHL1 predicted a worse prognosis for lung adenocarcinoma. FHL1 expression was correlated with tumor-infiltrating immune cells, immune checkpoints and chemokine levels. Conclusion: FHL1 is a powerful biomarker to evaluate the diagnosis and prognosis and immune infiltration level of lung adenocarcinoma.

First Report of FARSA in the Regulation of Cell Cycle and Survival in Mantle Cell Lymphoma Cells via PI3K-AKT and FOXO1-RAG1 Axes

Cancer-associated factors have been largely identified in the understanding of tumorigenesis and progression. However, aminoacyl-transfer RNA (tRNA) synthetases (aaRSs) have so far been neglected in cancer research due to their canonical activities in protein translation and synthesis. FARSA, the alpha subunit of the phenylalanyl-tRNA synthetase is elevated across many cancer types, but its function in mantle cell lymphoma (MCL) remains undetermined. Herein, we found the lowest levels of FARSA in patients with MCL compared with other subtypes of lymphomas, and the same lower levels of FARSA were observed in chemoresistant MCL cell lines. Unexpectedly, despite the essential catalytic roles of FARSA, knockdown of FARSA in MCL cells did not lead to cell death but resulted in accelerated cell proliferation and cell cycle, whereas overexpression of FARSA induced remarkable cell-cycle arrest and overwhelming apoptosis. Further RNA sequencing (RNA-seq) analysis and validation experiments confirmed a strong connection between FARSA and cell cycle in MCL cells. Importantly, FARSA leads to the alteration of cell cycle and survival via both PI3K-AKT and FOXO1-RAG1 axes, highlighting a FARSA-mediated regulatory network in MCL cells. Our findings, for the first time, reveal the noncanonical roles of FARSA in MCL cells, and provide novel insights into understanding the pathogenesis and progression of B-cell malignancies.

Identidication of novel biomarkers in non-small cell lung cancer using machine learning

Lung cancer is one of the leading causes of cancer-related deaths worldwide, and non-small cell lung cancer (NSCLC) accounts for a large proportion of lung cancer cases, with few diagnostic and therapeutic targets currently available for NSCLC. This study aimed to identify specific biomarkers for NSCLC. We obtained three gene-expression profiles from the Gene Expression Omnibus database (GSE18842, GSE21933, and GSE32863) and screened for differentially expressed genes (DEGs) between NSCLC and normal lung tissue. Enrichment analyses were performed using Gene Ontology, Disease Ontology, and the Kyoto Encyclopedia of Genes and Genomes. Machine learning methods were used to identify the optimal diagnostic biomarkers for NSCLC using least absolute shrinkage and selection operator logistic regression, and support vector machine recursive feature elimination. CIBERSORT was used to assess immune cell infiltration in NSCLC and the correlation between biomarkers and immune cells. Finally, using western blot, small interfering RNA, Cholecystokinin-8, and transwell assays, the biological functions of biomarkers with high predictive value were validated. A total of 371 DEGs (165 up-regulated genes and 206 down-regulated genes) were identified, and enrichment analysis revealed that these DEGs might be linked to the development and progression of NSCLC. ABCA8, ADAMTS8, ASPA, CEP55, FHL1, PYCR1, RAMP3, and TPX2 genes were identified as novel diagnostic biomarkers for NSCLC. Monocytes were the most visible activated immune cells in NSCLC. The knockdown of the TPX2 gene, a biomarker with a high predictive value, inhibited A549 cell proliferation and migration. This study identified eight potential diagnostic biomarkers for NSCLC. Further, the TPX2 gene may be a therapeutic target for NSCLC.

MiR-96-5p Facilitates Lung Adenocarcinoma Cell Phenotypes by Inhibiting FHL1

Objective

FHL1 is understood as a tumor repressor gene in various cancers and a possible target for cancer treatment. We investigated the influences of FHL1 on cell functions as well as its molecular mechanisms in lung adenocarcinoma (LUAD) cells.

Methods

The miRNA-mRNA modulatory axis was predicted by bioinformatics. The expression levels of FHL1 mRNA and protein in LUAD cells were, respectively, analyzed by qRT-PCR and western blot. Dual luciferase analysis was introduced to verify the interaction between miR-96-5p and FHL1. CCK-8, cell colony formation, and Transwell assays were utilized to analyze proliferation, colony formation, migration, and invasion of A549 cells.

Results

Expression of FHL1 mRNA and protein in LUAD tissue and cells was downregulated, which was linked with poor prognoses of patients. In addition, FHL1 overexpression could hamper colony formation, proliferation, invasion, and migration of LUAD cells. In addition, dual-luciferase analysis verified miR-96-5p as an upstream regulator of FHL1. Overexpression of miR-96-5p suppressed FHL1 expression in LUAD cells and promoted proliferation, invasion, and migration of LUAD cells, while overexpression of FHL1 could simultaneously restore the above-mentioned promoting effect.

Conclusion

MiR-96-5p fostered cell malignant behaviors by targeting FHL1. This research uncovered the regulatory mechanism of FHL1 in LUAD and offered optional therapeutic targets for LUAD patients.

Function of BCLAF1 in human disease

Originally identified as a regulator of apoptosis and transcription, B-cell lymphoma-2-associated transcription factor 1 (BCLAF1) has since been shown to be associated with a multitude of biological processes, such as DNA damage response, splicing and processing of pre-mRNA, T-cell activation, lung development, muscle cell proliferation and differentiation, autophagy, ischemia-reperfusion injury, and viral infection. In recent years, an increasing amount of evidence has shown that BCLAF1 acts as either a tumor promoter or tumor suppressor in tumorigenesis depending on the cellular context and the type of cancer. Even in the same tumor type, BCLAF1 may have opposite effects. In the present review, the subcellular localization, structural features, mutations within BCLAF1 will be described, then the regulation of BCLAF1 and its downstream targets will be analyzed. Furthermore, the different roles and possible mechanisms of BCLAF1 in tumorigenesis will also be highlighted and discussed. Finally, BCLAF1 may be considered as a potential target for cancer therapy in the future.

FHL1 Inhibits the Progression of Colorectal Cancer by Regulating the Wnt/β-Catenin Signaling Pathway

Purpose: This study aims to explore the FHL1 expression level in colorectal cancer (CRC) patients, analyze its association with patient survival and investigate the role of FHL1 in CRC. Methods: We used secondary sequencing to profile mRNA expression in CRC tissue and corresponding adjacent normal tissue from four CRC patients. We focus on FHL1 and analyzed the association between its expression level and clinical indicators. Furthermore, we explored the functional role of FHL1 in colorectal cancer tumorigenesis by transfecting cells with siRNA or overexpression plasmids. Results: Hierarchical clustering revealed significantly differentially expressed mRNAs. FHL1 expression was significantly lower in CRC tissue than in adjacent normal tissue as well as in CRC cell lines relative to NCM460. Low FHL1 expression in CRC tissue correlated with poor patient survival. Our data demonstrated that overexpression of FHL1 inhibited the proliferation, colony formation potential, and expression of CdK4 and Cyclin D1, whereas ablating FHL1 promoted their proliferation and colony formation potential, suggesting that FHL1 acts as a tumor suppressor in CRC. Moreover, we showed that FHL1 inhibited the proliferation of colorectal cancer cells by negatively regulating the Wnt/β-catenin signaling pathway. Conclusion: FHL1 is a potential tumor suppressor gene in colorectal cancer, and regulation of the FHL1-Wnt/β-catenin pathway may be part of its antitumor mechanism.

FHL3 Contributes to EMT and Chemotherapy Resistance Through Up-Regulation of Slug and Activation of TGFβ/Smad-Independent Pathways in Gastric Cancer

Background

Gastric cancer presents high risk of metastasis and chemotherapy resistance. Hence, it is important to understand the mechanisms of gastric cancer distant metastasis and chemotherapeutic resistance. Our previous study has revealed Four and a Half LIM Domains 3 (FHL3) plays as a binding partner of Glycogen Synthase Kinase 3 Beta (GSK3β), promoted tumor metastasis in pancreatic cancer. However, the role of FHL3 in gastric cancer still remains unclear.

Methods

TCGA database and clinical samples are used for exploring the role of FHL3 in disease progression and prognosis. Oxaliplatin (OHP) resistance cell lines were established to study the role of FHL3 in chemotherapy resistance. The experiments about cell proliferation, apoptosis, and metastasis were performed to measure the chemotherapy effects of sh-FHL3 on gastric cancer cell lines and in vivo. That FHL3 changed the EMT phenotype was verified by western blot. Finally, we explored the mechanism of FHL3-mediated EMT and chemotherapy resistance.

Results

mRNA and protein level of FHL3 were significantly up-regulated in gastric cancer tissues when compared with adjacent tissue. FHL3 higher expression is always accompanied with higher TNM stage and worse overall survival. FHL3 over-expressed could lead to OHP resistance. Knockdown of FHL3 slightly inhibited the cell growth, while it obviously sensitized the chemotherapy in vivo and in vitro. In addition, down-regulation of FHL3 increased the mesenchymal markers, such as Slug, Snail, Twist Family BHLH Transcription Factor 1 (Twist1), and Vimentin, while it decreased the epithelial marker E-cadherin. Cell and animal experiments also proved that down-regulation of FHL3 can decrease cancer cell metastasis. For mechanism study, FHL3 knockdown down-regulated the expression level of Mitogen-Activated Protein Kinase (MAPK)/Extracellular Regulated Protein Kinase (ERK) pathway and Transforming Growth Factor-β (TGFβ)/Phosphatidylinositol 3-Kinase (PI3K)/protein kinase B(Akt)/GSK3β-(Ring Finger Protein 146) RNF146/ubiquitin pathway. FHL3 competitively bonded the ubiquitin complex (Slug/GSK3β/RNF146) with Slug and inhibited ubiquitination of Slug. Mesenchymal phenotype cells hold higher level of Multidrug Resistance Gene1 (MDR1), and the FHL3 knockdown reverts the MDR1 in this type cell.

Conclusion

FHL3 high expression contributed to EMT and chemotherapy resistance via MAPK, and PI3K pathways were activated. FHL3 competitively bonded the ubiquitin complex with Slug, resulting in the up-regulation of Slug and leading to metastasis of gastric cancer.

Secretome of Activated Fibroblasts Induced by Exosomes for the Discovery of Biomarkers in Non-Small Cell Lung Cancer

Molecules involved in crosstalk between tumor cells and fibroblasts play vital roles in tumor progression. Extracellular matrix proteins, whose abundance is altered after being affected by tumor-derived exosomes, possess considerable promise as biomarkers for diagnosis or prognosis. In this study, quantitative proteomics is employed to determine the abundance of proteins secreted by normal fibroblasts and exosome-activated fibroblasts, which first identify differentially secreted proteins affected by lung cancer cell-derived exosomes. Based on the differentially secreted proteins and multiple independent datasets comprising 1897 patient samples with non-small cell lung carcinoma or other lung diseases, a diagnostic marker is identified that can effectively distinguish tumor tissues from normal tissue, as well as tumor-associated stroma from normal stroma, and a five-gene prognostic signature is presented with independent prognostic impact to identify patients who may require further adjuvant therapy after surgical resection. In addition, the secretome provides novel potential targets for clinical treatment.

MiR-96-5p Induced by Palmitic Acid Suppresses the Myogenic Differentiation of C2C12 Myoblasts by Targeting FHL1

Skeletal myogenesis is a multi-stage process that includes the cell cycle exit, myogenic transcriptional activation, and morphological changes to form multinucleated myofibers. Recent studies have shown that saturated fatty acids (SFA) and miRNAs play crucial roles in myogenesis and muscle homeostasis. Nevertheless, the target molecules and myogenic regulatory mechanisms of miRNAs are largely unknown, particularly when myogenesis is dysregulated by SFA deposition. This study investigated the critical role played by miR-96-5p on the myogenic differentiation in C2C12 myoblasts. Long-chain SFA palmitic acid (PA) significantly reduced FHL1 expression and inhibited the myogenic differentiation of C2C12 myoblasts but induced miR-96-5p expression. The knockdown of FHL1 by siRNA stimulated cell proliferation and inhibited myogenic differentiation of myoblasts. Interestingly, miR-96-5p suppressed FHL1 expression by directly targeting the 3’UTR of FHL1 mRNA. The transfection of an miR-96-5p mimic upregulated the expressions of cell cycle-related genes, such as PCNA, CCNB1, and CCND1, and increased myoblast proliferation. Moreover, the miR-96-5p mimic inhibited the expressions of myogenic factors, such as myoblast determination protein (MyoD), myogenin (MyoG), myocyte enhancer factor 2C (MEF2C), and myosin heavy chain (MyHC), and dramatically impeded differentiation and fusion of myoblasts. Overall, this study highlights the role of miR-96-5p in myogenesis via FHL1 suppression and suggests a novel regulatory mechanism for myogenesis mediated by miRNA in a background of obesity.

FHL1 promotes glioblastoma aggressiveness through regulating EGFR expression

The four-and-a-half LIM domain protein 1 (FHL1) plays a key role in multiple cancers. Here, we characterized its role in glioblastoma (GBM), the most common and incurable form of brain cancer. Overexpression of FHL1 promotes growth, migration, and invasion of GBM cells in vivo and in vitro. In contrast, FHL1 silencing by RNAi exhibits the opposite effects. FHL1 interacts with the transcription factor SP1 to upregulate epidermal growth factor receptor (EGFR) expression and activate the downstream signaling cascades, including Src, Akt, Erk1/2, and Stat3, leading to GBM malignancy. FHL1 is highly expressed and positively correlated with EGFR levels in human GBM, particularly those of the classical subtype. Our results suggest that the FHL1-SP1-EGFR axis plays a tumor-promoting role, and highlight the translational potential of inhibiting FHL1 for GBM treatment.

MiR-183-5p Promotes Proliferation, Metastasis and Angiogenesis in Breast Cancer Cells through Negatively Regulating Four and a Half LIM Protein 1

Purpose

Four and a half LIM protein 1 (FHL1) is involved in breast cancer (BC) development, but the regulatory mechanism involved remain unclear. In the present study, we examined the role of FHL1 in BC development.

Methods

The expression of FHL1, miR-183-5p, and miR-96-5p in BC tissues was analyzed using StarBase analysis. FHL1 expression in BC tissues, a normal human breast epithelial cell line, and BC cell lines was detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The relationship between FHL1 and miR-183-5p/miR-96-5p was analyzed via Pearson's rank correlation, TargetScan, and a dual-luciferase reporter assay. BT549 and MDA-MB-231 cells were transfected with either FHL1 and miR-183-5p mimics, or siFHL1 and a miR-183-5p inhibitor, respectively. The viability, colony number, migration, invasion, and tube length of BT549 and MDA-MB-231 cells were examined using cell counting kit-8, colony formation, wound-healing, Transwell, and tube formation assays, respectively. The levels of FHL1, vascular endothelial growth factor (VEGF), p53, E-cadherin, N-cadherin, and vimentin were quantified using western blotting and qRT-PCR.

Results

FHL1 expression was downregulated in BC tissues and cells, whereas miR-183-5p and miR-96-5p were upregulated in BC tissues (negative correlation with FHL1 expression). FHL1 overexpression inhibited the viability, colony number, migration, and invasion of BC cells and the expression of VEGF, N-cadherin, and vimentin, and increased the expression of FHL1, p53, and E-cadherin in BT549 cells. Furthermore, a miR-183-5p mimic reversed these effects of FHL1 overexpression, whereas FHL1 silencing caused opposite results to those observed in MDA-MB-231 cells; however, this was reversed by a miR-183-5p inhibitor.

Conclusion

Our study suggests that miR-183-5p promotes cell proliferation, metastasis, and angiogenesis by negatively regulating FHL1 in BC.

Four and a half LIM domains protein 1 can be as a double-edged sword in cancer progression

Four and a half LIM domains protein 1 (FHL1), as the name suggests, contains four and a half LIM domains capable of interacting with various molecules, including structural proteins, kinases, and transcriptional machinery. FHL1 contains a zinc-finger domain and performs diverse roles in regulation of gene transcription, cytoarchitecture, cell proliferation, and signal transduction. Several studies have validated the importance of FHL1 in muscle development, myopathy, and cardiovascular diseases. Mutations in the FHL1 gene are associated with various myopathies. Recently, FHL1 was identified as a major host factor for chikungunya virus (CHIKV) infection in both humans and mice. Based on more recent findings over the last decade, FHL1 is proposed to play a dual role in cancer progression. On the one hand, FHL1 expression is suppressed in several cancer types, which correlates with increased metastatic disease and decreased survival. Moreover, FHL1 is reported to inhibit tumor cell growth and migration by associating with diverse signals, such as TGF-β and ER, and therefore considered a tumor suppressor. On the other hand, FHL1 can function as an oncogenic protein that promotes tumor progression upon phosphorylation, reflecting complex roles in cancer. This review primarily focuses on the dual role and underlying mechanisms of action of FHL1 in human cancer progression and its clinical relevance.

Downregulation of FHL1 protein in glioma inhibits tumor growth through PI3K/AKT signaling

Human four-and-a-half LIM domains protein 1 (FHL1) is a member of the FHL protein family, which serves an important role in multiple cellular events by interacting with transcription factors using its cysteine-rich zinc finger motifs. A previous study indicated that FHL1 was downregulated in several types of human cancer and served a role as a tumor suppressive gene. The overexpression of FHL1 inhibited tumor cell proliferation. However, to the best of our knowledge, there is no evidence to confirm whether FHL1 affected glioma growth, and the molecular mechanisms through which FHL1 represses tumor development remain unclear. In the present study, the expression level of FHL1 was determined using immunohistochemical staining in 114 tumor specimens from patients with glioma. The results indicated that FHL1 expression was negatively associated with the pathological grade of gliomas. Furthermore, Kaplan-Meier survival curves demonstrated that the patients with an increased FHL1 expression exhibited a significantly longer survival time, suggesting that FHL1 may be a prognostic marker for glioma. The protein level of FHL1 was relatively increased in the U251 glioma cell line compared with that in the U87 cell line. Therefore, FHL1 was knocked down in U251 by siRNA and overexpressed in U87, and it was identified that FHL1 significantly decreased the activation of PI3K/AKT signaling by interacting with AKT. Further experiments verified that FHL1 inhibited the growth of gliomas in vivo by modulating PI3K/AKT signaling. In conclusion, the results of the present study demonstrated that FHL1 suppressed glioma development through PI3K/AKT signaling.

Genome-wide identification of FHL1 as a powerful prognostic candidate and potential therapeutic target in acute myeloid leukaemia

Background

Acute myeloid leukaemia (AML) is a malignant haematological tumour with high heterogeneity and mortality. A reliable prognostic assessment is critical for treatment strategies. However, the current prognostic evaluation system of AML is insufficient.

Methods

Genome-wide univariate Cox regression analysis was performed on three independent AML datasets to screen for the prognostic-related genes. Kaplan–Meier survival analysis was employed to verify the efficacy of FHL1 in evaluating overall survival in 1298 de novo AML patients, 648 non-acute promyelocytic leukaemia AML patients and 407 cytogenetically normal AML patients; the data for some of these patients were also used for EFS and RFS validation. Multivariate Cox regression was performed to validate FHL1 as an independent prognostic indicator. WGCNA, GSEA, and gene correlation analysis were applied to explore the mechanism of FHL1 in AML. The synergistic cytocidal effect of FHL1 knockdown was verified in in vitro experiments.

Findings

Comprehensive genome-wide analyses and large-sample validation showed that FHL1 is a powerful prognostic candidate for overall survival, event-free survival, and relapse-free survival in AML and is independent of prognosis-related clinical factors and genetic abnormalities. The molecular mechanism may occur through regulation of FHL1 in leukaemia stem cells, tumour-associated signalling pathways, and transmembrane transport of chemotherapeutic drugs. FHL1-targeted intervention enhances the sensitivity of AML cells to cytarabine.

Interpretation

FHL1 may serve as an evaluation factor for clinical strategy selection, and its targeted intervention may be beneficial for chemotherapy in AML patients.

FHL3 promotes pancreatic cancer invasion and metastasis through preventing the ubiquitination degradation of EMT associated transcription factors

Pancreatic ductal adenocarcinoma (PDAC) is intractable due to its strong invasiveness and metastatic ability. Epithelial-mesenchymal transition (EMT) is the pivotal driver of tumor invasion and metastasis. The four-and-a-half LIM domain (FHL) family is involved in regulating transforming growth factor (TGF)-β and Ras signaling, which might control the EMT process. In this study, we found that higher expression of four-and-a-half LIM domains 3 (FHL3) predicted poor prognosis in PDAC. The decreasing of FHL3 changed the EMT phenotype by blocking the TGFβ/Atk/GSK3β/ubiquitin pathways. Interestingly, the GSK3β inhibitor could abrogate the role of FHL3 in the regulation of snail1 and twist1 expression, which implied that GSK3β plays a pivotal role in the FHL3-mediated EMT process. Furthermore, we found that FHL3 can directly bind to GSK3β, which weakened the interaction between GSK3β and snail1/twist1. We also found that the LIM-3 domain of FHL3 was required for the binding of FHL3 to GSK3β. Collectively, our study implied that FHL3, as a binding partner of GSK3β, promoted tumor metastasis in PDAC through inhibiting the ubiquitin-degradation of snail1 and twist1.

Long Intergenic Noncoding RNA 00261 Acts as a Tumor Suppressor in Non-Small Cell Lung Cancer via Regulating miR-105/FHL1 Axis

Purpose: Long noncoding RNAs (lncRNAs) have recently received more attention for their roles in tumor progression. LINC00261 was studied in this research to identify how it affects the progression of non-small cell lung cancer (NSCLC).

Methods: Firstly, the expression of LINC00261 in NSCLC cells and paired samples of NSCLC tissue was detected by RT-qPCR. Then, the associations between LINC00261 expression level and clinicopathological characteristics were evaluated. Furthermore, functional assays of cell proliferation, colony formation and transwell, as well as western blot assay, luciferase assay and RNA immunoprecipitation (RIP) assay were conducted. Afterwards, the effects of LINC00261 expression on NSCLC formation and growing were confirmed by in vivo models.

Results: As results, expression of LINC00261 was significantly down-regulated in tumor samples than that in normal samples, which was correlated with the lymphatic metastasis, tumor size, tumor stage as well as patient survival time. Knockdown of LINC00261 inhibited tumor growth and invasion ability in vitro. In addition, miR-105 was identified as a direct target of LINC00261 via mechanism experiments and its expression in tumor tissues negatively correlated to LINC00261 expression. Further experiments found that Four and expression of Half LIM domains 1 (FHL1) was negatively correlated with miR-105 but positively with LINC00261. Moreover, in vivo assays verified the overexpression of LINC00261 could suppress formation of NSCLC and regulate the expression of miR-105/FHL1 axis.

Conclusions: These results indicate that LINC00261 could suppress metastasis and proliferation of NSCLC via suppressing miR-105/FHL1 axis, which may offer a new vision for interpreting the mechanism of NSCLC development.

MicroRNA-6077 enhances the sensitivity of patients-derived lung adenocarcinoma cells to anlotinib by repressing the activation of glucose transporter 1 pathway

Anlotinib is a novel molecular targeted agent targeting the vascular endothelial growth factor receptor, which differs from the other currently available non-small cell lung cancer (NSCLC) molecular targeted drugs targeting this receptor. Although the application of anlotinib may bring new hope for patients with advanced NSCLC, the cost of treatment is high. The results of this study showed that microRNA-6077 (miR-6077) represses the expression of GLUT1 (glucose transporter 1) and enhances the sensitivity of patient-derived lung adenocarcinoma (AC) cells to anlotinib. The miR-6077, which potentially binds to the 3'untranslated region of GLUT1, was identified and screened by miRDB, an online tool; sequences of miR-6077 were prepared as lentivirus particles. A549 cells (a lung adenocarcinoma cell line) and five patient-derived AC cell lines were infected with control miRNA or miR-6077, and subsequently treated with the indicated concentration of anlotinib. The expression of proteins, such as GLUT1, was determined by western blotting. The antitumor effect of anlotinib was identified through in-vitro (e.g., MTT) or in-vivo methods (e.g., subcutaneous tumor model). Overexpression of miR-6077 repressed the expression of GLUT1 and decreased the glucose uptake, lactate production, or ATP generation in AC cells. In addition, MiR-6077 may enhance the antitumor effect of anlotinib on A549 or patient-derived AC cell lines. Therefore, our results indicated that miR-6077 represses the expression of GLUT1 and enhances the sensitivity of patients-derived lung AC cells to anlotinib.

Overexpression Of hsa-miR-664a-3p Is Associated With Cigarette Smoke-Induced Chronic Obstructive Pulmonary Disease Via Targeting FHL1

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is recognized as a chronic lung disease with incomplete reversible airflow limitation, but its pathophysiology was still not clear. This study aimed at investigating regulatory roles of special miRNA-mRNA axis in COPD development.

METHODS

Differentially expressed miRNAs and downstream mRNAs were screened from the Gene Expression Omnibus (GEO) dataset by using the LIMMA package in R software. Weighted Gene Co-expression Network Analysis (WGCNA) was used to construct a co-expression network for COPD. The correlation of dysregulated miRNA(s) and COPD was analyzed, and miRNAs with significant differences were validated in peripheral blood mononuclear cells (PBMCs) from COPD patients by real-time PCR. Regulatory roles of candidate miRNAs and targeted mRNAs were investigated in vitro study.

RESULTS

Thirteen modules of co-expressed miRNAs and mRNAs were constructed from a selected cohort with WGCNA. Turquoise module with 12 differentially expressed miRNAs and 120 mRNAs was significantly correlated with COPD. The expression of hsa-miR-664a-3p, an upregulated miRNA in the module, was increased both in lung tissue and PBMCs from COPD patients, whereas that targeted four and a half LIM domains 1 (FHL1) gene was decreased and positively correlated with forced expiratory volume in 1 sec (FEV1)/forced vital capacity (FVC%) (r = 0.59, p < 0.01). In vitro, luciferase activity assay revealed FHL1 as a target of hsa-miR-664a-3p and it could be directly downregulated by overexpression of hsa-miR-664a-3p. Furthermore, cigarette smoke extract could increase hsa-miR-664a-3p level and decrease FHL1 level in Beas-2B cells.

CONCLUSION

The present study validated significant upregulation of hsa-miR-664a-3p in COPD patients, and its target gene FHL1 was downregulated and positively correlated with FEV1/FVC%; both hsa-miR-664a-3p and FHL1 could be regulated by cigarette smoke extract. Results of bioinformatic analyses and expanded validation suggest that the axis from hsa-miR-664a-3p to FHL1 might play a key role in cigarette smoke-induced COPD, and the exact mechanism should be confirmed in further studies.

Human lung epithelial cells cultured in the presence of radon-emitting rock experience gene expression changes similar to those associated with tobacco smoke exposure

Radon is the second leading cause of lung cancer, after tobacco smoke. While tobacco smoke-induced carcinogenesis has been studied extensively, far less is known about radon-induced carcinogenesis, particularly in relation to the influence of radon on gene expression. The objectives of the work described herein were to (a) determine if and how exposure to low dose radon-emitting rock influences cells, at the gene expression level, and (b) compare any gene expression changes resulting from the exposure to radon-emitting rock with those induced by exposure to tobacco smoke. Any potential radiation-induced gene expression changes were also compared to those induced by exposure to cannabis smoke, a non-carcinogen at low doses, used here as a smoke exposure comparator. Human lung epithelial cells were exposed to radon-emitting rock, tobacco smoke or cannabis smoke, over months, and RNA-sequencing was carried out. We found that the rock-exposed cells experienced significant gene expression changes, particularly of the gene AKR1C3, and that these changes, over time, increasingly reflected those associated with exposure to tobacco, but not cannabis, smoke. We postulate that the early gene expression changes common to both the radiation and tobacco smoke exposures constitute a related - potentially pre-carcinogenic - response. Our findings suggest that the length of time a dividing population of cells is exposed to a constant low concentration of radon (with a potential cumulative absorbed dose) could be an important risk parameter for neoplastic transformation/carcinogenesis.

Proteomic analysis of human prostate cancer PC-3M-1E8 cells and PC-3M-2B4 cells of same origin but with different metastatic potential

Prostate cancer (PCa) is the second most frequently diagnosed cancer and the fifth leading cause of death from cancer in men worldwide. Increased understanding of the prostate cancer metastasis mechanisms will help identify more efficient intervention strategies to prevent or treat this deadly disease in the future. To identify the candidate proteins that contribute to metastasis of PCa, isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis was performed to explore differentially expressed proteins between two homologous human prostate cancer cell lines including highly-metastatic PC-3M-1E8 cell line and poorly-metastatic PC-3M-2B4 cell line. Here, a total of 58 proteins were identified to be significantly differentially expressed between PC-3M-1E8 and PC-3M-2B4 cells, which were further verified using real-time quantitative PCR and western blot analysis. The bioinformatic analysis suggested that the differentially expressed proteins, like MMP1 and FHL1, may contribute to the higher metastatic ability of PC-3M-1E8 cells than PC-3M-2B4 cells. In addition, functional analyses proved MMP1’s positive effect on the higher metastatic ability of PC-3M-1E8 cells than PC-3M-2B4 cells. These findings provided a unique resource to specifically reveal the complex molecular regulatory mechanisms underlying the progression of prostate cancer from poorly-metastatic to highly-metastatic stage.

IGF2-derived miR-483-3p associated with Hirschsprung's disease by targeting FHL1

HSCR (Hirschsprung's disease) is a serious congenital defect, and the aetiology of it remains unclear. Many studies have highlighted the significant roles of intronic miRNAs and their host genes in various disease, few was mentioned in HSCR although. In this study, miR-483-3p along with its host gene IGF2 (Insulin-like growth factor 2) was found down-regulated in 60 HSCR aganglionic colon tissues compared with 60 normal controls. FHL1 (Four and a half LIM domains 1) was determined as a target gene of miR-483-3p via dual-luciferase reporter assay, and its expression was at a higher level in HSCR tissues. Here, we study cell migration and proliferation in human 293T and SH-SY5Y cell lines by performing Transwell and CCK8 assays. In conclusion, the knockdown of miR-483-3p and IGF2 both suppressed cell migration and proliferation, while the loss of FHL1 leads to opposite outcome. Furthermore, miR-483-3p mimics could rescue the negative effects on cell proliferation and migration caused by silencing IGF2, while the FHL1 siRNA may inverse the function of miR-483-3p inhibitor. This study revealed that miR-483-3p derived from IGF2 was associated with Hirschsprung's disease by targeting FHL1 and may provide a new pathway to understand the aetiology of HSCR.

Src-mediated phosphorylation converts FHL1 from tumor suppressor to tumor promoter

FHL1 has been recognized for a long time as a tumor suppressor protein that associates with both the actin cytoskeleton and the transcriptional machinery. We present in this study a paradigm that phosphorylated FHL1 functions as an oncogenic protein by promoting tumor cell proliferation. The cytosolic tyrosine kinase Src interacts with and phosphorylates FHL1 at Y149 and Y272, which switches FHL1 from a tumor suppressor to a cell growth accelerator. Phosphorylated FHL1 translocates into the nucleus, where it binds to the transcription factor BCLAF1 and promotes tumor cell growth. Importantly, the phosphorylation of FHL1 is increased in tissues from lung adenocarcinoma patients despite the down-regulation of total FHL1 expression. Kindlin-2 was found to interact with FHL1 and recruit FHL1 to focal adhesions. Kindlin-2 competes with Src for binding to FHL1 and suppresses Src-mediated FHL1 phosphorylation. Collectively, we demonstrate that FHL1 can either suppress or promote tumor cell growth depending on the status of the sites for phosphorylation by Src.

Epigenetic analysis of FHL1 tumor suppressor gene in human liver cancer

Liver cancer is one of the most common types of cancer among human malignancies. Four and a half LIM domains 1 (FHL1), as a tumor suppressor gene, is frequently downregulated in multiple types of human cancer. However, the role and specific mechanisms of FHL1 as a tumor suppressor in liver cancer are poorly understood. The present study aimed to investigate the role and associated mechanisms of FHL1 in human liver cancer. The level of FHL1 mRNA in hepatocellular carcinoma (HCC) tissue specimens and cell lines derived from the human liver was determined using reverse transcription polymerase chain reaction and western blot analysis. The association between FHL1 expression and clinicopathological characteristics of patients with liver cancer was analyzed. Western blotting, small interfering RNA (siRNA) and chromatin immunoprecipitation were used to study the expression association of FHL1 and enhancer of zeste homolog 2 (EZH2) in human liver cancer and to explore the regulatory mechanism of FHL1 downregulation. Colony formation and migration assays were performed while FHL1 was overexpressed in Hep3B cells. The results showed that the expression of FHL1 mRNA in tumor tissue decreased, exhibiting a significant difference compared with the adjacent non-cancerous tissue (P<0.05). However, the downregulation of FHL1 was not significantly associated with the sex, age, hepatitis B virus infection status, tumor size, distant metastasis status or level of tumor differentiation of the patients. FHL1 was synergistically silenced by DNA methylation and histone modification, and 3-deanzaneplanocin A (DZNep), an inhibitor of EZH2, which is a histone methyltransferase of the polycomb repressive complex 2, which catalyzes histone H3 lysine 27 tri-methylation (H3K27me3). A significant association between FHL1 and EZH2 expression was identified in the female hepatocellular carcinoma (HCC) samples, but was not in the male HCC samples. FHL1 overexpression and DZNep treatment significantly suppressed the growth and migration of Hep3B cells by restoring FHL1 expression. H3K27me3 was significantly enriched at the FHL1 promoter region, as indicated by a chromatin immunoprecipitation assay, and associated with the epigenetic repression of the FHL1 tumor suppressor gene in HCC cell lines. In conclusion, the present study provides an insight into DNA methylation and EZH2-H3K27me3 epigenetic repression of FHL1 in human liver cancer.

Small leucine-rich proteoglycans (SLRPs) in the endometrium of polycystic ovary syndrome women: a pilot study

Background

Small leucine-rich proteoglycans (SLRPs) play an important role in tissue homeostasis and cell proliferation since these proteoglycans sequester multiple growth factors. However, the content of SLRPs in the endometrium of polycystic ovary syndrome (PCOS) women is unknown. Our purpose was to test the hypothesis that excessive endometrial proliferation in PCOS may be partly related to abnormalities in SLRPs.

Methods

In a cross section study a total of 20 endometrial samples were collected from 10 patients with PCOS and 10 ovulatory women during their proliferative (pre-ovulatory) phase. The study subjects were matched for age, body mass index and race. The age range was 20 to 35 years. All volunteers were evaluated in reproductive endocrinology clinic, Gynecology Division, Clinics Hospital, University of São Paulo Medical School Profile and concentration of small leucine-rich proteoglycans (decorin, lumican, fibromodulin and biglycan) were determined by immunohistochemical testing and Western blotting.

Results

Decorin and lumican demonstrated higher immunoreactivity and relative expression in the endometrium of women with PCOS compared to that of women with regular menstrual cycles.

Conclusion

Our data suggests that the endometrium of PCOS women demonstrate a greater content of SLRP than controls; decorin and lumican, in particular, were found in higher concentrations in the endometrium of PCOS women during the proliferative phase. These differences may, in part, explain the excess of endometrial proliferation frequently observed in PCOS. Further studies are warranted.

MEIS1 inhibits clear cell renal cell carcinoma cells proliferation and in vitro invasion or migration

BACKGROUND

Myeloid ecotropic viral integration site 1 (MEIS1) protein plays a synergistic causative role in acute myeloid leukemia (AML). However, MEIS1 has also shown to be a potential tumor suppressor in some other cancers, such as non-small-cell lung cancer (NSCLC) and prostate cancer. Although multiple roles of MEIS1 in cancer development and progression have been identified, there is an urgent demand to discover more functions of this molecule for further therapeutic design.

METHODS

MEIS1 was overexpressed via adenovirus vector in clear cell renal cell carcinoma (ccRCC) cells. Western blot and real-time qPCR (quantitative Polymerase Chain Reaction) was performed to examine the protein and mRNA levels of MEIS1. Cell proliferation, survival, in vitro migration and invasion were tested by MTT, colony formation, soft-agar, transwell (in vitro invasion/migration) assays, and tumor in vivo growthwas measured on nude mice model. In addition, flow-cytometry analysis was used to detect cell cycle arrest or non-apoptotic cell death of ccRCC cells induced by MEIS1.

RESULTS

MEIS1 exhibits a decreased expression in ccRCC cell lines than that in non-tumor cell lines. MEIS1 overexpression inhibits ccRCC cells proliferation and induces G1/S arrest concomitant with marked reduction of G1/S transition regulators, Cyclin D1 and Cyclin A. Moreover, MEIS1-1 overexpression also induces non-apoptotic cell death of ccRCC cells via decreasing the levels of pro-survival regulators Survivin and BCL-2. Transwell migration assay (TMA) shows that MEIS1 attenuates in vitro invasion and migration of ccRCC cells with down-regulated epithelial-mesenchymal transition (EMT) process. Further, in nude mice model, MEIS1 inhibits the in vivo growth of Caki-1 cells.

CONCLUSIONS

By investigating the role of MEIS1 in ccRCC cells' survival, proliferation, anchorage-independent growth, cell cycle progress, apoptosis and metastasis, in the present work, we propose that MEIS1 may play an important role in clear cell renal cell carcinoma (ccRCC) development.

A signature motif in LIM proteins mediates binding to checkpoint proteins and increases tumour radiosensitivity

Tumour radiotherapy resistance involves the cell cycle pathway. CDC25 phosphatases are key cell cycle regulators. However, how CDC25 activity is precisely controlled remains largely unknown. Here, we show that LIM domain-containing proteins, such as FHL1, increase inhibitory CDC25 phosphorylation by forming a complex with CHK2 and CDC25, and sequester CDC25 in the cytoplasm by forming another complex with 14-3-3 and CDC25, resulting in increased radioresistance in cancer cells. FHL1 expression, induced by ionizing irradiation in a SP1- and MLL1-dependent manner, positively correlates with radioresistance in cancer patients. We identify a cell-penetrating 11 amino-acid motif within LIM domains (eLIM) that is sufficient for binding CHK2 and CDC25, reducing the CHK2–CDC25 and CDC25–14-3-3 interaction and enhancing CDC25 activity and cancer radiosensitivity accompanied by mitotic catastrophe and apoptosis. Our results provide novel insight into molecular mechanisms underlying CDC25 activity regulation. LIM protein inhibition or use of eLIM may be new strategies for improving tumour radiosensitivity.

CDC25 phosphatases are important cell cycle regulators. Here, the authors show that the LIM domain-containing proteins (for example, FHL1) induce inhibitory CDC25 phosphorylation resulting in radioresistance and that a specific peptide can increase tumour radiosensitivity by increasing CDC25 activity.

MicroRNA-137 represses FBI-1 to inhibit proliferation and in vitro invasion and migration of hepatocellular carcinoma cells

The pro-oncogene factor that binds to inducer of short transcripts-1 (FBI-1), which is encoded by ZBTB7A gene and belongs to POK (POZ/BTB and KrÜppel) protein family, has been shown to enhance hepatocellular carcinoma (HCC) cells proliferation and multi-drug resistance (MDR) process. However, the possibility that FBI-1 is a therapeutic target for further HCC treatment remains poorly determined. In the current study, two microRNA (miRNA) target prediction programs (TargetScan and MiRanda) were used to identify miR-137 as a potential regulator of FBI-1. Our results showed that expression of miR-137 was downregulated, while FBI-1 was upregulated in clinical HCC specimens, compared with paired non-tumor specimens. Overexpression of miR-137 via adenoviral vector inhibited the proliferation and anchorage-independent growth of HCC cells, HepG2 and MHCC-97H. Our data also showed that miR-137 repressed endogenous expression level of FBI-1, as well as Notch-1 and Survivin. MiR-137 also inhibited in vitro invasion and migration of HCC cells and attenuated their epithelial-mesenchymal transition (EMT) process. Moreover, miR-137 suppressed the growth rate of HepG2 cells in nude mice model. Overexpression of miR-137 via its adenoviral vector enhanced the sensitivity of HepG2 cells to anti-tumor drugs and attenuated the MDR process of a resistance cell line HepG2/adriamycin (ADR). Thus, FBI-1 downregulation mediated by miR-137 overexpression may be a potential strategy for HCC treatment.

Whole-transcriptome analysis of mouse adipose tissue in response to short-term caloric restriction

Caloric restriction (CR) has been shown to extend the lifespan of many species by improving cellular function and organismal health. Additionally, fat reduction by CR may play an important role in lengthening lifespan and preventing severe age-related diseases. Interestingly, CR induced the greatest transcriptome change in the epididymal fat of mice in our study. In this transcriptome analysis, we identified and categorized 446 genes that correlated with CR level. We observed down-regulation of several signaling pathways, including insulin/insulin-like growth factor 1 (insulin/IGF-1), epidermal growth factor (EGF), transforming growth factor beta (TGF-β), and canonical wingless-type mouse mammary tumor virus integration site (Wnt). Many genes related to structural features, including extracellular matrix structure, cell adhesion, and the cytoskeleton, were down-regulated, with a strong correlation to the degree of CR. Furthermore, genes related to the cell cycle and adipogenesis were down-regulated. These biological processes are well-identified targets of insulin/IGF-1, EGF, TGF-β, and Wnt signaling. In contrast, genes involved in specific metabolic processes, including the tricarboxylic acid cycle and the electron transport chain were up-regulated. We performed in silico analysis of the promoter sequences of CR-responsive genes and identified two associated transcription factors, Paired-like homeodomain 2 (Pitx2) and Paired box gene 6 (Pax6). Our results suggest that strict regulation of signaling pathways is critical for creating the optimal energy homeostasis to extend lifespan.

X-linked FHL1 as a novel therapeutic target for head and neck squamous cell carcinoma

To identify X-linked novel tumor suppressors could provide novel insights to improve prognostic prediction and therapeutic strategy for some cancers. Using bioinformatics and Venn analysis of gene transcriptional profiling, we identified downregulation of X-linked four-and-a-half LIM domains protein 1 (FHL1) gene in head and neck squamous cell carcinoma (HNSCC). FHL1 functions were investigated and confirmed in vitro and in vivo. FHL1 downregulated mechanisms were analyzed in HNSCCs by using methylation specific PCR, bisulfate-based sequencing, 5-Aza-dC treatment and chromatin immunoprecipitation assays. Two independent HNSCC cohorts (the training cohort n = 105 and the validation cohort n = 101) were enrolled to evaluate clinical implications of FHL1 expression by using real-time PCR or immunohistochemistry. FHL1 mRNA and protein expressions were frequently decreased in HNSCCs. FHL1 overexpression or depletion gave rise to suppress or promote cell growth through Cyclin D1, Cyclin E and p27 dysregulations. Abundant occupy of EZH2 or H3K27Me3 was observed in FHL1 promoter except for DNA hypermethylation. Reduced FHL1 mRNA expression was notably associated with poor differentiation (p = 0.020). Multivariate analysis demonstrated FHL1 mRNA expression was identified as independent prognostic predictors of overall survival (OS) (p = 0.036; HR 0.520; Cl, 0.283-0.958) and disease-free survival (DFS) (p = 0.041; HR 0.527; Cl, 0.284-0.975), which was validated by another independent cohort (p = 0.021; HR 0.404; Cl, 0.187-0.871 for OS; p = 0.011; HR 0.407; Cl, 0.203-0.815 for DFS). These results suggest epigenetic silencing of X-linked FHL1 may have an important role in adjuvant therapeutic intervention of HNSCCs and is an independent prognostic factor in patients with HNSCCs.

miR-122 inhibits metastasis and epithelial-mesenchymal transition of non-small-cell lung cancer cells

miR-122 may function as a novel tumor suppressor. Expression of miR-122 could suppress the proliferation of multi-kinds of human cancer cell lines. In this work, expression of miR-122 via adenoviral vector in non-small-cell lung cancer (NSCLC) cells reduces the number of invasion and migration cells. miR-122 attenuates the epithelial-mesenchymal transition process, which mediates cancer cells metastasis in NSCLC cells A549 and H460. The mechanisms data reveals that miR-122 would disrupt the epithelial-mesenchymal transition process by downregulating PI3K/AKT activation via reducing endogenous expression of insulin-like growth factor 1 receptor. These data highlight the detailed roles and potential application of miR-122 in NSCLC cells.

MiR-122 Induces Radiosensitization in Non-Small Cell Lung Cancer Cell Line

MiR-122 is a novel tumor suppresser and its expression induces cell cycle arrest, or apoptosis, and inhibits cell proliferation in multiple cancer cells, including non-small cell lung cancer (NSCLC) cells. Radioresistance of cancer cell leads to the major drawback of radiotherapy for NSCLC and the induction of radiosensitization could be a useful strategy to fix this problem. The present work investigates the function of miR-122 in inducing radiosensitization in A549 cell, a type of NSCLC cells. MiR-122 induces the radiosensitization of A549 cells. MiR-122 also boosts the inhibitory activity of ionizing radiation (IR) on cancer cell anchor-independent growth and invasion. Moreover, miR-122 reduced the expression of its targeted genes related to tumor-survival or cellular stress response. These results indicate that miR-122 would be a novel strategy for NSCLC radiation-therapy.

STIP overexpression confers oncogenic potential to human non-small cell lung cancer cells by regulating cell cycle and apoptosis

Sip1/tuftelin‐interacting protein (STIP), a multidomain nuclear protein, is a novel factor associated with the spliceosome, yet its role and molecular function in cancer remain unknown. In this study, we show, for the first time, that STIP is overexpressed in non‐small cell lung cancer (NSCLC) tissues compared to adjacent normal lung tissues. The depletion of endogenous STIP inhibited NSCLC cell proliferation in vitro and in vivo, caused cell cycle arrest and induced apoptosis. Cell cycle arrest at the G2/M phase was associated with the expression and activity of the cyclin B1‐CDK1 (cyclin‐dependent kinase 1) complex. We also provide evidence that STIP knockdown induced apoptosis by activating both caspase‐9 and caspase‐3 and by altering the Bcl‐2/Bax expression ratio. RNA sequencing data indicated that the MAPK mitogen‐activated protein kinases, Wnt, PI3K/AKT, and NF‐κB (nuclear factor kappa‐light‐chain‐enhancer of activated B cells) signalling pathways might be involved in STIP‐mediated tumour regulation. Collectively, these results suggest that STIP may be a novel potential diagnostic and therapeutic target for NSCLC.

Long non-coding RNA: A new paradigm for lung cancer

Lung cancer is the leading cause of cancer-related deaths worldwide. Recent advances in whole genome transcriptome analysis have enabled the identification of numerous members of a novel class of non-coding RNAs, i.e., long non-coding RNAs (lncRNAs), which play important roles in a wide range of biological processes and whose deregulation causes human disease, including cancer. Herein we provide a comprehensive survey of lncRNAs associated with lung cancer, with particular focus on the functions that either facilitate or inhibit the progression of lung cancer and the pathways involved. Emerging data on the use of lncRNAs as biomarkers for the diagnosis and prognosis of cancer are also discussed. We cast this information within the wider perspective of lncRNA biogenesis and molecular functions in the cell. Relationships that exist between lncRNAs, genome-wide transcription, and lung cancer are discussed. Deepening our understanding on these processes is critical not only from a mechanistic standpoint, but also for the development of novel biomarkers and effective therapeutic targets for cancer patients.

FHL1 inhibits the growth of tongue squamous cell carcinoma cells via G1/S cell cycle arrest

Four and a half LIM protein 1 (FHL1) has been characterized as a tumor suppressor in various types of tumor. However, the biological function and underlying mechanism of FHL1 in tongue squamous cell carcinoma (TSCC) remain to be elucidated. The present study demonstrated that FHL1 inhibits anchorage‑dependent and ‑independent growth of TSCC cells in vitro and tumor growth in nude mice, as determined by cell proliferation and soft agar assays. Knockdown of FHL1 with FHL1 small interfering RNA (siRNA) promoted tumor growth in nude mice. Mechanistically, flow cytometric analysis showed that knockdown of FHL1 promoted G1/S cell cycle progression. Furthermore, expression of cell cycle‑associated regulators, cyclin D and cyclin E, were detected by western blotting and reverse transcription‑quantitative polymerase chain reaction. Cyclin D and cyclin E were markedly elevated at both the protein and mRNA level in the FHL1 siRNA‑transfected cells. These results suggested that FHL1 has a tumor suppressive role in TSCC and that FHL1 may be a useful target for TSCC gene therapy.

Identification of suitable genes contributes to lung adenocarcinoma clustering by multiple meta-analysis methods

BACKGROUND

With the widespread application of high-throughput technology, numerous meta-analysis methods have been proposed for differential expression profiling across multiple studies.

OBJECTIVES

We identified the suitable differentially expressed (DE) genes that contributed to lung adenocarcinoma (ADC) clustering based on seven popular multiple meta-analysis methods.

METHODS

Seven microarray expression profiles of ADC and normal controls were extracted from the ArrayExpress database. The Bioconductor was used to perform the data preliminary preprocessing. Then, DE genes across multiple studies were identified. Hierarchical clustering was applied to compare the classification performance for microarray data samples. The classification efficiency was compared based on accuracy, sensitivity and specificity.

RESULTS

Across seven datasets, 573 ADC cases and 222 normal controls were collected. After filtering out unexpressed and noninformative genes, 3688 genes were remained for further analysis. The classification efficiency analysis showed that DE genes identified by sum of ranks method separated ADC from normal controls with the best accuracy, sensitivity and specificity of 0.953, 0.969 and 0.932, respectively. The gene set with the highest classification accuracy mainly participated in the regulation of response to external stimulus (P = 7.97E-04), cyclic nucleotide-mediated signaling (P = 0.01), regulation of cell morphogenesis (P = 0.01) and regulation of cell proliferation (P = 0.01).

CONCLUSIONS

Evaluation of DE genes identified by different meta-analysis methods in classification efficiency provided a new perspective to the choice of the suitable method in a given application. Varying meta-analysis methods always present varying abilities, so synthetic consideration should be taken when providing meta-analysis methods for particular research.

DL-3-n-butylphthalide inhibits platelet activation via inhibition of cPLA2-mediated TXA2 synthesis and phosphodiesterase

Aberrant platelet activation plays a critical role in the pathogenesis of heart attack and stroke. DL-3-n-butylphthalide (NBP) has been approved in China to treat stroke with multiple mechanisms. The anti-stroke effects of NBP may be related to its antiplatelet effects reported in rats in addition to its antioxidative, antiapoptotic, and angiogenic effects. However, the effects and the underlying mechanisms of NBP on human platelets are not yet clear. In this study, we found that NBP concentration-dependently inhibited human platelet aggregation and ATP release induced by ADP, thrombin, U46619, arachidonic acid, or collagen. NBP also inhibited PAC-1 binding induced by ADP or thrombin and platelet spreading on immobilized fibrinogen. NBP reduced TXA2 synthesis induced by thrombin or collagen via inhibiting cPLA2 phosphorylation, concomitantly with a marked decrease in intracellular calcium mobilization. Moreover, NBP also inhibited human platelet phosphodiesterase (PDE) and elevated 3,5-cyclic adenosine monophosphate level in platelets. In conclusion, NBP significantly inhibits human platelet activation via inhibition of cPLA2-mediated TXA2 synthesis and PDE, and may be effective as an antiplatelet drug to treat other arterial thrombotic diseases.

MiR-410 is overexpressed in liver and colorectal tumors and enhances tumor cell growth by silencing FHL1 via a direct/indirect mechanism

FHL1 is an important tumor-suppressor that is downregulated in multiple tumors by unknown mechanisms. We demonstrated that miR-410 specifically targets the 3′UTR of FHL1. Furthermore, using DNA bisulfite modification and sequencing experiments, we demonstrated that the FHL1 promoter is hypermethylated in cancer cells. FHL1 methylation is increased upon miR-410 expression, suggesting that the regulation of FHL1 by miR-410 occurs by a dual mechanism. Using chromatin immunoprecipitation assays, we observed that miR-410 overexpression results in the increased binding of DNMT3A at the FHL1 promoter, which could explain how miR-410 regulates FHL1 methylation. Importantly, in vitro and in vivo results suggest that miR-410 may have oncogenic properties. Furthermore, both miR-410 and DNMT3A are upregulated in clinical human liver and colorectal tumors cancers. Our results suggest that miR-410 may function as an oncomiR and are consistent with its key function in regulating FHL1 in certain digestive system cancers.

SRC points the way to biomarkers and chemotherapeutic targets

The role of Src in tumorigenesis has been extensively studied since the work of Peyton Rous over a hundred years ago. Src is a non-receptor tyrosine kinase that plays key roles in signaling pathways controlling tumor cell growth and migration. Src regulates the activities of numerous molecules to induce cell transformation. However, transformed cells do not always migrate and realize their tumorigenic potential. They can be normalized by surrounding nontransformed cells by a process called contact normalization. Tumor cells need to override contact normalization to become malignant or metastatic. In this review, we discuss the role of Src in cell migration and contact normalization, with emphasis on Cas and Abl pathways. This paradigm illuminates several chemotherapeutic targets and may lead to the identification of new biomarkers and the development of effective anticancer treatments.

FHL1 on chromosome X is a single-hit gastrointestinal tumor-suppressor gene and contributes to the formation of an epigenetic field defect

Tumor-suppressor genes on chromosome X can be inactivated by a single hit, any of the point mutations, chromosomal loss and aberrant DNA methylation. As aberrant DNA methylation can be induced frequently, we here aimed to identify a tumor-suppressor gene on chromosome X inactivated by promoter DNA methylation. Of 69 genes on chromosome X upregulated by treatment of a gastric cancer cell line with a DNA-demethylating agent, 5-aza-2'-deoxycytidine, 11 genes had low or no expression in the cell line and abundant expression in normal gastric mucosae. Among them, FHL1 was frequently methylation-silenced in gastric and colon cancer cell lines, and methylated in primary gastric (21/80) and colon (5/50) cancers. Knockdown of the endogenous FHL1 in two cell lines by two kinds of shRNAs significantly increased cell growth in vitro and sizes of xenografts in nude mice. Expression of exogenous FHL1 in a non-expressing cell line significantly reduced its migration, invasion and growth. Notably, a somatic mutation (G642T; Lys214Asn) was identified in one of 144 colon cancer specimens, and the mutant FHL1 was shown to lack its inhibitory effects on migration, invasion and growth. FHL1 methylation was associated with Helicobacter pylori infection and accumulated in normal-appearing gastric mucosae of gastric cancer patients. These data showed that FHL1 is a methylation-silenced tumor-suppressor gene on chromosome X in gastrointestinal cancers, and that its silencing contributes to the formation of an epigenetic field for cancerization.

Euphol from Euphorbia tirucalli selectively inhibits human gastric cancer cell growth through the induction of ERK1/2-mediated apoptosis

Gastric cancer is one of the most common malignancies worldwide, and the main cause of cancer-related death in Asia. The present study assessed the anticancer effects of euphol, a triterpene alcohol with anti-inflammatory and antiviral activities on human gastric cancer cells. Euphol showed higher cytotoxicity activity against human gastric CS12 cancer cells than against noncancer CSN cells. In addition, it up-regulated the pro-apoptotic protein BAX and down-regulated the prosurvival protein Bcl-2, causing mitochondrial dysfunction, possibly by caspase-3 activation. The anti-proliferative effects of euphol were associated with the increased p27(kip1) levels and decreased cyclin B1 levels. Inhibition of ERK1/2 activation by PD98059 reversed euphol-induced pro-apoptotic protein expression and cell death. Taken together, these findings suggest that euphol selectively induced gastric cancer cells apoptosis by modulation of ERK signaling, and could thus be of value for cancer therapy.