LncNFYB promotes the proliferation of rheumatoid arthritis fibroblast-like synoviocytes via LncNFYB/ANXA2/ERK1/2 axis.

Long noncoding RNAs (lncRNAs) are specifically expressed in different diseases and regulate disease progression. To explore the functions of rheumatoid arthritis (RA)-specific lncRNA, we determined the lncRNA expression profile of fibroblast-like synoviocytes (FLS) obtained from patients with RA and osteoarthritis (OA) using a LncRNA microarray and identified up-regulated LncNFYB in RA as a potential therapeutic target. Using gain- and loss-of-function studies, LncNFYB was proven to promote FLS proliferation and cell cycle progress but not affect their invasion, migration, and apoptotic abilities. Further investigation discovered that LncRNA could combine with annexin A2 (ANXA2) and enhance the level of phospho-ANXA2 (Tyr24) in the plasma membrane area, which induced the activation of ERK1/2 to promote proliferation. These findings provide new insights into the biological functions of LncNFYB on modification of FLS, which may be exploited for the therapy of RA.

Health Care-Seeking Behaviors, Disease Progression, Medications, Knowledge of, and Attitudes Toward Systemic Lupus Erythematosus in China: Cross-sectional Survey Study.

BACKGROUND: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease involving multiple organs throughout the body. The health care-seeking behaviors, disease progression of SLE, and patients' knowledge of and attitudes toward SLE have not been characterized in China. OBJECTIVE: The aim of this study was to depict the health care-seeking behaviors, disease progression, and medications in patients with SLE and to examine the factors associated with their disease flares, knowledge, and attitudes toward SLE in China. METHODS: We conducted a cross-sectional survey in 27 provinces in China. Descriptive statistical methods were used to depict the demographic characteristics, health care-seeking behaviors, medications, and health status. Multivariable logistic regression models were used to identify the factors associated with disease flares, medication changes, and attitudes toward SLE. An ordinal regression model was used to examine the factors associated with the knowledge of the treatment guidelines. RESULTS: We recruited 1509 patients with SLE, and 715 had lupus nephritis (LN). Approximately 39.96% (603/1509) of the patients with SLE were primarily diagnosed with LN, and 12.4% (112/906) developed LN (mean time 5.2 years) from non-LN. Patients whose registered permanent residences or workplaces in other cities from the same province and adjacent provinces seeking health care accounted for 66.9% (569/850) and 48.8% (479/981) of the patients with SLE in the provincial capital cities, respectively. Mycophenolate mofetil was the most commonly used immunosuppressive drug in patients without LN (185/794, 23.3%) and patients with LN (307/715, 42.9%). Femoral head necrosis (71/228, 31.1%) and hypertension (99/229, 43.2%) were the most common adverse event (AE) and chronic disease during treatment, respectively. Change of hospitals for medical consultation (odds ratio [OR] 1.90, 95% CI 1.24-2.90) and development of 1 chronic disease (OR 3.60, 95% CI 2.04-6.24) and AE (OR 2.06, 95% CI 1.46-2.92) and more were associated with disease flares. A pregnancy plan (OR 1.58, 95% CI 1.18-2.13) was associated with changes in medication. Only 242 (16.03%) patients with SLE were familiar with the treatment guidelines, and patients with LN tended to be more familiar with the disease (OR 2.20, 95% CI 1.81-2.68). After receiving treatment, 891 (59.04%) patients changed their attitudes toward SLE from fear to acceptance, and patients with college education or higher (OR 2.09, 95% CI 1.10-4.04) were associated with a positive attitude toward SLE. CONCLUSIONS: A large proportion of patients seeking health care in the provincial capital cities of China migrated from other cities. Persistent monitoring of potential AEs and chronic diseases during SLE treatment and managing patients who changed hospitals for medical consultation are essential for controlling disease flares. Patients had insufficient knowledge about SLE treatment guidelines and would benefit from health education to maintain a positive attitude toward SLE.

Loss of Protein Kinase D2 Activity Protects Against Bleomycin-Induced Dermal Fibrosis in Mice.

Protein kinase D (PKD) has been linked to inflammatory responses in various pathologic conditions; however, its role in inflammation-induced dermal fibrosis has not been evaluated. In this study, we aimed to investigate the roles and mechanisms of protein kinase D2 (PKD2) in inflammation-induced dermal fibrosis and evaluate the therapeutic potential of PKD inhibitors in this disease. Using homozygous kinase-dead PKD2 knock-in (KI) mice, we examined whether genetic ablation or pharmacologic inhibition of PKD2 activity affected dermal inflammation and fibrosis in a bleomycin (BLM)-induced skin fibrosis model. Our data showed that dermal thickness and collagen fibers were significantly reduced in BLM-treated PKD2 KI mice compared with that in wild-type mice, and so was the expression of α-smooth muscle actin and collagens and the mRNA levels of transforming growth factor-ß1 and interleukin-6 in the KI mice. Corroboratively, pharmacologic inhibition of PKD by CRT0066101 also significantly blocked BLM-induced dermal fibrosis and reduced α-smooth muscle actin, collagen, and interleukin-6 expression. Further analyses indicated that loss of PKD2 activity significantly blocked BLM-induced infiltration of monocytes/macrophages and neutrophils in the dermis. Moreover, using bone marrow-derived macrophages, we demonstrated that PKD activity was required for cytokine production and migration of macrophages. We have further identified Akt as a major downstream target of PKD2 in the early inflammatory phase of the fibrotic process. Taken together, our findings indicate that PKD2 promotes dermal fibrosis via regulating immune cell infiltration, cytokine production, and downstream activation of Akt in lesional skin, and targeted inhibition of PKD2 may benefit the treatment of this condition.

Protein Kinase D2 and D3 Promote Prostate Cancer Cell Bone Metastasis by Positively Regulating Runx2 in a MEK/ERK1/2-Dependent Manner.

Advanced-stage prostate tumors metastasize to the bone, often causing death. The protein kinase D (PKD) family has been implicated in prostate cancer development; however, its role in prostate cancer metastasis remains elusive. This study examined the contribution of PKD, particularly PKD2 and PKD3 (PKD2/3), to the metastatic potential of prostate cancer cells and the effect of PKD inhibition on prostate cancer bone metastasis in vivo. Depletion of PKD2/3 by siRNAs or inhibition by the PKD inhibitor CRT0066101 in AR-positive and AR-negative castration-resistant prostate cancer cells potently inhibited colony formation and cell migration. Depletion or inhibition of PKD2/3 significantly blocked tumor cell invasion and suppressed the expression of genes related to bone metastasis in the highly invasive PC3-ML cells. The reduced invasive activity resulting from PKD2/3 depletion was in part mediated by the transcription factor Runx2, as its silencing decreased PKD2/3-mediated metastatic gene expression through the mitogen-activated protein kinase kinase/extracellular signal-regulated kinase 1/2 signaling axis. Furthermore, inhibition of PKD by CRT0066101 potently decreased the frequency of bone micrometastases in a mouse model of bone metastasis based on intracardiac injection of PC3-ML cells. These results indicate that PKD2/3 plays an important role in the bone metastasis of prostate cancer cells, and its inhibition may be beneficial for the treatment of advanced prostate cancer.

A retrospective cohort study in Chinese patients with adult polymyositis and dermatomyositis: risk of comorbidities and subclassification using machine learning.

OBJECTIVES: To identify the risk factors in Chinese patients with adult polymyositis and dermatomyositis for their comorbidities and explore a subclassification system. METHODS: Clinical records of 397 patients with idiopathic inflammatory myopathies were retrospectively reviewed. Logistic regression was used to identify potential risk factors for interstitial lung disease (ILD), other rheumatic diseases, and malignancy after bivariate analysis. Hierarchical clustering and decisional tree were utilised to identify subgroups and explore a subclassification system. RESULTS: A total of 119 polymyositis and 191 dermatomyositis patients were included. Anti-PM/Scl, anti-Ro52, anti-aminoacyl-tRNA synthetase and anti-MDA5 (adjusted odds ratios (AOR)=4.779, 1.917, 5.092 and 7.714 respectively) antibodies were risks (p<0.05), whereas overlapping malignancy was protective (AOR=0.107; p=0.002) for ILD across polymyositis, dermatomyositis and the total group. In subgroup models, Raynaud's phenomenon, arthralgia and semi-quantitative anti-nuclear antibody (AOR=51.233, 4.261, 3.047 respectively) were risks for other overlapping rheumatic diseases (p<0.05). For overlapping malignancy, male and anti-TIF1γ antibodies (AOR=2.533, 16.949) were risks (p<0.05), whereas disease duration and combination of ILD (AOR=0.954, 0.106) were protective in the total group (p<0.05); while anti-NXP2 antibodies were identified as risk factors (AOR=73.152; p=0.038) in polymyositis. Hierarchical clustering suggested a subclassification with 6 subgroups: malignancy overlapping dermatomyositis, classical dermatomyositis, polymyositis with severe muscle involvement, dermatomyositis with ILD, polymyositis with ILD, and overlapping of myositis with other rheumatic diseases. CONCLUSIONS: Accompanying ILD, other rheumatic diseases and malignancy are strongly associated with clinical manifestation and myositis-specific or myositis-associated autoantibodies among Chinese polymyositis and dermatomyositis patients. The subclassification system proposed a more precise phenotype defining toward stratified treatments.

Identification of Circular RNAs Circ_0005008 and Circ_0005198 in Plasma as Novel Biomarkers for New-Onset Rheumatoid Arthritis.

The progression of autoimmune diseases is affected by the differential expression of circular RNAs (circRNAs). However, in the plasma from rheumatoid arthritis (RA), circRNAs have an uncertain role. Herein, microarray analysis was used to determine the plasma expression profile of circRNAs from new-onset patients with RA and healthy controls (HCs). CircRNA expression was verified using quantitative real-time reverse transcription PCR. The correlation between clinical variables and circRNA expression was assessed using Spearman's correlation test. The diagnostic value of plasma circRNAs was evaluated using receiver operating characteristic (ROC) curves. Circ_0005008 and circ_0005198 were confirmed to be elevated significantly in plasma samples from new-onset patients with RA compared with those from HCs and from patients with systemic lupus erythematosus. Among these new-onset patients with RA, we found that the levels of circ_0005008 and circ_0005198 correlated positively with the severity of disease, including the rheumatoid factor, C-reactive protein, the erythrocyte sedimentation rate, and the disease activity score in 28 joints (DAS28). However, their expression levels did not correlate with anti-cyclic citrullinated peptide antibodies. Analysis using ROC curves implied that circ_0005008 and circ_0005198 have significant value in the diagnosis of RA. In addition, we found that compared with that in osteoarthritis fibroblast-like synoviocytes (OA-FLSs), circ_0005198 expression was enhanced in RA-FLSs and correlated positively with DAS28. The level of the miRNA target of circ_0005198, miR-4778-3p, was identified as significantly decreased in RA-FLSs, and the expression levels of circ_0005198 and miR-4778-3p correlated significantly and negatively. The results suggested that in new-onset patients with RA, plasma circ_0005008 and circ_0005198 levels are associated with disease activity and represent possible RA biomarkers.

Association between IL-33 and other inflammatory factors in patients with rheumatoid arthritis and in fibroblast-like synoviocytes in vitro.

IL-33 is a member of the IL-1 family of cytokines whose role remains controversial in rheumatoid arthritis (RA). The present study was performed to evaluate the correlation of IL-33 with other cytokines and chemokines in serum and the synovia, and to explore the nature of the association. The concentration of IL-33 in samples from 96 patients with RA was analyzed. The response of fibroblast-like synoviocytes (FLSs) to treatment with different concentrations of IL-33 was assessed in vitro. IL-33 was indicated to exhibit an association with multiple cytokines and chemokines in synovial fluid with an inverted-U-shaped trend, including IL-6, IL-1ß, IL-8, MIG and IP-10, but not in the serum. Furthermore, in vitro experiments confirmed that IL-33 also exerted a U-type dose-dependent regulatory effect on FLS function. In addition, the data-points do not exactly follow the U-shaped curve fit in most cases, therefore, the applicability of this mathematical model in clinical practice is limited.

Hsa_circ_0088036 promotes the proliferation and migration of fibroblast-like synoviocytes by sponging miR-140-3p and upregulating SIRT 1 expression in rheumatoid arthritis.

Circular RNAs (circRNAs) have been demonstrated to play crucial roles in the development and progression of various types of cancers by serving as microRNA sponges to regulate the expression of target genes. Although in-depth studies of circRNAs have been conducted, their functional and pathological significance in autoimmune diseases, including rheumatoid arthritis (RA), remains unclear. Our previous study verified that hsa_circ_0088036 (circ0088036) is significantly elevated in peripheral blood mononuclear cells from patients with RA. The present study aimed to explore the roles of circ0088036 in the pathogenesis of RA. The circ0088036/miR-140-3p/silent information regulator 1 (SIRT 1) axis was predicted by bioinformatics tools. Circ0088036 was found to be aberrantly upregulated in fibroblast-like synoviocytes (FLSs) in RA compared with FLSs in osteoarthritis (OA). Functionally, upregulated circ0088036 promoted the proliferation and migration of RA-FLSs. Mechanistically, circ0088036 acted as a miR-140-3p sponge to upregulate SIRT 1 expression, subsequently promoting RA progression. In conclusion, this study revealed that circ0088036 may play an essential role in promoting synovial pathogenesis via the circ0088036/miR-140-3p/SIRT 1 axis in RA, providing new insight into circRNAs during RA progression.

Transforming growth factor ß1 promotes fibroblast-like synoviocytes migration and invasion via TGF-ß1/Smad signaling in rheumatoid arthritis.

Migration and invasion are important characteristics of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLSs), which are involved in joint damage and contribute to rheumatoid arthritis (RA) pathology. However, the underlying mechanisms remain unclear. Because epithelial-mesenchymal transition (EMT) is a key mechanism related to migration and invasion in cancer cells, we investigated the relationship between EMT and RA-FLSs and explored whether the transforming growth factor ß1 (TGF-ß1)/Smad signaling pathway is involved. In vivo, fibroblast-like synoviocytes (FLSs) were isolated from the synovium of RA or osteoarthritis (OA) patients and cultured for 4-8 passages. EMT markers were detected by immunofluorescence and Western blotting. RA-FLSs were treated with TGF-ß1 or Smad2/3 small interfering RNA (siRNA), EMT markers were detected, and migration and invasion were assessed by Transwell assays. EMT markers could be detected in FLSs; when compared with osteoarthritis fibroblast-like synoviocytes (OA-FLSs), E-cadherin and vimentin decreased, while N-cadherin and α-smooth muscle actin (α-SMA) increased in RA-FLSs. Furthermore, TGF-ß1 enhanced migration and invasion by inducing EMT via activating Smad2/3 in RA-FLSs. Phosphorylation of Smad2/3 was accompanied by degradation of Smad3. Silencing Smad2/3 blocked EMT and inhibited the migration and invasion induced by TGF-ß1. Matrix metalloproteinase 9 (MMP9) and vimentin were not affected when cells were treated with TGF-ß1 or Smad2/3 siRNA. The TGF-ß1/Smad signaling pathway is involved in EMT and contributes to migration and invasion in RA-FLSs. Interestingly, vimentin decreased in RA-FLSs, but there is no correlation between vimentin and TGF-ß1/Smad signaling pathway. Thus, further research on vimentin should be conducted.

Long-term prognosis and quality of life in patients with early rheumatoid arthritis treated according to the 2015 ACR guideline (LELAND): protocol for a multicentre prospective observational study in Southern China.

INTRODUCTION: Rheumatoid arthritis (RA) is a chronic systemic disease and one of the most disabling diseases for patients. The American College of Rheumatology (ACR) issued a new guideline in 2015 for the treatment of RA based on the treat-to-target strategy to achieve better outcomes. This study will focus on the real-world rates of remission and low disease activity of patients with early RA in China, who will be treated according to the 2015 ACR guideline. Additionally, factors influencing treat-to-target outcomes will be analysed, and long-term prognosis and quality of life will be assessed. METHOD AND ANALYSIS: Two-hundred patients with early RA will be enrolled, treated and followed up once every 3 months for 48 months. These patients should fulfil the 2010 RA classification criteria of the ACR/European League Against Rheumatism with a disease course of no more than 6 months and should also fulfil other eligibility criteria. The patients will be treated following the 2015 ACR guideline. Their disease activity will be assessed, and they will be instructed to complete several questionnaires once every 3 months. The primary outcomes are the Disease Activity Score on 28 joints and Health Assessment Questionnaire Disability Index. The secondary outcome variables are the Simplified Disease Activity Index, Clinical Disease Activity Index and Routine Assessment of Patient Index Data 3 results, imaging data and personal medical costs. The data will be analysed using appropriate statistical analyses. ETHICS AND DISSEMINATION: This research was approved by the Nanfang Hospital Ethics Committee (NFEC-2017-192). The results of the study will be published in international peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03508713; Pre-results.

Using plasma circRNA_002453 as a novel biomarker in the diagnosis of lupus nephritis.

This study aimed to determine the expression of circRNAs in plasma from lupus nephritis (LN) patients to identify novel biomarkers for LN screening. We initially performed microarray screening of circRNA changes in plasma from 5 L N patients, 5 systemic lupus erythematosus (SLE) patients without LN, and 5 healthy controls. We then confirmed the selected circRNA changes in plasma from 59 SLE patients (30 with LN and 29 without LN), 26 rheumatoid arthritis (RA) patients, and 27 age- and sex-matched controls using real-time quantitative reverse transcription-polymerase chain reaction. Spearman's correlation test was performed to assess the correlation of circRNAs and clinical variables. The receiver operating characteristic (ROC) curve was created to evaluate the diagnostic value. We confirmed that plasma circRNA_002453 was significantly elevated in LN patients when compared with SLE patients without LN, RA patients, and healthy controls. Plasma circRNA_002453 was also found to be upregulated in SLE patients when compared with RA patients and healthy controls. Among these LN patients, we detected no significant correlation between plasma circRNA_002453 and disease activity, including complement 3 (C3), complement 4 (C4), and SLE disease activity index 2000 (SLEDAI-2 K) score. However, its expression level was significantly and positively correlated with 24-hour proteinuria (r = 0.571, p = 0.001) and renal SLEDAI score (r = 0.640, p < 0.001). ROC analysis showed that plasma circRNA_002453 had an area under the curve of 0.906 (95% CI 0.838-0.974, p < 0.001) to discriminate LN patients from controls (SLE patients without LN, RA patients, and healthy controls) with sensitivity of 0.900 and specificity of 0.841. The highest Youden index was 0.741 and the corresponding optimal cut-off value was 0.001. This study suggests that upregulated plasma circRNA_002453 level in LN patients is associated with the severity of renal involvement and may also serve as a potential biomarker for LN patient diagnosis.

MicroRNA­198 contributes to lupus nephritis progression by inhibition of phosphatase and tensin homology deleted on chromosome ten expression.

A number of short noncoding microRNAs (miRs) have been demonstrated to be highly expressed in many kidney diseases such as renal cancer and lupus nephritis (LN); however, these results have not been extensively investigated. The aim of the present study was to investigate the expression and function of miR­198 in LN based on the previous studies. miR­198 expression level in systemic lupus erythematosus (SLE) patients was determined to determine its clinicopathological significance and effect on glomerular cell proliferation. It was demonstrated that higher expression of miR­198 was observed in patients with SLE, and was correlated with disease activity. Bioinformatics prediction and luciferase assays were used to demonstrate that miR­198 could directly bind to the phosphatase and tensin homology deleted on chromosome ten (PTEN) 3'­untranslated region. Furthermore, miR­198 overexpression reduced PTEN expression levels, while miR­198 silencing increased its expression at both the mRNA and protein level. Furthermore, there was a negative association between miR­198 and PTEN in the patients with active SLE. Thus, miR­198 may promote proliferation and contribute to SLE progression by targeting PTEN.

Microarray Expression Profile of Circular RNAs in Peripheral Blood Mononuclear Cells from Rheumatoid Arthritis Patients.

BACKGROUND/AIMS: Circular RNAs (circRNAs) compose a large class of RNAs that can be used as biomarkers in clinical blood samples. This study aimed to determine the expression of circRNAs in peripheral blood mononuclear cells (PBMCs) from rheumatoid arthritis (RA) patients to identify novel biomarkers for RA screening. METHODS: We started with a microarray screening of circRNA changes in PBMCs from 5 RA patients and 5 healthy controls. We then confirmed the selected circRNA changes in PBMCs from 30 RA patients and 25 age- and sex-matched controls using the real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Spearman correlation test was performed to assess the correlation of circRNAs and clinical variables. Receiver operating characteristic (ROC) curve was calculated to evaluate the diagnostic value. RESULTS: We identified and verified five circRNAs (092516, 003524, 103047, 104871, 101873) that were significantly elevated in PBMCs from RA patients. Among these RA patients, we detected no significant correlation between the five circRNAs and the disease severity, including disease activity score (DAS28), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and health assessment questionnaire (HAQ). Yet, ROC curve analysis suggested that circRNA_104871 has significant value of RA diagnosis (AUC=0.833, P<0.001), followed by circRNA_003524 (AUC = 0.683, P = 0.020), circRNA_101873 (AUC = 0.676, P = 0.026), and circRNA_103047 (AUC = 0.671, P = 0.030). CONCLUSIONS: This study suggests that increased expression of circRNAs circRNA_104871, circRNA_003524, circRNA_101873 and circRNA_103047 in PBMC from RA patients may serve as potential biomarkers for RA patient diagnosis.

Overexpression of Srcin1 contributes to the growth and metastasis of colorectal cancer.

The adaptor protein Srcin1 is a novel Src-binding protein that regulates Src activation through C-terminal Src kinase (Csk). Srcin1 behaves as a tumour suppressor in breast cancer, but the role of Srcin1 in the development of colorectal cancer (CRC) remains unknown. In the present study, Srcin1 expression in normal tissue was examined by tissue microarray and assessed by immunohistochemistry in 10 patients. In addition, the biological impact of Srcin1 knockdown on CRC cells was investigated in vitro and in vivo. The results showed that Srcin1 was expressed in different types of normal human tissues, whereas its expression was increased in human CRC tissues. Srcin1 expression also correlated with tumour progression. The suppression of Srcin1 induced cell differentiation and G0/G1 cell cycle arrest. Furthermore, Srcin1 increased cell growth as well as the capacity of migration and invasion in CRC cells. Srcin1 induced the activation of the Wnt/ß-catenin signalling pathway. Moreover, Srcin1 suppression sensitized cancer cells to 5-fluorouracil (5-FU)-induced apoptosis in vitro and in vivo. Together, these results demonstrate that Srcin1 contributes to CRC carcinogenesis, invasion and metastasis. These findings provide a rationale for a mechanistic approach to CRC treatment based on the development of Srcin1-targeted therapies.

Rufy3 promotes metastasis through epithelial-mesenchymal transition in colorectal cancer.

Rufy3 is a RUN domain-containing protein that has been associated with gastric cancers; however, the role of Rufy3 in the progression of colorectal cancer (CRC) remains unknown. We demonstrated that Rufy3 expression was higher in 11/12 fresh CRC tissues than in adjacent normal tissues. Rufy3 induced elevated expression and transactivity of four major oncogenes in CRC. Moreover, siRNA-mediated repression of Rufy3 induced G0/G1 cell cycle arrest, and Rufy3 overexpression enhanced CRC cell proliferation in vitro and in vivo. Furthermore, Rufy3 up-regulation promoted epithelial-mesenchymal transition (EMT) and metastatic phenotypes. Using an established in vitro cell model of 5-fluorouracil-resistant (5-FU) CRC cells, we assessed cellular morphology, molecular changes, and invasion and found that these characteristics were consistent with EMT. Silencing of Rufy3 by siRNA reversed EMT and greatly diminished the invasion of 5-FU-treated cells. In addition, TGF-ß1 induced Rufy3 expression in a dose-dependent manner, and Rufy3 knockdown inhibited TGF-ß1-induced EMT. In vivo, higher expression of Rufy3 promoted CRC cell invasion and metastasis and induced EMT. Taken together, this work identified that Rufy3 promoted cancer metastasis in CRC cells through EMT induction.

Direct regulation of FOXK1 by C-jun promotes proliferation, invasion and metastasis in gastric cancer cells.

Forkhead box (FOX) K1 is a member of the FOX transcription factor superfamily. High FOXK1 expression is associated with several cancers. However, whether FOXK1 expression contributes to gastric cancer (GC) development and progression remains unknown. We analyzed the FOXK1 promoter using the Promo software and found several binding sequence transcription factors, including c-jun. However, the molecular mechanism by which FOXK1 affects the c-jun-mediated malignant phenotype is poorly understood. Here, we found that FOXK1 protein expression was higher in 8/10 (80.0%) fresh cancer tissues compared with that in adjacent normal tissues. FOXK1 overexpression enhanced the proliferation, migration and invasion of GC cells. Moreover, FOXK1 expression was stimulated by transforming growth factor-ß1 (TGF-ß1). FOXK1 acted as a potential epithelial-to-mesenchymal transition (EMT) inducer by stimulating vimentin expression and inducing the loss of E-cadherin in stable FOXK1-transfected cells. The results of promoter reporter and chromatin immunoprecipitation assays demonstrated that c-jun directly binds to and activates the human FOXK1 gene promoter. A positive correlation was observed between the expression patterns of FOXK1 and c-jun in GC cells and tissue. FOXK1 and c-jun expression were correlated with tumor progression and represented significant predictors of overall survival in GC patients. However, the siRNA-mediated repression of c-jun in FOXK1-overexpressing cells reversed EMT, as well as the proliferative and metastatic phenotypes. In vivo, c-jun promoted FOXK1-mediated proliferation and metastasis via orthotopic implantation. The evidence presented here suggests that FOXK1-directed regulation by c-jun promote the development and progression of human GC.

Decline of recent seabirds inferred from a composite 1000-year record of population dynamics.

Based on three ornithogenic sediment profiles and seabird subfossils therein from the Xisha Islands, South China Sea, the relative population size of seabirds over the past 1000 years was reconstructed using reflectance spectrum. Here we present an apparent increase and subsequent decline of seabirds on these islands in the South China Sea. Seabird populations peaked during the Little Ice Age (LIA, 1400-1850 AD), implying that the cool climate during the LIA appears to have been more favorable to seabirds on the Xisha Islands in the South China Sea. Climate change partly explains the recent decrease in seabird populations over the past 150 years, but the significant decline and almost complete disappearance thereof on most of the Xisha Islands is probably attributable to human disturbance. Our study reveals the increasing impact of anthropogenic activities on seabird population in recent times.

Knockdown of FOXK1 alone or in combination with apoptosis-inducing 5-FU inhibits cell growth in colorectal cancer.

Forkhead box K1 (FOXK1) is a member of the FOX transcription factor family, which plays an important role in oncogenesis. However, the exact function and mechanism of FOXK1 in human colorectal cancers (CRCs) remain unclear. In the present study, we first screened for potential FOXK1 target genes by ectopically expressing FOXK1 in SW480 cells and examined the subsequent changes in the expression levels of major oncogenes using RT-PCR. We also evaluated the effects of FOXK1 regulation on growth and apoptosis. In addition, we investigated the biological impact of FOXK1 knockdown on CRC cells in vitro and in vivo. We found that FOXK1 overexpression increased the expression of multiple oncogenes in vitro. FOXK1 promoted serum-dependent and anchorage-dependent and -independent cell growth. Knockdown of FOXK1 induced G0/G1 cell cycle arrest in CRC cells. Moreover, FOXK1 suppression induced apoptosis and increased cell susceptibility to 5-fluorouracil (5-FU)-induced apoptosis. Furthermore, a xenograft model was established to explore FOXK1 shRNA-mediated tumorigenesis in vivo. A strong antitumorigenic effect of FOXK1-shRNA was enhanced when combined with 5-FU treatment. These findings implicate FOXK1 as a cell cycle and growth modulator that inhibits apoptosis in colon cancer cells. FOXK1-shRNA may serve as a novel and potent therapeutic agent, alone or with 5-FU, against colon cancer.

A protocol for the culture and isolation of murine synovial fibroblasts.

The culture of synovial fibroblasts (SFs) is one of the most effective tools for investigating the pathology and physiology of synovial tissues and should prove useful for identifying the importance of SFs in disease as well as for the development of novel therapeutic approaches for several chronic joint diseases, such as rheumatoid arthritis. However, thus far, a detailed protocol for the primary culture and isolation of murine SFs has not been established. Therefore, the present study describes an easy and convenient method for isolating and culturing SFs from C57BL/6 mice. This protocol can be divided into 4 stages: Isolation of synovial tissues, isolation of SFs, seeding of SFs for growth in culture and purity analysis of SFs using the four cell markers, vimentin, cluster of differentiation 90.2 (CD90.2; Thy-1.2), intracellular adhesion molecule 1 (CD54) and vascular cell adhesion molecule 1 (CD106). This method is efficient and a purified population of SFs can be obtained 10 days after the initiation of culture.

Oncogene FOXK1 enhances invasion of colorectal carcinoma by inducing epithelial-mesenchymal transition.

Transcriptional factor FOXK1 is a member of the FOX family, involved in the cell growth and metabolism. The higher expression of FOXK1 leads to a variety of diseases and may play an important role in the development of various tumors. However, the role of FOXK1 in the progression of colorectal cancer (CRC) remains unknown. We demonstrated that FOXK1 was overexpressed in 16 types of solid tumor tissues via tissue multi-array (TMA). We found that FOXK1 induced elevated expressions and transactivities of five major oncogenes in CRC. Moreover, the elevated expression of FOXK1 was showed to be correlated with tumor progression and was a significant predictor of overall survival in CRC patients. Furthermore, it was showed that the depletion of FOXK1 expression could inhibit the migratory and invasive abilities of CRC cells. In contrast, ectopic expression of FOXK1 elicited the opposite effects on these phenotypes in vitro. FOXK1 promoted tumor metastasis through EMT program induction. In addition, TGF-ß1 induced FOXK1 expression in a time-dependent pattern and the knockdown of FOXK1 inhibited TGF-ß1-induced EMT. In vivo, higher expression of FOXK1 promotes CRC cell invasion and metastasis, and induces EMT in CRC as well. Alltogether, it was concluded that the higher expression of FOXK1 could indicate a poor prognosis in CRC patients since that FOXK1 induces EMT and promotes CRC cell invasion in vitro and in vivo.