PLK1-activating IFI16-STING-TBK1 pathway induces apoptosis of intestinal epithelial cells in patients with intestinal Behçet's syndrome

Inflammatory signals from immunological cells may cause damage to intestinal epithelial cells (IECs), resulting in intestinal inflammation and tissue impairment. Interferon-γ-inducible protein 16 (IFI16) was reported to be involved in the pathogenesis of Behçet's syndrome (BS). This study aimed to investigate how inflammatory cytokines released by immunological cells and IFI16 participate in the pathogenesis of intestinal BS. RNA sequencing and real-time quantitative PCR (qPCR) showed that the positive regulation of tumor necrosis factor-α (TNF-α) production in peripheral blood mononuclear cells (PBMCs) of intestinal BS patients may be related to the upregulation of polo like kinase 1 (PLK1) in PBMCs (P = 0.012). The plasma TNF-α protein level in intestinal BS was significantly higher than in healthy controls (HCs; P = 0.009). PBMCs of intestinal BS patients and HCs were co-cultured with human normal IECs (NCM460) to explore the interaction between immunological cells and IECs. Using IFI16 knockdown, PBMC-NCM460 co-culture, TNF-α neutralizing monoclonal antibody (mAb), stimulator of interferon genes (STING) agonist 2'3'-cGAMP, and the PLK1 inhibitor SBE 13 HCL, we found that PLK1 promotes the secretion of TNF-α from PBMCs of intestinal BS patients, which causes overexpression of IFI16 and induces apoptosis of IECs via the STING-TBK1 pathway. The expressions of IFI16, TNF-α, cleaved caspase 3, phosphorylated STING (pSTING) and phosphorylated tank binding kinase 1 (pTBK1) in the intestinal ulcer tissue of BS patients were significantly higher than that of HCs (all P < 0.05). PLK1 in PBMCs of intestinal BS patients increased TNF-α secretion, inducing IEC apoptosis via activation of the IFI16-STING-TBK1 pathway. PLK1 and the IFI16-STING-TBK1 pathway may be new therapeutic targets for intestinal BS.

Clinical heterogeneity and five phenotypes identified in pediatric Behçet's syndrome: a cohort study from Shanghai Behçet's syndrome database

OBJECTIVES

Behçet's syndrome (BS) is a rare disease of unknown etiology, with limited reports especially in pediatric BS. The clinical characteristics and phenotypes of pediatric BS as a highly heterogeneous variable vessel vasculitis were investigated in this study.

METHODS

A cross-sectional study was conducted to compare clinical variables and descriptive characteristics of BS by age of onset and gender. Cluster analysis was then performed to identify the phenotypes of pediatric BS.

RESULTS

A total of 2082 BS patients were included in this study, 1834 adults and 248 children. Compared with adult-onset BS, pediatric BS had a higher incidence of folliculitis [relative risks (RR) and 95% confidence interval (CI) 1.3 (1.0-1.5)], uveitis of the left eye [RR and 95% CI 2.3 (1.0-5.0)], intestinal ulcer complications [RR and 95% CI 2.1 (1.1-4.2)], pericarditis [RR and 95% CI 2.5 (1.0-6.2)], and psychiatric disorders [RR and 95% CI 2.8(1.0-7.9)], while the incidence of thrombocytopenia was lower [RR 0.2 (0.1-1.0)]. Among pediatric BS, females had more genital ulcers, while males were more likely to have skin lesions, panuveitis, vascular involvement, venous lesions, cardiac involvement, and aortic aneurysms. Cluster analysis classified pediatric BS into five clusters (C1-C5): C1 (n = 61, 24.6%) showed gastrointestinal (GI) involvement; C2 (n = 44, 17.7%) was the central nervous system (CNS) type where 23 cases overlapped joint involvement; in C3 (n = 35, 14.1%), all patients presented with arthritis or arthralgia; all patients in C4 (n = 29, 11.7%) manifested ocular involvement, with a few patients overlapping with GI involvement or joint damage; C5 (n = 79, 31.9%) was the mucocutaneous type, presenting both oral ulcers, genital ulcers, and skin lesions.

CONCLUSIONS

The clinical features of pediatric and adult BS differ significantly. Male and female pediatric BS also have a distinct demography. Five phenotypes including GI, CNS, joint, ocular, and mucocutaneous types were identified for pediatric BS.

The roles of immune cells in Behçet's disease

Behçet's disease (BD) is a systemic vasculitis that can affect multiple systems, including the skin, mucous membranes, joints, eyes, gastrointestinal and nervous. However, the pathogenesis of BD remains unclear, and it is believed that immune-inflammatory reactions play a crucial role in its development. Immune cells are a critical component of this process and contribute to the onset and progression of BD. By regulating the function of these immune cells, effective control over the occurrence and development of BD can be achieved, particularly with regards to monocyte activation and aggregation, macrophage differentiation and polarization, as well as T cell subset differentiation. This review provides a brief overview of immune cells and their role in regulating BD progression, which may serve as a theoretical foundation for preventing and treating this disease.

Comprehensive analysis of T-cell receptor repertoires reveals antigen-driven T-cell clusters in patients with Behçet's syndrome

T lymphocytes are the major components of adaptive immunity in Behçet's syndrome (BS) pathology. However, the precise mechanism of T-cell-induced inflammatory condition remains to be determined. We applied bulk sequencing of the T-cell receptor (TCR) β chain in peripheral blood samples from 45 patients with BS and 10 healthy donors as controls. TCR repertoires in BS patients displayed more clonality and less diversity than in healthy donors. Male patients exhibited lower diversity metrics of TCR and had a larger proportion in the top 10 clones than females (p = 0.016). There were no TCR clonality differences in other clinical features, such as age, disease duration, organ involvement, disease severity, and activity. By "Grouping of Lymphocyte Interactions by Paratope Hotspots" (GLIPH2) for antigen prediction, we found distinct 2477 clusters of TCR-β sequences that potentially recognize similar antigens shared between BS patients. We observed clonal T-cell expansion in BS patients. Sexual differences in TCR clonal expansion and public TCR groups deserve further study to reveal the underline T-cell-mediated immunity in BS.

Predictors of infliximab refractory intestinal Behçet's syndrome: A retrospective cohort study from the Shanghai Behçet's syndrome database

OBJECTIVES

This retrospective cohort study aimed to find out predictors and early biomarkers of Infliximab (IFX) refractory intestinal Behçet's syndrome (intestinal BS).

METHODS

We collected the baseline clinical characteristics, laboratory parameters, and concomitant therapies of intestinal BS patients treated by IFX from the Shanghai Behçet's syndrome database. After 1 year IFX therapy, intestinal BS patients with non-mucosal healing (NMH, intestinal ulcers detected by colonoscopy) and/or no clinical remission [NCR, scores of the disease activity index for intestinal Behçet's disease (DAIBD) ≥20] were defined as IFX refractory intestinal BS. Multivariate logistic regression analysis was performed to evaluate the predictors for NMH and NCR in IFX refractory intestinal BS.

RESULTS

In 85 intestinal BS patients, NMH was identified in 29 (34.12%) patients, and NCR was confirmed in 20 (23.53%) patients. Erythrocyte sedimentation rate (ESR; ≥24 mm/h) and free triiodothyronine (fT3; ≤3.3pmol/L) were the independent risk factors of NMH in IFX refractory intestinal BS. Drinking alcohol and the fT3/free thyroxine ratio (fT3/fT4; ≤0.24) were independent risk factors, and thalidomide was an independent protective factor, for NCR in intestinal BS patients treated by IFX.

CONCLUSION

This study may be applicable for adjusting the therapeutic strategy and sidestepping unnecessary exposure to IFX in intestinal BS patients. Routine assessments of ESR, fT3, and fT3/fT4 ratio are helpful to identify high-risk individuals of IFX refractory intestinal BS. Thalidomide is suggested to be a concomitant therapy with IFX for intestinal BS patients.

Tofacitinib as an alternative therapy for refractory intestinal Behçet's syndrome

Background:

Intestinal Behçet’s syndrome is a major cause of morbidity and mortality in Behçet’s syndrome.

Objectives:

Current treatment challenges remain in refractory intestinal Behçet’s syndrome, when patients failed first and second-line therapies.

Design:

We reported the efficacy and safety profiles of tofacitinib in patients with moderate-severe intestinal Behçet’s syndrome in a retrospective single-center study.

Methods:

Treatment with glucocorticoids, immunosuppressors, or even anti-TNFα monoclonal antibodies (mAbs) had previously failed. Primary outcomes were clinical remission or low disease activity and endoscopic healing.

Results:

We included 13 patients; 11 were administered tofacitinib 5 mg twice daily, and 2 took tofacitinib 5 mg once daily. Nine patients achieved clinical remission after a mean treatment duration of 10.1 ± 7.0 months, and the other four had low disease activity. Follow-up endoscopy was available in 11 patients: 5 had achieved mucosal healing; the other 4 achieved marked mucosal improvement. Prednisone dosage was significantly reduced, from 30 (interquartile range: 20–30) mg/d to 2.5 (interquartile range: 0–12.5) mg/d (p < 0.001). No serious adverse event was observed.

Conclusion:

Tofacitinib could be an efficacious and generally well-tolerated option in patients with intestinal Behçet’s syndrome refractory to conventional agents, even anti-TNFα mAbs.

Clinical heterogeneity of ocular Behçet's syndrome versus intestinal Behçet's syndrome: a cross-sectional study from Shanghai Behçet's syndrome database

Background

Behçet’s syndrome (BS) is a rare variant vasculitis which can involve the eyes and gastrointestinal systems. However, ocular involvement rarely overlaps with intestinal lesions. This study aimed to compare the clinical characteristics and laboratory parameters of ocular BS and intestinal BS patients in China and analyze the differences between two key phenotypes to verify the heterogeneous conditions in BS patients.

Methods

A retrospective analysis was used to collect the demographic data, clinical characteristics, endoscopic findings, and laboratory parameters from 135 ocular BS and 174 intestinal BS patients. The Mann-Whitney U test and Pearson chi-square or continuity correction was used to analyze the differences between two groups.

Results

Among 916 BS patients enrolled in this study, ocular BS and intestinal BS accounted for 14.74% (135 cases) and 19.00% (174 cases), respectively. Ocular and intestinal involvements overlapped in only 7 cases (0.76%). Male gender (74.8% vs. 51.1%, P=0.00), erythema nodosum (45.9% vs. 32.2%, P=0.01), and vascular involvement (6.7% vs. 1.7%, P=0.03) were more frequent in the ocular BS group compared with the intestinal BS group. On the contrary, hematologic involvement (7.5% vs. 0.0%, P=0.00) and fever (17.8% vs. 4.4%, P=0.00) were more frequent in the intestinal BS group compared with the ocular BS group. Additionally, the inflammation markers including ESR [26.5 (16.0–41.5) vs. 9.0 (5.0–15.0) mm/H, P=0.00], CRP [14.8 (4.8–33.0) vs. 4.1 (1.6–8.3) mg/L, P=0.00], serum amyloid A [27.4 (10.8–92.3) vs. 11.3 (6.0–24.0) mg/L, P=0.00], and interleukin 6 [8.4 (1.7–18.7) vs. 1.7 (1.5–3.2) pg/mL, P=0.00] were higher in the intestinal BS group than those in the ocular BS group, respectively.

Conclusions

Ocular BS was more prevalent in male patients and more likely to manifest with erythema nodosum and vascular involvement, while intestinal BS tends to have fever and hematologic disorders with higher inflammation markers. Ocular BS and intestinal BS are two distinct clinical phenotypes and very rarely overlapped.

New insight into the features of Behçet's disease with gastrointestinal ulcer: a cross-sectional observational study

BACKGROUND

Behçet's disease (BD) can involve any site of the alimentary canal. There has been research concerning intestinal BD. Nevertheless, the entire digestive tract not yet been studied extensively. Therefore, the purpose of study was to describe the prevalence, location, clinical features and possible risk factors of BD with gastrointestinal tract ulcer.

METHODS

This was a cross-sectional observational study that included 1232 consecutive BD patients who routinely underwent endoscopy upon their wishes. The clinical symptoms, endoscopic findings, and histologic features of BD with gastrointestinal ulcer and negative Helicobacter pylori (Hp) were identified.

RESULT

We found that 22.16% (273/1232) BD patients had ulcers of the alimentary tract. At presentation, 61.54% (168/273) patients were asymptomatic. Isolated gastroduodenal involvement is an extremely usual event. The second was the pairwise combination between bowel segments, and 24 cases involved three segments at the same time. One patient suffered from total gastrointestinal tract involvement. Inflammation was the most common histopathologic feature 77.60% (142/183). The 273 BD patients with gastrointestinal ulcer were at greater risk of having archenteric symptoms (OR 0.070, P < 0.001), fever (OR 0.115, P = 0.047), high CRP (OR 0.994, P = 0.027) and BDCAF level (OR 0.590, P = 0.010). Uveitis correlates negatively with gastrointestinal involvement in BD patients (OR 3.738, P = 0.011).

CONCLUSIONS

BD could affect the upper gastrointestinal tract independently. Endoscopy should be conducted in all patients in whom a diagnosis of BD is entertained, especially in patients with higher CRP, disease activity and fever. While, BD patients with uveitis correlates negatively with gastrointestinal involvement.

Epidemiology of Takayasu arteritis in Shanghai: A hospital-based study and systematic review

BACKGROUND

Takayasu arteritis (TAK) is a rare large vessel vasculitis, and epidemiological data on TAK are lacking in China. Thus, we designed this study to estimate the TAK prevalence and incidence in residential Shanghai, China.

METHODS

Data on diagnosed TAK cases aged over 16 years were retrieved from 22 tertiary hospitals in Shanghai through hospital electronic medical record systems between January 1, 2015 and December 31, 2017 to estimate the prevalence and incidence. A systematic literature review based on searches in PubMed, Ovid-Medline, Excerpta Medica Database (EMBASE), Web of Science, and China National Knowledge Infrastructure (CNKI) was performed to summarize TAK distribution across the world.

RESULTS

In total 102 TAK patients, with 64% female, were identified. The point prevalence (2015-2017) was 7.01 (95% CI 5.65-8.37) cases per million, and the mean annual incidence was 2.33 (1.97-3.21) cases per million. The average age of TAK patients was 44 ± 16 years, with the highest prevalence (11.59 [9.23-19.50] cases per million) and incidence (3.55 [0.72 3.74] cases per million) in the 16 to 34 years population. Seventeen reports were included in the system review, showing that the epidemiology of TAK varied greatly across the world. The incidence and prevalence were both relatively higher in Asian countries, with the prevalence ranging 3.3-40 cases per million and annual incidence ranging 0.34-2.4 cases per million.

CONCLUSIONS

The prevalence and incidence of TAK in Shanghai was at moderate to high levels among the previous reports. The disease burden varied globally among racial populations.

Clinical characteristics and risk factors of intestinal involvement in Behçet's syndrome patients: a cross-sectional study from a single center

BACKGROUND

Intestinal Behçet's syndrome (BS) has high morbidity and mortality rates with serious complications. The purpose of this study was to investigate the clinical characteristics and laboratory parameters of intestinal and mucocutaneous BS patients and analyze the risk factors of intestinal involvement in BS patients.

METHODS

A retrospective analysis was used to collect the demographic data and laboratory parameters from 97 intestinal and 154 mucocutaneous BS patients. Univariate and multivariate logistic regression analyses were used to investigate the risk factors of intestinal involvement in BS patients.

RESULTS

The most common clinical manifestations of first onset in intestinal BS patients were oral ulceration (100.00%), followed by genital ulcers (62.89%) and erythema nodule (28.87%), gastrointestinal lesions (28.87%), pseudofolliculitis (25.77%), fever (17.53%), arthritis (16.49%), ocular involvement (5.15%), while the least common were vascular involvement (2.06%) and hematologic involvement involvement (2.06%). The most common intestinal segment involved in intestinal BS patients was terminal ileum (30.9%), followed by ileocecal (18.6%), colon (15.5%). By univariate logistic regression analysis, gender, age at hospitalization, age of disease onset, BDCAF, T-SPOT, fever, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), leukocyte, erythrocyte, hemoglobin (HGB), neutrophil-to-lymphocyte ratio, serum amyloid A, complement 3, albumin, total cholesterol, high-density lipoprotein and interleukin 6 (IL-6) were found all risk factors of intestinal involvement in BS patients (P < 0.05 or P = 0.00). Moreover, gender (male), BDCAF (≥ 2), ESR (≥ 15 mm/H), CRP (> 10 mg/L), HGB (< 130 g/L) and IL-6 (> 7 pg/ml) were found the independent risk factors of intestinal involvement in BS patients (all P < 0.05).

CONCLUSIONS

More attention shall be paid to gender, BDCAF, ESR, CRP, HGB and IL-6 in BS patients. When gender (male), BDCAF (≥ 2), ESR (≥ 15 mm/H), CRP (> 10 mg/L), HGB (< 130 g/L) and IL-6 (> 7 pg/ml) being observed, it may reminds that the presence of intestinal involvement in BS patients.

Distinct clinical characteristics of pediatric Behçet's syndrome: A study from a referral center in China

OBJECTIVES

To describe the clinical features and patterns of phenotype aggregation in pediatric Behçet's syndrome (BS) in a tertiary center in China.

METHODS

This was a cross-sectional study of consecutive BS patients in Huadong Hospital, Fudan University between September 2012 and January 2020. Pediatric BS was defined as diagnosed before 16 years old. We compared clinical variables between pediatric and adult patients. We calculate relative risks (RRs) of clinical variables according to sex. Moreover, a hierarchical cluster analysis was undertaken according to 29 clinical variables to determine homogeneous subgroups.

RESULTS

From 1596 consecutive BS cases, we identified 69 pediatric BS. Compared with adult-diagnosed BS, pediatric-diagnosed patients had a higher frequency of folliculitis [RR 1.57 (95% CI 1.12, 2.20)], a lower frequency of arthralgia [RR 0.15 (95% CI 0.02, 1.07)] and panuveitis [RR 0.43 (95% CI 0.18, 1.03)], no cardiac lesion. There was an association between male and arterial thrombosis or aneurysms (p = .006). A cluster analysis stratified three sub-clusters (C1-C3): C1 (n = 30) showed a disease type merely affecting skin and mucosa. C2 (n = 20) represented the gastrointestinal type; most patients presented with intestinal involvement, and two cases with esophageal ulcers. In C3 (n = 19), showing a mixture of uveitis, vascular and central nervous system (CNS) involvement, six patients presented with uveitis and nine had vascular lesions, and three cases had CNS lesions.

CONCLUSION

We conducted a comprehensive statistical analysis in a cohort of pediatric patients with BS in China. Less ocular involvement and no cardiac lesions were observed in childhood-diagnosed patients. For the first time, three distinct phenotype subgroups in pediatric-diagnosed patients were identified by cluster analysis.Key messagesThis study demonstrated the phenotype discrepancy between childhood and adult-diagnosed BS.Three distinct clusters were identified, with skin-mucosa, gastrointestinal, panuveitis, vascular and CNS subgroups.

Cluster analysis of phenotypes of patients with Behçet's syndrome: a large cohort study from a referral center in China

INTRODUCTION

Behcet's syndrome (BS) is a complex, heterogeneous disorder. However, classification of its subgroups is still debated. The purpose of this study was to investigate the clinical features and aggregation of patients with BS in China, based on manifestations and organ involvements.

METHODS

This was a cross-sectional study of BS patients in Huadong Hospital of Fudan University between September 2012 and January 2020. We calculated relative risks (RRs) of clinical variables according to sex. Moreover, we conducted a hierarchical cluster analysis applied according to eighteen variables to determine subgroups of patients.

RESULTS

A total of 860 BS patients were included. Male sex was associated with ocular involvement (RR 2.32, 95% CI 1.67, 3.22, P < 0.0001), vascular involvement (RR 2.00, 95% CI 1.23, 3.23, P = 0.004), cardiac lesion (RR 5.46, 95% CI 2.33, 12.77, P < 0.0001), and central nervous system involvement (RR 2.95, 95% CI 1.07, 6.78, P = 0.007) and was negatively associated with genital ulcers (RR 0.84, 95% CI 0.79, 0.91, P < 0.0001). Five clusters (C1-C5) were observed. C1 (n = 307) showed the skin and mucosa type. In C2 (n = 124), all had articular involvement, barely having major organ involvement except for 18 cases with intestinal lesions. In C3 (n = 156), the gastrointestinal type, 144 patients presented with intestinal involvement, and 36 patients with esophageal ulcers. In C4 (n = 142), all subjects presented with uveitis. C5 (n = 131) consisted of 44 patients with cardiac lesions, 58 with vascular involvement, and 26 cases having central nervous system involvement.

CONCLUSION

Our analysis confirmed sex differences in phenotypes of BS. Cluster analysis identified gastrointestinal, uveitis, and cardiovascular involvement cluster separately in different subsets, which represents the most commonly involved organs. Further research is required to replicate and clarify the patterns of phenotype in BS.

Characteristics and phenotype heterogeneity in late-onset Behçet's syndrome: a cohort from a referral center in China

OBJECTIVES

To evaluate the demographics, clinical aspects, and major organ involvement of patients with late-onset Behçet's syndrome (BS) in a tertiary center in China.

METHODS

We conducted a cross-sectional study of consecutive BS patients in Huadong Hospital of Fudan University from September 2012 to January 2020. We compared clinical variables between patients with disease onset before and after 40 years of age. The relative risks (RRs) of clinical variables were calculated between the two age groups. Moreover, a hierarchical cluster analysis was conducted according to 29 variables to determine homogeneous subgroups in patients with late-onset BS.

RESULTS

We enrolled 152 late-onset BS patients, with a median age at onset of 47 years (interquartile range, IQR: 43-52 years). There is a higher prevalence of intestinal ulcers in late-onset BS than in early-onset BS (RR 1.47), but a lower prevalence of ocular involvements (RR 0.54) and folliculitis (RR 0.46). Female sex was associated with genital ulcers, erythema nodosum, and arthritis. Four clusters (C1-C4) were formed. C1 (n = 71), the largest cluster, was defined as the mucocutaneous group, C2 (n = 20) as the arthritis group, C3 (n = 39) as the gastrointestinal group, in which all patients presented with intestinal lesions, and five cases with esophageal ulcers. In C4 (n = 22), showing a mixture of uveitis and vascular lesions, 15 patients presented with uveitis and 8 had vascular lesions, and 1 case had central nervous system lesions.

CONCLUSION

Four phenotype clusters were identified. Patients with skin lesions comprised the largest cluster, while gastrointestinal, panuveitis, and cardiovascular clusters are the most commonly involved organs in late-onset BS patients. Key Points • Our analysis demonstrated the phenotype discrepancy between early and late onset groups. • Four phenotype clusters were identified, with gastrointestinal, panuveitis and cardiovascular clusters representing commonly involved organs.

Clinical characteristics and factors influencing the prognosis of Behçet’s disease complicated with vascular involvement

Summary: Background: Vascular Behçet's disease (VBD) might involve all sizes of arterial and venous vessels. Major vascular involvement caused the primary death in Behçet's syndrome (BS). We aimed to investigate the clinical characteristics and factors influencing the prognosis of VBD. Patients and methods: A retrospective analysis of the prospectively collected data of the Shanghai BS database from October 2012 to October 2018 was conducted. Patients who were diagnosed with BS and merged with venous thrombosis, arterial aneurysms, and arterial stenosis/occlusions were enrolled. Results: There were 47 patients with vascular involvement among 836 BS patients, 38 males and 9 females. The numbers of patients with venous thrombosis, arterial aneurysm, and arterial stenosis/occlusion were 25 (53.2 %), 21 (44.7 %), and 12 (25.5 %), respectively. Nearly half of the venous thromboses were located in limbs (n = 22, 46.8 %). Arterial aneurysm was the main form of arterial lesion. Most of the patients (93.6 %) were treated with corticosteroids and immunosuppressants. Late onset of BS or with arterial involvement had lower treatment response. Therapy with biological agents had significantly better results than that in the group without biological treatment (94.1 % vs. 80 %, P = 0.005). Conclusions: VBD showed a male preponderance and more than half of the patients presented with venous thrombosis. Late onset and arterial involvement were associated with poor prognosis. Therapy with biological agents is a viable alternative treatment to improve the prognosis.

Evaluation of factors for predicting risk of uveitis recurrence in Behcet's disease patients

This study aimed to investigate the predictive factors for uveitis recurrence (UR) risk in Behcet's disease (BD) patients. BD patients (n=164) with a history of uveitis were recruited, and demographic data, clinical features, and laboratory tests were recorded. Uveitis was defined as anterior uveitis, intermediate uveitis, posterior uveitis, panuveitis referring to the "International Uveitis Study Group recommendations for the evaluation of intraocular inflammatory disease". In total, there were 70 UR patients and 94 non-UR patients. Compared to non-UR patients, UR patients appeared to be older and presented with increased uveitis occurrence rate and times within 3 months, oral ulcers occurrence rate, as well as higher concentrations of triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL), and serum amyloid A (SAA). Multivariate logistic model disclosed that uveitis occurrence times within 3 months, oral ulcers, TG, LDL, and SAA independently predicted higher risk of UR. Furthermore, receiver operating characteristic curve analysis showed that the combination of uveitis occurrence times within 3 months, oral ulcers, TG, LDL, and SAA exhibited a high predictive value for UR risk with an area under the curve of 0.983 (95%CI: 0.969-0.998). In conclusion, uveitis occurrence times within 3 months, oral ulcers, TG, LDL, and SAA might be potential predictive factors for UR risk in BD patients, which can help in prevention and management of the disease.

Poor prognostic factors in patients with newly diagnosed intestinal Adamantiades-Behçet's disease in the Shanghai Adamantiades-Behçet's disease database: a prospective cohort study

BACKGROUND

Adamantiades-Behçet's Disease (ABD) is an immunological recurrent systemic vasculitis with a chronic course. We investigated the predictors of long-term flare-ups, poor outcomes and event-free survival in Chinese non-surgical patients with intestinal ABD.

METHODS

This was a prospective cohort study of 109 intestinal ABD patients seen in our institution between October 2012 and January 2019 who met the international criteria for ABD and had intestinal ulcers confirmed on colonoscopy. Predictors of relapses and poor outcomes, event-free survival were calculated using logistic regression models and Cox proportional hazard regression models, respectively.

RESULTS

Sixty-six intestinal ABD patients (60.55%) had ileocecal ulcers; 19 patients (17.43%) presented with colorectum ulcers; 24 patients (22.02%) showed both ileocecal and colorectum ulcers. 7 patients (6.42%) experienced at least 1 flare-up of intestinal ulcers. 38 patients (34.86%) complained of non-healing intestinal ulcers. In multivariate analysis, location of intestinal ulcers (ileocecal and colorectum) (odd ratio (OR) 7.498 [95% confidence interval [95% CI] 1.844-30.480]), erythrocyte sedimentation rate (ESR) > 24 mm/h (OR 5.966 [95% CI 1.734-20.528]), treatment with infliximab (IFX) (OR 0.130 [95% CI 0.024-0.715]), and poor compliance (OR 11.730 [95% CI 2.341-58.781]) were independently correlated with a poor outcome. After a median follow-up of 28 months, 45 intestinal ABD patients (41.28%) underwent adverse events. Factors independently associated with shorter event-free survival were early onset of ABD (< 7 years) (hazard ratio (HR) 2.431 [95% CI 1.240-4.764]) and poor compliance (HR 3.058 [95% CI 1.612-5.800]).

CONCLUSION

Distribution of intestinal ulcers (ileocecal and colorectum), ESR > 24 mm/h, treatment without IFX, and poor compliance were independent risk factors for poor outcomes in non-surgical intestinal ABD patients.

The T-SPOT.TB assay used for screening and monitoring of latent tuberculosis infection in patients with Behçet's disease pre- and post-anti-TNF treatment: A retrospective study

BACKGROUND

Patients undergoing anti-tumor necrosis factor (TNF) treatment are more susceptible to latent tuberculosis infection (LTBI). The aim of the current study was to determine the rate of active tuberculosis (TB) in patients with Behçet's disease (BD) pre- and post-anti-TNF treatment and to evaluate the long-term efficacy of LTBI screening as primary prophylaxis in China.

METHODS

This retrospective study included BD patients eligible for anti-TNF therapy at a single institution in Fudan University, China. On the basis of the results of T-SPOT.TB assay, chest radiograph, and history of exposure to TB, patients were screened and regularly followed up at 3-months interval.

RESULTS

Eighty-nine BD patients with mean disease duration of 87.5 ± 86.1 months were included. Their median duration of anti-TNF therapy was 10.6 months; 51 patients were treated with Infliximab, 38 with Etanercept, and four with Adalimumab. While 84 patients received a consecutive single anti-TNF drug therapy, five patients switched to a second drug. Twelve patients demonstrated positive results in LTBI screening: three had history of TB exposure and nine were solely T-SPOT.TB-positive patients. Before anti-TNF treatment, LTBI treatment was initiated in 11 patients, and one patient refused treatment. With a median follow-up period of 27.9 months, we observed only one case (1.1%) of intestinal TB during Infliximab treatment.

CONCLUSION

Regardless of anti-TNF treatment, long-term screening via T-SPOT.TB assay might represent a more sensitive approach to identify BD patients with LTBI. As a secondary prophylaxis, the LTBI treatment is effective in a country with high risk of TB.

Demography of vascular Behcet's disease with different gender and age: an investigation with 166 Chinese patients

Background

The Clinical features of vascular Behcet’s disease (BD) are not well understood because there are few studies. Our study aimed to investigate characteristics of vascular BD in both genders in different age groups.

Results

We enrolled 923 patients with BD who presented to our hospital with adequate medical histories and proper vascular screening exams. The raw incidence rate of vascular BD was 17.98% (166/923). The ratio of vascular BD in male to female patients was 1.868 (p = 0.0004, 95% confidence interval (CI): 1.317 to 2.625). There was a tendency towards higher ESR and CRP in vascular BD patients than in mucocutaneous, but the difference was not significant. The most susceptible affected vessels were cerebral (29.6% in males, 59.4% in females) and lower limb vessels (31.2% in males, and 17.2% in females). The incidence of vascular involvement in younger (< 50 years old) and older (≥ 50 years old) patients were similar, with ratios of 16.58% (122/736) and 23.53% (44/187) respectively. However, in females, younger patients were less likely to have vascular involvement than were older patients (11.43% vs. 20% p = 0.0328, OR: 0.5161, 95% CI: 0.2874 to 0.912). Aneurysm or pseudoaneurysm was diagnosed in 1.84% (17/923) patients, mostly in male patients (p < 0.05, OR: 3.221, 95% CI: 1.097 to 9.112). Twenty vascular BD patients were followed up, and the age at BD diagnosis was 33.23 ± 11.56 year. This did not differ statistically with their age at vascular involvement (36.15 ± 9.52 years). Ages of vascular BD patients did not differ significantly from those of mucocutaneous BD patients (n = 143) in both males and females.

Conclusion

Vascular BD, including lethal types of aneurysm is more likely to occur in male patients. The female patients has a similar incidence rate with the males in their postmenopausal age. There was no evidence of progression course from mucocutaneous BD to vascular involvement.

Incidence and risk factors for anemia among newly-diagnosed intestinal Behcet's disease patients

BACKGROUND

To investigate the incidence, characteristics, and potential risk factors of anemia in patients with newly-diagnosed intestinal Behcet's disease (BD).

METHODS

In this cross-sectional study, 106 newly-diagnosed intestinal BD patients were identified, and a gender-, age- and organ involvement-matched control group of 241 non-intestinal BD patients was established. Hemoglobin (Hb) levels below 120 g/L in women and 130 g/L in men were diagnosed as anemia; these were further classified as mild (Hb ≥ 90 g/L), moderate (60  g/L ≤ Hb < 90  g/L), and severe (Hb < 60 g/L) anemia for both genders. The prevalence, type and severity of anemia in these patients were assessed. Logistic regression was performed to analyze the relationship between clinical variables and anemia in newly-diagnosed intestinal BD patients.

RESULTS

The prevalence of anemia was 60.38% in newly-diagnosed patients with intestinal BD, significantly higher than those with non-intestinal BD (27.80%). Patients with intestinal BD had lower Hb, higher levels of C-reactive protein (CRP) and higher erythrocyte sedimentation rates (ESR) than did patients with non-intestinal BD (P < 0.05). The majority of patients had mild-to-moderate anemia. The most common type of anemia found in both groups was normocytic normochromic anemia (56.25% for intestinal BD and 59.70% for non-intestinal BD). Multivariate logistic regression showed that the independent risk factors for anemia were disease activity index (DAIBD) (OR = 4.949, 95% CI: 1.504-16.282), higher levels of ESR (OR = 1.058, 95% CI: 1.019-1.099), and lower body mass index (BMI) (OR = 0.843, 95% CI: 0.727-0.977) for newly-diagnosed intestinal BD patients.

CONCLUSION

Anemia is common in patients with newly-diagnosed intestinal BD. Although typically mild or moderate, anemia may closely relate with disease activity.

Serum uric acid could be served as an independent marker for increased risk and severity of ascending aortic dilatation in Behçet's disease patients

OBJECTIVE

This study aimed to investigate the correlation of serum uric acid (SUA) with risk and dilatation diameter of ascending aortic dilatation (AAD) in Behçet's disease (BD) patients.

METHODS

Seventeen BD patients complicated with AAD and 20 BD patients without AAD were consecutively enrolled and categorized into AAD group and control group, respectively. Ascending aortic dilatation was determined by two-dimensional doppler echocardiographic examination, and AAD was defined as a diameter of ascending aorta ≥3.8 and <4.4 cm. SUA was detected by quantitative immunoassay method.

RESULTS

Ascending aortic dilatation patients presented with higher proportion of male patients (P = 0.003), hypertension occurrence (P = 0.036) and increased diameter of ascending aorta (P < 0.001) compared to controls. SUA was elevated in AAD patients compared to controls (P = 0.002), and receiver operating characteristic curve displayed that SUA presented with great predictive value for AAD risk in BD patients with area under curve (AUC) 0.821 (95% CI 0.675-0.966). Pearson's analysis also disclosed that SUA was positively correlated with ascending aortic diameter in total BD patients. However, no difference of CRP (P = 0.219) or ESR (P = 0.320) between AAD patients and controls was observed, and no correlation of CRP (R = -0.150, P = 0.377) or ESR (R = 0.067, P = 0.692) with ascending aortic diameter in total BD patients was discovered either. Further multivariate logistic regression illuminated that SUA was an independent factor predicting AAD risk in BD patients (P = 0.031).

CONCLUSIONS

Serum uric acid could be served as an independent marker for increased risk and severity of AAD in BD patients.

Effectiveness and safety of Glycyrrhizae Decoction for Purging Stomach-Fire in Behcet disease patients: Study protocol for a randomized controlled and double-blinding trail

BACKGROUND

Behcet disease (BD) is a worldwide-occurred autoimmune disorder and currently lack of optional successful treatment. An ancient traditional Chinese medical formula called Glycyrrhizae Decoction for Purging Stomach-Fire (GDPSF) was recorded and nowadays has been observed to be effective for BD patients. However, the strict randomized controlled and double-blinding trail is needed to further assess this alternative medicine.

METHODS

To ascertain the potential effects and safety of GDPSF for BD patients and to determine whether combination application of GDPSF and thalidomide could possibly reduce the side effects and increase effectiveness for BD management, we will conduct a randomized, double blind, controlled clinical trial. Patients enrolled will be randomly assigned into 3 groups: GDPSF group, thalidomide group, and integrative group (treated by both GDPSF and thalidomide). Participants will receive treatment for 6 months and accept a 12 months follow-up. Before and after treatment, clinical manifestations, blood tests, thalidomide dosage, remission levels, quality of life, and satisfactory levels will be assessed. The data of assessments on each group before and after treatments will be collected and analyzed through historical control, while between groups through intergroup control. Then statistical analysis will be applied to assess the effects and safety.

DISCUSSION

This study protocol will assess the effects and safety of GDPSF for BD patients GDPSF. Combination application of GDPSF and thalidomide might be a new integrative medical method for BD patients.

TRIAL REGISTRATION

Chinese Clinical Registry (ChiCTR-ONC-16009621) on Oct. 2016 http://www.chictr.org.cn/showproj.aspx?proj=16395.

Mucosal Healing at 14 Weeks Predicts better Outcome in Low-dose Infliximab Treatment for Chinese Patients with Active Intestinal Behcet's Disease

AIMS

To compare the efficacy and the safety of low-dose (3.5 mg/kg) or standard-dose (5 mg/kg) of infliximab (IFX) for induction and maintenance treatment in Chinese patients with intestinal Behcet's disease (BD), and to identify potential predictors to corticosteroid-free clinical remission at week 30.

METHODS

A prospective trial was conducted in 20 patients with moderate-to-severe active intestinal BD, followed up for 30 weeks. Ileocolonoscopic examinations were done at baseline and week 14. A logistic regression model was used to assess the predictors of corticosteroid-free remission at week 30.

RESULTS

As the primary end point, steroid-free remission at week 30 was observed in 40% and 60% of patients who received low and standard doses of IFX, respectively (P>0.371). As the secondary end point, the mucosal healing (MH) rates at week 14 were found to be 60% for both low and standard doses of IFX. The clinical response rates at week 14 and 30 were also similar in both groups. Only MH at week 14 predicted steroid-free clinical remission at week 30.

CONCLUSIONS

Low-dose of IFX is effective and safe for induction and maintenance therapy in patients with active intestinal BD. MH at week 14 predicted clinical remission at week 30.

Long-Term Outcomes and Predictors of Sustained Response in Patients with Intestinal Behcet's Disease Treated with Infliximab

BACKGROUND

Intestinal Behcet's disease (BD) is a specific subtype of BD. Effective drug therapy for intestinal BD remains elusive.

AIMS

To investigate long-term outcomes and identify predictors of sustained response in intestinal BD patients receiving infliximab (IFX) treatment.

METHODS

The medical records were reviewed of patients received IFX from September 2012 to March 2016. The cumulative probabilities of sustained response were calculated using the Kaplan-Meier. Predictor factors for sustained response were accessed by receiver operating characteristic curve.

RESULTS

Totally, 27 active intestinal BD patients were enrolled. Sustained responses were observed in 17 patients, after a median follow-up duration 24 months (interquartile range 9-37). The proportion of clinical remission at week 14, 30, and 52 had occurred in 84.6, 70, and 70%, respectively, with the proportion of clinical remission of 69.2, 40, and 55%. The mucosal healing (MH) rate at week 14 was 72%. Kaplan-Meier estimated patients with achievement of clinical and biological responses at week 14 or MH was likely to remain sustained clinical response. ROC curve analysis revealed CRP level (of 6.85 mg/L) at week 14 is a potential predictor for discriminating patients with sustained response from relapse, with an area under the curve values of 0.837.

CONCLUSIONS

IFX is effective and safe for induction and maintenance therapy in Chinese patients with moderate-to-severe active intestinal BD. Early achievement of clinical response and mucosal healing might associate long-term response. A lower CRP level seems to be associated with a more benign clinical course.

[Progression of Behcet's disease with brain involvement: a case report]

Behcet's disease is a condition characterized by systemic vasculitis liable to thrombosis, and may involve the parenchyma and blood vessels in the brain. We report a case of Behcet's disease that progressed into central neural system involvement rapidly due to failure of tertiary prevention. This case demonstrates the importance of management of the high risk factors of thrombosis and timely prevention of disease progression.

Association of Reduced Heme Oxygenase-1 with Decreased MicroRNA-196a2 Expression in Peripheral Blood Mononuclear Cells of Patients with Intestinal Behcet's Disease

AIMS

To examine the expression of miRNAs and mRNAs of heme oxygenase 1 (HO-1) in patients with active intestinal Behcet's disease (BD).

METHODS

Peripheral blood mononuclear cells (PBMCs) were obtained from BD patients with active ileocecal ulcers or from healthy donors. Expression levels of four miRNAs were studied using real-time PCR. The levels of mRNAs of ho-1, bach1, and CD14 were measured by qRT-PCR. Serum levels of cytokines were analyzed by ELISA.

RESULTS

Among four miRNAs, only levels of miR-196a2 were significantly decreased from BD patients with active ileocecal ulcers as compared with healthy controls. Moreover, level of mRNA ho-1 expression in PBMCs from patients with BD was reduced. No significant difference on bach1 and CD14 mRNA levels was observed. Levels of IFN-γ, IL-17, IL-10, IL-1β, and TNF-α were higher in patients with active intestinal BD than those in healthy controls.

CONCLUSION

The present results suggest that miR-196a2 expression is decreased in active intestinal BD patients. Down regulated miR-196a2 may be involved in intestinal BD pathogenesis by targeting Bach1/ho-1. Consequently, pro-inflammatory cytokines are closely implicated in the evolution of intestinal BD.

Endoscopic findings of gastrointestinal involvement in Chinese patients with Behcet’s disease

AIM: To report the incidence, clinical features and outcomes of gastrointestinal (GI) involvement in Behcet’s disease (BD).

METHODS: A total of 168 consecutive patients with BD were screened and upper and lower GI endoscopies were performed in 148 patients. Four hundred age- and sex-matched controls were enrolled for comparison.

RESULTS: Fifty-two (35.1%) patients had GI lesions. After a mean follow-up of 10 mo, ileocecal ulcers had been confirmed in 20 patients, including active ulcer(s) in 18 patients, but no ileocecal ulceration was found in controls. GI symptoms were present in 14 patients with active ulcer(s), while 4 patients with smaller ulcer were asymptomatic. Endoscopic features of ileocecal ulcer were: a single ulcer (50%), larger than 1 cm in diameter (72.2%), and round/oval or volcano-type in shape (83.3%). Compared with patients without GI involvement, less ocular lesions, lower levels of albumin, erythrocyte count and hemoglobin, and higher levels of C-reactive protein and erythrocyte sedimentation rate were confirmed in the intestinal BD group. Four patients had esophageal ulcers in the BD group but no case in controls. The other endoscopic findings were similar between the two groups. The prevalence of Helicobacter pylori infection was similar in both groups. Most patients received an immunomodulator and responded well.

CONCLUSION: GI lesions commonly occur in Chinese BD patients. The most frequently involved area is the ileocecal region. Esophageal ulcer might be a rare but unique lesion.

Intercellular adhesion molecule-1 polymorphisms in patients with Behçet disease: a meta-analysis

OBJECTIVES

To examine the association between the Intercellular adhesion molecule-1 (ICAM1) Polymorphisms and Behçet's disease.

METHODS

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials for original studies up to July 31, 2012 were searched for relevant studies. All pooled odds ratios (ORs) were derived from either fixed or random-effects model with its 95% confidence intervals (CI).

RESULTS

Five studies met the inclusion criteria. Overall, ICAM1 E469 (OR = 1.45, 95% CI = 1.06-1.97), genotype ICAM1 469 E/E (OR = 1.45, 95% CI = 1.09-1.94), ICAM1 241 G/R (OR = 3.65, 95% CI = 1.69-7.89), had significant associations with Behçet's disease. A significant association was found between the presence of skin lesions and genotype ICAM1 469 E/E (OR = 3.52, 95% CI = 1.62-7.66).

CONCLUSIONS

Behçet's disease was associated with the ICAM1 E469, genotype ICAM1 469 E/E, ICAM1 241 G/R polymorphisms in different ethnic groups. Among patients, genotype ICAM1 469 E/E had a significant association with skin lesion.

Interleukin-1-related genes polymorphisms in Turkish patients with Behçet disease: a meta-analysis

OBJECTIVES

Polymorphisms in the Interleukin (IL)-1-related genes at the locations -889, -511, + 3962 and mspa1l 1100 have been investigated for possible association with Behçet's disease (BD).

METHODS

A literature-based search was conducted to identify all relevant studies. Five independent studies from Turkish population met the included criteria.

RESULTS

IL-1α -889 CT [odds ratio (OR) = 0.72, 95% confidence interval (CI) = 0.55-0.95], IL-1α -889 TT (OR = 0.61, 95% CI = 0.40-0.93), IL-1β + 3962 C (OR = 1.41, 95% CI = 1.07-1.88), IL-1β + 3962 T (OR = 0.71, 95% CI = 0.53-0.94) IL-1β + 3962 CC (OR = 2.08, 95% CI = 1.08-3.99), IL-1β + 3962 CT (OR = 0.58, 95% CI = 0.38-0.88), IL-1 receptor antagonist (IL-1 Ra) mspa1l 1100 CT (OR = 0.69, 95% CI = 0.49-0.96), IL-1 Ra mspa1l 1100 TT (OR = 1.50, 95% CI = 1.08-2.08) had a significant association with BD. The pooled estimates for IL-1α -889 C, IL-1α -889 CC, IL-1α -889 T had a non-significant association with BD.

CONCLUSIONS

IL-1α -889 CT, IL-1α -889 TT, IL-1β + 3962 C, IL-1β + 3962 T, IL-1β + 3962 CC, IL-1β + 3962 CT, IL-1 Ra mspa1l 1100 CT, IL-1Ra mspa1l 1100 TT promoter polymorphisms may confer susceptibility to BD in Turkish population.

The risk factors for nosocomial infection in chinese patients with active rheumatoid arthritis in shanghai

Objective. To analyse the potential risk factors of nosocomial infections in patients with active rheumatoid arthritis (RA). Methods. A total of 2452 active RA patients at Hospitals in Shanghai between January 2009 and February 2011 were analyzed. Their demographic and clinical characteristics were compared with those without infection, and the potential risk factors were determined by logistic regression analysis. Results. Multivariate analysis indicated the gender (OR = 0.70, 95% CI 0.53–0.92), duration in hospital (OR = 1.03 , 95%CI 1.01–1.05), number of organs involved (OR = 0.82, 95%CI 0.72–0.92), number of disease-modifying antirheumatic drugs ((DMARDs) (OR = 1.22, 95%CI 1.061–1.40)), corticosteroid therapy (OR = 1.02, 95%CI 1.01–1.03), peripheral white blood cell counts ((WBC) (OR = 1.04, 95%CI 1.00–1.08)), levels of serum albumin (OR = 0.98, 95%CI 0.97–0.99), and C-reactive protein ((CRP) (OR = 1.03 , 95%CI 1.01–1.04)) that were significantly associated with the risk of infections. Conclusion. The female patients, longer hospital stay, more organs involved, more DMARDs, corticosteroid usage, high counts of WBC, lower serum albumin, and higher serum CRP were independent risk factors of infections in active RA patients.

[The predictive factors and unfavourable prognostic factors of interstitial lung disease in patients with polymyositis/dermatomyositis]

OBJECTIVE

To analyze the predictive factors and the unfavourable prognostic factors of interstitial lung disease (ILD) in patients with polymyositis (PM)/dermatomyositis (DM).

METHODS

The clinical data were collected from 87 inpatients with DM or PM, who were admitted to Shanghai Changhai Hospital from January 1997 to November 2006. The patients were divided into an ILD group and a non-ILD group. The clinical feature, incidence and prognosis of ILD were retrospectively analyzed. The clinical and laboratory data were analyzed by using the SPSS 13.0 software. The t-test and rank-sum test were used, depending on the measurement data. The enumeration data were analyzed with chi-square test. Logistic regression and Kaplan-Meier survival curve were used to analyze the correlative and prognostic factors of interstitial lung disease (ILD) in patients with PM/DM.

RESULTS

The incidence and mortality of ILD in PM/DM patients were 46% (40/87) and 40% (16/40), respectively. Compared with the non-ILD group, the age in the ILD group was markedly older [(54 +/- 13) years vs (45 +/- 18) years], and the percentages of fever (21/40 vs 7/47, chi2 = 14.00, P < 0.01), dysphagia (16/40 vs 8/47, chi2 = 5.71, P < 0.05), arthralgia (26/40 vs 9/47, chi2 = 18.89, P<0.01), Gottron's rash (14/40 vs 2/47, chi2 = 13.61, P <0.01) and heart impairment (26/40 vs 14/47, chi2 = 10.28, P <0.01) were significantly higher in the ILD group. The levels ofLDH [(472 +/- 285) IU vs (310 +/- 238) IU, t =2.86, P<0.01], ESR [(44 +/- 24) mm/1 h vs (26 +/- 24) mm/l h, t = 3.19, P <0.01] and immunoglobulin G [(18 +/- 9) g/L vs (14 +/- 5) g/L, t = 2.31, P <0.05] were statistically different between the two groups. By multivariate nonparametric logistic regression analysis, Gottron's rash, arthralgia, fever, and > or = 40 years of age were identified as predictors with relative risk ratio of 12.048, 7.812, 6.329 and 5.236 respectively. The unfavourable prognostic factors of ILD were Gottron' s rash (chi2 = 5.35, P <0.05), cardiac impairment (chi2 = 5.68, P < 0.05) and pulmonary fibrosis (chi2 = 5.42, P <0.05) by survival analysis.

CONCLUSION

The occurrence of ILD in PM/ DM patients was closely correlated to Gottron's rash, age > or = 40 years, arthralgia and fever. Gottron's rash, heart impairment and pulmonary fibrosis were poor prognosis factors of PM/DM patients complicated with ILD.

Focal adhesion kinase: protein interactions and cellular functions

Integrin-mediated cell adhesion to extracellular matrix (ECM) plays important roles in a variety of biological processes. Recent studies suggested that integrins mediate signal transduction across the plasma membrane via activating several intracellular signaling pathways. Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that has been shown to be a major mediator of integrin signal transduction pathways. Upon activation by integrins, FAK undergoes autophosphorylation as well as associations with several other intracellular signaling molecules. These interactions in the signaling pathways have been shown to regulation a variety of cellular functions such as cell spreading, migration, cell proliferation, apoptosis and cell survival. Recent progress in the understanding of FAK interactions with other proteins in the regulation of these cellular functions will be discussed in this review.

Immunoelectron microscopic study of beta-endorphinergic synaptic innervation of GABAergic neurons in the dorsal raphe nucleus

Using a preembedding double immunoreactive technique by immunostaining with antirat beta-endorphin and antisynthetic glutamic acid decarboxylase antisera sequentially, the synaptic relationships between beta-endorphinergic neuronal fibers and GABAergic neurons in the dorsal raphe nucleus of the rat were examined at the ultrastructural level. Although both beta-endorphin-like immunoreactive fibers and glutamic acid decarboxylase-like immunoreactive neurons can be found in the mediodorsal and medioventral parts of the dorsal raphe nucleus, the synapses between them were found only in the mediodorsal part. Most of the beta-endorphin-like immunoreactive neuronal fibers contained many dense-cored vesicles. The synapses made by beta-endorphin-like immunoreactive neuronal axon terminals on glutamic acid decarboxylase-like immunoreactive neurons were both symmetrical and asymmetrical, with the latter predominant, especially in the axo-dendritic synapses. Perikarya with beta-endorphin-like immunoreactivity were found only in the ventrobasal hypothalamus. These findings suggest the possibility that the beta-endorphin-producing neurons in the ventrobasal hypothalamus could influence GABAergic neurons in the dorsal raphe nucleus directly by synaptic relationships.

Transcriptional activation of cyclin D1 promoter by FAK contributes to cell cycle progression

Integrin-mediated cell adhesion to the extracellular matrix is required for normal cell growth. Cyclin D1 is a key regulator of G1-to-S phase progression of the cell cycle. Our previous studies have demonstrated that integrin signaling through focal adhesion kinase (FAK) plays a role in the regulation of cell cycle progression, which correlates with changes in the expression of cyclin D1 and the cdk inhibitor, p21, induced by FAK. In this report, we first investigated the roles of both cyclin D1 and p21 in the regulation of cell cycle progression by FAK. We found that overexpression of a dominant-negative FAK mutant DeltaC14 suppressed cell cycle progression in p21(-/-) cells as effectively as in the control p21(+/+) cells. Furthermore, we found that overexpression of ectopic cyclin D1 could rescue cell cycle inhibition by DeltaC14. These results suggested that cyclin D1, but not p21, was the primary functional target of FAK signaling pathways in cell cycle regulation. We then investigated the mechanisms underlying the regulation of cyclin D1 expression by FAK signaling. Using Northern blotting and cyclin D1 promoter/luciferase assays, we showed that FAK signaling regulated cyclin D1 expression at the transcriptional level. Using a series of cyclin D1 promoter mutants in luciferase assays as well as electrophoretic mobility shift assays (EMSA), we showed that the EtsB binding site mediated cyclin D1 promoter regulation by FAK. Finally, we showed that FAK regulation of cyclin D1 depends on integrin-mediated cell adhesion and is likely through its activation of the Erk signaling pathway. Together, these studies demonstrate that transcriptional regulation of cyclin D1 by FAK signaling pathways contributes to the regulation of cell cycle progression in cell adhesion.

The nonreceptor tyrosine kinase ACK2, a specific target for Cdc42 and a negative regulator of cell growth and focal adhesion complexes

ACK2 (activated Cdc42-associated tyrosine kinase-2) is a nonreceptor tyrosine kinase that is a specific target/effector for the GTP-binding protein Cdc42. Thus far the biological function of this tyrosine kinase has not been determined. Using an inducible eukaryotic expression system in fibroblasts, we demonstrate that ACK2 can strongly influence cell shape and growth as well as focal complex formation. ACK2 was found to associate with the focal adhesion complex components talin and vinculin, but not with the focal adhesion kinase (FAK), in a kinase-independent manner. The tyrosine kinase activity of FAK was also inhibited in cells overexpressing both wild-type and kinase-defective ACK2. This may be due to a competition between ACK2 and FAK for Src, which is an essential cofactor for FAK activation, as we have found that ACK2 specifically binds Src in cells. The ACK2-Src interaction appears to be mediated by the SH3 domain of Src, and the phosphorylation of ACK2 is enhanced in cells overexpressing the hyperactivated Src(Y527F) mutant. Overexpression of both wild-type and kinase-defective ACK2 also results in a severe inhibition of cell growth. In addition, ACK2 dissolves actin stress fibers and disassembles focal complexes but in a kinase-dependent manner. These results, taken together with previous studies demonstrating an association of ACK2 with integrin beta(1) (Yang, W., Lin, Q., Guan, J.-L., Cerione, R. A. (1999) J. Biol. Chem. 274, 8524-8530) and clathrin (Yang, W., Lo, C. G., Dispenza, T., and Cerione, R. A. (2001) J. Biol. Chem. 276, 17468-17473), suggest that the binding and protein tyrosine kinase activities of ACK2 coordinate changes in cell morphology and growth with the disassembly of focal adhesion sites, perhaps to organize new integrin complexes that are required for endocytosis and/or for cellular differentiation.

The Grb7 family proteins: structure, interactions with other signaling molecules and potential cellular functions

Grb7 family adaptor molecules consist of Grb7, Grb10 and Grb14, each of which has several splicing variants. Like other adaptor molecules, Grb7 family proteins function to mediate the coupling of multiple cell surface receptors to downstream signaling pathways in the regulation of various cellular functions. They share significant sequence homology with each other and a conserved molecular architecture including an amino-terminal proline-rich region, a central segment termed the GM region (for Grb and Mig) which includes a PH domain and shares sequence homology with the Caenorhabditis elegans protein, Mig-10, involved in embryonic migration, and a carboxyl-terminal SH2 domain. Grb7 family proteins are differentially expressed in a variety of tissues. They are phosphorylated on serine/threonine as well as tyrosine residues, although the kinases responsible have not been well characterized. Grb7 family proteins are mainly localized in the cytoplasm, but have been observed at the plasma membrane, focal contacts, or mitochondria under certain conditions. A large number of receptor tyrosine kinases and other signaling molecules can associate with Grb7 family proteins, mostly through the SH2 domains. Various isoforms of Grb10 have been shown to regulate cell proliferation and apoptosis, whereas Grb7 has been found to regulate cell migration and also implicated in tumor progression. Future studies of interests will include identification of potential downstream effectors of Grb7 family proteins as well as understanding of the mechanisms of specificity of the different family members in signal transduction.

Reciprocal synaptic relationships between angiotensin II-containing neurons and enkephalinergic neurons in the rat area postrema

A preembedding double immunostaining technique was used to study synaptic relationships between angiotensin-II-like immunoreactive and enkephalin-like immunoreactive neurons in the rat area postrema. The angiotensin-II-like immunoreactive neurons were detected by silver-gold intensification of the DAB reaction results while the enkephalin-like immunoreactive neurons were detected by simple ABC-DAB reaction. The synaptic relationships were reciprocal between the two neurons. Most of the synapses found between these two neurons were the presynaptic enkephalin-like immunoreactive axon terminals that made synapses on the angiotensin-II-like immunoreactive perikarya and dendrites. Both the axo-somatic and axo-dendritic synapses were symmetrical. However, although angiotensin-II-like immunoreactive axon terminals also made synapses on enkephalin-like perikarya and dendrites, the axo-somatic synapses were symmetrical, while the axo-dendritic synapses were asymmetrical. The present results confirm the presence of angiotensin-II-like immunoreactive neurons in the area postrema and suggest that these angiotensinergic neurons in the area postrema may play a role in the regulation of blood pressure via coordinated synaptic interactions with enkephalinergic neurons.

Differential regulation of cell migration and cell cycle progression by FAK complexes with Src, PI3K, Grb7 and Grb2 in focal contacts

Focal adhesion kinase (FAK) is a key mediator of integrin signaling, which has been implicated in the regulation of cell migration and cell cycle progression. Using chimeric molecules that fuse the focal adhesion targeting (FAT) sequence directly to several signaling molecules, we investigated the potential role of FAK recruitments of signaling molecules to focal contacts in the regulation of cell migration and cell cycle progression. We found that fusion of FAT to Src, the p85 subunit of phosphatidylinositol 3-kinase, Grb7 and Grb2 resulted in the efficient focal adhesion targeting of these signaling molecules. We showed that expression of Src-FAT, p85-FAT, or Grb7-FAT, but not Grb2-FAT, each stimulated cell migration. Interestingly, tyrosine phosphorylation of paxillin, but not p130cas, was induced by expression of Src-FAT, suggesting a potential role of paxillin in mediating stimulation of cell migration by the chimeric molecule. In contrast, targeting of Grb2, but not Src, p85, or Grb7, to focal contacts increased cell cycle progression. Biochemical analyses correlated Erk activation by Grb2-FAT with its stimulation of cell cycle progression. Together, these results suggest that at least part of the role of FAK interaction with these signaling molecules is to recruit them to focal contacts and that distinct FAK signaling complexes are involved in the regulation of cell migration vs. cell cycle progression.

Focal adhesion kinase activates Stat1 in integrin-mediated cell migration and adhesion

Recent studies suggest that focal adhesion kinase (FAK) is important for cell migration. We now suggest a mechanism by which FAK activates the signal transducer and activator of transcription (STAT) pathway, regulating cell adhesion and migration. In particular, we observe that FAK is capable of activating Stat1, but not Stat3. Co-immunoprecipitation and in vitro binding assays demonstrate that Stat1 is transiently and directly associated with FAK during cell adhesion, and Stat1 is activated in this process. FAK with a C-terminal deletion (FAKDeltaC14) completely abolishes this interaction, indicating this association is dependent on the C-terminal domain of FAK, which is required for FAK localization at focal contacts. Moreover, Stat1 activation during cell adhesion is diminished in FAK-deficient cells, correlating with decreased migration in these cells. Finally, we show that depletion of Stat1 results in an enhancement of cell adhesion and a decrease in cell migration. Thus, our results have demonstrated, for the first time, a critical signaling pathway from integrin/FAK to Stat1 that reduces cell adhesion and promotes cell migration.

Regulation of the PH-domain-containing tyrosine kinase Etk by focal adhesion kinase through the FERM domain

Etk/BMX, a member of the Btk family of tyrosine kinases, is highly expressed in cells with great migratory potential, including endothelial cells and metastatic carcinoma cell lines. Here, we present evidence that Etk is involved in integrin signalling and promotes cell migration. The activation of Etk by extracellular matrix proteins is regulated by FAK through an interaction between the PH domain of Etk and the FERM domain of FAK. The lack of Etk activation by extracellular matrix in FAK-null cells could be restored by co-transfection with wild-type FAK. Disrupting the interaction between Etk and FAK diminished the cell migration promoted by either kinase. Furthermore, inhibiting Etk expression in metastatic carcinoma cell lines with an antisense oligonucleotide blocks integrin-mediated migration of these cells. Taken together, our data indicate the essential role of the interaction of the PH domain of Etk and the FERM domain of FAK in integrin signalling.

Orexinergic innervation of POMC-containing neurons in the rat arcuate nucleus

A pre-embedding double immunostaining technique was used to study the synaptic relationships between orexin-like immunoreactive axon terminals and preopiomelanocortin (POMC)-like immunoreactive neurons in the rat arcuate nucleus. Most of the synapses were axo-dendritic, while some axo-somatic synapses were also found. Both the axo-somatic and axodendritic synapses were symmetrical. In some cases the presynaptic orexin-like immunoreactive axon terminals contained a few large dense-cored vesicles. The results suggest that the orexinergic axon terminals in the arcuate nucleus may play an important role in the regulation of food intake via synapses through POMC neurons.

Identification of a novel interaction between integrin beta1 and 14-3-3beta

Integrins are cell surface receptors for extracellular matrix, which play important roles in a variety of biological processes. 14-3-3 proteins are a highly conserved family of cytoplasmic proteins that associate with several intracellular signaling molecules in regulation of various cellular functions. Here, we report identification of an interaction between the integrin beta1 cytoplasmic domain and 14-3-3beta by using the yeast two-hybrid screen. Like several other proteins, the integrin beta1 cytoplasmic domain associated with 14-3-3beta by a non-phosphoserine mechanism. The 14-3-3beta/integrin beta1 interaction was confirmed by in vitro binding assays as well as co-precipitation in vivo. Furthermore, we found that 14-3-3beta co-localized with integrin beta1 during the early stage of cell spreading on fibronectin, suggesting a potential role of the 14-3-3beta/integrin beta1 interaction in the regulation of cell adhesion. Using tetracycline-regulated expression system, we showed that overexpression of 14-3-3beta stimulated cell spreading and migration on fibronectin but not on poly-L-lysine. However, the induced expression of 14-3-3beta did not affect tyrosine phosphorylation of FAK or its substrates, p130(cas) and paxillin, suggesting that 14-3-3beta regulated integrin-mediated cell spreading and migration by FAK-independent mechanisms. Taken together, these results identify an interaction between integrin and 14-3-3 proteins and suggest a potentially novel cellular function for 14-3-3 proteins in the regulation of integrin-mediated cell adhesion and signaling events.

Analysis of FAK-associated signaling pathways in the regulation of cell cycle progression

Focal adhesion kinase (FAK) is an important mediator of signal transduction pathways initiated by integrins in cell migration, survival and cell cycle regulation. The ability of FAK to mediate integrin signaling in the regulation of cell cycle progression depends on the phosphorylation of Tyr397, which implies a functional significance for the formation of FAK signaling complexes with Src, phosphatidylinositol-3-kinase (PI3K) and Grb7. We have previously described a FAK mutant, D395A, that selectively disrupts FAK binding to PI3K, but allows FAK association with Src. Using this mutation in a mislocalized FAK mutant background, we show here that formation of a FAK/PI3K complex is not sufficient for cell cycle progression but the formation of a FAK/Src complex plays an essential role. We also show that mutation of D395 to A disrupted FAK association with Grb7. This suggests that a FAK/Grb7 complex is not involved in the cell cycle regulation either, which is supported by direct analysis of cells expressing a dominant negative Grb7 construct. Finally, we provide evidence that the Src-dependent association of FAK with Grb2 and p130(Cas) are both required for the regulation of cell cycle progression by FAK. Together, these studies identify important FAK downstream signaling pathways in cell cycle regulation.

Observation of the ultrastructure and synaptic relationships of angiotensin II-like immunoreactive neurons in the rat area postrema

The ultrastructure and synaptic relationships of the angiotensin II-containing neurons in the area postrema of the rat were studied by immunocytochemistry using the avidin-biotin-complex-DAB method, and also using silver-gold intensification following the DAB reaction. At the light microscopic level, the angiotensin II-like immunoreactive neurons were observed within the area postrema, especially in the upper region. At the electron microscopic level, the angiotensin II-like immunoreactive cell bodies were observed as having a round, unindented nucleus. The nuclei of these neurons were not immunostained. The angiotensin II-like immunoreactive axon terminals often contained a few dense core vesicles in addition to many small clear synaptic vesicles. Numerous axon terminals were found to make synapses on immunonegative dendrites; they were also found to make synapses on angiotensin II-like immunoreactive dendrites. Many angiotensin II-like immunoreactive dendrites received synapses from immunonegative axon terminals. Although angiotensin II-like immunoreactive cell bodies were sometimes postsynaptic to immunoreactive axon terminals, they did not receive synapses from immunonegative axon terminals. These results provide solid morphological evidence of AP endogenous angiotensin II and confirm that in spite of circulating angiotensin II, the local neurons in the AP may also play an important role in angiotensin II-induced cardiovascular regulation.