The ubiquitinase ZFP91 promotes tumor cell survival and confers chemoresistance through FOXA1 destabilization.

The forkhead box A1 (FOXA1), one of the forkhead class of DNA-binding proteins, functions as a transcription factor and plays a vital role in cellular control of embryonic development and cancer progression. Downregulation of FOXA1 has reported in several types of cancer, which contributes to cancer cell survival and chemoresistance. However, the mechanism for FOXA1 downregulation in cancer remains unclear. Here, we report that the ubiquitination enzyme zinc finger protein 91 (ZFP91) ubiquitinates and destabilizes FOXA1, which promotes cancer cell growth. High level of ZFP91 expression correlates with low level of FOXA1 protein in human gastric cancer (GC) cell lines and patient samples. Furthermore, ZFP91 knockdown reduces FOXA1 polyubiquitination, which decreases FOXA1 turnover and enhances cellular sensitivity to chemotherapy. Taken together, our findings reveal ZFP91-FOXA1 axis plays an important role in promoting GC progression and provides us a potential therapeutic intervention in the treatment of GC.

STUB1 suppresseses tumorigenesis and chemoresistance through antagonizing YAP1 signaling.

Yes-associated protein (YAP) is a component of the canonical Hippo signaling pathway that is known to play essential roles in modulating organ size, development, and tumorigenesis. Activation or upregulation of YAP1, which contributes to cancer cell survival and chemoresistance, has been verified in different types of human cancers. However, the molecular mechanism of YAP1 upregulation in cancer is still unclear. Here we report that the E3 ubiquitin ligase STUB1 ubiquitinates and destabilizes YAP1, thereby inhibiting cancer cell survival. Low levels of STUB1 expression were correlated with increased protein levels of YAP1 in human gastric cancer cell lines and patient samples. Moreover, we revealed that STUB1 ubiquitinates YAP1 at the K280 site by K48-linked polyubiquitination, which in turn increases YAP1 turnover and promotes cellular chemosensitivity. Overall, our study establishes YAP1 ubiquitination and degradation mediated by the E3 ligase STUB1 as an important regulatory mechanism in gastric cancer, and provides a rationale for potential therapeutic interventions.

[Serum myeloperoxidase activity and serum paraoxonase-1 activity in patients with silicosis and observation subjects and their clinical significance].

OBJECTIVE: To investigate the serum myeloperoxidase (MPO) activity and serum paraoxonase-1 (PON-1) activity in patients with silicosis and observation subjects and their clinical significance. METHODS: Seventy-two patients with silicosis (stage I: 30 cases, stage II: 22 cases, stage III: 20 cases) and 37 observation subjects were selected as a case group, and 110 healthy men were selected as a control group. Serum MPO activity was measured by double-antibody sandwich enzyme-linked immunosorbent assay, and serum PON-1 activity was measured by chemical spectrophotometry. RESULTS: Serum MPO activity was significantly higher in the case group than in the control group [(102.1 ± 15.7) U/L vs. (62.4 ± 11.4) U/L, P < 0.01], but serum PON-1 activity was significantly lower in the case group than in the control group [(85.4 ± 15.7) U/ml vs. (125.4 ± 13.7) U/ml, P < 0.01]. Serum MPO activity was significantly lower in patients with stages I, II, and III silicosis than in the observation subjects [(91.3 ± 13.5) U/L, (85.7 ± 14.4) U/L, and (88.6 ± 14.5) U/L vs. (128.4 ± 16.4) U/L, P < 0.01]. Serum PON-1 activity declined as the stage of silicosis increased; serum PON-1 activity was significantly lower in the patients with stages II and III silicosis than in the observation subjects and the patients with stage I silicosis [(70.4 ± 11.4) U/ml and (67.6 ± 13.7) U/ml vs. (101.5 ± 14.0) U/ml and (89.1 ± 10.1) U/ml, P < 0.01]. CONCLUSION: Serum MPO activity and serum PON-1 activity are valuable for early diagnosis of silicosis and evaluation of patient's condition.

Clinical significance of anti-rheumatoid arthritis 33 antibody in patients with systemic lupus erythematosus.

Although anti-rheumatoid arthritis (RA) 33 antibodies have been reported to be present in various connective tissue diseases (CTDs), the clinical significance of anti-RA33 in CTDs is still obscure. This study was performed to explore the clinical significance of anti-RA33 in CTDs, especially systemic lupus erythematosus (SLE). A total of 565 patients with positive anti-nuclear antibodies who had been tested for anti-RA33 were included in this study and were further classified into RA33-positive and RA33-negative groups. The association between anti-RA33 and the clinical features of CTDs was examined. Receiver operating characteristic (ROC) analysis was performed to explore the diagnostic value of anti-RA33 in SLE and SLE-related organ involvement. The results showed that SLE was the most common disease in CTD patients positive for anti-RA33 (48.8%). Compared with the RA33-negative group, higher proportions of SLE-associated antibodies and SLE patients with a high disease activity as well as lower levels of serum complement components were observed in the RA33-positive group (all p < 0.05). Furthermore, CTD patients with positive anti-RA33 were more likely to suffer from mucocutaneous and hematological involvement as well as interstitial lung disease (all p < 0.05). ROC analysis revealed an area under the curve value of 0.634 (95% confidence interval: 0.587-0.681) for anti-RA33 in the diagnosis of SLE, with a specificity and sensitivity of 92.9% and 13.5%, respectively. Taken together, this study reveals a significant association between anti-RA33 and the clinical features of CTDs, especially SLE, indicating a potential clinical significance of anti-RA33 in the management of SLE.

Clinical Significance of Different Profiles of anti-Ro Antibodies in Connective Tissue Diseases.

Objective: Anti-Ro60 and anti-Ro52 antibodies are associated with different connective tissue diseases (CTDs). However, the clinical significance of anti-Ro antibodies is not always consistent among different global regions. The aim of this study was to investigate the clinical characteristics of patients with anti-Ro antibodies. Methods: A total of 1596 inpatients with anti-Ro antibodies were included in the study. Demographic, clinical, and serological data were compared between individuals with different profiles of anti-Ro antibodies: patients with anti-Ro52 antibodies alone, patients with anti-Ro60 antibodies alone, and patients with combined anti-Ro52 and anti-Ro60 antibodies. Results: Of the 1596 patients, 1362 (85.3%) were female, the mean age was 45.5 years, and systemic lupus erythematosus (SLE) (46.0%) and Sjogren's syndrome (SS) (19.0%) were the most common CTD diagnoses. Among the patients with anti-Ro52 antibodies alone, idiopathic inflammatory myopathy (18.8%) and SLE (17.6%) were the most common CTD diagnoses. The coexistent autoantibodies of this group were significantly lower compared with those of the other two groups, while the presence of anti-Jo1 antibodies were significantly higher compared with those of the other two groups (3.7% vs. 0.6% vs. 1.9%, p = 0.029). In addition, the patients with isolated anti-Ro52 antibodies were more likely to suffer from interstitial lung disease (35.5% vs. 11.3% vs. 13.7%, p < 10-4) and pulmonary arterial hypertension (10.1% vs. 5.3% vs. 3.6%, p = 0.001) compared with the other two groups of patients. Compared with patients with isolated anti-Ro52 or anti-Ro60 antibodies, the patients with combined anti-Ro52 and anti-Ro60 antibodies were more likely to suffer from xerophthalmia and xerostomia. Furthermore, hypocomplementemia, hyperglobulinemia, and proteinuria were particularly prevalent in patients with anti-Ro60 antibodies. Conclusion: Different profiles of anti-Ro antibodies were significantly associated with clinical phenotypic features in CTDs, indicating the potential diagnostic and prognostic value of these antibodies in clinical practice.

Relationship of adult neurogenesis with tau phosphorylation and GSK-3ß activity in subventricular zone.

Altered neurogenesis has been reported in Alzheimer disease (AD), the most common neurodegenerative disorder characterized with hyperphosphorylated tau and accumulation of ß-amyloid (Aß). Recent studies suggest that tau phosphorylation is essential for hippocampal neurogenesis, however, it is not known whether tau phosphorylation also play a role in neurogenesis of subventricular zone (SVZ), another main progenitor niche in the brain. Here, we examined the expression of phosphorylated tau (p-tau) in SVZ and analyzed the role of p-tau in adult SVZ neurogenesis. We found that the expression of p-tau increased during postnatal development and remains at a high level until adulthood, and the p-tau was colocalized with some SVZ neural precursors. However, up-regulating glycogen synthase kinase-3 (GSK-3), a crucial tau kinase, had no effect on SVZ neurogenesis in adult rat brain. The SVZ neurogenesis was also unaffected in tau knockout and human tau transgenic mice. These results suggest that tau phosphorylation and GSK-3 activation may not be essential for adult SVZ neurogenesis.

[Electroacupuncture at "Zusanli"(ST36) ameliorates tau hyperphosphorylation in pancreas and hippocampus of diabetic rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Zusanli"(ST36) on the phosphorylated tau levels in pancreas and hippocampus of type 2 diabetes mellitus (T2DM) rats，so as to explore the underlying mechanism of EA in diabetic demention rats. METHODS: Forty-eight male Sprague-Dawley rats were randomly divided into control, model and EA groups, with 16 rats in each group. The T2DM model was established by 6 weeks of high-fat, high-sugar diet as well as intrape-ritoneal injection of streptozocin (STZ) solution (35 mg/kg). After that, EA (2 Hz, 0.1 mA) was applied to unilateral "Zusanli"(ST36) for 30 min, once a day, 6 times a week for 4 weeks. The survival rate was recorded every week, and the fasting blood glucose (FBG) was detected on the 1st, 6th and 11th week. The level of serum insulin (INS) was measured by using ELISA. The morphological structure of pancreas islet was observed by H.E. staining. The expressions of phosphorylated tau at the sites of Ser 396 (pS396) and Thr 231 (pT231), total tau (Tau5), phosphorylated glycogen synthase kinase-3ß (pGSK-3ß) and total glycogen synthase kinase-3ß (GSK-3ß) in pancreas and hippocampus were detected by Western blot. The expression and distribution of pS396 and pT231 in pancreas and hippocampus were assayed with immunohistochemistry. RESULTS: Compared with the control group, the survival rate presented a significant decline, the contents of FBG and INS were obviously higher(P<0.01), and the structure of the pancreas islet appeared shrunken, obscure and disordered in the model group. Furthermore, the levels of pS396, pT231 in pancreas and hippocampus were obviously higher in the model group(P<0.01)，while the level of pGSK-3ß in pancreas and hippocampus was significantly lower in the model group(P<0.01). In comparison with the model group, the survival rate of EA group was higher. Following 4 weeks' interventions, the enhanced levels of tau phosphorylation and GSK-3ß activity in pancreas and hippocampus were partly reversed in the EA group compared to the model group(P<0.05，P<0.01). CONCLUSION: EA at ST36 can reduce the level of tau phosphorylation via regulating the activity of GSK-3ß in the pancreas and hippocampus of T2DM rats, which may be related with the effect of EA on the brain function in T2DM rats.

Case Report: Reversal of Long-Standing Refractory Diffuse Non-Scarring Alopecia Due to Systemic Lupus Erythematosus Following Treatment With Tofacitinib.

The Janus kinases (JAKs) are intracellular tyrosine kinases involved in a broad variety of inflammatory cascades participating in the pathogenesis of systemic lupus erythematosus (SLE). Diffuse non-scarring alopecia is one of the most frequent cutaneous manifestations in SLE, resulting in devastating psychosocial consequences. Although recent studies have shown promising outcomes of the JAK inhibitors in SLE treatment, the efficacy of tofacitinib in diffuse non-scarring alopecia due to SLE has never been reported. Here we present a 29-year-old SLE patient with a 10-year history of refractory severe diffuse non-scarring alopecia who experienced dramatic hair regrowth with tofacitinib. Furthermore, we have made a systematic review regarding the potential effectiveness of tofacitinib in systemic and cutaneous lupus erythematosus. To the best of our knowledge, this is the first case study depicting an SLE patient with refractory alopecia who experienced impressive hair regrowth with the JAK1/3 inhibitor tofacitinib therapy, which contributes to expanding the field of possible uses of tofacitinib in SLE patients with difficult-to-treat cutaneous involvement, including severe alopecia.

Recent Advances of Salivary Gland Biopsy in Sjögren's Syndrome.

Sjögren's syndrome (SS) is a chronic, systemic, inflammatory autoimmune disease characterized by lymphocyte proliferation and progressive damage to exocrine glands. The diagnosis of SS is challenging due to its complicated clinical manifestations and non-specific signs. Salivary gland biopsy plays an important role in the diagnosis of SS, especially with anti-Sjögren's syndrome antigen A (SSA) and anti-SSB antibody negativity. Histopathology based on biopsy has clinical significance for disease stratification and prognosis evaluation, such as risk assessment for the development of non-Hodgkin's lymphoma. Furthermore, histopathological changes of salivary gland may be implicated in evaluating the efficacy of biological agents in SS. In this review, we summarize the histopathological features of salivary gland, the mechanism of histopathological changes and their clinical significance, as well as non-invasive imaging techniques of salivary glands as a potential alternative to salivary gland biopsy in SS.

Dorsolateral medullary infarction during skin infection by Stenotrophomonas maltophilia in a patient with triple antiphospholipid antibody positivity: a case-based review.

Thrombotic events are the most frequent causes of death in patients with antiphospholipid syndrome (APS). Previous studies have reported infection to be the most important trigger of thrombosis in APS, with molecular mimicry considered to be a major mechanism. Although timely management of infections has been recommended in patients with high suspicion of infection, anti-infective therapy would not take effect in a short time due to the dilemma in determining the origins of infection, especially in patients undergoing immunosuppressive therapy. Here, we describe a 26-year-old patient with systemic lupus erythematosus with triple antiphospholipid antibody positivity who had a stroke involving her dorsolateral medulla, despite timely anti-infective treatment within the context of skin infection caused by Stenotrophomonas maltophilia. To the best of our knowledge, it is the first report about the association between Stenotrophomonas maltophilia infection and thrombotic complications in APS. Thus, solely focusing on anti-infective therapy by the current recommendation for the management of APS may be insufficient within the context of infection; early initiation of effective anticoagulation should also be suggested until the anti-infective therapy becomes effective, especially in patients with high-risk antiphospholipid antibody profiles, in whom the potential benefit would outweigh the risk of bleeding.

Essential role of tau phosphorylation in adult hippocampal neurogenesis.

An increased hippocampal neurogenesis has been observed in Alzheimer disease (AD), the most common neurodegenerative disorder characterized with accumulation of ß-amyloid (Aß) and hyperphosphorylated tau (p-tau). Studies in transgenic mouse models suggest that the amyloidosis suppresses adult neurogenesis. Although emerging evidence links tau to neurodevelopment, the direct data regarding tau phosphorylation in adult neurogenesis is missing. Here, we found that the immature neurons, identified by doublecortin (DCX) and neurogenic differentiation factor (neuroD), were only immunoreactive to p-tau but not to the non-p-tau in adult rat brain and human patients with AD, and the p-tau was coexpressed temporally and spatially with DCX and neuroD in the hippocampal dentate gyrus (DG) of the rat brains during postnatal development. A correlative increase of immature neuron markers and tau phosphorylation was induced in rat hippocampal DG by upregulating glycogen synthase kinase-3 (GSK-3), a crucial tau kinase, and the increased neurogenesis was due to an enhanced proliferation but not survival or differentiation of the newborn neurons. The hippocampal neurogenesis was severely impaired in tau knockout mice and activation of GSK-3 in these mice did not rescue the deficits. These results reveal an essential role of tau phosphorylation in adult hippocampal neurogenesis. It suggests that spatial/temporal manipulation of tau phosphorylation may be compensatory for the neuron loss in neurological disorders, including AD.

[Effect of Astragalus mongholicus on renal gene expression profile in mice with diabetic nephropathy].

OBJECTIVE: To study the effect of Astragalus mongholicus on renal gene expression profile in mice with diabetic nephropathy by cDNA microarray. METHOD: The mice with diabetic nephropathy were fed A. mongholicus and normal saline respectively. cDNA microarray was used to measure gene expression profile in renal tissue after 12 weeks, and the data were analyzed by bioinformatics. RT-PCR was performed to detect the relative levels of some genes which were randomly selected. RESULT: Eighty eight genes were found differently expressed in two chips. Among these genes, 81 genes were found differently expressed in reverse direction change, 7 genes were found differently expressed in same direction change. The genes altered were mainly related to material metabolism, immunity and inflammatory reaction, signal transduction, translation, transcription, et al. The expressions of genes tested by RT-PCR were in accordance with those detected by cDNA microarray. CONCLUSION: A. mongholicus may play protective roles in diabetic nephropathy through multiple pathways at gene level. The effect of A. mongholicus in genes related to material metabolism is more significant.

Dehydroevodiamine attenuates tau hyperphosphorylation and spatial memory deficit induced by activation of glycogen synthase kinase-3 in rats.

Tau hyperphosphorylation and memory deficit are characteristic alterations of Alzheimer's disease (AD), and glycogen synthase kinase-3 (GSK-3) plays a crucial role in these AD-like changes. We have reported that activation of GSK-3 through ventricular injection of wortmannin and GF-109203X (WT/GFX, 100 microM each) induces tau hyperphosphorylation and memory impairment of rats [Liu, S.J. et al., 2003. Overactivation of glycogen synthase kinase-3 by inhibition of phosphoinositol-3 kinase and protein kinase C leads to hyperphosphorylation of tau and impairment of spatial memory. J. Neurochem. 87, 1333-1344]. By using this model, we explored in the present study the effects of dehydroevodiamine (DHED), a quinazoline alkaloid isolated from Evodia rutaecarpa Bentham, on the memory retention, tau phosphorylation and the activity of GSK-3. We found that pre-administration of DHED through vena caudalis for 1 week efficiently improved the WT/GFX-induced spatial memory retention impairment of the rats; it also antagonized tau hyperphosphorylation at multiple AD sites and arrested the overactivation of GSK-3 induced by WT/GFX. Our study gave the first in vivo evidence that DHED could suppress the overactivation of GSK-3 and improve tau hyperphosphorylation and spatial memory deficit of the rats, suggesting that this chemical may be served as a candidate for arresting AD-like pathological and behavioral alterations.

Puerarin Ameliorates D-Galactose Induced Enhanced Hippocampal Neurogenesis and Tau Hyperphosphorylation in Rat Brain.

Enhanced neurogenesis has been reported in the hippocampus of patients with Alzheimer's disease (AD), the most common neurodegenerative disorder characterized with amyloid-ß (Aß) aggregation, tau hyperphosphorylation, and progressive neuronal loss. Previously we reported that tau phosphorylation played an essential role in adult hippocampal neurogenesis, and activation of glycogen synthase kinase (GSK-3), a crucial tau kinase, could induce increased hippocampal neurogenesis. In the present study, we found that treatment of D-galactose rats with Puerarin could significantly improve behavioral performance and ameliorate the enhanced neurogenesis and microtubule-associated protein tau hyperphosphorylation in the hippocampus of D-galactose rat brains. FGF-2/GSK-3 signaling pathway might be involved in the effects of Puerarin on hippocampal neurogenesis and tau hyperphosphorylation. Our finding provides primary in vivo evidence that Puerarin can attenuate AD-like enhanced hippocampal neurogenesis and tau hyperphosphorylation. Our finding also suggests Puerarin can be served as a treatment for age-related neurodegenerative disorders, such as AD.

Disease-modified glycogen synthase kinase-3ß intervention by melatonin arrests the pathology and memory deficits in an Alzheimer's animal model.

The current therapies for Alzheimer's disease (AD) are merely palliative that cannot arrest the pathologic progression of the disease. Therefore, it is critical to develop treatments that can target the disease-modifying molecule(s). In the present study, we found that treatment of tg2576 mice with melatonin from 4-8 months of age did not improve the pathology or behavioral performance of the mice. However, remarkable attenuation of tau and ß-amyloid pathologies with memory improvement were observed when melatonin was supplied from the age of 8-12 months or 4-12 months of the mice; more importantly, the improvements were still significant when the mice survived to old age. We also found that the disease stage-specific alteration of glycogen synthase kinase-3ß (GSK-3ß) but not protein phosphatase-2A, was correlated with the alterations of the pathology and behavior, and the timely targeting of GSK-3ß was critical for the efficacy of melatonin. Our finding suggests that melatonin treatment only at proper timing could arrest AD by targeting the activated GSK-3ß, which provides primary evidence for the importance and strategy in developing disease-modifying interventions of AD.

Electrocatalytic response of poly(cobalt tetraaminophthalocyanine)/multi-walled carbon nanotubes-Nafion modified electrode toward sulfadiazine in urine.

A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(Co(II)TAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs-Nafion) modified electrode is described. This electrode showed a very attractive performance by combining the advantages of Co(II)TAPc, MWCNTs, and Nafion. Compared with the bare glassy carbon electrode (GCE) and the MWCNTs-Nafion modified electrode, the electrocatalytic activity of poly(Co(II)TAPc)-coated MWCNTs-Nafion GCE generated greatly improved electrochemical detections toward sulfadiazine including low oxidation potential, high current responses, and good anti-fouling performance. The oxidation peak currents of sulfadiazine obtained on the new modified electrode increased linearly while increasing the concentration of sulfadiazine from 0.5 to 43.5 µmol/L with the detection limit of 0.17 µmol/L.

Dehydroevodiamine attenuates calyculin A-induced tau hyperphosphorylation in rat brain slices.

AIM: This study was to investigate the effect of dehydroevodiamine (DHED) on Alzheimer's disease (AD)-like tau hyperphosphorylation induced by calyculin A (CA), an inhibitor of protein phosphatase (PP)-2A and PP-1, and the involvement of PP-2A in metabolically competent rat brain slices. METHODS: Rat brain slices were pre-incubated at 33 degree centigrade in the presence (10, 100, and 200 micromol/L, respectively) or absence of DHED for 1 h. Then, CA 0.1 micromol/L was added and the slices were treated for another 2 h. Western blotting and/or immunohistochemistry were used to measure the phosphorylation level of tau and PP-2A. RESULTS: CA treatment could remarkably increase the immunoreactivity of pS262 and decrease the staining of Tau-1, representing tau hyperphosphorylation at Ser262 (pS262) and Ser198/ 199/202 (Tau-1, as the antibody reacts with unphosphorylated tau, therefore, decreased staining represents increased phosphorylation). Pre-incubation of the brain slices with DHED could efficiently attenuate the CA-induced tau hyperphosphorylation at the above AD-related sites. Additionally, DHED also decreased the basal phosphorylation level of tau at Ser396, although CA failed to induce tau hyperphosphorylation at this site. Furthermore, CA treatment induced an increased level of Tyr307-phosphorylated PP-2A, which represents inactivation of the phosphatase, whereas DHED arrested the elevation of the inhibitory modification of PP-2A. CONCLUSION: DHED can attenuate CA-induced tau hyperphosphorylation at multiple AD-related sites in metabolically active rat brain slices. The underlying mechanism may involve a decreased inhibitory phosphorylation of PP-2A at Tyr307.