Waardenburg syndrome type 2 with a de novo variant of the SOX10 gene: a case report.

BACKGROUND: Waardenburg syndrome type 2 (WS2) has been reported to be a rare hereditary disorder, which is distinguished by vivid blue eyes, varying degrees of hearing impairment, and abnormal pigment deposition in the skin and hair. Variants in the sex-determining region Y-box containing gene 10 (SOXl0) gene may cause congenital deafness and have been demonstrated to be important during the development of WS2. METHODS: Complete clinical data of the proband and her family members (her parents and 2 sisters) was collected and physical examinations were performed in the hospital. The laboratory examination including hemoglobin, Coomb's test, urine protein, ENA, autoimmune hepatitis-related autoantibodies and ultrasonography were all conducted. We obtained the peripheral blood samples from all the participants and performed whole exome sequencing and sanger sequencing validation. RESULTS: The present study identified a family of 5 members, and only the proband exhibited typical WS2. Beyond the characteristics of WS2, the proband also manifested absence of puberty. The proband and her younger sister manifested systemic lupus erythematosus (SLE). Whole exome sequencing revealed a de novo variant in the SOX10 gene. The variant c.175 C > T was located in exon 2 of the SOX10 gene, which is anticipated to result in early termination of protein translation. CONCLUSION: The present study is the first to report a case of both WS2 and SLE, and the present findings may provide a new insight into WS2.

Spontaneous intramuscular hemorrhage in cancer-associated dermatomyositis: a case and literature review.

BACKGROUND: Spontaneous intramuscular hemorrhage (SIH) is a rare but life-threatening complication of dermatomyositis (DM). The pathogenetic mechanism and management of intramuscular hematoma in these patients remains unclear. Here we discuss a case of recurrent hemorrhage in a patient with cancer-associated DM, and review the relevant literature for timely diagnosis and treatment. CASE PRESENTATION: A 53-year-old male patient presented with rashes, muscle weakness, and dysphagia and was diagnosed with DM. During treatment, he developed SIH of the arm and right psoas major muscle successively. MRI showed extensive edema of the right shoulder girdle muscle and muscle groups of the upper arm. During the second SIH, a CT scan showed new-onset hematoma formation in the right psoas major muscle. The detection of D-dimer, thrombin-antithrombin III complex (TAT), plasmin-α2-plasmininhibitor complex (PIC) and tissue plasminogen activator-inhibitor complex (t-PAIC) indicated predominant hyperfibrinolysis over thrombosis. Blood transfusion and supportive treatment were immediately performed, and the hematoma did not expand. However, his abdominal distension was not relieved after active treatment. Further electronic gastroscopy discovered gastric sinus ulcers, and histopathology of the biopsy confirmed signet-ring cell carcinoma. CONCLUSIONS: Although patients with cancer-associated DM have an increased risk of thrombosis, prophylactic anticoagulation therapy needs deliberate consideration. It is important to monitor the coagulation parameters dynamically during anticoagulation therapy. Especially when the level of D-dimer is high, and it is uncertain whether the patient is in a state of thrombosis or hyperfibrinolysis, the detection of TAT, PIC, t-PAIC can help to determine whether to initiate anticoagulation therapy.

Unusual presentation of systemic lupus erythematosus as hemophagocytic lymphohistiocytosis in a female patient: A case report.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare life-threatening disorder, often resulting in the immune-mediated injury of multiple organ systems, including primary HLH and secondary HLH (sHLH). Among them, sHLH results from infections, malignant, or autoimmune conditions, which have quite poor outcomes even with aggressive management and are more common in adults. CASE SUMMARY: We report a rare case of a 36-year-old female manifested with sHLH on background with systemic lupus erythematosus (SLE). During hospitalization, the patient was characterized by recurrent high-grade fever, petechiae and ecchymoses of abdominal skin, and pulmonary infection. Whole exon gene sequencing revealed decreased activity of natural killer cells. She received systematic treatment with Methylprednisolone, Etoposide, and anti-infective drugs. Intravenous immunoglobulin and plasmapheresis were applied when the condition was extremely acute and progressive. The patient recovered and did not present any relapse of the HLH for one year of follow-up. CONCLUSION: The case showed sHLH, thrombotic microvascular, and infection in the whole course of the disease, which was rarely reported by now. The treatment of the patient emphasizes that early recognition and treatment of sHLH in SLE patients was of utmost importance to improve the prognosis and survival rate of patients.

Edema of limbs as the primary symptom of gastric signet-ring cell carcinoma: A case report and literature review.

BACKGROUND: Metastatic skin cancers are relatively rare dermatological malignancies. They usually present as nodules, erythematous lesions, scar-like lesions or other lesion types. Signet-ring cell carcinoma (SRCC) is an uncommon histological type of gastric cancer that usually behaves aggressively and has a poor prognosis. Skin metastasis may be the first sign of clinically silent visceral cancer or recurrence of an internal malignancy. CASE SUMMARY: Herein we report on the case of a 55-year-old man with edema of a lower extremity as the primary symptom which progressed from local to generalized pitting edema in the year following skin involvement. Pathological evidence from gastroscopic specimens and subcutaneous tissue biopsy showed typical signet-ring cells and gland-like structures. Consistently, immunohistochemical analysis revealed positive pan-cytokeratin expression in tumor cells. A diagnosis of gastric SRCC with skin metastasis was established. Moreover, lymphoscintigraphy showed an obvious accumulation of radiotracer on the anterior and posterior sides of the right leg which indicated lymphedema. We reviewed the relevant literature on subcutaneous metastases of gastric SRCC. CONCLUSION: This rare case emphasizes the importance of physical examination as it may help elucidate the etiology of edema.

Sphingosine-1-Phosphate Protects Against the Development of Cardiac Remodeling via Sphingosine Kinase 2 and the S1PR2/ERK Pathway.

OBJECTIVE: Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure. Thus, there is an urgent need for more effective strategies to aid in cardiac protection. Our previous work found that sphingosine-1-phosphate (S1P) could ameliorate cardiac hypertrophy. In this study, we aimed to investigate whether S1P could prevent cardiac fibrosis and the associated mechanisms in cardiac remodeling. METHODS: Eight-week-old male C57BL/6 mice were randomly divided into a sham, transverse aortic constriction (TAC) or a TAC+S1P treatment group. RESULTS: We found that S1P treatment improved cardiac function in TAC mice and that the cardiac fibrosis ratio in the TAC+S1P group was significantly lower and was accompanied by a decrease in α-smooth muscle actin (α-SMA) and collagen type I (COL I) expression compared with the TAC group. We also found that one of the key S1P enzymes, sphingosine kinase 2 (SphK2), which was mainly distributed in cytoblasts, was downregulated in the cardiac remodeling case and recovered after S1P treatment in vivo and in vitro. In addition, our in vitro results showed that S1P treatment activated extracellular regulated protein kinases (ERK) phosphorylation mainly through the S1P receptor 2 (S1PR2) and spurred p-ERK transposition from the cytoplasm to cytoblast in H9c2 cells exposed to phenylephrine. CONCLUSION: These findings suggest that SphK2 and the S1PR2/ERK pathway may participate in the anti-remodeling effect of S1P on the heart. This work therefore uncovers a novel potential therapy for the prevention of cardiac remodeling.

Efficacy of plasma exchange on top of standard immunosuppressive therapy in adult autoimmune inflammatory rheumatic diseases-associated macrophage activation syndrome, a single center real-world analysis.

BACKGROUND: There is a lack of documented real-world evidence about the efficacy of current therapeutics for autoimmune inflammatory rheumatic diseases (AIIRD)-associated adult macrophage activation syndrome (MAS). OBJECTIVE: To analyze the efficacy of different treatments, especially plasma exchange (PE), in AIIRD-associated MAS. METHODS: Among 5775 patients with AIIRD in Tongji Hospital from 2014 to 2020, 62 AIIRD-associated MAS cases were collected. Unadjusted logistic regression, least absolute shrinkage and selection operator (LASSO), and inverse probability of treatment weight (IPTW) analyses were used to characterize the clinical features and potential factors related to the prognosis. Paired t-test was used to compared the changes of inflammatory indicators before and after PE treatment. RESULTS: The baseline data was defined as the data collected at the onset of MAS, and all of the 62 patients were diagnosed as AIIRD before MAS onset. The prevalance rate of MAS in AIIRD was 1.1%, and the most common types of AIIRD were systemic lupus erythematosus (45.2%) and adult-onset Still's disease (33.9%). All 62 MAS patients received glucocorticoids, 87.1% patients used at least one immunosuppressive agent, and 54.8% received PE. LASSO regression indicates a positive effect of PE on the basis of variables. After PE treatment, serum levels of multiple inflammatory cytokines were rapidly reduced, accompanied by improvements in clinical symptoms and laboratory indecies including ferritin, lactate dehydrogenase, and C-reactive protein. LASSO regression indicates that PE treatment was associated with a marked reduction of mortality (from 53.6% to 11.8%), with a hazard ratio (HR) of 0.148 (p < 0.001) after adjustment for confounding factors using IPTW analysis. CONCLUSION: With the background therapy of glucocorticoids and immunosuppressive agents, PE is an effective approach to rapidly clear inflammatory cytokines and reduce mortality of AIIRD-associated MAS. CLINICAL IMPLICATION: This study provided real-world information on the efficacy of PE in AIIRD-associated MAS.

Analysis of risk factors of interstitial lung disease and mortality rates in Chinese patients with idiopathic inflammatory myopathy.

AIM: To investigate the risk factors for interstitial lung disease (ILD) and prognosis in patients with idiopathic inflammatory myopathy (IIM). METHODS: A retrospective longitudinal study was performed in patients diagnosed with IIM between January 2012 and December 2018. RESULTS: The study cohort included 91 men and 195 women who were classified as having dermatomyositis (DM, n = 183), polymyositis (PM, n = 77), or clinical amyopathic DM (CADM, n = 26). ILD was identified in 46.5% (n = 133) of patients with IIM. The independent risk factors for ILD were age at disease onset, presence of anti-Ro-52 antibody, Gottron's papules, elevated serum immunoglobulin M levels and hypoalbuminemia. Older age at disease onset, ILD, malignancy, and increased serum aspartate aminotransferase and neutrophil-to-lymphocyte ratio (NLR) were identified as the independent predictors for mortality, whereas elevated serum albumin level was associated with a better prognosis. A total of 73 deaths (25.5%) occurred after a median follow-up time of 33 months. Infection (49.3%) was the leading cause of death. In the overall cohort, the 1-year, 5-year and cumulative survival rates were 83.2%, 74.2% and 69.4%, respectively. The receiver operating characteristic curve indicated that the optimal cut-off value of NLR for predicting death in IIM was 6.11. CONCLUSION: IIM patients have a poor prognosis with substantial mortality, especially in patients who have older age at onset, ILD, malignancy and higher NLR. Close monitoring and aggressive therapies are required in patients having poor predictive factors.

COVID-19 in patients with rheumatic disease in Hubei province, China: a multicentre retrospective observational study.

BACKGROUND: In the ongoing COVID-19 pandemic, the susceptibility of patients with rheumatic diseases to COVID-19 remains unclear. We aimed to investigate susceptibility to COVID-19 in patients with autoimmune rheumatic diseases during the ongoing COVID-19 pandemic. METHODS: We did a multicentre retrospective study of patients with autoimmune rheumatic diseases in Hubei province, the epicentre of the COVID-19 outbreak in China. Patients with rheumatic diseases were contacted through an automated telephone-based survey to investigate their susceptibility to COVID-19. Data about COVID-19 exposure or diagnosis were collected. Families with a documented history of COVID-19 exposure, as defined by having at least one family member diagnosed with COVID-19, were followed up by medical professionals to obtain detailed information, including sex, age, smoking history, past medical history, use of medications, and information related to COVID-19. FINDINGS: Between March 20 and March 30, 2020, 6228 patients with autoimmune rheumatic diseases were included in the study. The overall rate of COVID-19 in patients with an autoimmune rheumatic disease in our study population was 0·43% (27 of 6228 patients). We identified 42 families in which COVID-19 was diagnosed between Dec 20, 2019, and March 20, 2020, in either patients with a rheumatic disease or in a family member residing at the same physical address during the outbreak. Within these 42 families, COVID-19 was diagnosed in 27 (63%) of 43 patients with a rheumatic disease and in 28 (34%) of 83 of their family members with no rheumatic disease (adjusted odds ratio [OR] 2·68 [95% CI 1·14-6·27]; p=0·023). Patients with rheumatic disease who were taking hydroxychloroquine had a lower risk of COVID-19 infection than patients taking other disease-modifying anti-rheumatic drugs (OR 0·09 [95% CI 0·01-0·94]; p=0·044). Additionally, the risk of COVID-19 was increased with age (adjusted OR 1·04 [95%CI 1·01-1·06]; p=0·0081). INTERPRETATION: Patients with autoimmune rheumatic disease might be more susceptible to COVID-19 infection than the general population. FUNDING: National Natural Science Foundation of China and the Tongji Hospital Clinical Research Flagship Program.

Clinical features of rheumatic patients infected with COVID-19 in Wuhan, China.

OBJECTIVE: The clinical features of rheumatic patients with coronavirus disease 2019 (COVID-19) have not been reported. This study aimed to describe the clinical features of COVID-19 in rheumatic patients and provide information for handling this situation in clinical practice. METHODS: This is a retrospective case series study. Deidentified data, including gender, age, laboratory and radiological results, symptoms, signs, and medication history, were collected from 2326 patients diagnosed with COVID-19, including 21 cases in combination with rheumatic disease, in Tongji Hospital between 13 January and 15 March 2020. RESULTS: Length of hospital stay and mortality rate were similar between rheumatic and non-rheumatic groups, while the presence of respiratory failure was more common in rheumatic cases (38% vs 10%, p<0.001). Symptoms of fever, fatigue and diarrhoea were seen in 76%, 43% and 23% of patients, respectively. There were four rheumatic patients who experienced a flare of rheumatic disease during hospital stay, with symptoms of muscle aches, back pain, joint pain or rash. While lymphocytopaenia was seen in 57% of rheumatic patients, only one patient (5%) presented with leucopenia in rheumatic cases. Rheumatic patients presented with similar radiological features of ground-glass opacity and consolidation. Patients with pre-existing interstitial lung disease showed massive fibrous stripes and crazy-paving signs at an early stage. Five rheumatic cases used hydroxychloroquine before the diagnosis of COVID-19 and none progressed to critically ill stage. CONCLUSIONS: Respiratory failure was more common in rheumatic patients infected with COVID-19. Differential diagnosis between COVID-19 and a flare of rheumatic disease should be considered. TRIAL REGISTRATION NUMBER: ChiCTR2000030795.

Microvesicles released by apoptotic human neutrophils suppress proliferation and IL-2/IL-2 receptor expression of resting T helper cells.

Membrane-coated microvesicles (MVs) have been identified as important mediators in intercellular communication. During the process of apoptosis, dying cells dynamically release MVs. Neutrophils are the most abundant type of leukocytes in the circulation. Due to their very short lifespan, it is likely that they are the source of large amounts of apoptotic cell-derived MVs. Here, we show that MVs released by apoptotic human polymorphonuclear neutrophils (apoPMN-MVs), but not the apoptotic neutrophils themselves, selectively suppress the proliferation of CD25 (IL-2Rα)neg CD127 (IL-7Rα)pos Th cells in a dose-dependent manner. In contrast, the proliferation of total T cells is not affected by MVs. Importantly, apoPMN-MVs suppress the secretion of IL-2 as well as the expression of and signaling via the IL-2 receptor (IL-2R) by CD25neg CD127pos Th cells. Addition of IL-7 strongly reduced the suppression of T-cell proliferation by MVs and the addition of IL-2 completely abrogated the suppressive effect. Thus, apoPMN-MVs suppressed a subset of Th cells by downregulating IL-2 and IL-2R expression and signaling. This may represent an important mechanism to prevent the activation and expansion of resting T cells in the absence of sufficient cytokine stimulation, and thereby maintaining immune tolerance.

Combination Therapies of Diacerein and Febuxostat Inhibit IL-1ß Responses and Improve Clinical Symptoms in Patients With Refractory Gout.

There are several therapeutic strategies available for the treatment of an acute gout attack and the prevention of recurrent gout flares, and they include nonsteroid anti-inflammatory drugs. This prospective study was aimed at evaluating the efficiency and safety of diacerein in combination with febuxostat on urate control, global assessments of disease activity, self-monitored gouty acute flare times, inflammatory markers, and clinical symptoms associated with their life quantity in patients with refractory gout. A total of 64 patients with refractory gout were sequentially recruited and prescribed with oral febuxostat alone or febuxostat plus diacerein daily for 12 weeks. The intensity of joint pain, numbers of acute flare, disease activity and the levels of serum amyloid A, mature IL-1ß, IL-18, C-reactive protein, and urate in individual subjects were routine analyzed. In comparison with that treatment with febuxostat alone, treatment with both drugs for 12 weeks had a better therapeutic effect on reducing the values of visual analog scales, acute flares, and healthy assessment questionnaire scores in these gout patients. Furthermore, treatment with both drugs also significantly reduced the mean daily dose of etoricoxib and the levels of serum IL-1ß and serum amyloid A. There was no significant difference in the frequency of patients with adverse effect between these 2 groups of patients. In conclusion, combination of diacerein and febuxostat had better therapeutic effect on reducing acute gout flares, inflammation, and clinical symptoms in patients with refractory gout.

Human brucellosis mimicking axial spondyloarthritis: a challenge for rheumatologists when applying the 2009 ASAS criteria.

Although the development of the 2009 SpA classification criteria by Assessment of SpondyloArthritis international Society (ASAS) represents an important step towards a better definition of the early disease stage particularly in axial spondyloarthritis (axSpA), the specificity of the criteria has been criticized these days. As the commonest zoonotic infection worldwide, human brucellosis can mimic a large number of diseases, including SpA. This study was performed to determine the frequency of rheumatologic manifestations in patients with brucellosis and the chance of misdiagnosing them as having axSpA in central China. The results showed that clinical manifestations of axSpA could be observed in brucellosis. Over half of patients had back pain, and one fifth of the patients with back pain were less than 45 years old at onset and had the symptom for more than 3 months. Two young males were falsely classified as suffering from axSpA according to the ASAS criteria, and one with MRI proved sacroiliitis was once given Etanercept for treatment. Therefore, differential diagnosis including human brucellosis should always be kept in mind when applying the ASAS criteria, even in traditionally non-endemic areas.

Subcutaneous Panniculitis-like T Cell Lymphoma Mimicking Early-Onset Nodular Panniculitis.

BACKGROUND: Subcutaneous panniculitis-like T cell lymphoma is a very uncommon subtype of cutaneous T cell lymphoma. The manifestations of this rare disease are atypical at onset, and may mimic some rheumatic or dermatologic diseases, which causes the delay of diagnosis and treatment. CASE REPORT: We report a 24-year-old man suffering from intermittent fever and skin nodules on the left anterior chest wall, who was initially misdiagnosed with nodular panniculitis and finally diagnosed with subcutaneous panniculitis-like T cell lymphoma through repeat examination of biopsy of the skin nodule. Positron emission tomography revealed extracutaneous adipose tissue involvement. Subsequently, hemophagocytic syndrome occurred while under a conventional dose of glucocorticoid, but remission was induced by treatment with cyclosporine A and high doses of dexamethasone. CONCLUSIONS: In order to avoid the delay diagnosis and inappropriate treatment of subcutaneous panniculitis-like T cell lymphoma, in addition to a thorough physical examination, PET-CT and disease-specific pathologic, immunophenotypic, and T cell receptor tests of the skin biopsy should be performed. Extracutaneous involvement, especially hemophagocytic syndrome, indicated worse prognosis. Even so, cyclosporine A plus high-dose corticosteroid could be an option of treatment.

A Point-Scoring System for the Clinical Diagnosis of Sjögren's Syndrome Based on Quantified SPECT Imaging of Salivary Gland.

OBJECTIVE: To establish a point-scoring diagnostic system for Sjögren's syndrome (SS) based on quantified SPECT imaging of salivary gland, and evaluate its feasibility and performance compared with 2002 AECG criteria and 2012 ACR criteria. METHODS: 213 patients with suspected SS enrolled in this study. The related clinical data of all patients were collected. All patients were evaluated and grouped on a clinical basis and posttreatment follow-up by rheumatology specialists as the unified standard (SS group with 149 cases and nSS group with 64 cases). From SPECT imaging of salivary gland, Tmax, UImax, Ts and EFs were derived for bilateral parotid and submandibular glands, and compared between the groups. A point-scoring diagnostic system for SS was established based on the quantified SPECT imaging of salivary gland. We estimated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for the new diagnostic system, compared with 2002 AECG criteria and 2012 ACR criteria. RESULTS: When 7.0 was used as the cut-off point, the sensitivity, specificity, PPV, NPV and accuracy for the new point-scoring system in diagnosing SS were 89.93% (134/149), 93.75% (60/64), 97.10% (134/138), 80.00% (60/75) and 91.08% (194/213), respectively. The new point-scoring diagnostic system based on quantified SPECT imaging of salivary gland keeps the specificity comparatively to 2002 AECG criteria and 2012 ACR criteria, but improves the sensitivity significantly (P<0.01). CONCLUSION: The new point-scoring diagnostic system for SS based on quantified SPECT imaging of salivary gland may be superior to 2002 AECG criteria and 2012 ACR criteria, with higher sensitivity and similar specificity in the diagnosis of SS. Additionally, it also has good feasibility in the clinical settings.

Preliminary study of high mobility group box chromosomal protein 1(HMGB1) in ankylosing spondylitis patients.

OBJECTIVES: To compare the serum levels of high mobility group box chromosomal protein 1 (HMGB1) between patients with AS and healthy controls, and evaluate its association with disease activities and functional abilities; to investigate the cell surface receptors related to HMGB1 in AS patients. METHODS: The HMGB1 serum levels from71 previously untreated AS patients and 40 healthy controls were detected by ELISA method. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS), Bath Ankylosing Spondylitis Functional Index (BASFI), erythrocytesedimentationrate (ESR), and C-reactive protein (CRP) levels were assessed on these participants. The mRNA expression of HMGB1 and its relevant cell surface receptors RAGE, TLR2, TLR4, and IL-1Racp complex were analysed by RT-PCR. RESULTS: The HMGB1 serum levels from AS patients were significantly higher than those from healthy controls and remarkably positive correlated with BASDAI, ASDAS, BASFI, CRP, and ESR. ASDAS showed more correlated to HMGB1 serum levels than BASDAI. Besides, the expression of TLR2, TLR4, and IL-1Racp from PBMCs revealed significant correlations with the expression of HMGB1. CONCLUSIONS: HMGB1 might be a good laboratory index for the evaluation of disease activities and disease severity in AS patients. Further, extracellular HMGB1 play its inflammatory role mainly via the expression of cell surface receptors TLR2, TLR4 and IL-1RAcP complex.

Effects of cytochrome P450 arachidonic acid epoxygenases on the proliferation of tumor cells.

BACKGROUND AND OBJECTIVE: Cytochrome P450 (CYP) arachidonic acid epoxygenases promote cell proliferation and inhibit apoptosis in endothelial cells. This study was to investigate the effects of CYP epoxygenases on the proliferation of tumor cells and possible signaling pathways. METHODS: The effects of recombinant adeno-associated virus (rAAV) mediated cytochrome P450 2J2 (CYP2J2), cytochrome P450 F87V (CYPF87V) and anti-CYP2J2 on proliferation of Tca-8113, A549, Ncl-H446 and HepG2 cells were measured using MTT and flow cytometry. Expressions of phosphorylated epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK)1/2 and Akt before and after transfection were detected by western blot. Tca-8113 cells infected with rAAV-CYP2J2, rAAV-CYPF87V, rAAV-antiCYP2J2 and rAAV-GFP were inoculated into nude mice, to observe the effect of CYP epoxygenases on the growth of xenografts. RESULTS: Infection of Tca-8113, A549, Ncl-H446 and HepG2 cells with rAAV-CYP2J2 and rAAVCYPF87V significantly increased the proliferation of tumor cells by 1.7-, 1.4-, 1.6- and 2.2-fold, and 2.0-, 1.5-, 1.8- and 2.0-fold respectively, as compared with control cells. On the contrary, infection with rAAV-antiCYP2J2 inhibited the proliferation of the four tumor cell lines. Moreover, CYP epoxgenases remarkably enhanced phosphorylation of EGFR, ERK1/2 and Akt, and upregulated total PI3K by 2-, 2.3-, 2.4- and 1.9-fold in the four cell lines, while rAAV-antiCYP2J2 exerted an inhibition effect. Infection of CYP450 epoxygenase genes markedly increased the cell percentage in S/G(2)/M phases by 210% as compared to control Tca-8113 cells. rAAV-CYP2J2 and rAAV-CYPF87V promoted tumor growth of Tca-8113 cell xenografts in nude mice in comparison to the control and rAAV-antiCYP2J2 groups. CONCLUSION: CYP epoxygenases efficiently promote the proliferation of tumor cells, which may be related with the activation of EGFR, ERK1/2 and PI3K/Akt signaling pathways.

[Promotive effects of epoxyeicosatrienoic acids (EETs) on proliferation of tumor cells].

BACKGROUND & OBJECTIVE: Epoxyeicosatrienoic acids (EETs) are generated from arachidomic acid by cytochrome P450(CYP). Previous studies revealed very strong and selective expression of CYP expoxygenase in human cancer tissues, but almost none in adjacent normal tissues. This study was to investigate the promotive effect of EETs on proliferation of tumor cells and the possible mechanisms. METHODS: Four tumor cell lines, Tca-8113, A549, Ncl-H446 and HepG2, were treated with different concentrations of EETs (8,9-EET, 11,12-EET and 14,15-EET) for 12, 24, 48 and 72 h, respectively. Cell proliferation was measured using the MTT assay. The effect of exogenous EETs on cell cycle of Tca-8113 cells was assessed by flow cytometry. Signal transduction inhibitors of PI3K (LY294002), MAPKK (PD98059), MAPK (apigenin) and PKC (H7) were used to block EETs-induced cell proliferation. Expressions of the total protein and phosphorylated ERK1/2 and Akt were determined by Western blot. RESULTS: EETs promoted proliferation of tumor cells compared with the control and vehicle group in a dose-and time-dependent manner (P<0.01). Incubation of tumor cells with EETs markedly increased the cell number at S/G2-M phase. The percentages of Tca-8113 cells at S and G2-M phases were (49.7+/-7.5%) vs. (17.2+/-9.7%) (P<0.01) and (21.0+/-5.3%) vs. (4.9+/-7.3%), respectively(P<0.01) with and without the treatment of 11,12-EET. EETs incubation significantly enhanced phosphorylation of MARK as well as PI3K/Akt in tumor cells. LY294002, PD98059, apigenine and H7 reduced the stimulative effect of EETs on cell proliferation. CONCLUSION: EETs possess the promotive effect on proliferation of tumor cells via activation of MAPK and PI3K/Akt signal pathways.