Statin use and risk of liver cancer: an update meta-analysis

OBJECTIVE

Statins are commonly prescribed cholesterol-lowering drugs. Preclinical studies suggest that statins may possess cancer preventive properties. The primary objective of this meta-analysis was to determine the association between statin use and risk of liver cancer.

DESIGN

Meta-analysis.

SETTING

International.

PARTICIPANTS

A comprehensive literature search of PubMed, BIOSIS Previews, Web of Science, EMBASE, EBSCO and Cochrane Library was conducted through March 2014. The effect estimate was reported as pooled relative risk (RR) with 95% CIs, using the random-effects model.

RESULTS

A total of 12 studies (1 individual patient data analysis of 22 randomised controlled trials, 5 cohorts and 6 case-controls) were qualified for this meta-analysis, involving 5,640,313 participants including 35,756 liver cancer cases. Our results indicated a significant risk reduction of liver cancer among all statin users (RR=0.58, 95% CIs 0.51 to 0.67). The difference of the study designs can partly explain the significant heterogeneity found in the overall analysis (I(2)=65%, p=0.0006). No evidence of publication bias was observed in this meta-analysis. Similar risk reductions were found in the subgroups analysis of Western and Asian countries, lipophilic and hydrophilia statins. There was a trend towards more risk reductions in subgroups with higher baseline risk, inadequate adjustment and higher cumulative dosage of statin use.

CONCLUSIONS

This meta-analysis suggests that statin is associated with a significant risk reduction of liver cancer when taken daily for cardiovascular event prevention. However, this preventive effect might be overestimated due to the exposure period, the indication and contraindication of statins and other confounders. Statins might be considered as an adjuvant in the treatment of liver cancer.

Hemoporfin Photodynamic Therapy for Port-Wine Stain: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Photodynamic therapy (PDT) has shown potentially beneficial results in treating port-wine stain, but its benefit-risk profile remains undefined. This study aimed to evaluate the efficacy and safety of PDT conducted with hemoporfin and a 532 nm continuous wave laser to treat port-wine stain clinically.

PATIENTS AND METHODS

This randomized clinical trial was conducted in eight hospitals in China. Participants were adolescent and adult patients (age range: 14-65 years old) with port-wine stain. During stage 1 (day 1 to week 8) all patients were randomized at a 3:1 ratio to treatment (532 nm laser irradiation (96-120 J/cm2) with hemoporfin (5mg/kg; PDT-hemoporfin, n = 330)) or placebo groups (irradiation with placebo (PDT-placebo, n = 110)); during stage 2 (week 8 to 16) patients in both groups were offered treatment. Clinician-evaluators, who were blind to the study, classified each case on the following four-level scale according to assessment of before and after standardized pictures of the lesion area: no improvement: <20%; some improvement: 20-59%; great improvement: 60-89%; or nearly completely resolved: ≥90%. The primary efficacy endpoint was proportion of patients achieving at least some improvement at week 8. The secondary efficacy endpoints were proportion of patients achieving nearly completely resolved or at least great improvement at week 8, proportion of patients achieving early completely resolved, at least great improvement, or at least some improvement at week 16, and the corresponding satisfaction of the investigators and the patients (designated as 'excellent', 'good', 'moderate', or 'ineffective') at weeks 8 and 16.

RESULTS

Compared to the PDT-placebo group, the PDT-hemoporfin group showed a significantly higher proportion of patients that achieved at least some improvement (89.7% [n = 295; 95% CI, 85.9%-92.5%] vs. 24.5% [n = 27; 95% CI, 17.4%-33.3%]) at week 8 (P < 0.0001) and higher improvements for all secondary efficacy endpoints. Treatment reactions occurred in 99.5% (n = 731; 95% CI, 98.7%-99.8%) of the PDT-hemoporfin treatments (n = 735). Hyperpigmentation occurred in 22.9 per 100 patient-treatments (n = 168; 95% CI, 20.0-26.0) in the PDT-hemoporfin treated patients.

CONCLUSIONS

Hemoporfin-mediated PDT is an effective and safe treatment option for adolescent and adult patients with port-wine stain.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR-TRC-08000213.

VEGFR2 regulates endothelial differentiation of colon cancer cells

Background

Recent studies suggested that cancer stem-like cells contribute to tumor vasculogenesis by differentiating into endothelial cells. However, such process is governed by still undefined mechanism.

Methods

At varying differentiation levels, three representative colon cancer cells were cultured in endothelial-inducing conditioned medium: human colon cancer cells HCT116 (HCT116) (poorly differentiated), SW480 (moderately differentiated), and HT29 (well differentiated). We tested for expression of endothelial markers (cluster of differentiation (CD) 31, CD34, and vascular endothelial (VE)-cadherin and their ability to form tube-like structures in 3D culture. We also observed VEGF secretion and expressions of endothelial markers and VEGFRs in HCT116 cells under hypoxia to simulate physiological conditions. In in vitro and in xenotransplantation experiments, VE growth factor receptor 2 (VEGFR2) antagonist SKLB1002 was used to test effect of VEGFR2 in endothelial differentiation of HCT116 cells. Expression levels of VEGFR2 and VE-cadherin were assessed by immunohistochemistry of human colon cancer tissues to evaluate clinicopathological significance of VEGFR2.

Results

After culturing in endothelial-inducing conditioned medium, poorly differentiated HCT116 cells expressed endothelial markers and formed tube-like structure in vitro. HCT116 cells secreted more endogenous VEGF and expressed higher VEGFR2 under hypoxia. SKLB1002 impaired endothelial differentiation in vitro and xenotransplantation experiments, suggesting a VEGFR2-dependent mechanism. Increased expression of VEGFR2 correlated with differentiation, metastasis/recurrence, and poor prognosis in 203 human colon cancer samples. Positive correlation was observed between VEGFR2 and VE-cadherin expression.

Conclusions

VEGFR2 regulates endothelial differentiation of colon cancer cell and may be potential platform for anti-angiogenesis cancer therapy.

Endoscopic ultrasound-guided ethanol ablation therapy for tumors

Endoscopic ultrasonography (EUS) has evolved into a useful therapeutic tool for treating a broad range of tumors since being introduced into clinical practice as a diagnostic modality nearly three decades ago. In particular, EUS-guided fine-needle injection has proven a successful minimally invasive approach for treating benign lesions such as pancreatic cysts, relieving pancreatic pain through celiac plexus neurolysis, and controlling local tumor growth of unresectable malignancies by direct delivery of anti-tumor agents. One such ablative agent, ethanol, is capable of safely ablating solid or cystic lesions in hepatic tissues via percutaneous injection. Recent research and clinical interest has focused on the promise of EUS-guided ethanol ablation as a safe and effective method for treating pancreatic tumor patients with small lesions or who are poor operative candidates. Although it is not likely to replace radical resection of localized lesions or systemic treatment of metastatic tumors in all patients, EUS-guided ablation is an ideal method for patients who refuse or are not eligible for surgery. Moreover, this treatment modality may play an active role in the development of future pancreatic tumor treatments. This article reviews the most recent clinical applications of EUS-guided ethanol ablation in humans for treating pancreatic cystic tumors, pancreatic neuroendocrine tumors, and metastatic lesions.

hsa-miR-141 downregulates TM4SF1 to inhibit pancreatic cancer cell invasion and migration

Expression of the transmembrane-4-L-six-family-1 (TM4SF1) is high in human pancreatic cancer cells, but the underlying mechanism remains unclear. In this study, we aimed to identify and characterize microRNAs that regulate TM4SF1 expression in PC cells. Western blot analysis and quantitative polymerase chain reaction were used to detect TM4SF1 and hsa-miR-141 levels in four PC cell lines. SW1990 and BxPc-3 cells were transfected with the inhibitor miR-141, the inhibitor negative control, the miR-141 mimic and the mimic negative control; and cell invasion, migration, proliferation, cell cycle progression and apoptosis were detected by Transwell, MTT and flow cytometry assays, respectively. The miR-141 levels negatively correlated with the TM4SF1 protein levels in PC cells. The TM4SF1 protein levels were lower in the 141M group but higher in the 141I group, although the TM4SF1 mRNA levels had no significant changes, compared to the negative controls. Luciferase assays demonstrated that hsa-miR-141 directly targeted the 3'-untranslated region of the TM4SF1 gene. In addition, miR-141 downregulated TM4SF1 expression to inhibit invasion and migration of PC cells but had no effects on cell proliferation, cell cycle progression or apoptosis. TM4SF1 is a direct target of miR-141. Our findings that TM4SF1 expression was inhibited by miR-141 provide new insights into the oncogenic mechanism of TM4SF1 and suggest that miR-141 represents a novel molecular target for PC therapy.

Effects of low-intensity pulsed ultrasound on integrin-FAK-PI3K/Akt mechanochemical transduction in rabbit osteoarthritis chondrocytes

The effect of low-intensity pulsed ultrasound (LIPUS) on extracellular matrix (ECM) production via modulation of the integrin/focal adhesion kinase (FAK)/phosphatidylinositol 3-kinase (PI3K)/Akt pathway has been investigated in previous studies in normal chondrocytes, but not in osteoarthritis (OA). Therefore, we investigated the LIPUS-induced integrin β1/FAK/PI3K/Akt mechanochemical transduction pathway in a single study in rabbit OA chondrocytes. Normal and OA chondrocytes were exposed to LIPUS, and mRNA and protein expression of cartilage, metalloproteinases and integrin-FAK-PI3K/Akt signal pathway-related genes was determined by quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Compared with levels in normal chondrocytes, expression levels of ECM-related genes were significantly lower in OA chondrocytes and those of metalloproteinase-related genes were significantly higher. In addition, integrin β1 gene expression and the phosphorylation of FAK, PI3K and Akt were significantly higher in OA chondrocytes. The expression of all tested genes was significantly increased except for that of metalloproteinase, which was significantly decreased in the LIPUS-treated OA group compared to the untreated OA group. LIPUS may affect the integrin-FAK-PI3K/Akt mechanochemical transduction pathway and alter ECM production by OA chondrocytes. Our findings will aid the future development of a treatment or even cure for OA.

A comparative study of dual versus monoantiplatelet therapy in patients with acute large-artery atherosclerosis stroke

BACKGROUND

Antiplatelet drugs are recommended for patients with acute noncardioembolic stroke. However, few randomized clinical trials have investigated the safety and efficacy of dual antiplatelet therapy for these patients. The aim of this study was to evaluate the effects of treatment with clopidogrel and aspirin (combination therapy) and aspirin alone (monotherapy) on neurologic deterioration, platelet activation, and other short-term outcomes in patients with acute large-artery atherosclerosis stroke.

MATERIALS AND METHODS

Altogether 574 patients with acute (≤2 days) large-artery atherosclerosis stroke were randomly assigned to receive either combined clopidogrel and aspirin or aspirin alone. Platelet aggregation and platelet-leukocyte aggregation studies were performed at days 1 and 30. Primary outcomes including recurrent ischemic stroke, neurologic deterioration, periphery vascular events, and myocardial infarction were monitored. Safety endpoints were hemorrhagic episodes and death.

RESULTS

The prevalence of neurologic deterioration and recurrent ischemic stroke were lower in patients in the combination therapy group than in those of the monotherapy group (3.52% versus 9.78% and 1.76% versus 6.29%, respectively). At day 30 of treatment, the platelet aggregations and platelet-leukocyte aggregates were lower in patients who were treated with clopidogrel and aspirin than in patients given aspirin alone (P < .001).

CONCLUSIONS

For patients with acute large-artery atherosclerosis stroke, treatment with clopidogrel and aspirin for 1 month provided significantly greater inhibition of platelet activity than aspirin alone. Thus, dual therapy can be safer and more effective in reducing ischemic stroke recurrence and neurologic deterioration.

Concomitant boost IMRT-based neoadjuvant chemoradiotherapy for clinical stage II/III rectal adenocarcinoma: results of a phase II study

AIM

This study was designed to evaluate the efficacy and toxicities of concomitant boost intensity-modulated radiation therapy (IMRT) along with capecitabine and oxaliplatin, followed by a cycle of Xelox, in neoadjuvant course for locally advanced rectal cancer.

MATERIALS AND METHODS

Patients with histologically confirmed, newly diagnosed, locally advanced rectal adenocarcinoma (cT3-T4 and/or cN+) located within 12 cm of the anal verge were included in this study. Patients received IMRT to the pelvis of 50 Gy and a concomitant boost of 5 Gy to the primary tumor in 25 fractions, and concurrent with oxaliplatin (50 mg/m2 d1 weekly) and capecitabine (625 mg/m2 bid d1-5 weekly). One cycle of Xelox (oxaliplatin 130 mg/m2 on d1 and capecitabine 1000 mg/m2 twice daily d1-14) was given two weeks after the completion of chemoradiation, and radical surgery was scheduled eight weeks after chemoradiation. Tumor response was evaluated by tumor regression grade (TRG) system and acute toxicities were evaluated by NCI-CTC 3.0 criteria. Survival curves were estimated using the Kaplan-Meier method and compared with Log-rank test.

RESULTS

A total of 78 patients were included between March 2009 and May 2011 (median age 54 years; 62 male). Seventy-six patients underwent surgical resection. Twenty-eight patients underwent sphincter-sparing lower anterior resection and 18 patients (23.7%) were evaluated as pathological complete response (pCR). The incidences of grade 3 hematologic toxicity, diarrhea, and radiation dermatitis were 3.8%, 10.3%, and 17.9%, respectively. The three-year LR (local recurrence), DFS (disease-free survival) and OS (overall survival) rates were 14.6%, 63.8% and 77.4%, respectively. Initial clinical T stage and tumor regression were independent prognostic factors to DFS.

CONCLUSION

An intensified regimen of concomitant boost radiotherapy plus concurrent capecitabine and oxaliplatin, followed by one cycle of Xelox, can be safely administered in patients with locally advanced rectal cancer, and produces a high rate of pCR. A prognostic score model is helpful to distinguish different long-term prognosis groups in early stage.

Occurrence of and risk factors for diabetes mellitus in Chinese patients with chronic pancreatitis

OBJECTIVES

The aim of the study was to determine the occurrence and the risk factors of diabetes mellitus (DM) in Chinese patients with chronic pancreatitis (CP), with particular emphasis on those with endoscopic or surgical therapy for CP.

METHODS

Four hundred forty-five contacted CP patients in our hospital between January 1, 1997, and July 31, 2007, were followed up. Risk factors for DM were determined in a multivariate analysis after exclusion of 58 patients.

RESULTS

The cumulative rate of DM was 51.5% (SD, 8%) at 20 years after the onset of CP and 27.8% (SD, 6%) at 10 years after endotherapy or surgery, without significant difference between the 2 therapies (P = 0.243). The age at the onset of CP (hazard ratio, 1.032; 95% confidential interval, 1.012-1.052), smoking (2.859, 1.448-5.645), chronic pain (0.412, 0.180-0.945), and pancreatic calcifications (2.326, 1.203-4.496) were identified as independent risk factors for developing DM in the patients before any invasive therapy. Smoking (2.203, 1.153-4.209) and distal pancreatectomy (5.412, 2.506-11.690) were the independent risk factors for DM development in patients after invasive therapy.

CONCLUSIONS

The risk of DM seems to be mainly caused by progression of CP because it increased with older age, absence of chronic pain, and pancreatic calcifications, whereas this risk is influenced by smoking and distal pancreatectomy.

NF-κB RNAi decreases the Bax/Bcl-2 ratio and inhibits TNF-α-induced apoptosis in human alveolar epithelial cells

OBJECTIVE

Apoptosis of alveolar epithelial cells (AECs) plays a key role in acute lung injury (ALI). Understanding the underlying mechanism is conducive to the treatment of ALI. The goal of this study was to determine the possible involvement of nuclear factor-κB (NF-κB)/p65 and Bax/Bcl-2 in tumor necrosis factor-α (TNF-α)-induced apoptosis in AECs.

METHODS

Type II AECs, A549, with or without NF-κB/p65 expression silenced by small interfering RNA (siRNA) were challenged with TNF-α. The levels of NF-κB/p65, Bcl-2 and Bax were detected by reverse transcription-polymerase chain reaction, Western blotting, and immunocytochemical staining. The apoptosis rate was measured by flow cytometry.

RESULTS

TNF-α challenge significantly increased the transcription and translation of NF-κB/p65 and Bax genes, but significantly decreased the Bcl-2 gene level. siRNA silencing of NF-κB/p65 reversed the effect of TNF-α on NF-κB/p65, Bcl-2 and Bax, and significantly decreased the TNF-α-induced apoptosis rate of AECs, as compared to the non-silenced cells.

CONCLUSIONS

This study indicates that NF-κB plays an important role in the process of TNF-α-induced apoptosis in AECs, via regulation of the expression of Bcl-2 and Bax.

Risk factors associated with missed colorectal flat adenoma: A multicenter retrospective tandem colonoscopy study

AIM: To determine the miss rate for colorectal flat adenomas during colonoscopy and the risk factors.

METHODS: Flat adenomas are frequently missed during colonoscopy. However, the risk factors that influence their miss rates are unclear. This was a multicenter, retrospective study in which patients diagnosed with colorectal adenomas at a diagnostic colonoscopy and followed within 3 mo by a second therapeutic colonoscopy were pooled out from the established database. The “per-patient” and “per-adenoma” adenoma miss rates (AMR) for overall adenomas and flat adenomas, and patient-, adenoma-, and procedure-related risk factors potentially associated with the “per-adenoma” AMR for flat adenomas were determined.

RESULTS: Chromoscopy and high-definition colonoscopy were not taken under consideration in the study. Among 2093 patients with colorectal adenomas, 691 (33.0%) were diagnosed with flat adenomas, 514 with concomitant protruding adenomas and 177 without. The “per-patient” AMR for flat adenomas was 43.3% (299/691); the rates were 54.3% and 11.3%, respectively, for those with protruding adenomas and those without (OR = 9.320, 95%CI: 5.672-15.314, χ² = 99.084, P < 0.001). The “per-adenoma” AMR for flat adenomas was 44.3% (406/916). In multivariate analysis, older age, presence of concomitant protruding adenomas, poor bowel preparation, smaller adenoma size, location at the right colon, insufficient experience of the colonoscopist, and withdrawal time < 6 min were associated with an increased “per-adenoma” AMR for flat adenomas. The AMR for flat adenomas was moderately correlated with that for overall adenomas (r = 0.516, P < 0.0001). The AMR for flat adenomas during colonoscopy was high.

CONCLUSION: Patient’s age, concomitant protruding adenomas, bowel preparation, size and location of adenomas, proficiency of the colonoscopist, and withdrawal time are factors affecting the “per-adenoma” AMR for flat adenomas.

Curcumin inhibits hypoxia inducible factor‑1α‑induced epithelial‑mesenchymal transition in HepG2 hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) accounts for the majority of liver cancers. A hypoxic microenvironment is a common feature of HCC, and is associated with malignant invasion, metastasis and epithelial-mesenchymal transition (EMT) changes. Curcumin is a botanical agent derived from the dried rhizome of Curcuma longa. Although a number of preclinical studies have shown that curcumin has anticancer properties when administered in a normoxic microenvironment, no studies have directly examined the effect of curcumin on preventing HCC invasion and metastasis under hypoxic conditions. This study aimed to determine whether curcumin has effects on the hypoxia-induced malignant biological behavior of HCC. CoCl2 was used to establish a hypoxia model in vitro. The results showed that curcumin significantly decreased hypoxia-induced hypoxia inducible factor-1α (HIF-1α) protein level in HepG2 cells. Furthermore, cell proliferation, migration and invasiveness, as well as EMT changes associated with HIF-1α accumulation generated by a hypoxic microenvironment, were eliminated by curcumin. In conclusion, these data indicate that curcumin may be a viable anticancer agent in the treatment of HCC.

Consensus on eradication of Helicobacter pylori and prevention and control of gastric cancer in China (2019, Shanghai)

BACKGROUND AND AIM

China is a country with high prevalence of Helicobacter pylori (H. pylori) infection, which in turn is closely related to the occurrence of gastric cancer. Therefore, the risks of H. pylori infection and gastric cancer are highly overlapping, and the prevention and treatment of H. pylori infection are necessary to prevent gastric cancer.

METHODS

Based on evidence-based medicine and the Delphi method, the National Clinical Medical Research Center for Digestive Disease along with the National Early Gastrointestinal Cancer Prevention and Treatment Center Alliance organized dozens of experts in the fields of digestive diseases, H. pylori research, gastric cancer surgery, epidemiology, health economics, and health management to discuss the relationship between H. pylori eradication and prevention and the treatment of gastric cancer.

RESULTS

A preliminary consensus on the relationship between H. pylori infection and gastric cancer, H. pylori eradication and gastric cancer prevention, and H. pylori screening and eradication strategy was reached. The consensus further clarified the relationship between H. pylori and gastric cancer and how to formulate future prevention and control strategies for gastric cancer.

CONCLUSIONS

This consensus could provide guidance on early detection, diagnosis, and treatment of H. pylori to reduce the occurrence of gastric cancer in China.

Clinical profile of cluster headaches in China - a clinic-based study

BACKGROUND

The clinical profile of cluster headache in Chinese patients have not been fully studied.

METHODS

The classification and clinical features of 120 consecutive patients with cluster headache (105 males, 15 females; mean age, 34.9 ± 10.5 years) visiting at International Headache Center from May 2010 to August 2012 were analyzed.

RESULTS

Patients came from 16 different regions of China. Mean age at onset of cluster headache was 26.7 ± 10.9 years. Only 13 patients (10.8%) had previously been diagnosed with cluster headache. Mean time to diagnosis from first symptoms was 8.2 ± 7.1 years (range, 0-35 years). Chronic cluster headache was observed in only 9 patients (7.5%). The most commonly reported location of cluster headache was temporal region (75.0%), followed by retro-orbital region (68.3%), forehead (32.5%), vertex (32.5%) and occipital (22.5%). Lacrimation was the most consistently reported autonomic feature (72.5%). During acute attacks, 60.0% of patients experienced nausea, and 41.7% experienced photophobia and 40.8% experienced phonophobia. In addition, 38.3% reported restless behavior and 45.8% reported that physical activity exacerbated the pain. None of patients experienced visual or other kinds of aura symptoms before cluster attacks. We found that 38.3% of patients had <1 cluster period and 35.8% for 1-2 cluster periods per year with these periods occurring less frequently during the summer than during other seasons. Cluster duration was 1-2 months in 32.5% of patients. During cluster periods, 73.3% of patients had 1-2 attacks per day, and 39.2% experienced cluster attacks ranging in duration from 1 h to less than 2 h. The duration of attacks were 1.5 (1-2.25) hours for males and 1.5 (1-3) for females respectively. The World Health Organization quality of life-8 questionnaire showed that cluster headache reduced life quality.

CONCLUSIONS

Compared to Western patients, Chinese patients showed a relatively low prevalence of chronic cluster headaches, pain sites mainly focused on areas distributed by the first division of the trigeminal nerve, a low frequency of restlessness and absent aura. These clinical features may be more common in Eastern populations, including mainland Chinese, Japanese and Taiwanese patients, than in Western patients.

Development and clinical application of deep learning model for lung nodules screening on CT images

Lung cancer screening based on low-dose CT (LDCT) has now been widely applied because of its effectiveness and ease of performance. Radiologists who evaluate a large LDCT screening images face enormous challenges, including mechanical repetition and boring work, the easy omission of small nodules, lack of consistent criteria, etc. It requires an efficient method for helping radiologists improve nodule detection accuracy with efficiency and cost-effectiveness. Many novel deep neural network-based systems have demonstrated the potential for use in the proposed technique to detect lung nodules. However, the effectiveness of clinical practice has not been fully recognized or proven. Therefore, the aim of this study to develop and assess a deep learning (DL) algorithm in identifying pulmonary nodules (PNs) on LDCT and investigate the prevalence of the PNs in China. Radiologists and algorithm performance were assessed using the FROC score, ROC-AUC, and average time consumption. Agreement between the reference standard and the DL algorithm in detecting positive nodules was assessed per-study by Bland-Altman analysis. The Lung Nodule Analysis (LUNA) public database was used as the external test. The prevalence of NCPNs was investigated as well as other detailed information regarding the number of pulmonary nodules, their location, and characteristics, as interpreted by two radiologists.

Reduced expression of PTEN and increased PTEN phosphorylation at residue Ser380 in gastric cancer tissues: a novel mechanism of PTEN inactivation

AIM

PTEN is a tumor suppressor gene in different cancers. This study was to determine the protein expression of PTEN and phosphorylation of PTEN (p-PTEN) at residue Ser380 in different histology specimens of gastric tissues.

METHODS

A total of 179tissue specimens of normal gastric mucosa, chronic gastritis, intestinal metaplasia, dysplasia, and gastric cancer were recruited for immunohistochemical analysis of PTEN and p-PTEN expression. Four gastric cancer AGS, MKN-45, MKN-28, and SGC-7901 cell lines and a non-cancerous gastric GES-1 cell line were used to detect expression of PTEN and p-PTEN protein using Western blot.

RESULTS

Expression level of PTEN protein was significantly decreased in gastric cancer tissues compared to normal gastric mucosa, chronic gastritis, intestinal metaplasia and dysplasia (P<0.05). In contrast, p-PTEN protein level was significantly increased in intestinal metaplasia, dysplasia and gastric cancer compared to normal gastric mucosa and chronic gastritis (P<0.05). However, there was no any association of PTEN and p-PTEN expression with clinicopathological characteristics from gastric cancer patients. Moreover, the ratio of p-PTEN and PTEN was higher in gastric cancer cell lines than that of the non-malignant cells.

CONCLUSIONS

This study demonstrated that aberrant expression of PTEN and p-PTEN at residue Ser380 was early event that could contribute to gastric carcinogenesis, and that PTEN phosphorylation at residue Ser380 could be a mechanism for PTEN inactivation.

Molecular epidemiology of Clostridium difficile in a tertiary hospital of China

Clostridium difficile infection (CDI) is caused by toxin-producing strains. It accounts for 20-30 % of antibiotic-associated diarrhoea and particularly accounts for 90 % of pseudomembranous colitis. The epidemiological study of C. difficile is thus important. In this study, we report the molecular epidemiology and ward distribution of C. difficile in a tertiary hospital of China. A total of 161 toxigenic strains were isolated from 1845 patients originating from different wards and the strains were characterized based on toxin profile and multilocus sequence typing. Variable isolation rates were observed in different wards and the occurrence was higher in intensive care unit and geriatric wards. Toxin gene profiling revealed that, out of the 161 isolates, 134 (83.2)% were positive for both toxin A (tcdA) and toxin B (tcdB) (A+B+) followed by toxin A-negative and B-positive (A-B+) (16.8 %) isolates. However, only three of the toxigenic strains (1.9 %) were positive for both the cdtA and cdtB genes. Based on the molecular epidemiology study, a total of 30 different sequence types (STs), including one new ST (ST-220), were distinguishable. ST-54 was the most prevalent (23.0 %), followed by ST-35 (19.3 %) and ST-37 (10.0 %). None of the isolates belonged to ST-1 (ribotype 027) or ST-11 (ribotype 078). Taken together, the toxin profile and the molecular epidemiological data showed that all the ST-37 clades were of toxin type A-B+, which accounted for 59.3 % of all type A-B+ isolates. Meanwhile the clade 1 genotype, ST-54, was widely distributed among the geriatric, infection and haematology wards. There was no outbreak of C. difficile infection during our study; however the possibility of prolonged outbreaks cannot be completely ignored.

Downregulated miR-31 level associates with poor prognosis of gastric cancer and its restoration suppresses tumor cell malignant phenotypes by inhibiting E2F2

The miRNA microarray analysis showed that miR-31 was reduced in gastric cancer. This study further assessed miR-31 expression and role of miR-31 in gastric cancer tissues and cell lines. The data showed that miR-31 expression was down-regulated in 40 cases of gastric cancer tissues compared to the adjacent normal tissues, and low expression of miR-31 was associated with poor tumor differentiation, lymph node metastasis, advanced T stage and worse overall survival of gastric cancer patients. Ectopic expression of miR-31 reduced tumor cell viability, enhanced apoptosis, arrested tumor cells at G1 transition, and reduced tumor cell migration and invasion in SGC-7901 and MGC-803 gastric cell lines in vitro. Enforced expression of miR-31 also inhibited growth of engrafted tumors in vivo. Luciferase reporter assays and western blot revealed that E2F2 is the direct target of miR-31. E2F2 expression was upregulated in gastric cancer tissues, and inversely associated with miR-31 levels, while knockdown of E2F2 expression mimicked miR-31 anti-tumor activity in gastric cancer cells, but the ectopic expression of E2F2 rescued the miR-31-mediated inhibition in gastric cell lines. Taken together, these results demonstrated that miR-31 acts as a crucial tumor suppressive activity by inhibiting E2F2s expression. Thus, miR-31 might be a candidate therapeutic target for gastric cancer patients.

miR-125a-3p and miR-483-5p promote adipogenesis via suppressing the RhoA/ROCK1/ERK1/2 pathway in multiple symmetric lipomatosis

Multiple symmetric lipomatosis (MSL) is a rare disease characterized by symmetric and abnormal distribution of subcutaneous adipose tissue (SAT); however, the etiology is largely unknown. We report here that miR-125a-3p and miR-483-5p are upregulated in the SAT of MSL patients, promoting adipogenesis through suppressing the RhoA/ROCK1/ERK1/2 pathway. TaqMan microRNA (miR) array analysis revealed that 18 miRs were upregulated in the SAT of MSL patients. Transfection of human adipose-derived mesenchymal stem cells (hADSCs) with the individual agomirs of these 18 miRs showed that miR-125a-3p and miR-483-5p significantly promoted adipogenesis. A dual-luciferase assay showed that RhoA and ERK1 were the targets of miR-125a-3p and miR-483-5p, respectively. Moreover, transfection of hADSCs with mimics of miR-125a-3p and miR-483-5p resulted in a pronounced decrease of ERK1/2 phosphorylation in the nucleus; conversely, transfection of hADSCs with inhibitors of miR-125a-3p and miR-483-5p led to a significant increase of ERK1/2 phosphorylation in the nucleus. Most importantly, we found that miR-125a-3p and miR-483-5p promoted de novo adipose tissue formation in nude mice. These results demonstrated that miR-125a-3p and miR-483-5p coordinately promoted adipogenesis through suppressing the RhoA/ROCK1/ERK1/2 pathway. Our findings may provide novel strategies for the management and treatment of MSL or obesity.

Hepatitis B viral core protein disrupts human host gene expression by binding to promoter regions

BACKGROUND

The core protein (HBc) of hepatitis B virus (HBV) has been implicated in the malignant transformation of chronically-infected hepatocytes and displays pleiotropic functions, including RNA- and DNA-binding activities. However, the mechanism by which HBc interacts with the human genome to exert effects on hepatocyte function remains unknown. This study investigated the distribution of HBc binding to promoters in the human genome and evaluated its effects on the related genes' expression.

RESULTS

Whole-genome chromatin immunoprecipitation microarray (ChIP-on-chip) analysis was used to identify HBc-bound human gene promoters. Gene Ontology and pathway analyses were performed on related genes. The quantitative polymerase chain reaction assay was used to verify ChIP-on-chip results. Five novel genes were selected for luciferase reporter assay evaluation to assess the influence of HBc promoter binding. The HBc antibody immunoprecipitated approximately 3100 human gene promoters. Among these, 1993 are associated with known biological processes, and 2208 regulate genes with defined molecular functions. In total, 1286 of the related genes mediate primary metabolic processes, and 1398 encode proteins with binding activity. Sixty-four of the promoters regulate genes related to the mitogen-activated protein kinase (MAPK) pathways, and 41 regulate Wnt/beta-catenin pathway genes. The reporter gene assay indicated that HBc binding up-regulates proto-oncogene tyrosine-protein kinase (SRC), type 1 insulin-like growth factor receptor (IGF1R), and neurotrophic tyrosine kinase receptor 2 (NTRK2), and down-regulates v-Ha-ras Harvey rat sarcoma viral oncogene (HRAS).

CONCLUSION

HBc has the ability to bind a large number of human gene promoters, and can disrupt normal host gene expression. Manipulation of the transcriptional profile in HBV-infected hepatocytes may represent a key pathogenic mechanism of HBV infection.

Therapeutic properties of quercetin on monosodium urate crystal-induced inflammation in rat

Objectives

Gouty arthritis is characterized by intense, acute inflammatory reactions that occur in response to articular deposits of monosodium urate crystals. In this study we have assessed the effects of the flavonoid, quercetin, on monosodium urate crystal-induced inflammation in rats, an experimental model for gouty arthritis.

Methods

Gouty arthritis was induced by intra-articular injection of monosodium urate crystal suspension inside the ankle joint of the rat right hind limb. Circumference was assessed at 2, 4, 8, 12, 24, and 48 h after monosodium urate crystal injection. Histopathological analysis of joint synovial tissue, inflammatory mediator levels, lipid peroxidation, and antioxidant status in serum, liver and joint synovial tissue were determined in control and monosodium urate crystal-treated rats at the end of experiment.

Key findings

Quercetin treatment attenuated oedema in a dose-dependent manner and decreased histological signs of acute inflammation in the treated animals. In addition, quercetin treatment suppressed leucocyte recruitment, decreased chemokine levels, decreased levels of the lipid peroxidation end-product malondialdehyde, and increased antioxidant enzyme activity in treated rats.

Conclusions

These results indicated that quercetin exerted a strong anti-inflammatory effect that may be useful for the treatment of acute gouty arthritis.