Preoperative H. pylori Eradication Therapy Facilitates Precise Delineation in Early Gastric Cancer with Current H. pylori Infection

INTRODUCTION

Early gastric cancer with current Helicobacter pylori infection (HpC-EGC) is common, but it is still unclear whether H. pylori eradication therapy (Hp-ET) or endoscopic submucosal dissection (ESD) should be performed first. We evaluated Hp-ETs short-term effects on horizontal boundary delineations of HpC-EGC in ESD.

METHODS

Prospectively enrolled HpC-EGC patients were randomly assigned to eradication or control groups. Operation scopes of HpC-EGC lesions were delineated with marking dots at 5 mm out of the endoscopic demarcation line by an independent endoscopist, unaware of eradication status, before formal circumferential incision. As representatives, precise delineation rate, the shortest distance of all marking dots to the pathological demarcation line in all slices of one intact resected specimen (Dmin), and negative marking dot specimen rate were examined.

RESULTS

Twenty-three HpC-EGC patients (25 lesions) were allocated to eradication group and 26 patients (27 lesions) were allocated to the control group with similar eradication success rates and all were differentiated type. With improving background mucosa inflammation after Hp-ET and similar gastritis-like epithelium rates, 10 lesions (40.0%) in the eradication group were of precise delineation compared to control group with 2 lesions (7.4%) (relative risk = 5.40, 95% CI 1.31-22.28). Dmin of eradication and control groups were 4.17 ± 2.52 mm and 2.67 ± 2.30 mm (p = 0.029), accompanied by 4 (14.8%) and none (0.0%) specimens that exhibited positive marking dots (p = 0.11), respectively.

CONCLUSION

For HpC-EGC patients, administrating eradication medication before ESD is beneficial for the precise delineation of lesions and reducing the risk of positive horizontal resection margins.

A Novel Diagnostic Biomarker, PZP, for Detecting Colorectal Cancer in Type 2 Diabetes Mellitus Patients Identified by Serum-Based Mass Spectrometry

Background: Growing evidence has confirmed that populations with type 2 diabetes mellitus (T2DM) have an increasing risk of developing colorectal cancer (CRC). Thus, convenient and effective screening strategies for CRC should be developed for the T2DM population to increase the detection rate of CRC.

Methods: Twenty serum samples extracted from five healthy participants, five T2DM patients, five CRC patients and five T2DM patients with CRC (T2DM + CRC) were submitted to data-independent acquisition mass spectrometry (DIA-MS) analysis to discover unique differentially altered proteins (DAPs) for CRC in patients with T2DM. Then, the diagnostic value of pregnancy zone protein (PZP) was validated by ELISA analysis in the validated cohort.

Results: Based on DIA-MS analysis, we found eight unique proteins specific to T2DM patients with CRC. Among these proteins, four proteins showed different expression between the T2DM + CRC and T2DM groups, and PZP exhibited the largest difference. Next, the diagnostic value of serum PZP was validated by ELISA analysis with an AUC of 0.713. Moreover, the combination of PZP, CA199 and CEA exhibited encouraging diagnostic value, and the AUC reached 0.916.

Conclusion: Overall, our current research implied that PZP could be regarded as a newfound serum biomarker for CRC medical diagnosis in T2DM patients.

Acetylated HOXB9 at lysine 27 is of differential diagnostic value in patients with pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the ninth most common human malignancy and the sixth leading cause of cancer-related death in China. AcK27-HOXB9 is a newly identified HOXB9 post-transcriptional modification that can predict the outcome in lung adenocarcinoma and colon cancer well. However, the role of AcK27-HOXB9 in PDAC is unclear. The present study aims to investigate the differential diagnostic role of patients with AcK27-HOXB9 PDAC. Tissue microarrays consisting of 162 pancreatic tumor tissue samples from patients with PDAC and paired normal subjects were used to examine HOXB9 and AcK27-HOXB9 levels and localizations by immunohistochemical analysis and Western blot assay, respectively. HOXB9 was upregulated (P < 0.0001), and AcK27-HOXB9 (P =0.0023) was downregulated in patients with PDAC. HOXB9 promoted (P = 0.0115), while AcK27-HOXB9 (P = 0.0279) inhibited PDAC progression. AcK27-HOXB9 predicted favorable outcome in patients with PDAC (P = 0.0412). AcK27-HOXB9 also suppressed PDAC cell migration in a cell migration assay. The results of this study showed that HOXB9 promoted and AcK27-HOXB9 suppressed PDAC progression. The determination of ratio between HOXB9 and AcK27-HOXB9 exhibited potential diagnostic value in patients with PDAC.

HOXB13 networking with ABCG1/EZH2/Slug mediates metastasis and confers resistance to cisplatin in lung adenocarcinoma patients

Rationale: Distant metastasis and chemoresistance are the major causes of short survival after initial chemotherapy in lung adenocarcinoma patients. However, the underlying mechanisms remain elusive. Our pilot study identified high expression of the homeodomain transcription factor HOXB13 in chemoresistant lung adenocarcinomas. We aimed to investigate the role of HOXB13 in mediating lung adenocarcinoma chemoresistance.

Methods: Immunohistochemistry assays were employed to assess HOXB13 protein levels in 148 non-small cell lung cancer patients. The role of HOXB13 in lung adenocarcinoma progression and resistance to cisplatin therapy was analyzed in cells, xenografted mice, and patient-derived xenografts. Needle biopsies from 15 lung adenocarcinoma patients who were resistant to cisplatin and paclitaxel therapies were analyzed for HOXB13 and EZH2 protein levels using immunohistochemistry.

Results: High expression of HOXB13 observed in 17.8% of the lung adenocarcinoma patients in this study promoted cancer progression and predicted poor prognosis. HOXB13 upregulated an array of metastasis- and drug-resistance-related genes, including ABCG1, EZH2, and Slug, by directly binding to their promoters. Cisplatin induced HOXB13 expression in lung adenocarcinoma cells, and patient-derived xenografts and depletion of ABCG1 enhanced the sensitivity of lung adenocarcinoma cells to cisplatin therapy. Our results suggest that determining the combined expression of HOXB13 and its target genes can predict patient outcomes.

Conclusions: A cisplatin-HOXB13-ABCG1/EZH2/Slug network may account for a novel mechanism underlying cisplatin resistance and metastasis after chemotherapy. Determining the levels of HOXB13 and its target genes from needle biopsy specimens may help predict the sensitivity of lung adenocarcinoma patients to platinum-based chemotherapy and patient outcomes.

[A questionnaire survey for gout management in physicians in Beijing]

Objective: To provide helpful continued medical education (CME) for physicians and improve gout treatment, we conducted a questionnaire survey to investigate physicians' knowledge in nine districts of Beijing. Methods: A questionnaire survey including ten gout-related questions was conducted among 298 physicians in Beijing. Demographic data and previous gout CME experience were collected. Chi-square test or Student's t test, univariate analysis and logistic regression analysis were used to evaluate the relevant factors of physicians' knowledge level. Results: A total of 250 valid copies were collected including 127 from community service centers (CSC), 123 from tertiary hospitals. The correct answer rate of gout etiology, pathogenesis and attack symptoms were over 70% in both groups. 45.5% (56/123) CSC doctors and 57.4% (66/115) tertiary doctors answered right drugs to control acute gout attack (P=0.067). Only 42.3% (52/123) in CSC and 53.4% (63/118) in hospitals chose allopurinol as a urate-lowering drug (ULT), while 46.3% (57/123) and 32.2% (38/118) doctors considered colchicine as a ULT drug (P=0.084) respectively. Near half doctors considered that gout patients should take long-term ULT [40.5% (51/126) vs. 57.6%(68/118)respectively, P=0.007]. Univariate analysis showed that CME training could improve gout-related knowledge in CRC doctors. Conclusion: Most CSC doctors generally understand basic knowledge of gout, while confusion of treatment is still significant. CME especially including standard gout treatment should be performed by doctors in tertiary hospitals.

[Glycogen storage disease type Ⅰa: a rare cause of gout in adolescent and young adult patients]

Objective: To analyze the clinical features of secondary gout in glycogen storage disease type Ⅰa (GSD Ⅰa), so as to improve the awareness of this disease. Methods: The clinical features, laboratory findings, treatments and prognosis of 5 GSD Ⅰa patients with secondary gout who had been admitted to the Peking Union Medical College Hospital during 2006 to 2016 were collected and analyzed. GSD Ⅰa was confirmed by liver biopsy and genotyping. Results: Among the 5 patients (median age: 27 years), 3 were males and 2 were females. The mean age of gout onset was 17 ranging from 10 to 22 years old. The common manifestations of GSD included hepatomegaly since childhood, hypoglycemia, growth retardation, anemia, hyperlactacidemia and hyperlipidemia. All the 5 patients were complicated with gouty tophi and kidney stone. Gouty tophi and kidney stone were identified 3.8 years and 10.2 years after the first occurrence of articular symptoms, respectively. Renal damage occurred in 3 cases. All the patients underwent several therapeutic modalities including lifestyle intervention, allopurinol, and raw corn starch treatment. Conclusions: Determination of the presence of primary disease should be performed actively for young-onset gout with early occurrence of gouty tophi. GSD should be suspected if there exist clinical manifestations like hepatomegaly, recurrent hypoglycemia, growth retardation. Early management of hyperuricemia and gout in GSD patients is important to prevent complications and improve prognosis.

[The clinical characteristics, diagnosis and treatment of patients with gout in China]

Objective: To investigate the demographic characteristics, clinical features, diagnosis and treatment of patients with gout in China. Methods: Clinical data of 6 814 patients with gout from 100 hospitals in 27 provinces, municipalities or autonomous regions in China were collected and analyzed. Results: (1) The ratio of male to female in patients with gout was 14.7∶1. The mean age of onset was (48.8±15.1) years old. Mean serum urate level was (526.7±132.3) μmol/L. Patients' education background was of U-shaped distribution; (2) Hypertension was the most common comorbidity [15.8%(1 079/6 814)], then overweight or obesity [51.9%(3 536/6 814)]; (3) Alcohol and high-purine food intake were dominant triggering factors in men. The diagnosis of gout was made after onset in majority of patients with cardinal symptom arthralgia. Most patients had the disease less than 5 years, and the longer the course, the more flares in the previous year of entry; (4) Febuxostat was the mostly used urate-lowering medication. 20.7%(1 412/6 814), 10.8%(739/6 814) and 3.9%(265/6 814) of patients were followed up in 4 weeks, 12 weeks and 24 weeks after registration, and 18.9%(267/1 412), 29.1%(215/739) and 38.1%(101/265) of them reached the control target of serum urate levels, respectively. After treatment, patients' liver function was not affected, but serum creatinine levels decreased significantly. Conclusions: The proportion of gout patients who reach target serum urate level is very low. Further steps including education and survey need to be carried on.

Adherence to gout management recommendations of Chinese patients

Though efficacious and affordable treatments for gout are widely available, gout is still not well controlled in many countries of the world including China.To investigate patient adherence to gout management recommendations and potential barriers in Chinese male gout patients, a survey was carried out by telephone interview in male patients registered in the gout clinic at Peking Union Medical College Hospital. Adherence to dietary and medication recommendations was measured by a food frequency questionnaire and proportion of cumulative time adherent to chemical urate-lowering therapy (ULT), respectively. Dietary adherence was defined as consumption of alcohol, seafood and animal organs less than once per month, and reduced red meat after dietary counseling. Medication adherence was defined as ULT ≥80% of time in the past 12 months for patients with indications. Logistic regression models were used to identify patient characteristics associated with management adherence. Reasons for nonadherence were also sought by open-end questions.Dietary and medication adherence were 44.2% and 21.9%, respectively. Older age (odds ratio [OR] 7.90, 95% confidence interval [CI] 2.49-25.04 for age ≥60), higher serum uric acid (sUA) levels (OR 3.53, 95% CI 1.42-8.75 for the highest quartile), and tophi (OR 2.31, 95% CI 1.12-4.77) were associated with dietary adherence independently, while tophi (OR 14.05, 95% CI 2.67-74.08) and chronic kidney disease (OR 16.66, 95% CI 2.63-105.37) were associated with medication adherence independently. Reasons that patients reported for nonadherence to medication included remission after treatment (35.3%), concerns for potential side effects (22.7%), insufficient patient education (8.7%), and adverse events (8.2%).Patient adherence to gout management recommendations is poor in China. Older age, increased disease burden, and specific comorbidities were associated with management adherence.

Model to identify early-stage gastric cancers with deep invasion of submucosa based on endoscopy and endoscopic ultrasonography findings

BACKGROUND

Conventional endoscopy and endoscopic ultrasonography (EUS) are used to estimate the invasion depth of early-stage gastric cancers (EGCs), but estimates made by either technique are often inaccurate. We developed a model to determine the invasion depth of EGCs using conventional endoscopy and EUS findings, with pathology results as the reference.

METHODS

We performed a retrospective study of 195 patients (205 lesions) diagnosed with gastric cancers who underwent endoscopy and EUS followed by resection. Based on pathology analyses, lesions (n = 205) were assigned to categories of: mucosa invasion or minute invasion into the submucosal layer less than 500 μm from the muscularis mucosae (M-SM1) or penetration of 500 μm or more (≥SM2). The lesions were randomly assigned to derivation (138 lesions) and validation sets (67 lesions). A depth predictive model was proposed in the derivation set using multivariate logistic regression analyses. The discriminative power of this model was assessed in both sets.

RESULTS

Remarkable redness (OR 5.42; 95% CI 1.32-22.29), abrupt cutting of converging folds (OR 8.58; 95% CI 1.65-44.72), lesions location in the upper third of the stomach (OR 10.26; 95% CI 2.19-48.09), and deep invasion based on EUS findings (OR 16.53; 95% CI 4.48-61.15) significantly associated with ≥SM2 invasion. A model that incorporated these 4 variables discriminated between M-SM1 and ≥SM2 lesions with the area under the ROC curve of 0.865 in the derivation set and 0.797 in the validation set. In the derivation set, a cut-off score of 8 identified lesions as ≥SM2 with 54% sensitivity and 97% specificity. The model correctly predicted the invasion depth 89.86% of lesions; it overestimated the depth of 2.17% of lesions.

CONCLUSIONS

We developed a model to identify EGCs with invasion depth ≥SM2 based on endoscopy and EUS findings. This model might reduce overestimation of gastric tumor depth and prevent unnecessary gastrectomy.

Differential expression of Kindlin-1 and Kindlin-2 correlates with esophageal cancer progression and epidemiology

Esophageal cancer (EC) is one of the most lethal malignancies in China, but the etiology and risk factors remain unclear. The integrin-interacting proteins Kindlin-1 and Kindlin-2 are focal adhesion molecules that activate transmembrane receptor integrins and regulate tumor cell growth, invasion, and metastasis. Here, we report that Kindlin-1 and Kindlin-2 are differentially expressed among Chinese EC patients. For this, Kindlin-1 and Kindlin-2 expression was evaluated in 220 EC patients by immunohistochemistry (IHC) and found to be correlated with the EC progression, along with a variety of epidemiologic parameters, including smoking, family EC history, and EC invasion status. Moreover, data downloaded from the Oncomine database revealed that both Kindlin-1 and Kindlin-2 were upregulated in ECs compared with normal esophageal tissues; although Kindlin-1 was highly expressed in well-differentiated tumors, whereas Kindlin-2 was more prevalent in poorly differentiated tumors. Collectively, these data suggest that Kindlin-1 may inhibit, while Kindlin-2 may promote, EC progression. This study, for the first time, linked the expression of Kindlin-1 and Kindlin-2 with EC family genetic background and living habits, which may help further our understanding of the various causes of EC.

[Identification of a new pro-invasion factor in tumor microenvironment: progress in function and mechanism of extracellular ATP]

Up to 90% of all cancer related morbidity and mortality can be attributed to metastasis. In recent years the study of tumor microenvironment, its cellular and molecular components, and how they can affect neoplastic progression toward metastasis, has become a hot focus in cancer research. Accumulated evidence shows that the formation of metastasis is a multi-step sequential process, in which, the tumor cells continuously interact with the host microenvironment. Host derived factors, i.e. growth factors/inhibitors, angiogenic factors, chemokines, etc. together with different types of host cells, play important roles in the tumor progression towards metastasis. The interaction between the tumor cells and host microenvironment determines the fate of metastasis. The reveal of this interaction mechanism provides us an opportunity to find effective mode of interference and develop novel anti-metastasis drugs. In this review, we have summarized our work on a new pro-invasion factor identified in tumor microenvironment and how it affects tumor invasion and metastass. Adenosine triphosphate (ATP), the key intracellular energy currency, accumulates within the tumor microenvironment and is closely involved in cancer cell metabolism and in antitumor immunity. The established role of ATP as a growth modulator and a proinflammatory mediator endues ATP and other purines with potential players in host-tumor interaction. Our study demonstrated that extracellular ATP stimulated human cancer invasion in in vitro tests. Increased migration and invasive ability across Matrigel was observed in some human carcinoma cell lines, including the prostate, breast, colon, melanoma and lung, when stimulated with ATP or its analogues. ATP enhanced the motility of cancer cells via increasing the amount and length of lamellipodia and filopodia, which were necessary for the cell motility. Significant increase in Rac1 and Cdc42 activities was observed. Using cDNA microarray we found that the expression of a panel of invasion/metastasis-related genes was significantly changed, including the increased expression of interleukin (IL)-8 and matrix metalloproteinase-3 (MMP-3) after ATP treatment. Changes of some epithelial-mesenchymal transition (EMT)-related factors were also observed, including the increase of snail, decrease of E-cadherin and claudin-1. Multiple P2Y receptors subtypes were expressed on tumor cells, but P2Y2 and P2X7 receptors were found to be mainly responsible for the pro-invasive effect of ATP. Down-regulation of either P2Y2 or P2X7 abolished ATP effect on cancer invasion and expression of EMT/invasion-related genes. Further, we found that P2Y2 receptor trans-activated with epidermal growth factor receptor (EGFR) and co-activated extracellular regulated protein kinases (ERK1/2) signaling pathway, which was involved in regulating expression of EMT and other related genes. In nude mice experiment, the pro-invasive effect of ATP was further confirmed. In summary, our results reveal that ATP is a potential pro-invasive factor in tumor microenvironment. P2Y2/P2X7 receptors act as a mediator in the regulation of ATP-induced EMT and invasion of cancer cells. Given that tumor microenvironment is rich in ATP and other purines, we hypothesize that ATP might be a potential invasion stimulator in tumor microenvironment. Blocking ATP receptor might be a therapeutic target on cancer.

Smurf1 inhibits integrin activation by controlling Kindlin-2 ubiquitination and degradation

Integrin-mediated cellular functions require integrin activation by the proteins Kindlin-2 and Talin. Wei et al. show that the E3 ligase Smurf1 permits precise modulation of integrin-mediated adhesion by interacting with and promoting Kindlin-2 ubiquitination and degradation.

Integrin activation is an indispensable step for various integrin-mediated biological functions. Kindlin-2 is known to coactivate integrins with Talin; however, molecules that restrict integrin activation are elusive. Here, we demonstrate that the E3 ubiquitin ligase Smurf1 controls the amount of Kindlin-2 protein in cells and hinders integrin activation. Smurf1 interacts with and promotes Kindlin-2 ubiquitination and degradation. Smurf1 selectively mediates degradation of Kindlin-2 but not Talin, leading to inhibition of αIIbβ3 integrin activation in Chinese hamster ovary cells and β1 integrin activation in fibroblasts. Enhanced activation of β1 integrin was found in Smurf1-knockout mouse embryonic fibroblasts, which correlates with an increase in Kindlin-2 protein levels. Similarly, a reciprocal relationship between Smurf1 and Kindlin-2 protein levels is found in tissues from colon cancer patients, suggesting that Smurf1 mediates Kindlin-2 degradation in vivo. Collectively, we demonstrate that Smurf1 acts as a brake for integrin activation by controlling Kindlin-2 protein levels, a new mechanism that permits precise modulation of integrin-mediated cellular functions.

Collaboration Platforms in China for Translational and Clinical Research: The Partnership Between Peking University Health Science Center and the University of Michigan Medical School

PROBLEM

Clinical and translational research is increasing in China, attracting faculty-to-faculty collaborations between U.S. and Chinese researchers. However, examples of successful institution-to-institution collaborations to facilitate this research are limited. The authors describe a partnership between Peking University Health Science Center (PUHSC) and the University of Michigan Medical School (UMMS) designed to enable faculty-initiated joint translational and clinical research projects.

APPROACH

In 2009, UMMS leadership identified PUHSC as the most appropriate institutional partner, and the Joint Institute for Translational and Clinical Research was established in 2010. Each contributed $7 million for joint research projects in areas of mutual interest. A shared governance structure, four thematic programs (pulmonary, cardiovascular, liver, and renal diseases), three joint research-enabling cores, and processes for awarding funding have been established along with methods for collaborating and mechanisms to share data and biomaterials.

OUTCOMES

As of November 2015, 52 joint faculty proposals have been submitted, and 25 have been funded. These projects have involved more than 100,000 patients in the United States and China and have generated 13 peer-reviewed publications. Pilot data have been leveraged to secure $3.3 million of U.S. extramural funding. Faculty and trainee exchanges take place regularly (including an annual symposium), and mechanisms exist to link faculty seeking collaborations. Critical determinants of success include having co-ownership at all levels with coinvestment of resources.

NEXT STEPS

Each institution is committed to continuing its support with a repeat $7 million investment. Next steps include initiating studies in new clinical areas and pursuing large clinical intervention trials.

Clinical characteristics of early- and late-onset gout: A cross-sectional observational study from a Chinese gout clinic

A retrospective cross-sectional study using data from an outpatient clinic in China was conducted to investigate the clinical features of early-onset gout patients.All patients diagnosed with gout were asked about clinical characteristics of their gout and comorbid diseases. Patients presenting with acute flares were asked about common triggers before the flare. "Early-onset" gout was defined as onset of gout before 40 years and "late-onset" as onset ≥40 years. Major joint involvement, flare frequency before presentation, the cumulative number of involved joints, proportions of tophi complications at presentation, flare triggers, as well as any metabolic, cardiovascular, cerebrovascular, and renal comorbidities, were compared between the 2 groups.A total of 778 gout patients were enrolled in this study, including 449 (57.7%) in the early-onset group and 329 (42.3%) in the late-onset group. Compared with the late-onset gout patients, the early-onset gout patients had a higher proportion of ankle/mid-foot involvement (62.8% vs 48.2%, P < 0.001), more frequent flares before presentation (11.2 ± 1.17 vs 6.97 ± 1.03 times per year, P = 0.01), higher cumulative number of involved joints (5.2 ± 0.26 vs 3.8 ± 0.26, P < 0.001), and more likely to have alcohol consumption as a flare trigger (65.2% vs 53.9%, P = 0.03); whereas early-onset gout patients had fewer metabolic, cardiovascular, cerebrovascular, or renal complications.Early- and late-onset gout patients had different clinical features. Early-onset seems to be influenced more by lifestyle, while late-onset patients have more complications because of comorbidities.

Dynamic bio-adhesion of polymer nanoparticles on MDCK epithelial cells and its impact on bio-membranes, endocytosis and paracytosis

Nowadays, concern about the use of nanotechnology for biomedical application is unprecedentedly increasing. In fact, nanosystems applied for various potential clinical uses always have to cross the primary biological barrier consisting of epithelial cells. However, little is really known currently in terms of the influence of the dynamic bio-adhesion of nanosystems on bio-membranes as well as on endocytosis and transcytosis. This was investigated here using polymer nanoparticles (PNs) and MDCK epithelial cells as the models. Firstly, the adhesion of PNs on cell membranes was found to be time-dependent with a shift of both location and dispersion pattern, from the lateral adhesion of mainly mono-dispersed PNs initially to the apical coverage of the PN aggregate later. Then, it was interesting to observe in this study that the dynamic bio-adhesion of PNs only affected their endocytosis but not their transcytosis. It was important to find that the endocytosis of PNs was not a constant process. A GM1 dependent CDE (caveolae dependent endocytosis) pathway was dominant in the preliminary stage, followed by the co-existence of a CME (clathrin-mediated endocytosis) pathway for the PN aggregate at a later stage, in accordance with the adhesion features of PNs, suggesting the modification of PN adhesion patterns on the endocytosis pathways. Next, the PN adhesion was noticed to affect the structure of cell junctions, via altering the extra- and intra-cellular calcium levels, leading to the enhanced paracellular transport of small molecules, but not favorably enough for the obviously increased passing of PNs themselves. Finally, FRAP and other techniques all demonstrated the obvious impact of PN adhesion on the membrane confirmation, independent of the adhesion location and time, which might lower the threshold for the internalization of PNs, even their aggregates. Generally, these findings confirm that the transport pathway mechanism of PNs through epithelial cells is rather dynamic, and is remarkably affected by the adhesion patterns of PNs on the cell membrane.

[Long-term outcome of patients discharged with fever of unknown origin in the Department of General Internal Medicine of Peking Union Medical College Hospital]

OBJECTIVE

To investigate the clinical characteristics and outcome of patients with undiagnosed fever of unknown origin (FUO).

METHODS

To retrospectively review the clinic data of patients discharged with FUO from the Department of General Internal Medicine, Peking Union Medical College Hospital during 2004 to 2008. Medical records and phone call follow-up data were collected until 2014.

RESULTS

Among 758 in-patients diagnosed with FUO, 70 patients still discharged with FUO were enrolled in this study, including 23 males and 47 females. There were 14 missing patients. Finally, definite diagnoses were made in 20 patients by clinical reassessments, empirical therapy or repeated biopsies, in whom 3 patients dying from underlying diseases. A total of 36 patients did not get final diagnoses, while fever was relieved in 23 patients, including 10 treated with corticosteroids or non-steroid anti-inflammatory drugs (NSAIDs) from 1 month to 12 months due to suspected connective tissue diseases. Another 3 patients still had episodic fever. Seven patients died shortly after discharge. There were 3 dying in the long-term follow-up. The overall FUO-related mortality was 18.6%. Mortality was correlated with the number of dysfunctional organs, especially cytopenia, coagulation dysfunction, bleeding events, respiratory damage and acute renal failure with OR 2.1, 9.9, 3.3 and 6.6 (P < 0.05) respectively.

CONCLUSIONS

Close follow-up, intermittent clinical reassessments, repeated biopsies will contribute to the diagnosis of patients discharged with FUO. Empirical therapy with corticosteroids, NSAIDs or anti-tubercular drugs in selected patients may be safe and effective. Mortality rates increased with impaired organs, especially the hematological, respiratory and renal systems.

PCAF-primed EZH2 acetylation regulates its stability and promotes lung adenocarcinoma progression

Enhancer of zeste homolog 2 (EZH2) is a key epigenetic regulator that catalyzes the trimethylation of H3K27 and is modulated by post-translational modifications (PTMs). However, the precise regulation of EZH2 PTMs remains elusive. We, herein, report that EZH2 is acetylated by acetyltransferase P300/CBP-associated factor (PCAF) and is deacetylated by deacetylase SIRT1. We identified that PCAF interacts with and acetylates EZH2 mainly at lysine 348 (K348). Mechanistically, K348 acetylation decreases EZH2 phosphorylation at T345 and T487 and increases EZH2 stability without disrupting the formation of polycomb repressive complex 2 (PRC2). Functionally, EZH2 K348 acetylation enhances its capacity in suppression of the target genes and promotes lung cancer cell migration and invasion. Further, elevated EZH2 K348 acetylation in lung adenocarcinoma patients predicts a poor prognosis. Our findings define a new mechanism underlying EZH2 modulation by linking EZH2 acetylation to its phosphorylation that stabilizes EZH2 and promotes lung adenocarcinoma progression.

Kindlin-2 induced by TGF-β signaling promotes pancreatic ductal adenocarcinoma progression through downregulation of transcriptional factor HOXB9

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths with no effective therapeutics. Invasion and metastasis are the major characteristics of PDAC. However, mechanisms underlying PDAC invasion and metastasis are elusive. In this report, we found that Kindlin-2 is a target protein of transforming growth factor β (TGF-β) signaling and is upregulated by TGF-β1 in PDAC cells. TGF-β1-upregulated Kindlin-2 promotes PDAC cell growth, migration and invasion, whereas Kindlin-2 upregulates transforming growth factor receptor I (TβRI), a key component of TGF-β signaling. Thereby Kindlin-2 and TGF-β signaling constitute a positive feedback loop. Mechanistically, Kindlin-2 promotes PDAC progression by downregulation of HOXB9 and E-cadherin. For clinical relevance, enhanced expression of Kindlin-2 predicts a poor overall survival for PDAC patients. Gene expression levels of Kindlin-2, TGF-β, TβRI and HOXB9 are all correlated with the overall survival of PDAC patients in an Oncomine dataset. Taken together, our findings demonstrated that TGF-β1-induced Kindlin-2 expression promotes PDAC progression by downregulation of HOXB9 and E-cadherin.

Clinical analysis of 61 systemic lupus erythematosus patients with intestinal pseudo-obstruction and/or ureterohydronephrosis: a retrospective observational study

The objective of this article is to investigate the clinical features of intestinal pseudo-obstruction (IPO) and/or ureterohydronephrosis in systemic lupus erythematosus (SLE). Sixty-one SLE patients with IPO and/or ureterohydronephrosis were analyzed retrospectively. A total of 183 cases were randomly selected as controls from 3840 SLE inpatients without IPO and ureterohydronephrosis during the same period. Patients were assigned to 1 of the 3 groups (SLE with IPO and ureterohydronephrosis, SLE with IPO, and SLE with ureterohydronephrosis). The clinical characteristics, treatments, and prognosis were compared between the 3 groups. There were 57 females and 4 males, with a mean age of 32.0 years. IPO was the initial manifestation of SLE in 49.1% of the cases, whereas ureterohydronephrosis in 32.5%. All patients were initially treated with a high-dose steroid. Thirty-one of these patients (50.8%) also received intravenous methylprednisolone pulse therapy. Two patients died of bowel perforation and lupus encephalopathy, and the other 59 patients (96.7%) achieved remission after treatment. The incidences of fever, glomerulonephritis, nervous system involvement, serositis, erythrocyte sedimentation rate elevation, hypoalbuminemia, hypocomplementemia, and anti-SSA antibody positivity were significantly higher in patients with IPO and/or ureterohydronephrosis than in the control group (without IPO and ureterohydronephrosis). Also, patients with IPO and/or ureterohydronephrosis had higher SLE Disease Activity Index scores than control patients. Compared with SLE patients with IPO, the patients with IPO and ureterohydronephrosis had a significantly higher incidence of gallbladder wall thickening, biliary tract dilatation, and serositis, whereas the patients with ureterohydronephrosis had less mucocutaneous involvement and serositis. Eight of the 47 IPO patients who initially responded well to immunotherapy relapsed; however, all responded well to retreatment with adequate immunotherapy. Of these 8 patients, 4 relapsed following poor compliance and self-discontinuation of steroid or immunosuppressant therapy. The rate of poor compliance with immunotherapy and the number of organ systems involved in patients in the recurrent IPO group were significantly higher than those in the nonrecurrent IPO group. IPO and ureterohydronephrosis are severe complications of SLE. As patients usually respond readily to early optimal steroid treatment, early diagnosis and timely initiation of glucocorticoid are important to relieve symptoms, prevent complications, and improve prognosis.

Population impact of a high cardiovascular risk management program delivered by village doctors in rural China: design and rationale of a large, cluster-randomized controlled trial

Background

The high-risk strategy has been proven effective in preventing cardiovascular disease; however, the population benefits from these interventions remain unknown. This study aims to assess, at the population level, the effects of an evidence-based high cardiovascular risk management program delivered by village doctors in rural China.

Methods

The study will employ a cluster-randomized controlled trial in which a total of 120 villages in five northern provinces of China, will be assigned to either intervention (60 villages) or control (60 villages). Village doctors in intervention villages will be trained to implement a simple evidence-based management program designed to identify, treat and follow-up as many as possible individuals at high-risk of cardiovascular disease in the village. The intervention will also include performance feedback as well as a performance-based incentive payment scheme and will last for 2 years. We will draw two different (independent) random samples, before and after the intervention, 20 men aged ≥ 50 years and 20 women aged ≥60 years from each village in each sample and a total of 9,600 participants from 2 samples to measure the study outcomes at the population level. The primary outcome will be the pre-post difference in mean systolic blood pressure, analyzed with a generalized estimating equations extension of linear regression model to account for cluster effect. Secondary outcomes will include monthly clinic visits, provision of lifestyle advice, use of antihypertensive medications and use of aspirin. Process and economic evaluations will also be conducted.

Discussion

This trial will be the first implementation trial in the world to evaluate the population impact of the high-risk strategy in prevention and control of cardiovascular disease. The results are expected to provide important information (effectiveness, cost-effectiveness, feasibility and acceptability) to guide policy making for rural China as well as other resource-limited countries.

Trial registration

The trial is registered at ClinicalTrials.gov (NCT01259700). Date of initial registration is December 13, 2010.

Kindlin-2 regulates renal tubular cell plasticity by activation of Ras and its downstream signaling

Kindlin-2 is an adaptor protein that contributes to renal tubulointerstitial fibrosis (TIF). Epithelial-to-mesenchymal transition (EMT) in tubular epithelial cells was regarded as one of the key events in TIF. To determine whether kindlin-2 is involved in the EMT process, we investigated its regulation of EMT in human kidney tubular epithelial cells (TECs) and explored the underlying mechanism. In this study, we found that overexpression of kindlin-2 suppressed epithelial marker E-cadherin and increased the expression of fibronectin and the myofibroblast marker α-smooth muscle actin (SMA). Kindlin-2 significantly activated ERK1/2 and Akt, and inhibition of ERK1/2 or Akt reversed kindlin-2-induced EMT in human kidney TECs. Mechanistically, kindlin-2 interacted with Ras and son of sevenless (Sos)-1. Furthermore, overexpression of kindlin-2 increased Ras activation through recruiting Sos-1. Treatment with a Ras inhibitor markedly repressed kindlin-2-induced ERK1/2 and Akt activation, leading to restraint of EMT. We further demonstrated that knockdown of kindlin-2 inhibited EGF-induced Ras-Sos-1 interaction, resulting in reduction of Ras activation and suppression of EMT stimulated by EGF. Importantly, we found that depletion of kindlin-2 significantly inhibited activation of ERK1/2 and Akt signaling in mice with unilateral ureteral obstruction. We conclude that kindlin-2, through activating Ras and the downstream ERK1/2 and Akt signaling pathways, plays an important role in regulating renal tubular EMT and could be a potential therapeutic target for the treatment of fibrotic kidney diseases.

Genetic polymorphisms in AURKA, BRCA1, CCNE1 and CDK2 are associated with ovarian cancer susceptibility among Chinese Han women

INTRODUCTION

Centrosome aberrations and cell-cycle deregulation have important implications for ovarian cancer development. The AURKA, BRCA1, CCNE1 and CDK2 genes play pivotal roles in centrosome duplication and cell-cycle regulation.

METHODS

Using a haplotype-based analysis, this study aimed to investigate whether genetic polymorphisms in these four genes may contribute to ovarian cancer susceptibility. A total of 22 single nucleotide polymorphisms (SNPs) in these four genes were genotyped in 287 cases of ovarian serous cystadenocarcinomas and 618 age-matched cancer-free controls from the Chinese Han population, and then haplotype blocks were reconstructed according to our genotyping data and linkage disequilibrium (LD) status of these SNPs.

RESULTS

For AURKA, we found that haplotype GA [rs6064391 (T→G)+rs911162 (G→A)] was strongly associated with decreased ovarian cancer risk (adjusted OR=0.31, 95% CI=0.15-0.63, P=0.0012). For BRCA1, we found that haplotype CGTAG was associated with decreased ovarian cancer risk (adjusted OR=0.64, 95% CI=0.41-0.98, P=0.0417). Moreover, women harboring homozygous GA/CGTAG haplotypes showed the lowest risk (OR=0.12, 95% CI=0.02-0.94, P=0.0438). In CCNE1, the SNPs rs3218035 and rs3218042 were significantly associated with increased ovarian cancer risk (rs3218035: adjusted OR=5.20, 95% CI=1.85-14.52, P=0.0017; rs3218042: adjusted OR=4.98, 95% CI=1.75-14.19, P=0.0027). For CDK2, no significant association was found.

CONCLUSIONS

This study indicates that genetic polymorphisms of AURKA, BRCA1 and CCNE1 may affect ovarian cancer susceptibility in Chinese Han women.

Kindlin 2 regulates myogenic related factor myogenin via a canonical Wnt signaling in myogenic differentiation

Kindlin 2, as an integrin-associated protein, is required for myocyte elongation and fusion. However, the association of Kindlin 2 with muscle differentiation-related signaling pathways is unknown. Here, we identified a mechanism that Kindlin 2 regulates myogenic regulatory factors myogenin via a canonical Wnt/β-catenin signaling. We found that knockdown of Kindlin 2 leads to the abolishment of β-catenin/TCF4-mediated transcription in C2C12 cells, followed by the impairment of myogenic differentiation. Mechanistically, nuclear translocation of both Kindlin 2 and β-catenin is induced during myogenic differentiation. In particular, Kindlin 2 forms a tripartite complex with active β-catenin and TCF4, and hence co-occupied on the promoter of myogenin to enhance its expression. Functionally, depletion of Kindlin 2 impairs myogenic differentiation via downregulation of myogenin. Taken together, our data reveal that Kindlin 2 is required for Wnt signaling-regulated myogenic differentiation, providing a mechanistic insight into the role of Kindlin-2 in muscle development.

1B50-1, a mAb raised against recurrent tumor cells, targets liver tumor-initiating cells by binding to the calcium channel α2δ1 subunit

The identification and targeted therapy of cells involved in hepatocellular carcinoma (HCC) recurrence remain challenging. Here, we generated a monoclonal antibody against recurrent HCC, 1B50-1, that bound the isoform 5 of the α2δ1 subunit of voltage-gated calcium channels and identified a subset of tumor-initiating cells (TICs) with stem cell-like properties. A surgical margin with cells detected by 1B50-1 predicted rapid recurrence. Furthermore, 1B50-1 had a therapeutic effect on HCC engraftments by eliminating TICs. Finally, α2δ1 knockdown reduced self-renewal and tumor formation capacities and induced apoptosis of TICs, whereas its overexpression led to enhanced sphere formation, which is regulated by calcium influx. Thus, α2δ1 is a functional liver TIC marker, and its inhibitors may serve as potential anti-HCC drugs.

Kindlin 2 promotes breast cancer invasion via epigenetic silencing of the microRNA200 gene family

Kindlin 2, as a focal adhesion protein, controls integrin activation and regulates Wnt signaling in an integrin-binding independent manner. However, the association of Kindlin 2 with cancer-related microRNAs is unknown. Here, we report that Kindlin 2 markedly downregulates the expression of miR-200 family by inducing CpG island hypermethylation. Mechanistically, Kindlin 2 forms a complex with DNMT3A in the cell nucleus and the two proteins co-occupy the promoter of miRNA-200b. Functionally, repression of miR-200b is required for Kindlin 2-induced breast cancer cell invasion and tumor formation. Our data indicate that Kindlin 2 plays a novel role in epigenetic repression of miR-200 family, a mechanism that promotes breast cancer invasion.

Quantification of alternative splicing variants of human telomerase reverse transcriptase and correlations with telomerase activity in lung cancer

Telomerase plays important roles in the development and progression of malignant tumors, and its activity is primarily determined by transcriptional regulation of human telomerase reverse transcriptase (hTERT). Several mRNA alternative splicing variants (ASVs) for hTERT have been identified, but it remains unclear whether telomerase activity is directly associated with hTERT splicing transcripts. In this study, we developed novel real-time PCR protocols using molecular beacons and applied to lung carcinoma cell lines and cancerous tissues for quantification of telomerase activity and three essential hTERT deletion transcripts respectively. The results showed that lung carcinoma cell lines consistently demonstrated telomerase activity (14.22–31.43 TPG units per 100 cells) and various hTERT alternative splicing transcripts. For 165 lung cancer cases, telomerase activity showed significant correlation with tumor differentiation (poorly->moderately->well-differentiated, P<0.01) and with histotypes (combined small cell and squamous cell carcinoma>squamous cell carcinoma>adenosquamous carcinoma>adenocarcinoma, P<0.05). Although the overall hTERT transcripts were detected in all the samples, they were not associated with telomerase activity (r = 0.092, P = 0.24). Telomerase activity was significantly correlated with the transcriptional constituent ratio of α-deletion (r = -0.267, P = 0.026), β-deletion (r = -0.693, P = 0.0001) and γ-deletion (r = –0.614, P = 0.001). The positive rate and average constituent ratio of β-deletion transcripts (92.12%, 0.23) were higher than those of α-deletion (41.82%, 0.12) or γ-deletion (16.36%, 0.18) transcripts. The combined small-cell and squamous cell carcinomas expressed less deletion transcripts, especially β-deletion, than other histotypes, which might explain their higher telomerase activity. In conclusion, the molecular beacon-based real-time PCR protocols are rapid, sensitive and specific methods to quantify telomerase activity and hTERT ASVs. Telomerase activity may serve as a reliable and effective molecular marker to assist the evaluation of histological subtype and differentiation of lung carcinomas. Further studies on hTERT deletion splicing transcripts, rather than the overall hTERT transcripts, may improve our understanding of telomerase regulation.

Kindlin 2 forms a transcriptional complex with β-catenin and TCF4 to enhance Wnt signalling

Kindlin 2, as a focal adhesion protein, controls integrin activation. However, the association of Kindlin 2 with cancer-related signalling pathways is unknown. Here we identified a new direct interaction between Kindlin 2 and the active β-catenin. Importantly, Kindlin 2 forms a tripartite complex with β-catenin and TCF4. Mechanistically, Kindlin 2 selectively strengthens the occupancy of β-catenin on the Wnt target gene Axin2 and enhances Axin2 gene expression. Functionally, the β-catenin-Axin2-Snail cascade is required for Kindlin 2-induced tumour cell invasion. Our data indicate that Kindlin 2 is a new regulator of Wnt signalling, providing a mechanistic insight into the role of Kindlin 2 in cancer progression.

Expression of cell-cycle regulatory proteins BUBR1, MAD2, Aurora A, cyclin A and cyclin E in invasive ductal breast carcinomas

Cyclin A, cyclin E, BUBR1, MAD2 and Aurora A are all cell-cycle regulatory proteins and have been proven to play crucial roles in carcinogenesis. However, their expression patterns in invasive ductal breast carcinoma (IDBC) are controversial and unclear. In this study, we examined the expression status of these candidate proteins in a set of 117 invasive ductal carcinomas, and evaluated their associations with known clinicopathological parameters and the expressions of estrogen receptor, progesterone receptor, Ki-67 and Her-2. Univariate and multivariate data analyses both displayed that positive BUBR1 expression was associated with a high Ki-67 labeling index, and negative MAD2 expression was associated with Her-2 overexpression. Positive BUBR1 expression was also associated with a high histological tumor grade in univariate analysis, but not in multivariate analysis. In addition, high Aurora A expression was weakly associated with lymph node metastasis, and cyclin A was strongly associated with the expression of cyclin E in both univariate and multivariate models. In conclusion, this study suggests that evaluation of BUBR1, MAD2 and Aurora A expression levels is likely to improve accuracy of prognostic predictions in IDBC.

Identification of tumor metastasisrelated gene TMSG-1 by mRNA differential display

To investigate genes involved in cancer metastasis, mRNA differential display was used to compare the levels of gene expression of two cancer sublines derived from prostate carcinoma cell PC-3M that had different metastatic potentials. The differentially expressed genes were confirmed by Northern blot, and sequenced. The fulllength cDNA of a tumor metastasis suppressor gene (TMSG-1) was obtained by using EST assembling and verified by RT-PCR and sequencing. The results showed that expression levels of TMSG-1 were lower in the highly metastatic cell line 1E8, compared with the nonmetastatic cell line 2B4. The difference was significant. Fulllength cDNA of TMSG-1 was about 2 kb, containing an open reading frame that encoded a protein of 230 amino acids. GenBank Blastn showed no marked homology with known genes. The functional prediction of amino acids sequence encoded by TMSG-1 gene indicated TMSG-1 protein was transmembrane protein, with 3 transmembrane domains, 3 putative protein kinase phosphorylation sites, 2 casein kinase II phosphorylation sites and 1 Nmyristoylation site. The pattern of TMSG1 expression in 6 types of human tumor tissues indicated levels of transcripts were the highest in prostate carcinoma. TMSG-1 had lower expression in metastases of lung carcinoma compared to primary lung carcinoma. Similarly the expression levels were higher in welldifferentiated colon carcinoma than that in poorly differentiated colon carcinoma. TMSG-1 could also be detected in breast, ovarian, and pancreatic carcinoma. In 9 samples of primary gastric carcinoma tissues, RT-PCR and densitometric analysis demonstrated TMSG-1 expression levels in samples with lymph node metastases had a decreased tendency, compared to those without lymph node metastases. The difference was significant by student's t test (P< 0.05). These results indicated TMSG-1 expression levels were inversely correlated with tumor metastatic potential.

[An analysis of disease spectrum of patients admitted to the General Internal Medicine Unit at Peking Union Medical College Hospital from 2004 to 2008, and the value of general internal medicine unit in comprehensive hospitals]

OBJECTIVE

To analyze the disease spectrum of patients admitted to the General Internal Medicine Unit at Peking Union Medical College Hospital, which is the first academic division of general internal medicine in the department of medicine within Chinese medical colleges and universities, and the value of general internal medicine unit in comprehensive hospitals.

METHODS

A retrospective data review of patients admitted to the General Internal Medicine Unit from 2004 to 2008 was conducted from hospital information system and partially by chart review manually. Analysis of disease spectrum was performed thereafter.

RESULTS

A total of 2593 patients were included in our study. It consisted of 1075 men and 1518 women, with an average age of 45.1 years old. Forty point three percent of these patients were from Beijing, the local city, and the remaining 59.7% were from outside of Beijing. Sixty-four point nine percent (1683/2593) of these patients did not have a clear diagnosis on admission, including 758 fever of unknown origin (FUO) cases and 925 non-FUO cases. The final diagnostic rate of the FUO cases was 89.2% [676/758, with the first three leading causes as diseases of the musculoskeletal system and connective tissue (29.8%), certain infectious and parasitic diseases (26.3%), and neoplasm (14.5%)]. The final diagnostic rate of the 928 non-FUO cases was 86.8% (803/925), with the first three leading causes as musculoskeletal system and connective tissue (24.9%), neoplasm (15.5%), and diseases of blood and blood-forming organs (11.4%). Despite most diagnoses fitting into the above categories, the array of diseases was broad with as many as 550 discharge diagnoses from 2004 to 2008.

CONCLUSIONS

During 2004 - 2008, there was a high proportion of cases that presented to the General Internal Medicine Unit at Peking Union Medical College Hospital with an unclear diagnosis, and the spectrum of diseases diagnosed was very broad. This kind of patient admitting model might not only benefit patients with no clear admission diagnosis and patients with multidisciplinary medical problems for whom it is usually difficult to be admitted by a specialty unit, but would also benefit medical students and residents by providing a good clinical medicine teaching base. These features show the value of general internal unit in comprehensive hospitals.

Detection of telomerase activity in cultured cells and tumor tissue of lung carcinoma by modified telomeric repeat amplification protocol

Telomerase activity is found in various cell types including stem cells, neoplastic cells, and immortalized cells, suggesting a close association with their proliferation capacity. The telomeric repeat amplification protocol (TRAP) has been traditionally used to detect semi-quantitatively the telomerase activity by polyacrylamide gel electrophoresis (PAGE), which is difficult to apply for large scale analysis because of laborious post-PCR manipulation and potential carryover contamination. In the present study, a specific reverse primer was designed and the TRAP protocol was adapted to either PAGE or real-time PCR assay. Using cultured cell lines, the real-time TRAP showed a dramatic improvement in the reliability and accuracy of quantitation of telomerase activity and was able to discriminate the A549 cells from hundreds-fold human embryonic lung cells. Using clinical samples of 60 lung cancers and 8 inflammatory lesions, the real-time TRAP was also superior in quantitation, high-throughput capability and standardization. Our modified real-time TRAP should be applicable for the detection of telomerase activity for the initial screening and progression monitoring of lung cancer patients. Our approach is particularly useful when only limited clinical specimen is available, such as fine needle aspiration or other cytological specimens that may contain only a small number of tumor cells.

[Over expression of hyperplasia suppressor gene inhibits the malignant phenotype of breast cancer cell]

OBJECTIVE

To investigate the effect of over expression of human hyperplasia suppressor gene (HSG) on proliferation, invasion, apoptosis and cell cycle of human breast cancer cells and to determine the relationship between HSG and Ras-dependent signaling pathway.

METHODS

Full length HSG coding sequences were cloned into plasmid pcDNA3.0. The recombinant plasmids were transfected into MDA-MB-231, a highly malignant breast cancer cell line. Vacant pcDNA3.0 was used as the control. MTT, Matrigel transwell assay and flow cytometric analysis were used to test for proliferation, invasion, cell cycle distribution and apoptosis of tumor cells after transient transfection of HSG.GST-pulldown and Western blotting assays were performed to investigate the activity of Ras protein.

RESULTS

HSG transfection inhibited proliferation of MDA-MB-231 cells, and significantly decreased the number of invading cells in Matrigel transwell assay compared with the vector/231 group (78.5 +/- 5.8 vs. 131.1 +/- 14.5) cells. FACS analyses demonstrated that compared with the vector/231 group, up-regulation of HSG promoted breast cancer cell apoptosis [(35.8 +/- 4.8)% vs. (25.6 +/- 3.5%)] and induced G(0)/G(1) phase arrest [(56.3 +/- 2.3)% vs. (50.4 +/- 1.9%)] after transfection for 18 hours. Furthermore, GST-pulldown assay showed that over-expression of HSG remarkably decreased the activity of Ras (about 65% lower than control).

CONCLUSIONS

HSG exibits multiple anticancer functions in breast cancer cells including inhibition of proliferation and in vitro invasion, G(0)/G(1) arrest and promotion of apoptosis. Besides, inhibition of Ras-dependent signaling pathway may be involved in these processes.

Extracellular ATP enhances in vitro invasion of prostate cancer cells by activating Rho GTPase and upregulating MMPs expression

We previously found that in addition to anti-proliferation function, extracellular ATP had a pro-invasion effect on prostate cancer cells, and probably serves as an important regulator of invasion in local microenvironment. However, the underlying mechanism remains unclear. In this study, we demonstrated that ATP increased the motility of prostate cancer cells, and promoted formation of lamellipodia and filopodia. We also found that ATP induced activation of Rac1 and Cdc42, and promoted expression of MMP-3 and MMP-13. These data suggest that extracellular ATP enhances the invasion of prostate cancer cells by activating Rho GTPases Rac1 and Cdc42 and upregulating MMPs expression.

P21-activated kinase 5 is overexpressed during colorectal cancer progression and regulates colorectal carcinoma cell adhesion and migration

P21-activated kinase 5 (PAK5) is the recently identified member of the group B p21-activated kinase (PAK) family which are effectors of the small GTPase Cdc42 and Rac1, known to regulate cell motility and activate cell-survival signaling pathways. However, overexpression of PAK5 has not been associated with any cancers so far. Interestingly, we found that PAK5 was overexpressed in a variety of colorectal carcinoma (CRC) cell lines in a Western-blotting examination. Therefore, in this study, we aim to examine the PAK5 expression during CRC progression and to answer if PAK5 is involved in malignant progression of CRC. By immunohistochemistry, our results showed that PAK5 expression was increased with CRC progression through the adenoma to carcinoma sequence, with the most significant increases in invasive and metastatic CRCs (p < 0.0001). Furthermore, increased PAK5 expression was also found with the development of CRC from lower Duke's grades to higher ones (p < 0.01). Moreover, PAK5 was also increased from well to poorly differentiated CRCs (p < 0.01). Using gain and loss of function experiments, we found that PAK5 reduced CRC cell adhesion but promoted their migration on collagen type I. Taken together, our study demonstrated that PAK5 expression increased significantly with malignant progression of CRC and that PAK5 might promote CRC metastasis by regulating CRC cell adhesion and migration.

[Overexpression of human tumor metastasis-related gene TMSG-1 suppresses cell proliferation and invasion of a highly metastatic prostate cancer cell line PC-3M-1E8 in vitro]

OBJECTIVE

To investigate the effects of tumor metastasis-related gene TMSG-1 overexpression on the proliferation and invasion of a highly metastatic prostate cancer cell line in vitro.

METHODS

The eukaryotic expression plasmids containing full-length TMSG-1 cDNAs were stably transfected into the highly metastatic prostate cancer cell line PC-3M-1E8. Clones highly expressing TMSG-1 were identified by RT-PCR and Western Blot analysis after G418 screening. The cell proliferation was detected by cell growth curve, MTT assay and soft agar colony formation assay. The invasive potential of tumor cells in vitro was tested by Matrigel invasion assay.

RESULTS

Three TMSG-1 overexpression clones were selected. Cell growth curve and MTT assay showed that TMSG-1 overexpression clones exhibited a strong inhibition of proliferation compared with that of the parental cells or those transfected with vector alone from the third day of culture (P <0.05). In vitro analysis also showed that the TMSG-1 transfected clones exhibited a decreased clonogenicity in soft agar compared with that of the parental cells or those transfected with vector only (P < 0.05). TMSG-1 expression significantly suppressed cell invasion in vitro of TMSG-1-transfected PC-3M-IE8 cells (P < 0.05).

CONCLUSION

The TMSG-1 protein may serve as a tumor metastasis suppressor due to inhibiting cell proliferation and invasion of the highly metastatic prostate cancer cell line PC-3M-1E8.

[Overexpression of tumor metastasis suppressor gene 1 suppresses proliferation and invasion, but enhances apoptosis of human breast cancer cells MDA-MB-231 cells]

OBJECTIVE

To investigate the effects of tumor metastasis suppressor gene 1 (TMSG-1) overexpression on the proliferation, invasion and apoptosis of breast cancer cells and to determine possible correlations of TMSG-1 and metastasis of breast cancer.

METHODS

Full-length human TMSG-1 coding sequences were cloned into plasmid pcDNA3.0-FLAG. The recombinant plasmids constructs were transfeced into MDA-MB-231, a highly malignant breast cancer cell line. Parental, vector-only stable transfectant and TMSG-1 stable transfectant clones were tested by MTT, soft agar colony formation and Boyden chamber assays. At twenty-four hours and forty-eight hours post transient transfection, double staining with Annexin-V-FITC and PI were employed to distinguish apoptotic cells from living cells by flow cytometry analysis.

RESULTS

Three TMSG-1 overexpression clones were selected. Compared with the control cells, TMSG-1 overexpression MDA-MB-231 cells showed strong inhibition of proliferation and decreased clonogenicity in soft agar (P<0.05). Transfection of TMSG-1 into MDA-MB-231 cells significantly suppressed the cell invasion ability in vitro (decreased numbers of cells trespassing the matrigel in three experiments: 72.3+/-8.1, 85.0+/-4.2, and 73.5+/-7.8) in comparison with nave cells without transfection (187.5+/-2.1) and cells transfected with the control vector (162.3+/-6.8) (P<0.01). Transient transfection of TMSG-1 into MDA-MB-231 cells could promote cell apoptosis at 24 and 48 hours after transfection (P<0.05).

CONCLUSIONS

TMSG-1 protein may have multiple functions in the regulation of proliferation, invasion and apoptosis of metastatic breast cancer cells, likely as a metastasis suppressor gene.

[P2Y purinergic receptor activated PI-3K/Akt signaling pathway in regulation of growth and invasion of prostatic cancer]

OBJECTIVE

To investigate P2Y purinergic receptor activated PI-3K/Akt signaling pathway in the regulation of growth and invasion of prostate cancer in vitro.

METHODS

Western blot was used to detect phosphorylation of Akt (a downstream target molecule of PI-3K) by P2Y receptor agonist in 1E8 cells (a highly metastatic subclone derived from PC-3 prostatic cancer cell line). Cell counts, flow cytometry, Matrigel invasion assay, wound healing assay and gelatin zymography were used to detect changes of biological behaviors of 1E8 cells after P2Y receptor activation.

RESULTS

AMP-PNP, one non-hydrolysis ATP analogue and P2Y receptor agonist, induced significant phosphorylation of Akt in a time- and dose-dependent manner in IE8 cells. LY294002, a specific inhibitor of PI-3K, effectively blocked Akt phosphorylation induced by AMP-PNP. Continuous exposure to AMP-PNP induced significant growth inhibition of 1E8 cells (inhibition rate at 50.2% at the 8th day), and this inhibition was mainly due to an arrest at S phase of the cell cycle (the S phase fraction of AMP-PNP treated cells was 22.3% higher than that of the control). Application of LY294002 did not reverse the growth inhibition effect of AMP-PNP. Matrigel invasion assay showed that AMP-PNP stimulation increased invasive ability of 1E8 cells, and this effect was effectively blocked by LY294002. No significant changes in the activation of MMP-2 and MMP-9 were detected by gelatin zymography, although wound healing assay showed 21.2% increase in cell migration after AMP-PNP treatment.

CONCLUSIONS

PI-3K/Akt signaling pathway participates in P2Y receptor-stimulated prostate cancer invasion by enhancing cell motility, rather than up-regulating MMP-2 and MMP-9 activities. PI-3K signaling pathway plays an important role in prostate cancer proliferation, but is not involved in P2Y receptor mediated growth inhibition.

The management of gout at an academic healthcare center in Beijing: a physician survey

OBJECTIVE

Gout is a less commonly diagnosed rheumatic disease in China compared with Western countries, but its prevalence appears to be climbing. It is not known how Chinese physicians diagnose and treat their patients with gout, so we evaluated physician management of gout at a major academic healthcare center in Beijing, and investigated factors associated with better decision-making.

METHODS

A 13-question anonymous survey was distributed and collected at a medical grand rounds and then at a rheumatology grand rounds at a major teaching hospital in Beijing. Physician demographic data including educational background, work experience, job titles, specialty or subspecialties, gout patient volume seen in a year, and continuing medical education (CME) in gout were also collected in the survey. Data were analyzed by multivariate regression models to identify factors associated with appropriate answers.

RESULTS

Twenty-seven residents and general internists, 26 rheumatologists and fellows, and 28 physicians and fellows of other medical subspecialties from the Department of Medicine including visiting physicians responded to the survey. Among respondents, 78% think it is important for a definitive diagnosis of gout, but few actually perform aspiration of the affected joint fluid. Eighty-four percent report that they often follow the serum urate level of their patients with diagnosed gout. When treating acute gout in otherwise healthy patients, most physicians (77%) prefer oral colchicine, and in patients with renal impairment, about half of them (48%) choose corticosteroids or corticotropin as their first treatment. For longterm urate-lowering therapy, most physicians (87%) described a variety of indications that we consider less appropriate. They (86%) tend to initiate it early (< 2 weeks) after acute flares. When urate-lowering therapy is used, 80% of physicians sustain it less than 5 years. Further, only 12% of physicians use antiinflammatory prophylaxis during the initiation of urate-lowering treatment, and only 5% maintain it for an appropriate period of time. Logistic regression analysis of physician demographic data, educational background, and work experience found no consistent independent factors associated with better decision-making, other than CME, that were associated with establishing the definite diagnosis correctly. Specifically, the number of gout patients seen by physicians was not related to better decision-making.

CONCLUSION

The physicians' reported management of gout at this major academic healthcare center in Beijing was often inconsistent with current evidence. High quality CME is required to improve Chinese physician management of gout.

[Biological implications of the inhibition of survivin by RNA interference in human androgen-independent prostate carcinoma with highly metastatic potential]

OBJECTIVE

To determine the expression level of survivin in androgen-independent prostate carcinoma, and to investigate the biological role of survivin in invasion and metastasis of androgen-independent prostate carcinoma.

METHODS

Highly metastatic prostatic cancer cell line PC-3M-1E8 was stably transfected with pSilencer plasmid targeting survivin expression by RNA interference. The biological effects were observed, including anchorage-independent growth, in vitro invasion by soft agar colony formation and Boyden chamber assay, and also in vivo tumorigenesis in nude mice. Cell cycle and apoptosis indices were evaluated by flow cytometry and Western blot analysis of bioactive fragments of caspase 3.

RESULTS

The expression of survivin in transfected PC-3M-1E8 cells was markedly depressed at both mRNA and protein levels (about 78% to 80%) as compared with control. The growth of tumor cells was retarded by anchorage-independent growth assay. The survivin transfectants formed smaller and fewer colonies (14.33 +/- 3.51) than the negative (52.33 +/- 6.81) and blank controls (54.00 +/- 6.00). Inhibition of survivin expression was correlated with enhanced apoptosis of tumor cells (percentages of apoptotic cells of the negative control, blank control and experimental groups were 5.88 +/- 0.99, 6.97 +/- 1.60, 16.40 +/- 1.95 respectively), along with an increased expression of activated caspase 3, and cell cycle inhibition at G(0)/G(1) phase (the relative number of cells at G(0)/G(1) phase were 43.65 +/- 3.44, 43.59 +/- 1.83 and 52.71 +/- 1.10, respectively). In addition, multinucleated giant cells were observed along with a marked inhibition of invasion as reflected by fewer penetrating cells by Boyden chamber assay (46.07 +/- 9.97, 47.87 +/- 9.58 and 38.67 +/- 6.59, respectively).

CONCLUSIONS

Survivin expression is high in androgen-independent prostate cancer cells and likely may be related to the apoptosis, growth and invasion of the tumor cells. Targeting the survivin pathway by RNA interference appears to be a promising approach for clinical treatment of androgen-independent prostate cancer.

[Decision-making about gout by physicians of China and influencing factors thereof]

OBJECTIVE

To investigate the decision-making about gout by physicians of China and influencing factors thereof.

METHODS

A questionnaire survey, including 13 multiple choice questions, was divided into 2 stages. The first/stage questionnaire survey was conducted among 121 physicians of the departments of internal medicine and rheumatology respectively during the grand ward rounds, and the second-stage questionnaire survey was conducted among 75 physicians attending a national continuous medical education (CME) workshop of rheumatology. The data thus collected were pooled and analyzed by logistic regression models.

RESULTS

62 effective questionnaires were collected in the first/stage survey, and 38 effective questionnaires were collected in the second-stage survey, both with a missing rate < 10%. 78.3% of the respondents considered aspiration of the joint fluid as critical for the definitive diagnosis of gout, but only 2.4% of the respondents did so frequently. When treating acute gout in otherwise healthy patients, 69.2% of the respondents preferred oral colchicine, and while treating the patients with renal dysfunction, 41.7% of the respondents used corticosteroids or corticotrophin as the first choice. For long-term uric acid-lowering therapy, 99 of them (82.5%) described a variety of incorrect indications, 107 of them (89.2%) initiated the treatment too early (< or = 2 weeks after the remission), and 92 of them (76.7%) failed to sustain the treatment for at least 5 years. Only 17 physicians (14.2%) used prophylaxis while initiating the uric acid-lowering treatment and only 7 of them (5.8%) selected a prophylaxis time of 7 approximately 12 months. Multiple logistic regression analysis showed that only CMD on gout was associated with correct diagnosis strategy (OR 7.1, 95% CI 2.1 approximately 23.7).

CONCLUSION

The management of gout by the physicians in China is often not consistent with that generally accepted internationally. High quality CME may improve the decision-making ability of physicians.

[Status and clinical implication of c-kit and PDGFRA mutations in 165 cases of gastrointestinal stromal tumor (GIST)]

OBJECTIVE

To investigate the status of c-kit and PDGFRA mutations of GIST in a the large sample of Chinese patients.

METHOD

One hundred and sixty-five cases were evaluated for the presence of c-kit and PDGFRA mutations. Exon 9, 11, 13, 17 of c-kit and exon 12, 18 of PDGFRA were analyzed by PCR amplification and direct sequencing.

RESULTS

Immunohistochemical demonstrations of KIT (CD117) were seen in 94% of the cases (155/165). Overall, c-kit mutations were identified in 76.1% (118/155) of CD117 positive cases: 67.1% (104/155) involving exon 11, 7.1% (11/155) involving exon 9, 1.3% (2/155) involving exon 13 and 0.6% (1/155) involving exon 17. The c-kit exon 11 mutations were mostly heterogeneous and clustered in the classic "hot spot" at the 5' end of the exon, including in-frame deletion and point mutation. The second "hot spots" were internal tandem duplications (ITD) at the 3' end of the exon, which were associated with female patient, older age, stomach location and low mitotic counts. The exon 9 mutations correlated with a distinct subset of GISTs involving the small bowel of young male patients. A new point mutation of L641P was identified in exon 13. PDGFRA mutations were present in 50% (5/10) of CD117-negative GISTs, all involving exon 18 with the majority of mutations being D842V. One novel in-frame deletion of IMHD mutation at codon 843 - 846 with S847T was identified. GISTs with PDGFRA mutations were often larger tumors arising from the omentum/mesentery of young male patients with high risk of aggressive behavior.

CONCLUSIONS

The vast majority of GISTs in this study harbored c-kit and PDGFRA mutations, there were non-random relations between the gene mutation patterns and the locations of GISTs. It appears that Chinese GIST patients have some unique mutation patterns. It is necessary to evaluate the gene mutations status of GISTs to guide target therapy.

[Correlation between Stat3 signal transduction pathway and expression of cyclooxygenase-2 in colorectal cancer cells]

OBJECTIVE

To explore the expression of Stat3 signal transduction pathway and expression of cyclooxygenase-2 (COX-2) in colorectal cancer cells and their correlation with the clinicopathological parameters of colorectal cancer, and to reveal the mechanism of Stat3 signal transduction pathway regulating the expression of cCOX-2 in colorectal cancer cells.

METHODS

RT-PCR was used to detect the mRNA expression of Stat3 and COX-2 and immunohistochemistry was used to detect the protein expression of Stat3 and COX-2 in 50 specimens excised during operation from 50 patients with colorectal cancer aged 58 (37-75). Human colorectal cancer cells of the HT-29 strain were cultured. MTT method was used to examine the growth of the cells. AG490, an inhibitor of the upstream kinase JAK2 of Stat3 was added in to the culture fluid. 24, 48, and 72 hours later flow cytometry was used to examine the apoptosis of the cells.

RESULTS

The mRNA expression levels of Stat3 and COX-2 in the colorectal cancer tissues were 1.97 and 1.88 times those of the adjacent normal tissues (both P < 0.05). The mRNA expression levels of Stat3 and COX-2 in the colorectal cancer tissues of the patients with lymph node metastasis were both significantly higher than those of the patients without lymph node metastasis (both P < 0.05). The mRNA expression levels of Stat3 and COX-2 in the colorectal cancer tissues of the patients of cancer with low differentiation were both significantly higher than those of the patients with high differentiation (both P < 0.05). Pearson correlation analysis showed that Stat3 mRNA expression was linearly correlated with COX-2 mRNA expression (r = 0.749, P < 0.01). The protein expression levels of Stat3 and COX-2 in the colorectal caner tissues were significantly higher than those in the adjacent normal tissues (both P < 0.01). AG490 time and dose-dependently inhibited the growth of the HKC cells, induced apoptosis of the HKC cells, and down-regulated the protein expression of Stas3 and COX-2.

CONCLUSION

Overexpression of Stat3 and COX-2 may play a critical role in the development of colorectal cancer. Stat3 pathway influences the proliferation and apoptosis of colorectal cells and COX-2 gene expression. Blockade of the Stat3 signal pathway inhibits the proliferation and promotes the apoptosis of colorectal cancer cells.

[Expression of SARS-CoV in various types of cells in lung tissues]

OBJECTIVE

To investigate the cell types infected by severe acute respiratory syndrome-associated coronavirus (SARS-CoV) in lung tissues and explore the mechanism of lung injury in SARS.

METHODS

In-situ hybridization(ISH) and immunohistochemistry(IHC) double staining was applied to study the lung tissues from 7 SARS cases of Beijing and one of Anhui province. According to SARS-CoV genome sequence, the cDNA probe was synthesized and labelled by digoxin. Immunohistochemically, antibodies of cytokeratin(CK), CD34, CD68, Vimentin and CD3 were applied to demonstrate bronchial epithelial cells, type II pneumocytes, endothelial cells, macrophages, fibroblasts and T cells respectively.

RESULTS

The positive results of in-situ hybridization showed that the lung tissues of all cases expressed SARS-CoV RNA, and positive signals displayed in cytoplasms (purple-blue, NBP-BCIP. ISH-IHC double staining showed that positive signals of both ISH (purple-blue NBT-BCIP and IHC (red-brown, AEC expressed in the cytoplasms (purple and red). The positive results of double staining indicated that bronchial epithelial cells, type II pneumocytes, endothelial cells, macrophages, fibroblasts and T lymphocytes were diffusely infected by SARS-CoV.

CONCLUSION

This study of ISH-IHC double staining in lung tissues of SARS patients showed that bronchial epithelial cells, type II pneumocytes, endothelial cells, macrophages, T lymphocytes and fibroblasts were attacked diffusely in SARS lungs. Various types of cells damaged by SARS-CoV and inflammatory mediators released by those cells play an important role in the pathogenesis of lung injury in SARS.

[Lung pathology and pathogenesis of severe acute respiratory syndrome: a report of six full autopsies]

OBJECTIVE

Severe acute respiratory syndrome (SARS) is an emerging infectious disease that first manifested in humans in November 2002. The SARS-associated coronavirus (SARS-CoV) has been identified as the causal agent, but the pathology and pathogenesis are still not quite clear.

METHODS

Post-mortem lung samples from six patients who died from SARS from April to July 2003 were studied by light and electron microscopy, Masson trichromal staining and immunohistochemistry. Evidence of infection with the SARS-CoV was determined by reverse-transcription PCR (RT-PCR) , serological examination and electron microscopy.

RESULTS

Four of six patients had serological and RT-PCR evidence of recent infection of SARS-CoV. Morphologic changes are summarized as follows: (1) Diffuse and bilateral lung consolidation was seen in all patients (6/6) with increasing lung weight. (2) Diffuse alveolar damage was universal (6/6) with hyaline membrane formation (6/6), intra-alveolar edema/hemorrhage (6/6), fibrin deposition (6/6), pneumocyte desquamation (6/6). A marked disruption in the integrity of the alveolar epithelium was confirmed by immunostaining for the epithelial marker AE1/AE3 (6/6). (3) Type II pneumocytes, with mild hyperplasia, atypia, cytomegaly with granular amphophilic cytoplasm and intracytoplasmic lipid accumulation (5/6). (4) Giant cells in the alveoli were seen in five of 6 patients (5/6) , most of which were positive for the epithelial marker AE1/AE3 (5/6), but some cells were positive for the macrophage marker CD68(2/6). (5) A pronounced increase of macrophages were seen in the alveoli and the interstitium of the lung (6/6), which was confirmed by histological study and immunohistochemistry. (6) Haemophagocytosis was present in five of the 6 patients(5/6). (7) Lung fibrosis was seen in five patients(5/6), with alveolar septa and interstitium thickening(5/6), intraalveolar organizing exudates (6/6) and pleura thickening (4/6). Proliferation of collagen was confirmed by Masson trichromal staining, most of which was type III collagen by immunostaining. The formation of distinctive fibroblast/myofibroblast foci was seen in five patients (5/6) by light microscopy and immunochemistry. (8) Squamous metaplasia of bronchial mucosa was seen in five patients(5/6). (9) Thrombi was seen in all patients(6/6). (10) Accompanying infection was present in two patients, one was bacteria, the other was fungus. In addition, electron microscopy revealed viral particles in the cytoplasm of alveolar epithelial cells and endothelial cells corresponding to coronavirus.

CONCLUSION

Direct injury of SARS-CoV on alveolar epithelium, prominent macrophage infiltration and distinctive fibroblast/myofibroblast proliferation may play major roles in the pathogenesis of SARS.

Multiple organ infection and the pathogenesis of SARS

After >8,000 infections and >700 deaths worldwide, the pathogenesis of the new infectious disease, severe acute respiratory syndrome (SARS), remains poorly understood. We investigated 18 autopsies of patients who had suspected SARS; 8 cases were confirmed as SARS. We evaluated white blood cells from 22 confirmed SARS patients at various stages of the disease. T lymphocyte counts in 65 confirmed and 35 misdiagnosed SARS cases also were analyzed retrospectively. SARS viral particles and genomic sequence were detected in a large number of circulating lymphocytes, monocytes, and lymphoid tissues, as well as in the epithelial cells of the respiratory tract, the mucosa of the intestine, the epithelium of the renal distal tubules, the neurons of the brain, and macrophages in different organs. SARS virus seemed to be capable of infecting multiple cell types in several organs; immune cells and pulmonary epithelium were identified as the main sites of injury. A comprehensive theory of pathogenesis is proposed for SARS with immune and lung damage as key features.