TIPE1 induces apoptosis by negatively regulating Rac1 activation in hepatocellular carcinoma cells

TIPE1 (tumor necrosis factor-α-induced protein 8-like 1 or TNFAIP8L1) is a newly identified member of the TIPE (TNFAIP8) family, which play roles in regulating cell death. However, the biologic functions of TIPE1 in physiologic and pathologic conditions are largely unknown. Here, we report the roles of TIPE1 in hepatocellular carcinoma (HCC). Evaluated by immunohistochemical staining, HCC tissues showed significantly downregulated TIPE1 expression compared with adjacent non-tumor tissues, which positively correlated with tumor pathologic grades and patient survival. Using a homograft tumor model in Balb/c mice, we discovered that TIPE1 significantly diminished the growth and tumor weight of murine liver cancer homografts. Consistently, TIPE1 inhibited both cell growth and colony formation ability of cultured HCC cell lines, which was further identified to be due to TIPE1-inducing apoptosis in a caspase-independent, necrostatin-1 (Nec-1)-insensitive manner. Furthermore, mechanistic investigations revealed that TIPE1 interacted with Rac1, and inhibited the activation of Rac1 and its downstream p65 and c-Jun N-terminal kinase pathway. Moreover, overexpression of constitutively active Rac1 partially rescued the apoptosis induced by TIPE1, and Rac1 knockdown significantly restored the deregulated cell growth induced by TIPE1 small interfering RNA. Our findings revealed that TIPE1 induced apoptosis in HCC cells by negatively regulating Rac1 pathway, and loss of TIPE1 might be a new prognostic indicator for HCC patients.

Structure Development in Melt Spinning and Cold Drawing of Poly(ethylene-co-octene) Copolymer

An experimental study of melt spinning and cold drawing of polyethylene and its Dow Chemical INSITEØ catalyst octene copolymers was carried out. The structure and morphology of both melt spun and cold drawing fibers were investigated using wide angle x-ray diffraction (WAXD), small angle x-ray scattering (SAXS), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and birefringence. Up to 5.9 mol.% octene, the fibers exhibit only the Bunn orthorhombic crystal structure. Fibers with 9.7 mol.% and 13.3 mol.% octene, whose DSC crystallinity is 0.23 and below, have an additional reflection at about 0.45nm. The Hermans-Stein orientation factors for the melt spun fibers were determined and correlated with spinline stress. Cold drawn polyethylene fibers exhibited additional reflection at 0.45, 0.38 and 0.35nm which may be associated with the Tanaka-Seto et al. monoclinic unit cell. The copolymers contained a decreased monoclinic level which disappears at about 5.9 mol.%. However, a broad reflection at 0.45nm, reappears at 9.7 mol.% octene. This reflection is also present at the 13.3 mol.% level. It is surmised that a pseudohexagonal or mesomorphic structure is developing. The Hermans-Stein orientation factors were determined for the drawn fibers as a function of cold draw ratio. Drawing results in high crystalline orientation and fibrillation for polyethylene fibers. For copolymers, with higher octene content, the fibrillation decreases.

High-resolution CT findings of pulmonary infections after orthotopic liver transplantation in 453 patients

OBJECTIVES

The objective of this study was to review the high-resolution CT (HRCT) findings in patients with pulmonary infection after orthotopic liver transplantation (OLT) and to determine distinguishing findings among the various types of infection.

METHODS

This study included 453 consecutive liver transplant recipients with pulmonary infection, on whom HRCT of the chest was performed within 24 h of the beginning of symptoms and for whom proven diagnosis had taken place within 1 week of the onset of symptoms. Two radiologists analysed the CT images; final decisions regarding the findings were reached by consensus.

RESULTS

Bacterial and viral pneumonia made up the bulk of infections (63.4% and 29.4%, respectively), followed by fungal infiltrates (24.5%). Large nodules were most common in patients with fungal pneumonia, having been seen in 38 (54%) of the 70 patients with fungal pneumonia, 22 (10%) of 220 with bacterial pneumonia (p=0.0059) and 6 (8%) of 78 with viral pneumonia (p=0.0011). The halo sign was also more frequent in patients with fungal pneumonia, having been seen in 38 (54%) of the 70 patients with fungal pneumonia, 17 (8%) of 220 with bacterial pneumonia (p=0.0026) and 7 (9%) of 78 with viral pneumonia (p=0.0015). There was no statistically significant difference in the prevalence of the other HRCT patterns including air-space consolidation, ground-glass attenuation and small nodules among bacterial, viral and fungal infections (all p>0.05).

CONCLUSION

The presence of large nodules with the halo sign is most suggestive of fungal infection after OLT. Other HRCT patterns are not helpful in distinguishing among the various types of infection seen in liver transplant recipients.

320-detector CT coronary angiography with prospective and retrospective electrocardiogram gating in a single heartbeat: comparison of image quality and radiation dose

OBJECTIVES

To compare the image quality, radiation dose and diagnostic accuracy of 320-detector CT coronary angiography with prospective and retrospective electrocardiogram (ECG) gating in a single heartbeat.

METHODS

Two independent reviewers separately scored image quality of coronary artery segment for 480 cardiac CT studies in a prospective group and a retrospective group (240 patients with a heart rate <65 beats per minute in each group). The two groups matched well for clinical characteristics and CT parameters. There was good agreement for image quality scores of coronary artery segment between the independent reviewers (κ=0.73). Of the 7023 coronary artery segments, the image quality scores of the prospective group and retrospective group were not significantly different (p>0.05). The mean radiation dose was 10.0 ± 3.5 mSv (range 6.2-21.6 mSv) for prospective ECG gating at 65-85% of R-R interval (the interval between the R-wave of one heartbeat to the R-wave of the next). The mean radiation dose for retrospective ECG-triggered modulated scans was 23.2 ± 3.4 mSv (range 17-27.4 mSv). The mean radiation dose was 57% lower for prospective gating than for retrospective gating (p<0.01).

RESULTS

Compared with coronary angiography, the results for prospective vs retrospective ECG gating were 92% vs 90% for sensitivity (p=0.23), 89% vs 91% for specificity (p=0.19), 90% vs 93% for positive predictive value (p=0.25) and 92% vs 95% for negative predictive value (p=0.21) for lesions with ≥50% stenosis, respectively.

CONCLUSION

320-detector CT coronary angiography performed with prospective ECG gating has similar subjective image quality scores, but a 57% lower radiation dose than retrospective ECG gating in a single heartbeat.

First-time donors responding to a national disaster may be an untapped resource for the blood centre

BACKGROUND

On 12 May 2008, a severe earthquake struck Sichuan in China. Many people donated blood for the first time, leading us to question whether these donors might become repeat donors in the future. The return pattern of post-earthquake first-time donors (PEFTD) was compared with that of first-time donors (FTD) in a comparable period.

METHODS

Demographic characteristics, transfusion-transmissible infection rates and 1-year return rates were compared between 5147 PEFTD (5/13-5/19, 2008) and 3176 FTD (5/13-5/19, 2009) from five Chinese blood centres using chi-squared tests. Adjusted logistic regression was used to detect earthquake effect on donor return.

RESULTS

Post-earthquake first-time donors were more frequently between 26 and 45 years, men, and better educated compared with the control group. Slightly higher but not statistically significant increased rates of hepatitis B virus surface antigen (HBsAg) (0·87% vs. 0·50%, P=0·054), hepatitis C virus (HCV) (0·70% vs. 0·63%, P=0·414), syphilis (0·9% vs. 0·7%, P=0·489) and lower rates of human immunodeficiency virus (HIV) (0·31% vs. 0·60%, P=0·078) reactivity were detected for PEFTD. The 1-year return rate for PEFTD was significantly lower than that of the controls (8·0% vs. 13·0%, P<0·001). After adjusting for demographic factors, donation volume and sites, the PEFTD were less likely to return in 1 year than the controls (OR: 0·520; 95% CI: 0·442, 0·611).

CONCLUSION

Post-earthquake first-time donors may be less likely to donate again without continuing motivation strategies. Further studies on PEFTD's lack of motivation to return for donation are needed to design recruitment strategies to convert PEFTD to become repeat donors to continuously replenish the blood supply.

Radiological and clinical findings of 25 patients with invasive pulmonary aspergillosis: retrospective analysis of 2150 liver transplantation cases

OBJECTIVE

The purpose of this study was to evaluate the radiological and clinical findings of invasive pulmonary aspergillosis (IPA) after liver transplantation.

METHODS

This study included 25 consecutive liver transplant recipients with histologically confirmed IPA after liver transplantation. Radiological examinations performed for diagnosis were available in all patients. Clinical findings and changes in clinical response and radiological findings after treatment were also evaluated.

RESULTS

3 main radiological findings were identified: nodules, 64% (16/25); masses, 36% (9/25); and consolidations in a patchy pattern, 20% (5/25). A tree-in-bud pattern was found in 12% (3/25) of patients. In 8 (32%) of 25 patients, we found a combination of 2 or more of these signs: 5 (20%) patients presented with concurrent nodules accompanied by patchy consolidations and/or tree-in-bud, and 3 (12%) patients showed masses accompanied by large consolidations. A halo sign was observed in 20 (80%) of 25 patients. Hypodense sign and cavitary lesions were encountered in 17 (68%) of 25 patients. Follow-up radiological findings after treatment showed improvement in 18 patients, no change in 4 patients and progression in 3 patients. There were three aspergillosis-associated deaths during the follow-up period. The onset time of IPA was a median of 31 days after transplantation. The most common symptom at diagnosis was fever (n=15). None of the 25 patients had leukopaenia at the time of the diagnosis of IPA.

CONCLUSIONS

The most common radiological findings of IPA after liver transplantation are multiple nodules with or without halo sign, masses and consolidations, which usually appear about 1 month after transplantation.

Enhancement of osteoclastogenic activity in osteolytic prostate cancer cells by physical contact with osteoblasts

BACKGROUND

The interaction between prostate cancer cells and osteoblasts is critical for the development of bone metastasis. Metastatic cancer cells may physically contact osteoblasts in the bone microenvironment; however, the biological significance of this interaction is not fully understood.

METHODS

Human prostate cancer cells (the osteolytic cell line PC-3 and the osteoblastic cell line MDA-PCa 2b) and human osteoblasts (hFOB1.19) were cocultured under two different conditions (bilayer and contact conditions). Differential gene expression profiles of prostate cancer cells were then investigated using microarray analysis. Differentially expressed genes were analysed using RT-PCR and western blotting, and the effect of anti-cadherin neutralising antibodies on their expression was assayed. The osteoclastogenic activity of cells grown under these different conditions was also investigated using an in vitro assay.

RESULTS

When PC-3 or MDA-PCa 2b cells were cocultured with hFOB1.19 cells under contact conditions, the expression of eight genes was upregulated and that of one gene was downregulated in PC-3 cells compared with gene expression in bilayer culture. No differentially expressed genes were detected in MDA-PCa 2b cells. Four of the eight upregulated genes (interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), IL-6 and the third component of complement (C3)) have already been reported to participate in osteoclastogenesis. Indeed, a cell lysate of PC-3 cells grown under contact coculture conditions significantly enhanced osteoclastogenesis in vitro (P<0.005). neutralisation of cadherin-11 with a specific antibody inhibited upregulation of COX-2 and C3 mRNA in PC-3 cells. In contrast, neutralisation of N-cadherin induced upregulation of COX-2 mRNA.

CONCLUSION

Physical contact between osteolytic prostate cancer cells and osteoblasts may upregulate osteoclastogenesis-related gene expression in prostate cancer cells and enhance osteoclastogenesis. Additionally, cadherin-11 and N-cadherin are involved in this process. These data provide evidence supporting new therapies of prostate cancer bone metastasis that target direct cancer-cell-osteoblast cell-cell contact.

Effects of spironolactone on atrial structural remodelling in a canine model of atrial fibrillation produced by prolonged atrial pacing

BACKGROUND AND PURPOSE

Suppression of the renin-angiotensin-aldosterone system can prevent atrial fibrillation (AF) by attenuating atrial structural remodelling but the role of aldosterone in AF prevention has not been investigated thoroughly. We explored whether the aldosterone antagonist, spironolactone, could improve atrial structural remodelling in long-term rapid pacing-induced AF.

EXPERIMENTAL APPROACH

Three groups of dogs were used, sham-operated, control and spironolactone-treated groups. Dogs in the control and spironolactone groups had right atrial pacing for 6 weeks. The spironolactone group was given spironolactone 1 week before and during the atrial pacing. After 6 weeks of pacing, atrial structural and functional changes were assessed by echocardiography, haemodynamic parameters by cardiac catheterization, histopathological changes by light and electron microscopy and cardiomyocyte apoptosis by TUNEL. Caspase-3, Bcl-2, bax, calpain I, calpastatin, matrix metalloproteinase (MMP)-9 and tissue inhibitors of metalloproteinase (TIMP)-1 were analysed by immunohistochemistry and Western blotting. The inducibility and duration of AF were measured by atrial burst pacing.

KEY RESULTS

After atrial pacing, the proportion of TUNEL positive cells, myolysis, atrial fibrosis and dilatation were all significantly increased and these changes were inhibited by spironolactone. Spironolactone treatment reversed the increased expression of caspase-3, bax, calpain I and MMP-9 and the decreased level of Bcl-2, calpastatin and TIMP-1, induced by chronic atrial pacing. Also spironolactone prevented the increased inducibility and duration of AF, induced by tachypacing.

CONCLUSIONS AND IMPLICATIONS

Treatment with spironolactone prevented myocardial apoptosis, myolysis, atrial fibrosis and dilatation, suggesting a possible beneficial effect of aldosterone antagonism on atrial structural remodelling in AF.

Partial splenic embolization for hypersplenism in cirrhosis: a long-term outcome in 62 patients

BACKGROUND

Although partial splenic embolization (PSE) has been widely used for treatment of leucocytopaenia and thrombocytopaenia in cirrhosis, only few studies on the correlation between splenic infarction rate and long-term outcome of partial splenic embolization have been reported so far.

AIM

To evaluate long-term results of partial splenic embolization with different infarction rates in cirrhotic patients with hypersplenism.

METHODS

Sixty-two consecutive patients with hypersplenism in cirrhosis received partial splenic embolization. According to the splenic infarction rate after partial splenic embolization, the patients were divided into three groups: more than 70% in group A (n=12), 50-70% in group B (n=34), and less than 50% in group C (n=16). The post-partial splenic embolization following-up time was 5 years.

RESULTS

Before partial splenic embolization, there were no significant differences among the three groups with respect to sex, age, splenic volume, Child-Pugh class, oesophageal varices, and peripheral blood cell counts. After partial splenic embolization, the short- and long-term outcomes of leucocyte and platelet counts showed significant difference among the three groups (P<0.001). In groups A and B, the leucocyte and platelet counts after partial splenic embolization remained significantly higher than those before partial splenic embolization for 2 weeks to 5 years (P<0.05), the post-partial splenic embolization leucocyte and platelet counts was even higher in group A than in group B; while in group C, leucocyte and platelet count improvement only lasted for 6 months after partial splenic embolization. No significant changes were observed concerning blood red cell counts and liver function parameters after partial splenic embolization among the three groups. Severe complications occurred in six patients (50%) in group A and three patients (8.8%) in group B (P<0.05), while in group C, no severe complications developed.

CONCLUSIONS

In partial splenic embolization, the splenic infarction rate should be limited to 50%-70% in order to ensure the long-term efficacy in alleviating hypersplenism and reduce complications.

Knowledge, attitude and practice survey regarding blood donation in a Northwestern Chinese city

Recruitment of low-risk blood donors in developing countries is challenging. We studied the attitudes towards blood donation in several populations in a city in Western China. A survey of knowledge, attitude and practice was performed including 1280 individuals from eight distinct populations in Urumqi, Xinjiang Uyghur Autonomous Region, China. Included were Han Chinese and Uyghur populations of blood donors, non-donors, injection drug users, students and factory workers. Knowledge about blood donation varied between the groups. Factors motivating blood donation included social pressure, desire to know screening results and altruism. Inhibiting factors included fear of contracting an infection and other adverse health effects, including loss of vitality. Misconceptions about the effects of blood donation are widespread, even among educated persons in Urumqi. Fear of acquiring a serious infection may have been increased by the reports of HIV acquisition during plasma donations in China.