[The comparison between endoscopic and surgical treatment of delayed iatrogenic bile duct injury by propensity score matching]

Objective: To compare the safety and clinical efficacy of endoscopic and surgical treatment of patients with delayed iatrogenic bile duct injury (DBDI) with severity (SG) grade 1 to 2. Methods: The clinical data of 129 patients with SG grade 1 to 2 DBDI who received endoscopic or surgical treatment in the First Hospital of Lanzhou University from November 2007 to November 2021 were retrospectively collected. There were 46 males and 83 females,aged (M(IQR)) 54(22)years(range: 21 to 82 years). The baseline data of the two groups were matched 1∶1 by propensity score matching(caliper value was 0.2). Independent sample t test,rank sum test,χ2 test or Fisher exact probability test were used to analyze the data of the two matched groups. Results: There were 48 patients in each of the endoscopic treatment and surgical groups after matching,and there was no difference in general information between the two groups(both P>0.05). The bile duct injury-repair interval and intraoperative anesthesia complications were not statistically significant between the two groups after matching(all P>0.05). Compared with the surgical group, patients in the endoscopic treatment group had significantly shorter operative time(50 (30) minutes vs. 185 (100) minutes, Z=7.675,P<0.01) and postoperative hospital stay(5 (5) days vs. 12 (7) days, Z=5.848, P<0.01).For safety,there was no statistical difference in the incidence of immediate postoperative complications between the two groups with Clavien-Dindo classification of surgical complications<Ⅲ;the incidence of serious postoperative complications (Clavien-Dindo classification of surgical complications≥Ⅲ) was significantly higher in the surgical group than in the endoscopic treatment group(P=0.012). The incidence of long-term postoperative complications was not statistically different between the two groups(28.1% vs. 20.7%,P=0.562). In terms of efficacy,the postoperative liver function indexes of patients in both groups improved significantly compared with the preoperative period and returned to normal or near normal levels; the postoperative infection indexes of both groups showed an increasing trend,but were within the normal range. Of the 96 patients in both groups,61 obtained follow-up,and the follow-up time was (89.4±48.0)months(range: 3 to 165 months),and there was no statistical difference between the two groups(P=0.079). The probability of excellent long-term follow-up (78.1% vs. 86.2%) was not statistically different between the two groups(P=0.412).In patients with Strasberg-Bismuth type E1,the probability of excellent long-term follow-up was higher in the endoscopic treatment group compared with the surgical group(13/14 vs. 2/5,P=0.037). Conclusions: For DBDI patients with SG grade 1 to 2 and bile duct continuity,endoscopy can be used as the first deterministic treatment. The advantages of endoscopic therapy compared to surgery are the lower incidence of postoperative serious complications,and the shorter duration of surgery and postoperative hospital stay.

A two-ward acute care hospital outbreak of SARS-CoV-2 delta variant including a point-source outbreak associated with the use of a mobile vital signs cart and sub-optimal doffing of personal protective equipment

BACKGROUND

The arrival of the Delta variant of SARS-CoV-2 was associated with increased transmissibility and illness of greater severity. Reports of nosocomial outbreaks of Delta variant COVID-19 in acute care hospitals have been described but control measures varied widely.

AIM

Epidemiological investigation of a linked two-ward COVID-19 Delta variant outbreak was conducted to elucidate its source, risk factors, and control measures.

METHODS

Investigations included epidemiologic analysis, detailed case review serial SARS-CoV-2 reverse transcriptase-polymerase chain reaction (RT-PCR) testing of patients and healthcare workers (HCWs), viral culture, environmental swabbing, HCW-unaware personal protective equipment (PPE) audits, ventilation assessments, and the use of whole genome sequencing (WGS).

FINDINGS

This linked two-ward outbreak resulted in 17 patient and 12 HCW cases, despite an 83% vaccination rate. In this setting, suboptimal adherence and compliance to PPE protocols, suboptimal hand hygiene, multi-bedded rooms, and a contaminated vital signs cart with potential fomite or spread via the hands of HCWs were identified as significant risk factors for nosocomial COVID-19 infection. Sudden onset of symptoms, within 72 h, was observed in 79% of all Ward 2 patients, and 93% of all cases (patients and HCWs) on Ward 2 occurred within one incubation period, consistent with a point-source outbreak. RT-PCR assays showed low cycle threshold (C_T) values, indicating high viral load from environmental swabs including the vital signs cart. WGS results with ≤3 SNP differences between specimens were observed.

CONCLUSION

Outbreaks on both wards settled rapidly, within 3 weeks, using a `back-to-basics' approach without extraordinary measures or changes to standard PPE requirements. Strict adherence to recommended PPE, hand hygiene, education, co-operation from HCWs, including testing and interviews, and additional measures such as limiting movement of patients and staff temporarily were all deemed to have contributed to prompt resolution of the outbreak.

Effects of stand condition and root density on fine-root dynamics across root functional groups in a subtropical montane forest

Fine roots play key roles in belowground C cycling in terrestrial ecosystems. Based on their distinct functions, fine roots are either absorptive fine roots (AFRs) or transport fine roots (TFRs). However, the function-based fine root dynamics of trees and their responses to forest stand properties remain unclear. Here, we studied the dynamics of AFRs and TFRs and their responses to stand conditions and root density in a subtropical montane mixed forest based on a 2-a root window experiment. Mean (± SE) annual production, mortality, and turnover rate of AFRs were 7.87 ± 0.17 m m^-2 a^-1, 8.13 ± 0.20 m m^-2 a^-1and 2.96 ± 0.24 a^-1, respectively, compared with 7.09 ± 0.17 m m^-2 a^-1, 4.59 ± 0.17 m m^-2 a^-1, and 2.01 ± 0.22 a^-1, respectively, for TFRs. The production and mortality of fine roots were significantly higher in high root-density sites than in low-root density sites, whereas the turnover of fine roots was faster in the low root-density sites. Furthermore, root density had a larger positive effect than other environmental factors on TFR production but had no obvious impact on AFR production. Tree species diversity had an apparent positive effect on AFR production and was the crucial driver of AFR production, probably due to a complementary effect, but had no evident impact on TFR. Both tree density and tree species diversity were positively correlated with the mortality of AFRs and negatively related to the turnover of TFRs, suggesting that higher root density caused stronger competition for rooting space and that plants tend to reduce maintenance costs by decreasing TFR turnover. These findings illustrated the importance of root functional groups in understanding root dynamics and their responses to changes in environmental conditions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11676-022-01514-0.

Linking soil organic carbon stock to microbial stoichiometry, carbon sequestration and microenvironment under long-term forest conversion

Forest conversion can drastically impact carbon (C) and nutrient processes and microbial stoichiometry, which will modify soil organic C (SOC) stock. However, SOC stock dynamics and its underlying mechanisms induced by long-term forest conversion remain unclear. Three well-protected plantations converted from natural forests for 36 years were compared, i.e., Cryptomeria fortunei (CF), Metasequoia glyptostroboides (MG) and Cunninghamia lanceolata (CL), with a natural forest (NF) as a control. SOC stock size and stability across three soil depths (0-10, 10-30 and 30-60 cm) were examined with aggregate-based method. Forest floors and fine roots were treated as C and nutrient inputs while soil respiration (Rs) was treated as C output. Soil microbial biomass C, nitrogen and phosphorus were measured to calculate microbial stoichiometry, as well as microenvironment and soil physicochemical properties. The relationships between SOC stock (size and stability) and these factors were explored using structural equation model. The results showed that microbial stoichiometry had strong or strict homeostasis at each soil depth. At 0-10 cm soil deep, SOC stock size varied with tree species (following the rank of CL > NF ≈ CF > MG) but its stability increased in all forest conversion types, regulated by forest floor quantity and quality associated with Rs; at 10-30 cm soil deep, the SOC stock sizes decreased in CF and MG, but SOC stock stability increased in MG, jointly driven by fine root quality and microenvironment; at 30-60 cm soil deep, SOC stock size decreased but its stability increased in MG, whereas both its size and stability had few changes in CF or CL, modified by soil physicochemical property associated with microbial stoichiometry and Rs. Overall, the effects of microbial stoichiometry and microenvironment on SOC stock were not pronounced. Thus, SOC stock size changed with soil depth and tree species but its stability tended to be steady at all depths varying with tree species. These results suggest that SOC stock size and stability are mainly determined by self-regulation process of forest ecosystems over more than three-decade after forest conversion, which will help us more accurately assess C sequestration strategies regarding long-term forest conversion.

Development and usability test of an intelligent cardiovascular risk elimination application for patients with coronary heart disease

Background

The mortality of coronary heart disease (CHD) can be largely reduced by improving CHD risk factors through facilitating adherence to unhealthy lifestyle modification (UhLM) and secondary preventive medications (SPMs). Current interventions, however, have been unsatisfactory worldwide.

Purpose

To develop an Individualized, Intelligent and Integrated Cardiovascular Application for Risk Elimination system (iCARE) for facilitating adherence to UhLM and SPMs, and test its usability and feasibility for implementation.

Methods

Based on a set of individualized interventions formulated in our preliminary work, we developed iCARE using mHealth techniques and a user-centred approach, which included 3 phases: (1) identifying patient preferences regarding formats for providing interventions; (2) designing the functions, architecture, and user interface (UI); (3) developing the iCARE using prototyping techniques. Usability test was conducted in patients with acute coronary syndromes and/or underwent percutaneous coronary intervention from January to March 2019 in two University affiliated hospitals in our city. The iCARE was implemented in 4 cardiac units of the same hospitals thereafter.

Results

The iCARE architecture and UI are displayed in Fig 1. Different from most current available mHealth CHD management system, the iCARE has a set of interventions and IF-THEN algorithms triggering interventions to ensure that patients receive individualized recommendations for UhLM and SPMs adherence. To improve effectiveness of iCARE interventions, visualization was used to augment patients' perceptions of risks of non-adherence to UhLM and SPMs, and effectiveness of adopting healthy lifestyles etc. Interventions are triggered by results of initial assessment and health data from daily monitoring. The initial assessment is conducted before patients are discharged, and a health report as well as individualized goals for risk reduction are formulated automatically. Daily diet, physical activities, smoking, medication adherence, blood pressure, blood sugar, and symptoms are monitored either through wearable devices or manual entry. Instant and individualized feedbacks as well as recommended actions are sent to patients automatically. A build-in artificial intelligent Q-A function was also included in iCARE. For the usability test, 88 patients with 71.3% male and mean age of 60 (SD 9.9) were recruited, 87.5% were satisfied with iCARE; 89.5% and 81.4% reported that iCARE was useful and easy to use, respectively. Currently, a total of 201 patients with 83.1% male and mean age of 54 (SD 10.2) were recruited from June 2019 to January 2020, and 46 of them have been followed up for 3 months.

Conclusions

The iCARE has achieved its functions of serving as an individualized and intelligent CHD management tool to improve adherence to UhLM and SPMs. The usability is satisfactory and it is feasible to implement in clinical settings.

Figure 1. The iCARE system. iCARE, Individualized, Intelligent and Integrated Cardiovascular Applicaton for Risk Elimination (iCARE) system, CHD, coronary heart disease.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Natural Science Funding of China

Higher carbon sequestration potential and stability for deep soil compared to surface soil regardless of nitrogen addition in a subtropical forest

Background

Labile carbon input could stimulate soil organic carbon (SOC) mineralization through priming effect, resulting in soil carbon (C) loss. Meanwhile, labile C could also be transformed by microorganisms in soil as the processes of new C sequestration and stabilization. Previous studies showed the magnitude of priming effect could be affected by soil depth and nitrogen (N). However, it remains unknown how the soil depth and N availability affect the amount and stability of the new sequestrated C, which complicates the prediction of C dynamics.

Methods

A 20-day incubation experiment was conducted by adding ¹³C labeled glucose and NH₄NO₃ to study the effects of soil depth and nitrogen addition on the net C sequestration. SOC was fractioned into seven fractions and grouped into three functional C pools to assess the stabilization of the new sequestrated C.

Results

Our results showed that glucose addition caused positive priming in both soil depths, and N addition significantly reduced the priming effect. After 20 days of incubation, deep soil had a higher C sequestration potential (48% glucose-C) than surface soil (43% glucose-C). The C sequestration potential was not affected by N addition in both soil depths. Positive net C sequestration was observed with higher amount of retained glucose-C than that of stimulated mineralized SOC for both soil depths. The distribution of new sequestrated C in the seven fractions was significantly affected by soil depth, but not N addition. Compared to deep soil, the new C in surface soil was more distributed in the non-protected C pool (including water extracted organic C, light fraction and sand fraction) and less distributed in the clay fraction. These results suggested that the new C in deep soil was more stable than that in surface soil. Compared to the native SOC for both soil depths, the new sequestrated C was more distributed in non-protected C pool and less distributed in biochemically protected C pool (non-hydrolyzable silt and clay fractions). The higher carbon sequestration potential and stability in deep soil suggested that deep soil has a greater role on C sequestration in forest ecosystems.

[Renal angiomyolipoma with epithelial cysts: a clinicopathological analysis of four cases]

Objective: To investigate the clinicopathological features,diagnosis and differential diagnosis of renal angiomyolipoma with epithelial cysts(AMLEC). Methods: Four cases of renal AMLEC diagnosed between January 2014 and June 2019 at the Department of Pathology,Zhejiang Provincial People's Hospital were subjected to clinicopathological, histological and immunohistochemistry analyses along with a literature review. Results: All the four patients were females and aged from 19 to 52 years (mean 34.5 years). Three cases were accidentally discovered by physical examination, and the medical history was 1 to 6 years. The preoperative imaging Bosniak classification was grade Ⅲ in 3 and grade Ⅳ in 1 case. The maximum diameter of the tumor ranged from 2.5 to 9.0 cm (average 5.0 cm). Histologically, all of the 4 tumors showed three histological components: (1) simple epithelial cysts lined by a layer of cuboidal/low-columnar to occasionally, hobnailcells; (2) a thin, compact subepithelial "cambium-like" layer of cellular, mullerian-like short spindle cell stromas with prominent admixedchronic inflammation; (3) a outermost layer of thick, long-fascicles of smooth muscle-like stromas, often surrounded by dysplastic, tortuous thick-walled blood vessels. There was often a prominent lymphatic channel network in the smooth muscle component forming slit like branched and curvilinear spaces. None of the 4 tumors had fat content.Immunohistochemically, the epithelial cells lining the cysts strongly expressed PAX8 and CK7. The subepithelial "cambium-like" stromas strongly expressed melanocytic markers (HMB45, Melan A, Cathspin K, MiTF) and mullerian markers (ER,PR,CD10), and were negative for smooth-muscle markers(SMA,desmin,calponin). The outermost layer of smooth muscle-like stromas strongly expressed smooth-muscle markers, and were only focally positive for melanocytic and mullerian markers. Follow-up information was obtained in 3 cases, among which no evidence of tumor recurrence or metastasis was found at 3, 5, and 66 months of follow-up, respectively. Conclusions: Renal AMLEC is a rare histological subtype of angiomyolipoma with benign biological behavior, and has characteristic histological and immunophenotypic characteristics.Pathologists should be familiar with the clinicopathological appearances of AMLEC and include it in the differential diagnostic spectrums of renal tumors with biphasic epithelial and mesenchymal features.

288Thrombotic events in bleeding patients treated with andexanet alpha: an ANNEXA-4 sub-study

Background/Introduction

Andexanet alfa (“andexanet”) was developed as a specific reversal agent for patients with major bleeding while using factor Xa (FXa) inhibitors. While thrombotic events (TEs) have been reported in patients receiving andexanet, the scope, nature, and timing of these events have not been fully characterized.

Purpose

The ANNEXA-4 study was a prospective, single-arm, open-label clinical trial that evaluated the safety and efficacy of andexanet in patients with acute major bleeding. In this secondary analysis, the occurrence of TEs was investigated.

Methods

Patients presenting with acute major bleeding within 18 hours after their last dose of FXa inhibitor were treated with andexanet. Safety outcomes, including TEs (reviewed by an adjudication committee), were evaluated at 30 days.

Results

Among 352 patients treated with andexanet, 34 (9.7%) experienced one or more TEs (Table). Strokes and deep vein thromboses were the most frequent TE types. Compared to patients with arterial TEs, patients with venous TEs were more likely to have been originally anticoagulated for venous thromboembolism. Median time to first TE was 10.5 days (Figure); time to event was shorter for arterial TEs than for venous TEs. TEs were nonfatal for most patients. Subgroups by age, bleed type, baseline anti-fXa activity, FXa inhibitor dose, and andexanet dose were not associated with the occurrence of TEs. Of the 34 TE patients, 26 (76.4%) had TEs before restart of any (full or prophylactic) anticoagulation; all first TEs occurred in patients not receiving oral anticoagulation. No TEs occurred after resumption of oral anticoagulation (N=100).

Table 1. Thrombotic event characteristics Characteristic Result (n/N [%]) TE type   Strokes 14/352 (4.0%)   Deep vein thromboses 13/352 (3.7%)   Myocardial infarctions 7/352 (2.0%)   Pulmonary embolisms 5/352 (1.4%)   Transient ischemic attacks 1/352 (0.3%) Bleed type   Intracranial 23/227 (10.1%)   Gastrointestinal 7/90 (7.8%)   Other 4/35 (11.4%) Arterial TEs   Anticoagulated for AF 17/22 (77.3%)   Anticoagulated for VTE 6/22 (27.3%) Venous TEs   Anticoagulated for AF 11/18 (61.1%)   Anticoagulated for VTE 8/18 (44.4%)   Median time to first TE 10.5 days   Arterial 6 days   Venous 15 days Outcome   Fatal 7/34 (20.6%)   Nonfatal 27/34 (79.4%) AF = atrial fibrillation; n = number of patients with TEs; N = total number of patients for each characteristic; TE = thrombotic event; VTE = venous thromboembolism.

Figure 1. Thrombotic Events Over Time

Conclusions

In patients with FXa inhibitor-associated acute major bleeding treated with andexanet, TEs occurred a rate not unexpected given the high thrombotic risk of the population. No factors predictive of TEs were identified. Resumption of anticoagulation was associated with fewer TEs.

Acknowledgement/Funding

Study funded by Portola Pharmaceuticals, Inc.

[Traditional nasal therapy in Uighur medicine]

Nasal therapy, extensively documented in the ancient Uighur medical literature, is one of the external therapies of Uighur medicine. Based on the relevant records of 14 Uighur medical works, the application, classification, clinical features, and medications characteristics of nasal therapy were preliminarily sorted out. The results show that the nasal therapy can be divided into 7 categories, covering more than 200 kinds of common medicinal herbs, 8 kinds of processing methods and 10 kinds of preparations. Clinically, there is a large number of nasal therapy prescriptions, with flexible administration of prescriptions and medications, significant features of comprehensive therapy, with significance of application for further development.

Zwitterion formation and subsequent carboxylate–pyridinium NH synthon generation through isomerization of 2-anilinonicotinic acid

Structural isomerization of 2-anilinonicotinic acids to 4-anilinonicotinic acids leads to an increase of ΔpK_a, thus leading to the formation of a carboxylate–pyridinium NH dimer in the solid state.

Epidemiology, diagnosis, surgical treatment and prognosis of the pancreatic neuroendocrine tumors: Report of 125 patients from one single center

OBJECTIVE

The objective of the following study is to summarize the epidemiology of pancreatic neuroendocrine tumors (p-NETs) in our single institution, analyze the diagnostic characteristics, share the experience of surgical treatments and discuss the prognostic factors.

METHODS

A retrospective collection and analysis of clinical data of 125 patients with p-NETs which were pathologically confirmed in our hospital from January 2002 to December 2012.

RESULTS

A total of 125 patients of which 52 were males and 73 were females. Totally 92 patients had functional p-NETs, while non-functional p-NETs were diagnosed in 33 patients. The most common operative procedures performed were local resection of pancreatic tumor (47.2%), followed by distal pancreatectomy (29.6%). Thirty patients (28%) had post-operative complications, the most common of which was pancreatic fistula (22.4%). The overall survival rate at 5 years was 68.4%. The 5-year survival rate for patients with functional tumors was 75.1%, compared with 50.0% for those with non-functional tumors (P = 0.021). The survival time of patients with R0 resection was statistically longer than that of patients with Not R0 resection (P < 0.005). In univariate analysis, the most powerful predictors of poor outcome were gender, age, tumor size, functional status, surgical margins, lymph node invasion and distant metastasis. However only surgical margin and distant metastasis were significant predictors in multivariate analysis (P = 0.001, 0.047, respectively).

CONCLUSION

p-NETs are an uncommon and heterogeneous group of tumors, with a rising incidence. Surgery is the most effective treatment. Surgical margin and distant metastasis were the most significant prognostic factors. Radical resection should be taken more into considerations.

[Abnormality of TOP2A expression and its gene copy number variations in neuroblastic tumors]

Objective: To detect TOP2A protein expression and gene copy number alterations, and to analyze related clinical and pathological implications in pediatric neuroblastic tumors (NT). Methods: Immunohistochemistry was used to detect TOP2A protein expression. Fluorescence in situ hybridization (FISH) was used to detect numerical aberrations of TOP2A. Results: TOP2A protein was expressed in 59.1%(52/88) of cases, which was associated with differentiation (P=0.006), Ki-67 index (P<0.01) and MKI (P=0.001). Twenty-eight cases (35.0%, 28/88) showed TOP2A gene amplification, which was correlated with the age (P<0.01), clinical stage (P=0.028), high risk group (P=0.001), Ki-67 index (P=0.040) and differentiation (P=0.014). Survival analysis showed that TOP2A expression was related to survival rate. Multivariate analyses showed that TOP2A expression was an independent predictor for poor prognosis (P=0.010). Conclusions: More than half of the cases show TOP2A expression, which is more likely associated with NB, high Ki-67 index and high MKI. Cases with TOP2A expression have shorter survivals and poorer prognosis. TOP2A amplification is seen in 35% and likely occurs in patients older than 18 months and at advanced INSS stages (Ⅲ and Ⅳ). As a target of the anthracycline-based adjuvant drugs, TOP2A test can be used to select patient with NT for the therapy.

Inhibition of mTOR complex 2 induces GSK3/FBXW7-dependent degradation of sterol regulatory element-binding protein 1 (SREBP1) and suppresses lipogenesis in cancer cells

Cancer cells feature increased de novo lipogenesis. Sterol regulatory element-binding protein 1 (SREBP1), when presented in its mature form (mSREBP1), enhances lipogenesis through increasing transcription of several of its target genes. Mammalian target of rapamycin (mTOR) complexes, mTORC1 and mTORC2, are master regulators of cellular survival, growth and metabolism. A role for mTORC1 in the regulation of SREBP1 activity has been suggested; however the connection between mTORC2 and SREBP1 has not been clearly established and hence is the focus of this study. mTOR kinase inhibitors (e.g., INK128), which inhibit both mTORC1 and mTORC2, decreased mSREBP1 levels in various cancer cell lines. Knockdown of rictor, but not raptor, also decreased mSREBP1. Consistently, reduced mSREBP1 levels were detected in cells deficient in rictor or Sin1 compared to parent or rictor-deficient cells with re-expression of ectopic rictor. Hence it is mTORC2 inhibition that causes mSREBP1 reduction. As a result, expression of the mSREBP1 target genes acetyl-CoA carboxylase and fatty acid synthase was suppressed, accompanied with suppressed lipogenesis in cells exposed to INK128. Moreover, mSREBP1 stability was reduced in cells treated with INK128 or rictor knockdown. Inhibition of proteasome, GSK3 or the E3 ubiquitin ligase, FBXW7, prevented mSREBP1 reduction induced by mTORC2 inhibition. Thus mTORC2 inhibition clearly facilitates GSK3-dependent, FBXW7-mediated mSREBP1 degradation, leading to mSREBP1 reduction. Accordingly, we conclude that mTORC2 positively regulates mSREBP1 stability and lipogenesis. Our findings reveal a novel biological function of mTORC2 in the regulation of lipogenesis and warrant further study in this direction.

Randomized clinical trial of laparoscopic anterior 180° partial versus 360° Nissen fundoplication: 5-year results

Anterior partial fundoplication (AF) has been popularized by a lower risk of mechanical side effects. The question then emerges whether anterior partial wrap has a similar antireflux effect with Nissen fundoplication (NF). We therefore conducted a randomized study to compare the long-term outcome of anterior fundoplication with NF. One hundred patients who enrolled in the trial from May 2003 to March 2005 were randomized to laparoscopic AF or laparoscopic NF. Endoscopy, pH monitoring, manometry, a detailed questionnaire, and a visual analog symptom score were completed preoperative at 6, 12, 24, and 60 months after surgical procedures. The postoperative adverse effects such as dysphagia and flatulence were compared between the two groups. Revision surgery or maintenance proton pump inhibitor therapy was defined as failure. Fifty procedures were performed in each group. The outcome at 5 years follow-up was determined for 96 patients (96%; 49 patients in the AF group and 47 in the NF group). Three patients (3%) died of unrelated causes during follow-up, and one patient changed address. Both fundoplications were found to provide good control of reflux-related symptoms in most of the patients. For 96 patients followed up more than 5 years, gastroesophageal reflux symptoms were well controlled in 81 patients (84.38%); the mean DeMeester scores in the AF group decreased from 106.89 ± 14.12 to 12.67 ± 3.14 and in the NF group from 109.51 ± 17.98 to 10.81 ± 2.65, and the esophagitis was ameliorated visibly. Moreover, there were significantly fewer patients in the AF group who complained of flatulence. Compared with NF, anterior 180° partial fundoplication is an effective treatment of gastroesophageal reflux and associates with fewer postoperative adverse effects.

Molecular characterization of highly tumorigenic cell lines used in a xenograph model to investigate cellular therapy for the treatment of refractory ovarian cancer

e16516

Background: Because current therapies for ovarian cancer (OC) have little impact on the long-term survival, there is a compelling need to develop innovative strategies. Our aim was to characterize OC cell lines which can be utilized to test cellular therapy in combination with cytokines or chemotherapies to elicit a graph versus tumor response to treat refractory OC patients. Methods: SKOV-3-RFP, a red fluorescent protein (RFP) expressing line, was passaged through nude mice to create more tumorigenic lines compared to parental SKOV-3 cells. Three SKOV-3-derived lines were established and characterized for IFNα-2b sensitivity, E-cadherinand CCN1gene expression, and STAT3 activation. The cells were grown in the presence of IFNα-2b to determine proliferative effects. Tumors were harvested when mice became moribund; ascitic fluid (AF) and solid tumor (ST) tissue were snap-frozen. Expression of E-cadherinand CCN1, which have been implicated to play role(s) in OC pathobiology, were analyzed in ST harvested from the mice and from SKOV3-derived lines (SKOV3-RFP, AF1, AF2, and AF3). We investigated the activation status in the SKOV3-derived cells of STAT3, which has been associated with malignant transformation and tumor progression. Results: Parental SKOV3-RFP cells when injected at a dose of 5x106 gave a tumor incidence of 4/6 in 14 weeks. AF1 and AF2, when injected at a dose of 1x106 resulted in 100% tumor incidence in 5-weeks (n = 5). These two lines were also more resistant to IFNα-2b compared to RFP. All SKOV3-derived lines and ST expressed E-cadherin by RT-PCR. None of the SKOV3-derived lines expressed CCN1; however, one of the two AF1 ST tested expressed CCN1. Both AF2 ST evaluated showed weak expression of CCN1. In vitro DNA-binding with electrophoretic mobility shift assay (EMSA), showed AF1 and AF3 cells harbor constitutively-active STAT3, whereas the RFP line does not. Conclusions: The SKOV3-derived lines that we developed will be a better model to test novel OC treatment regiments because these lines exhibit increased resistance to IFNα-2b, are more tumorigenic in a xenograph model, show aberrant STAT3 activation, and tumors harvested from these lines express genes that make these lines more aggressive.

No significant financial relationships to disclose.

Familial hypobetalipoproteinemia: genetics and metabolism

Familial hypobetalipoproteinemia (FHBL), an autosomal dominant disorder, is defined as <5th percentile LDL-cholesterol or apolipoprotein (apo) B in the plasma. FHBL subjects are generally heterozygous and asymptomatic. Three genetic forms exist: (i) premature stop codon specifying mutations of APOB; (ii) FHBL linked to a susceptibility locus on the chromosome 3p21; and (iii) FHBL linked neither to APOB nor to the chromosome 3p21. In heterozygous apoB-defective FHBL, the hepatic VLDL export system is defective because apoB 100, the product of the normal allele, is produced at approximately 25% of normal rate, and truncated apoB is cleared too rapidly. The reduced capacity for hepatic triglyceride export increases hepatic fat three-fold. Indexes of adiposity and insulin action are similar to controls. 'Knock-in' mouse models of apoB truncations resemble human FHBL phenotypes. Liver fat in the chromosome 3p21-linked FHBL is normal. Elucidation of the genetic basis of the non-apoB FHBL could uncover attractive targets for lipid-lowering therapy. (See note added in proof.).

Evidence that the death receptor DR4 is a DNA damage-inducible, p53-regulated gene

DR4 (TRAIL-R1), a member of the tumor necrosis factor receptor superfamily, is a cell surface receptor that triggers the apoptotic machinery upon binding to its ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Although three other TRAIL receptors DR5, DcR1, and DcR2 are induced by DNA damage and are regulated by the wild-type p53 tumor suppressor, it was not known whether these factors also affect DR4 expression. In this study, we found that DR4 expression is also enhanced by DNA damage whether induced by ionizing radiation or by chemotherapeutic agents. The induction was observed predominantly in cells containing wild-type p53 and was similar to the regulation patterns of DR5 and Fas, two other members of the family which are known to be regulated by p53. Transfection of HPV 16 E6 gene into cells with wild-type p53, which decreased the level of p53 protein, resulted in suppression of DR4 induction by DNA-damaging agents. Conversely, introduction of exogenous wild-type p53 through adenovirus infection has led to upregulation of endogenous DR4 in cells with mutant p53. Moreover, the transcription inhibitor actinomycin D abolished DNA-damaging agent-induced DR4 expression. Thus, DR4 appears to be a DNA damage-inducible, p53-regulated gene.

Diminished molecular response to doxorubicin and loss of cardioprotective effect of dexrazoxane in Egr-1 deficient female mice

Doxorubicin (DOX) and VP16 are DNA topoisomerase II inhibitors yet only DOX induces an irreversible cardiotoxicity, likely through DOX-induced oxidative stress. Egr-1 is overexpressed after many stimuli that increase oxidative stress in vitro and after DOX-injection into adult mice in vivo. To investigate Egr-1 function in the heart, we compared the molecular and histological responses of wild type (+/+) and Egr-1 deficient (-/-) female mice to saline, DOX, VP16, the cardioprotectant dexrazoxane (DZR), or DOX+DZR injection. DOX, and to a lesser extent VP16, induced characteristic increases in cardiac muscle and non-muscle genes typical of cardiac damage in +/+ mice, whereas only beta-MHC and Sp1 were increased in -/- mice. DZR-alone treated +/+ mice showed increased cardiomyocyte transnuclear width without a change to the heart to body weight (HW/BW) ratio. However, DZR-alone treated -/- mice had an increased HW/BW, increased cardiomyocyte transnuclear width, and gene expression changes similar to DOX-injected +/+ mice. DZR pre-injection alleviated DOX-induced gene changes in +/+ mice; in DZR+DOX injected -/- mice the increases in cardiac and non-muscle gene expression were equal to, or exceeded that, detected after DOX-alone or DZR-alone injections. We conclude that Egr-1 is required for DOX-induced molecular changes and for DZR-mediated cardioprotection.

Identification of retinamides that are more potent than N-(4-hydroxyphenyl)retinamide in inhibiting growth and inducing apoptosis of human head and neck and lung cancer cells

The synthetic retinoid, N-(4-hydroxyphenyl)retinamide (4HPR), which is currently being evaluated in clinical trials for cancer prevention and therapy, inhibits the growth of a variety of malignant cells through induction of apoptosis. However, in the majority of tumor cells, this inhibitory effect of 4HPR requires high concentrations (>1 microM), which exceed the peak plasma level measured in humans. In the present study, we compared and contrasted the effects of several synthetic retinamides on the growth of human lung and head and neck cancer cells in vitro. We found that some retinamides, especially N-(2-carboxyphenyl)retinamide (2CPR), exhibited better growth inhibitory effects than 4HPR in some of the cell lines. 2CPR exerted potent growth inhibitory effects in 5 of 10 head and neck cancer cell lines and in 1 of 10 lung cancer cell lines (IC(50), <0.8 microM). 2CPR (1 microM) induced apoptosis ranging from 10 to 60% in four of five cell lines, whereas 4HPR was ineffective at the same concentration. Unlike 4HPR, 2CPR (up to 10 microM) failed to induce reactive oxygen species production in these sensitive cell lines but could activate caspases 3 and 7 as well as increase poly(ADP-ribose)polymerase cleavage. Interestingly, the effect of 2CPR on cell growth could be suppressed by the specific retinoic acid receptor pan antagonist AGN193109. Our results suggest that 2CPR acts via retinoic acid receptors and may be a good candidate for prevention and treatment of some head and neck and lung cancers.

Overexpression of BCL2 blocks TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in human lung cancer cells

The tumor necrosis factor (TNF) related apoptosis-inducing ligand (TRAIL or Apo2L) and its receptors are members of the tumor necrosis factor superfamily. TRAIL triggers apoptosis by binding to its two proapoptotic receptors DR4 and DR5, a process which is negatively regulated by binding of TRAIL to its two decoy receptors TRID and TRUNDD. Here, we show that TRAIL effectively induces apoptosis in H460 human non-small-cell lung carcinoma cells via cleavage of caspases 8, 9, 7, 3, and BID, release of cytochrome c from the mitochondria, and cleavage of poly (ADP-ribose) polymerase (PARP). However, overexpression of Bcl2 blocked TRAIL-induced apoptosis in H460 cells, which correlated with the Bcl2 protein levels. Importantly, the release of cytochrome c and cleavage of caspase 7 triggered by TRAIL were considerably blocked in Bcl2 overexpressing cells as compared to vector control cells. Moreover, inhibition of TRAIL-mediated cytochrome c release and caspase 7 activation by Bcl2 correlated with the inability of PARP to be cleaved and the inability of the Bcl2 transfectants to undergo apoptosis. Thus, these results suggest that Bcl2 can serve an anti-apoptotic function during TRAIL-dependent apoptosis by inhibiting the release of cytochrome c and activation of caspase 7, thereby blocking caspase 7-dependent cleavage of cellular substrates.

Augmentation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis by the synthetic retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437) through up-regulation of TRAIL receptors in human lung cancer cells

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis via the death receptors DR4 and DR5 in different transformed cells in vitro and exhibits potent antitumor activity in vivo with minor side effects. The synthetic retinoid CD437 is a potent inducer of apoptosis in cancer cells through increased levels of death receptors. We demonstrate that treatment of human lung cancer cells with a combination of suboptimal concentrations of CD437 and TRAIL enhanced induction of apoptosis in tumor cell lines with wild-type p53 but not in normal lung epithelial cells. CD437 up-regulated DR4 and DR5 expression. The CD437 and TRAIL combination enhanced activation of caspase-3, caspase-7, caspase-8, and caspase-9 and the subsequent cleavage of poly(ADP-ribose) polymerase and DNA fragmentation factor 45. Caspase inhibitors blocked the induction of apoptosis by this combination. Moreover, this combination induced Bid cleavage and increased cytochrome c release from mitochondria. These results suggest that the mechanism of enhanced apoptosis by this combination involves p53-dependent increase of death receptors by CD437, activation of these receptors by TRAIL, enhanced Bid cleavage, release of cytochrome c, and activation of caspase-3, caspase-7, caspase-8, and caspase-9. These findings suggest a novel strategy for the prevention and treatment of human lung cancer with the CD437 and TRAIL combination.

Induction of Fas expression and augmentation of Fas/Fas ligand-mediated apoptosis by the synthetic retinoid CD437 in human lung cancer cells

The synthetic retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437) induces apoptosis in a variety of cancer cells. Recently, we demonstrated that CD437 induces apoptosis in human non-small cell lung cancer (NSCLC) cells expressing wild-type p53 by increasing the level of the death domain-containing cell surface receptor Killer/DR5. In the present study, we investigated whether CD437 induced the expression of Fas (CD95/APO-1), a cell surface protein belonging to the tumor necrosis factor receptor superfamily, which induces apoptosis upon interaction with Fas ligand (FasL) or agonistic antibodies. We found that CD437 increased the level of Fas mRNA in a time- and concentration-dependent manner in NSCLC H460 cells. The increased Fas expression was also identified at the protein level. CD437 induced Fas expression in three NSCLC cell lines with wild-type p53 but not in six NSCLC cell lines containing mutant p53. Moreover, enhanced degradation of wild-type p53 protein in NSCLC cells expressing human papillomavirus-16 E6 oncoprotein blocked CD437-induced Fas expression. These results implicate the involvement of wild-type p53 in CD437-induced Fas expression in human NSCLC cells. CD437 did not change Fas mRNA stability, and actinomycin D abolished CD437-induced expression of Fas mRNA, suggesting that CD437 induces Fas expression at the transcriptional level. The combination of CD437 and FasL or CD437 and agonistic anti-Fas antibody caused synergistic induction of apoptosis. Furthermore, CD437 augmented Fas/ FasL-induced apoptosis in cell lines with wild-type p53 but not in cell lines having mutant p53, indicating that a p53-dependent mechanism is also involved in this effect. Taken together, these results demonstrate that increased Fas expression may play an important role in CD437-induced, p53-dependent apoptosis in human NSCLC cells.

Implication of multiple mechanisms in apoptosis induced by the synthetic retinoid CD437 in human prostate carcinoma cells

The synthetic retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437) induces apoptosis in several types of cancer cell. CD437 inhibited the growth of both androgen-dependent and -independent human prostate carcinoma (HPC) cells in a concentration-dependent manner by rapid induction of apoptosis. CD437 was more effective in killing androgen-independent HPC cells such as DU145 and PC-3 than the androgen-dependent LNCaP cells. The caspase inhibitors Z-VAD-FMK and Z-DEVD-FMK blocked apoptosis induced by CD437 in DU145 and LNCaP cells, in which increased caspase-3 activity and PARP cleavage were observed, but not in PC-3 cells, in which CD437 did not induce caspase-3 activation and PARP cleavage. Thus, CD437 can induce either caspase-dependent or caspase-independent apoptosis in HPC cells. CD437 increased the expression of c-Myc, c-Jun, c-Fos, and death receptors DR4, DR5 and Fas. CD437's potency in apoptosis induction in the different cell lines was correlated with its effects on the expression of oncogenes and death receptors, thus implicating these genes in CD437-induced apoptosis in HPC cells. However, the importance and contribution of each of these genes in different HPC cell lines may vary. Because CD437 induced the expression of DR4, DR5 and Fas, we examined the effects of combining CD437 and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and Fas ligand, respectively, in HPC cells. We found synergistic induction of apoptosis, highlighting the importance of the modulation of these death receptors in CD437-induced apoptosis in HPC cells. This result also suggests a potential strategy of using CD437 with TRAIL for treatment of HPC. Oncogene (2000) 19, 4513 - 4522.

Dual mechanisms of action of the retinoid CD437: nuclear retinoic acid receptor-mediated suppression of squamous differentiation and receptor-independent induction of apoptosis in UMSCC22B human head and neck squamous cell carcinoma cells

The synthetic retinoid 6-[3-(adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437), which can bind to and activate the nuclear retinoic acid receptors beta and gamma (RARbeta/gamma), is a potent inducer of apoptosis in various cancer cell lines. However, this effect was reported to be independent of RARs. In this study, we compared and contrasted the potencies and mechanisms of action of CD437 and several other receptor-selective retinoids in induction of apoptosis and modulation of squamous differentiation in UMSCC22B human head and neck squamous cell carcinoma cell line. CD437 and the structurally related retinoid CD2325 exhibited almost equal potency in inducing apoptosis, whereas several other retinoids failed to induce apoptosis. The RAR-specific pan antagonist AGN193109 failed to suppress CD437-induced apoptosis, indicating that the induction of apoptosis by CD437 was RAR-independent. c-Fos expression was induced by CD437 and CD2325 that induced apoptosis in the cell line but not by other retinoids that failed to induce apoptosis, suggesting a role for c-Fos in CD437-induced apoptosis. At low concentration (0.01 microM), CD437 shared with several other receptor-selective retinoids the ability to suppress the mRNA levels of the squamous differentiation markers Spr1, involucrin, and cytokeratin 1. This effect of CD437 could be blocked by AGN193109. We conclude that CD437 can exert its effects in UMSCC22B human human head and neck squamous cell carcinoma cells by at least two mechanisms: RAR-mediated suppression of squamous differentiation and RAR-independent induction of apoptosis.

Evidence that retinoic acid receptor beta induction by retinoids is important for tumor cell growth inhibition

Retinoic acid receptor beta (RARbeta) is thought to be involved in suppressing cell growth and tumorigenicity. Many premalignant and malignant cells exhibit a reduced RARbeta expression. However, in some of these cells (e.g. H157 human squamous cell carcinoma cells), RARbeta can be induced by retinoids (e.g. all-trans-retinoic acid, ATRA) because its promoter contains a retinoic acid response element. To examine the hypothesis that RARbeta induction is important for inhibition of cell proliferation by retinoids, we blocked ATRA-induced RARbeta expression in H157 cells using a retroviral vector harboring multiple copies of antisense RARbeta2 sequences. Antisense RARbeta-transfected cells showed not only decreased expression of ATRA-induced RARbeta protein but also reduced ATRA-induced RARE binding activity and transactivation. Importantly, all antisense RARbeta transfectants of H157 cells were less responsive than vector-transfected cells to the growth inhibitory effects of the retinoids ATRA and Ch55 in vitro. These results demonstrate that RARbeta induction may play an important role in mediating growth inhibitory effects of retinoids in cancer cells.

Identification of receptor-selective retinoids that are potent inhibitors of the growth of human head and neck squamous cell carcinoma cells

Retinoids modulate the growth and differentiation of cancer cells presumably by activating gene transcription via the nuclear retinoic acid receptor (RAR) alpha, beta, and gamma and retinoid X receptor (RXR) alpha, beta, and gamma. We analyzed the effects of 38 RAR-selective and RXR-selective retinoids on the proliferation of 10 human head and neck squamous cell carcinoma (HNSCC) cell lines. All of these cell lines expressed constitutively all of the receptor subtypes except RARbeta, which was detected in only two of them. Most of the RAR-selective retinoids inhibited the growth of HNSCC cells to varying degrees, whereas the RXR-selective retinoids showed very weak or no inhibitory effects. Three RAR antagonists suppressed growth inhibition by RAR-selective agonists, as well as by RAR/RXR panagonists such as 9-cis-retinoic acid. Combinations of RXR-selective and RAR-selective retinoids exhibited additive growth-inhibitory effects. Furthermore, we found that CD437, the most potent growth-inhibitory retinoid induced apoptosis and up-regulated the expression of several apoptosis-related genes in HNSCC cells. These results indicate that: (a) retinoid receptors are involved in the growth-inhibitory effects of retinoids; (b) RXR-RAR heterodimers rather than RXR-RXR homodimer are the major mediators of growth inhibition by retinoids in HNSCC cells; and (c) induction of apoptosis can account for one mechanism by which retinoids such as CD437 inhibit the growth of HNSCC cells. Finally, these studies identified several synthetic retinoids, which are much more effective than the natural RAs and can be good candidates for chemoprevention and therapy of head and neck cancers.

Implication of c-Myc in apoptosis induced by the retinoid CD437 in human lung carcinoma cells

The novel synthetic retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437) has been recently identified to be a potent inducer of apoptosis in human non-small cell lung carcinoma (NSCLC) cells through a nuclear retinoic acid receptor independent mechanism. To approach the mechanism by which CD437 induces apoptosis in NSCLC cells, we investigated the involvement of c-Myc in CD437-induced apoptosis. CD437 (1 microM) up-regulated the expression of c-Myc and of its downstream target genes ornithine decarboxylase (ODC) and cdc25A in all three NSCLC cell lines (i.e., H460, SK-MES-1 and H1792) used. These effects were correlated with cellular susceptibilities to induction of apoptosis by CD437. Furthermore, CD437-induced apoptosis could be blocked by the ODC inhibitor difluoromethylornithine, the caspase inhibitors Z-VAD FMK and Z-DEVD FMK, and c-Myc antisense oligodeoxynucleotide, respectively. These data indicate that c-Myc gene plays an important role in mediating CD437-induced apoptosis in human NSCLC cells.

Implication of p53 in growth arrest and apoptosis induced by the synthetic retinoid CD437 in human lung cancer cells

CD437 is a novel retinoid that can induce apoptosis in a variety of tumor cell types by an unknown mechanism. We found that CD437 up-regulated the expression of p21(WAF1/CIP1), Bax, and Killer/DR5 and induced G1 arrest and rapid apoptosis in three human non-small cell lung carcinoma cell lines with wild-type p53 but not in five cell lines with mutant p53, suggesting a role for p53 in the effects of CD437. Using H460 cells in which wild-type p53 protein was degraded by transfection of the human papillomavirus 16 E6 (HPV-16 E6) gene and H460 cells transfected with a control plasmid only, we found that CD437 increased p53, p21(WAF1/CIP1), Bax, and Killer/DR5 in the control transfectants. In contrast, the constitutive p53 protein level was suppressed, and the ability of CD437 to increase p53 and its downstream genes was compromised in E6 transfectants. In addition, CD437 induced G1 arrest and apoptosis in the control transfectants but not in the E6-transfected cells. These results indicate that p53 plays a role in CD437-induced growth inhibition and apoptosis in human non-small cell lung carcinoma cells.

Cloning and tissue expressional characterization of a full-length cDNA encoding human neuronal protein P17.3

A full-length cDNA of 595 bp was isolated from a human fetal brain cDNA library. It contains an open reading frame encoding 153 amino acids, with an 18-bp 5'UTR and a 118-bp 3'UTR in which there is an atypical polyadenylation signal (ATTAAA). The calculated molecular weight of the deduced protein is 17.3 kU. The predicted isoelectric point is 4.89. On account of its high homology to mouse neuronal protein NP15.6 (81.2% identity), the deduced protein was named neuronal protein 17.3 (NP17.3). When its secondary structure was examined by the GGBSM program of PCGENE software, it was found that 32.6 and 15.0% of its amino acids are involved in forming alpha-helices and beta-sheets, respectively. Examined with the PESTFIND program, a typical PEST region found in rapidly degraded proteins was found between residue 48 and residue 68.

Mediation of N-(4-hydoxyphenyl)retinamide-induced apoptosis in human cancer cells by different mechanisms

The induction of apoptosis by the synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) has been documented in vitro in various cancer types. A role for reactive oxygen species (ROS) in apoptosis induced by 4HPR in some cancer cells has been demonstrated recently. We studied five different human head and neck and five lung cancer cell lines to determine whether the ROS play a general role in 4HPR-induced apoptosis. We found that 4HPR induced apoptosis in all of the cell lines; however, this effect was blocked by antioxidants in only 2 of the 10 cell lines. 4HPR induced a greater than 4-fold increase in the generation of intracellular ROS in these two cell lines compared with a much lower effect in other cell lines. Furthermore, these two cell lines were most sensitive to the induction of apoptosis by 4HPR. The level of the cellular antioxidant thiol and superoxide dismutase activity were relatively lower in cells, which responded to 4HPR with a high level of ROS generation. These results indicate that although ROS can mediate 4HPR-induced apoptosis in some cells, which may have a low endogenous cellular antioxidant levels, other mechanisms exist for 4HPR-induced apoptosis. One such mechanism may involve retinoic acid receptors (RARs) because an RAR antagonist was able to block partially 4HPR-induced apoptosis. In conclusion, 4HPR-induced apoptosis involves at least three different mechanisms, which are complex and can overlap in the same cell line: (a) one mechanism involving 4HPR-induced ROS; (b) one involving RARs; and (c) at least one that does not involve ROS or RARs and remains unclear.

Mechanisms of apoptosis induced by the synthetic retinoid CD437 in human non-small cell lung carcinoma cells

The novel synthetic retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437) has been shown to induce apoptosis in various tumor cell lines including human non-small cell lung carcinoma (NSCLC) cells, which are resistant to the natural all-trans retinoic acid and to many synthetic receptor-selective retinoids. Although the mechanism of this effect was not elucidated, it was found to be independent of nuclear retinoid receptors. In the present study, we analysed the mechanisms by which CD437 induces apoptosis in two human NSCLC cell lines: H460 with wild-type p53 and H1792 with mutant p53. Both cell lines underwent apoptosis after exposure to CD437, although the cell line with wild-type p53 (H460) was more sensitive to the induction of apoptosis. CD437 increased the activity of caspase in both cell lines, however, the effect was much more pronounced in the H460 cells. The caspase inhibitors (Z-DEVD-FMK and Z-VAD-FMK) suppressed CD437-induced CPP32-like caspase activation and apoptosis in both cell lines. CD437 induced the expression of the p53 gene and its target genes, p21, Bax, and Killer/DR5, only in the H460 cells. These results suggest that CD437-induced apoptosis is more extensive in NSCLC cells that express wild-type p53, possibly due to the involvement of the p53 regulated genes Killer/DR5, and Bax although CD437 can also induce apoptosis by means of a p53-independent mechanism. Both pathways of CD437-induced apoptosis appear to involve activation of CPP32-like caspase.

Induction of apoptosis by N-(4-hydroxyphenyl)retinamide and its association with reactive oxygen species, nuclear retinoic acid receptors, and apoptosis-related genes in human prostate carcinoma cells

The synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) has been shown to induce apoptosis in various malignant cells including human prostate carcinoma cells (HPC). We examined several possible mechanisms by which 4HPR could induce apoptosis in HPC cells. 4HPR exhibited concentration- and time-dependent decrease in cell number both in androgen-dependent (LNCaP) and -independent (DU145 and PC-3) cells. The 4HPR concentrations causing 50% decrease in cell number in LNCaP, DU145, and PC-3 cultures were 0.9 +/- 0.16, 4.4 +/- 0.45, and 3.0 +/- 1.0 microM, respectively, indicating that LNCaP cells were more sensitive to 4HPR than the other cells. 4HPR-induced apoptosis in all three cell lines was evidenced by increased enzymatic labeling of DNA breaks and formation of a DNA ladder. 4HPR increased the level of reactive oxygen species, especially in LNCaP cells. 4HPR-induced apoptosis could be suppressed in LNCaP cells by antioxidant and in DU145 cells by a nuclear retinoic acid receptor-specific antagonist, suggesting the involvement of reactive oxygen species or retinoic acid receptors in mediating apoptosis induced by 4HPR in the different HPC cells. Furthermore, 4HPR modulated the expression levels of some apoptosis-related gene (p21, c-myc, and c-jun), which may also contribute to the induction of apoptosis by 4HPR in HPC cells.

Expression of skeletal muscle sarcoplasmic reticulum calcium-ATPase is reduced in rats with postinfarction heart failure

OBJECTIVE

To determine whether heart failure in rats is associated with altered expression of the skeletal muscle sarcoplasmic reticulum Ca2+-ATPase (SERCA).

METHODS

SERCA protein and mRNA were examined in the soleus muscles of eight female rats with heart failure induced by coronary artery ligation, six weeks after the procedure (mean (SEM) left ventricular end diastolic pressure 20.4 (2.2) mm Hg) and in six sham operated controls by western and northern analyses, respectively.

RESULTS

SERCA-2a isoform protein was reduced by 16% (112 000 (4000) v 134 000 (2000) arbitrary units, p < 0.001), and SERCA-2a messenger RNA was reduced by 59% (0.24 (0. 06) v 0.58 (0.02) arbitrary units, p < 0.001). Although rats with heart failure had smaller muscles (0.54 mg/g v 0.66 mg/g body weight), no difference in locomotor activity was observed.

CONCLUSIONS

These results may explain the previously documented abnormalities in calcium handling in skeletal muscle from animals with the same model of congestive heart failure, and could be responsible for the accelerated muscle fatigue characteristic of patients with heart failure.

Differential responses of normal, premalignant, and malignant human bronchial epithelial cells to receptor-selective retinoids

Using an in vitro lung carcinogenesis model consisting of normal, premalignant, and malignant human bronchial epithelial (HBE) cells, we analyzed the growth inhibitory effects of 26 novel synthetic retinoic acid receptor (RAR)- and retinoid X receptor (RXR)-selective retinoids. RAR-selective retinoids such as CD271, CD437, CD2325, and SR11364 showed potent activity in inhibiting the growth of either normal or premalignant and malignant HBE cells (IC50s mostly <1 microM) and were much more potent than RXR-selective retinoids. Nonetheless, the combination of RAR- and RXR-selective retinoids exhibited additive effects in HBE cells. As the HBE cells became progressively more malignant, they exhibited decreased or lost sensitivity to many retinoids. The activity of the RAR-selective retinoids, with the exception of the most potent retinoid, CD437, could be suppressed by an RAR panantagonist. These results suggest that: (a) RAR/RXR heterodimers play an important role in mediating the growth inhibitory effects of most retinoids in HBE cells; (b) CD437 may act through an RAR-independent pathway; (c) some of the RAR-selective retinoids may have the potential to be used in the clinic as chemopreventive and chemotherapeutic agents for lung cancer; and (d) early stages of lung carcinogenesis may be responsive targets for chemoprevention by retinoids, as opposed to later stages.

Post-infarction heart failure in the rat is associated with distinct alterations in cardiac myocyte molecular phenotype

The myocardial molecular and cellular responses to hemodynamic and other hypertrophic stimuli have been characterized extensively, but less is known of the alterations in gene expression during the evolution of heart failure following myocardial infarction, and specifically those affecting the cardiac myocytes. Therefore, the present study was undertaken to test the hypothesis that post-infarction heart failure and remodeling in the rat is associated with a distinct myocyte molecular phenotype. To address this question, hemodynamic measurements were performed in vivo; and myocytes isolated from the non-infarcted myocardium 1 day, 1 week, and 6 weeks post-coronary artery ligation in post-infarct rats and sham controls. Myocyte size, mRNA levels for immediate early genes, contractile proteins, and sarcoplasmic reticulum Ca2+-ATPase (SERCA) and phospholamban were assayed by Northern analyses, and SERCA and phospholamban proteins were examined by Western blotting. Hemodynamic evidence of heart failure was present at all post-infarct time points. Myocyte size was increased significantly at 6 weeks. c-myc expression was increased at 1 day and 1 week in the infarcted rats, but returned to baseline by 6 weeks. Atrial natriuretic peptide and VEGF mRNAs were elevated at 1 and 6 weeks. Both beta-myosin heavy chain and skeletal alpha-actin expression were increased at all post-MI time points. In contrast, neither changes in the expression of the calcium-handling proteins (SERCA and phospholamban) were not observed, nor was there a change in TGFbeta1 or TGFbeta3. These results demonstrate that in rats with post-MI heart failure, there was an immediate induction of the fetal/embryonic transcriptional gene program which preceded myocyte hypertrophy and appeared to persist longer than in pressure-overload models. In further contrast to pressure-overload, expression of sarcoplasmic reticulum Ca2+-ATPase and phospholamban, was not altered despite a comparable degree of cellular hypertrophy and more severe hemodynamic decompensation. These findings suggest that there may be important differences in the regulatory mechanisms underlying these two forms of myocardial hypertrophy and heart failure.

Cytokine expression increases in nonmyocytes from rats with postinfarction heart failure

Growing evidence suggests that cardiac nonmyocyte cells may play an important regulatory role in the response to myocardial overload and injury via altered expression of paracrine products, such as cytokines and growth factors, but information concerning the cell-specific changes in the expression of these substances in heart-failure models is limited. Therefore, cardiac nonmyocytes were isolated from rats 1 day and 1 and 6 wk after left coronary artery ligation with resulting hemodynamic evidence of heart failure and in sham-operated control animals. mRNAs for tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-6, transforming growth factors (TGF)-beta1 and TGF-beta3, and type I and type III collagen were measured by Northern analyses. The temporal and quantitative relationships between the expression of these cytokines and collagen and myocyte hypertrophy were determined. mRNA expression of IL-1beta was increased by 1.3-fold at 1 day and 1 wk, and expression of TNF-alpha, IL-1beta, IL-6, TGF-beta1, and TGF-beta3 were increased by 1.4- to 2.1-fold at the 1-wk time point before returning toward baseline at 6 wk. There were significant correlations between the expression of these cytokines and the expression of types I and III collagen, which also peaked at 1 wk. Myocyte hypertrophy was seen first at 6 wk. These observations are consistent with a hypothesis that nonmyocyte cells play a regulatory role in the extracellular matrix changes during postinfarction remodeling and highlight the importance of examining cell-specific changes in gene expression and elucidating the role of cell-to-cell interactions within the myocardium.

Induction of apoptosis in human non-small cell lung carcinoma cells by the novel synthetic retinoid CD437

Retinoids are promising agents for the prevention and treatment of several human malignancies including lung cancer. However, many lung cancer cell lines are resistant to the growth inhibitory effects of all-trans-retinoic acid (ATRA). Recently, we found that a new synthetic retinoid, 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437), which binds selectively to nuclear RA receptor gamma, was the most effective inhibitor of the growth of human non-small cell lung carcinoma (NSCLC) cells among 37 retinoids tested. After a 4-day treatment with CD437 the growth of 8 NSCLC cell lines was inhibited with an IC50 ranging from 0.13 to 0.53 microM. In contrast, ATRA failed to inhibit the growth of any of these cell lines by more than 43% after a 7-day treatment even at 10 microM. The presence of detached rounded cells in treated cultures indicated that CD437 may induce apoptosis. Indeed, this was confirmed by the presence of 20-57% cells with a sub-G1 DNA content and by an enzyme-linked immunosorbent assay (ELISA) of apoptosis. Two retinoids, CD2366 and CD2665, which are antagonists of nuclear retinoid receptor activation, failed to inhibit the effect of CD437 on the growth of the NSCLC cell lines. CD437 failed to suppress the transcriptional activation of the activator protein-1 (AP-1) reporter. These results demonstrate that CD437 can induce apoptosis in NSCLC cells that are resistant to ATRA and that this effect is mediated by a mechanism that may be independent of transactivation of retinoid receptors or transrepression of AP-1.

Differential effects of synthetic nuclear retinoid receptor-selective retinoids on the growth of human non-small cell lung carcinoma cells

Retinoids are promising agents for cancer chemoprevention and therapy. Nuclear retinoic acid receptors (RARs; RARalpha, -beta, and -gamma) and retinoid X receptors (RXRs; RXRalpha, -beta, and -gamma) are thought to mediate most of retinoids' effects on cell growth and differentiation. Because the majority of human non-small cell lung carcinoma (NSCLC) cell lines are resistant to all-trans-retinoic acid, we searched for more potent retinoids. Therefore, we examined the effects of 37 natural and synthetic retinoids that exhibit specific binding to and transactivation of individual RARs or RXRs on the proliferation of eight human NSCLC cell lines. All of these cells expressed mRNAs of the three RXRs; however, they expressed varying levels of RARalpha and RARgamma, and only three of the eight cell lines expressed RARbeta mRNA. Cellular retinoic acid-binding proteins (CRABPs) I and II were detected in one and three of the eight cell lines, respectively. Only 8 of the 37 retinoids exhibited growth-inhibitory activity (IC50, < 10 microM) against at least two of the eight NSCLC cell lines. The active retinoids included one (TD550) of five RARalpha-selective, one (Ch55) of three RARbeta-selective, three (CD437, CD2325, and SR11364) of six RARgamma-selective, and one (CD271) of four RARbeta/gamma-selective retinoids. The potency of these retinoids was low (IC50, > 1 microM), except for CD437, which was very potent (IC50, 0.1-0.5 microM). The six RXR-selective retinoids were mostly inactive even at 10 microM. However, combinations of RAR-selective and RXR-selective retinoids exhibited additive effects. There appeared to be no simple correlation among the histological type of the NSCLC (adeno- or squamous), the levels of nuclear receptors or CRABPs, and the response of the cells to the growth-inhibitory effects of retinoids. Nevertheless, in contrast with former studies with natural retinoids, these results suggest that several synthetic retinoids do exhibit inhibitory activity against NSCLC cells, and some of them may be useful clinically.

Heart failure in rats causes changes in skeletal muscle morphology and gene expression that are not explained by reduced activity

In patients with congestive heart failure, skeletal muscle is characterized by a smaller proportion of slow-twitch oxidative fibers and reduced oxidative enzyme activity. However, whether these changes result from disuse or occur as a direct consequence of heart failure is unresolved. To address this issue, 18 rats with heart failure 8 weeks after left coronary artery ligation and 13 sham-operated control rats underwent quantification of locomotor activity by a photocell activation technique, measurements of hemodynamics and infarct size, histochemical and morphological analyses of the soleus and plantaris muscles, and Northern analyses of muscle contractile protein and oxidative enzyme mRNA expression. Although the rats with heart failure had elevated left ventricular end-diastolic pressures (24.1 +/- 2.6 mm Hg) and a mean infarct size of 35.1 +/- 4.1%, activity levels were similar to those found in the sham-operated rats (3849 +/- 304 versus 3526 +/- 130 counts per hour). With heart failure, there was a significant reduction of type I fibers in the soleus muscle and type IIa fibers in the plantaris muscle, with corresponding increases in intermediate staining of type IIab fibers in both muscles. This was associated with a 17% decrease in citrate synthase activity in both the soleus and plantaris muscles (26.2 +/- 1.6 versus 30.7 +/- 3.4 and 29.1 +/- 2.4 versus 35.7 +/- 3.4 mumol/L per minute per gram, respectively [P < .05]). In the soleus muscle, mRNA for both beta-myosin heavy chains and cytochrome C oxidase III (normalized to 18S RNA) was reduced (0.27 +/- 0.02 versus 0.65 +/- 0.02 and 0.23 +/- 0.04 versus 0.64 +/- 0.02 U), whereas the messages for IIx and IIb myosin heavy chains were increased. A similar decrease in messages for cytochrome oxidase and the primary myosin isoform was observed in the plantaris muscle. Both soleus beta-myosin heavy chain and cytochrome C oxidase expression show significant inverse relationships to left ventricular end-diastolic pressure and infarct size. In contrast, there was no relationship between either beta-myosin heavy chain or cytochrome C oxidase expression and locomotor activity. These results indicate that in rats heart failure produces changes in skeletal muscle gene expression at the pretranslational level that cannot be explained by inactivity.