Two-stage hybrid Ivor-Lewis esophagectomy as surgical strategy to reduce postoperative morbidity for high-risk patients.

BACKGROUND: Ivor-Lewis esophagectomy (ILE) is the standard surgical care for esophageal cancer patients but postoperative morbidity impairs quality of life and reduces long-term oncological outcome. Two-stage ILE separating the abdominal and thoracic phase into two distinct surgical procedures has proven to enhance microcirculation of the gastric conduit and therefore most likely reduces complications. However, two-stage ILE has not been evaluated systematically in selected groups of patients scheduled for this procedure. This investigation aims to demonstrate the feasibility of two-stage ILE in high-risk patients. PATIENTS AND METHODS: In this retrospective analysis of data obtained from a prospective database, a consecutive series of 275 hybrid ILE (hILE) were included. Patients were divided into two groups based on one- or two-stage hILE. Postoperative complications were assessed according to ECCG (Esophageal Complication Consensus Group) criteria and compared using the Clavien-Dindo score. Indication for two-stage esophagectomy was classified as pre- or intraoperative decision. RESULTS: 34 out of 275 patients (12.7%) underwent two-stage hILE. Patients of the two-stage group were significantly older. In 21 of 34 patients (61.8%) the decision for a two-stage procedure was made prior to esophagectomy, in 13 (38.2%) patients intraoperatively after completion of the laparoscopic gastric mobilization. The most frequent preoperative reason to select the two-stage procedure was a stenosis of the coeliac trunc and superior mesenteric artery (n = 10). The predominant cause for an intraoperative change of strategy was a laparoscopically diagnosed hepatic fibrosis/cirrhosis (n = 5).Overall morbidity and major' complications (CD > IIIa) were comparable for both groups (11.7% in both groups). The overall anastomotic leak rate was 12.4% and was non-significant lower for the two-stage procedure. CONCLUSION: Two-stage hILE is a feasible concept to individualize the surgical treatment of patients with well-defined clinical risk factors for postoperative morbidity. It can also be applied after completion of the abdominal phase of IL esophagectomy without compromising the patient safety.

Simultaneous laryngopharyngeal pH monitoring (Restech) and conventional esophageal pH monitoring-correlation using a large patient cohort of more than 100 patients with suspected gastroesophageal reflux disease.

24-hour esophageal pH-metry is not designed to detect laryngopharyngeal reflux (LPR). The new laryngopharyngeal pH-monitoring system (Restech) may detect LPR better. There is no established correlation between these two techniques as only small case series exist. The aim of this study is to examine the correlation between the two techniques with a large patient cohort. All patients received a complete diagnostic workup for gastroesophageal reflux including symptom evaluation, endoscopy, 24-hour pH-metry, high resolution manometry, and Restech. Consecutive patients with suspected gastroesophageal reflux and disease-related extra-esophageal symptoms were evaluated using 24-hour laryngopharyngeal and concomitant esophageal pH-monitoring. Subsequently, the relationship between the two techniques was evaluated subdividing the different reflux scenarios into four groups. A total of 101 patients from December 2013 to February 2017 were included. All patients presented extra-esophageal symptoms such as cough, hoarseness, asthma symptoms, and globus sensation. Classical reflux symptoms such as heartburn (71%), regurgitation (60%), retrosternal pain (54%), and dysphagia (32%) were also present. Esophageal 24-hour pH-metry was positive in 66 patients (65%) with a mean DeMeester Score of 66.7 [15-292]. Four different reflux scenarios were detected (group A-D): in 39% of patients with abnormal esophageal pH-metry, Restech evaluation was normal (group A, n = 26, mean DeMeester-score = 57.9 [15-255], mean Ryan score = 2.6 [2-8]). In 23% of patients with normal pH-metry (n = 8, group B), Restech evaluation was abnormal (mean DeMeester-score 10.5 [5-13], mean Ryan score 63.5 [27-84]). The remaining groups C and D showed corresponding results. Restech evaluation was positive in 48% of cases in this highly selective patient cohort. As demonstrated by four reflux scenarios, esophageal pH-metry and Restech do not necessarily need to correspond. Especially in patients with borderline abnormal 24-hour pH-metry, Restech may help to support the decision for or against laparoscopic anti-reflux surgery.

Endoscopic and histopathologic reflux-associated mucosal damage in the remnant esophagus following transthoracic esophagectomy for cancer-5-year long-term follow-up.

Gastroesophageal reflux is a common problem following esophagectomy and reconstruction with gastric interposition. Despite a routine prescription of proton pump inhibitors, reflux-associated mucosal damage in the remnant esophagus is frequently observed. Purpose of this study is to evaluate mucosal damage in the esophageal remnant during long-term follow-up and to compare the prevalence of this damage between the subgroups of esophageal squamous cell and adenocarcinoma. All patients undergoing transthoracic Ivor-Lewis esophagectomy were prospectively entered in our IRB approved database. All patients underwent a routine check-up program with yearly surveillance endoscopies following esophagectomy. Only patients with a complete follow-up were included into this study. Endoscopic and histopathologic mucosal changes of the remnant esophagus were analyzed in close intervals. A total of 50 patients met the inclusion criteria, consisting of 31 adenocarcinomas (AC) and 19 squamous cell carcinomas (SCC). Mucosal damage was already seen 1 year after surgery in 20 patients macroscopically (43%) and in 21 patients microscopically (45%). At 5-year follow-up the prevalence for macroscopic and microscopic damage was 55% and 60%, respectively. The prevalence of mucosal damage was higher in AC patients than in SCC patients (1y-FU: 51% [AC] vs. 28% [SCC]; 5y-FU: 68% [AC] vs. 35% [SCC], P < 0.05). Newly acquired Barrett's esophagus was seen in 10 patients (20%) with two of those patients (20%) showing histopathologic proof of neoplasia. This study shows a high prevalence of reflux-associated mucosal damage in the remnant esophagus one year out of surgery and only a moderate increase in prevalence in the following years. Mucosal damage was more frequently seen in AC patients and the occurrence of de-novo Barrett's esophagus and de-novo neoplasia was high. Endoscopic surveillance with targeted biopsies seems to be an indispensable tool to follow patients after esophagectomy appropriately.

Management of Tracheo- or Bronchoesophageal Fistula After Ivor-Lewis Esophagectomy.

BACKGROUND: The development of tracheo- or bronchoesophageal fistula (TBF) after Ivor-Lewis esophagectomy remains to be a rare complication associated with a high mortality rate. METHODS: In this retrospective study, the charts of patients with TBF after esophagectomy were analyzed in terms of individual patient characteristics, esophagotracheal complications, respiratory function, management, and outcome. RESULTS: Between January 2000 and December 2014, 1204 patients underwent Ivor-Lewis esophagectomy for esophageal cancer; 13 patients (1.1 %) developed a TBF. In all 13 patients, a concomitant leakage of the intrathoracic esophagogastrostomy was evident, either prior to diagnosis of TBF (metachronous TBF) or simultaneously (synchronous TBF). TBF was predominantly located in the left main bronchus (n = 6, 46.1 %) or trachea (n = 5, 38.5 %). Management of TBF included re-thoracotomy (n = 7), interventional endoscopic (n = 10) or bronchoscopic therapy (n = 4). In the majority of patients (n = 8), management consisted of two subsequent treatment modalities. In 3 out of four patients, TBF was successfully treated by endoscopic stenting only. Five patients (38.5 %) died following a septic course with multiple organ failure. CONCLUSIONS: The development of TBF after Ivor-Lewis esophagectomy is always combined with anastomotic leakage of the esophagogastrostomy. Treatment options primarily depend on the vascularization of the gastric conduit, the severity of the concomitant aspiration pneumonia, and the volume of the air leakage.

Preoperative airway colonization prior to transthoracic esophagectomy predicts postoperative pulmonary complications.

PURPOSE: Respiratory complications are responsible to a high degree for postoperative morbidity and mortality after Ivor-Lewis esophagectomy. The etiology of respiratory failure is known to be multifactorial with preoperative impaired lung function being the most important one. The aim of this study was to investigate the correlation between preoperative airway colonization (PAC) and postoperative respiratory complications. METHODS: In this observational study, 64 patients with esophageal cancer were included. All patients underwent Ivor-Lewis esophagectomy with laparoscopic or open gastric mobilization. After induction of anesthesia and intubation with a double-lumen tube, bronchial exudate was collected by random endoluminal suction for further microbiological work-up. Length of postoperative mechanical ventilation (<24 h, 24-72 h, >72 h), re-intubation, and tracheostomy were recorded as primary and secondary study endpoints. RESULTS: In 13 of 64 study patients (20.3 %), pathological colonization of the bronchial airways could be proved prior to esophagectomy. Haemophilus species was the most frequently identified pathogen. PAC was associated with a longer history of smoking (p = 0.025), a lower preoperative forced expiratory volume (FEV1, p = 0.009) or vital capacity (VC, p = 0.038), a prolonged postoperative mechanical ventilation (p < 0.001), and a higher frequency of re-intubation (p < 0.001) and tracheostomy (p = 0.017). In the multivariate analysis, PAC was identified as an independent predictor of respiratory failure (hazard ratio 11.4, 95 % confidence interval 2.6-54, p = 0.002). Mortality in the PAC group was 30.8 % compared to 0 % in patients without PAC (p < 0.0001). CONCLUSION: PAC is a significant risk factor for postoperative respiratory failure. A routine bronchoscopy and bronchoalveolar lavage as part of preoperative management prior to esophagectomy need to be discussed.

[Perforations near the cardia in benign diseases]. / Kardianahe Perforation bei gutartigen Erkrankungen.

Esophageal perforations nearby the cardia are a clinical disorder of various causes. Perforations occur most often following diagnostic or interventional endoscopy but spontaneous perforations (Boerhaave syndrome) are less frequent. Due to the heterogeneous etiology there is a broad range of therapeutic options. In most cases the esophageal perforation site can be covered by an endoscopic stent. Recent endoscopic procedures are the intraluminal application of an endoscopic vacuum-assisted closure system (endo-VAC) or clipping of the esophageal defect. Surgical procedures include direct suturing with external coverage of the defect or transhiatal blunt dissection of the esophagus without primary reconstruction. All endoscopic and surgical procedures often require an additional drainage of the mediastinum and if necessary of the thoracic and abdominal cavities. The clinical presentation ranges from a simple perforation without concomitant esophageal pathology to a defect of considerable length with pleural perforation and associated septic multiple organ failure. The severity of the septic course is the crucial parameter for the choice of the procedure. An early multiple organ failure indicates an insufficient drainage of the septic focus and is indicative for surgical resection. The overall mortality is given as 12 % in the current literature and primarily depends on the localization and the etiology of the perforation. The highest mortality rates are observed with Boerhaave syndrome. The most important prognostic variable is the time interval between perforation and initiation of therapy whereby the mortality rises up to 20 % if the interval exceeds 24 h. Due to the complex therapy and the poor prognosis esophageal perforations should be treated in specialized centers.

Management of upper intestinal leaks using an endoscopic vacuum-assisted closure system (E-VAC).

BACKGROUND: Esophageal perforations and postoperative leakage of esophagogastrostomy are considered to be life-threatening conditions due to the development of mediastinitis and consecutive sepsis. Vacuum-assisted closure (VAC), a well-established treatment method for superficial infected wounds, is based on a negative pressure applied to the wound via a vacuum-sealed sponge. Endoluminal VAC (E-VAC) therapy is a novel method, and experience with its esophageal application is limited. METHODS: This retrospective study summarizes the experience of a center with a high volume of upper gastrointestinal surgery using E-VAC therapy for patients with leakages of the esophagus. The study investigated 14 patients who had esophageal defects treated with E-VAC. Three patients had a spontaneous defect; two patients had an iatrogenic defect; and nine patients had a postoperative esophageal defect. RESULTS: The average duration of application was 12.1 days, and an average of 3.9 E-VAC systems were used. For 6 of the 14 patients, E-VAC therapy was combined with the placement of self-expanding metal stents. Complete restoration of the esophageal defect was achieved in 12 (86 %) of the 14 patients. Two patients died due to prolonged sepsis. CONCLUSION: This report demonstrates that E-VAC therapy adds an additional treatment option for partial esophageal wall defects. The combination of E-VAC treatment and endoscopic stenting is a successful novel procedure for achieving a high closure rate.

[Complications and management of complications in oesophageal surgery]. / Komplikationen und Komplikationsmanagement in der Ösophaguschirurgie.

BACKGROUND: Prevention, early recognition and an adequate management of perioperative complications in resectional oesophageal surgery are the keys to an increased safety of these complex procedures. RECOGNITION, DIAGNOSTICS, MANAGEMENT AND TREATMENT: Preoperative registration and - if required - pretreatment of specific risk factors can considerably decrease the complication rate. The precise implementation of significant preoperative score systems in patients with high operative risk can lead to a negative risk-benefit consideration concerning the indication for an operation. The patients will then be assigned to an alternative treatment process. Anastomotic leakage is the most frequent technical-surgical complication. A precise suturing technique with the prevention of tension and the avoidance of reduction of perfusion of the conduit (stomach, colon, small intestine) can reduce the rate of such insufficiencies. The most frequent non-surgical complication is postoperative pneumonia, which can be avoided or combated through effective pain-relieving therapy like peridural anaesthesia and specific techniques of postoperative ventilation. It is of vital importance to identify, at the earliest possible timepoint, complications that might emerge after the operation. The occurrence of postoperative tachyarrhythmia has proven to be a frequent and early indicator of such complications. The treatment of complications after oesophageal resections includes adequate conservative, interventional, e. g., endoscopic placement of a stent in cases of covered insufficiency of the suture line, and operative procedures like reoperation in cases of uncovered leakage with pleural connection. All the other surgical complications like haemorrhage, tracheobronchial leak-ages or chylothorax are rarely seen and demand specific therapeutic procedures. CONCLUSION: It is not only the surgery that determines a high or low complication rate in oesophageal resectional procedures. It has clearly been proved that interdisciplinary management of complications after oesophagectomy is much more effective in high-volume centres, leading to a lower mortality, than in surgical departments with a lower case rate and thus with less experience in such complex operations.

Circular stapled pyloroplasty: a fast and effective technique for pyloric disruption during esophagectomy with gastric pull-up.

The necessity of pyloroplasty after esophagectomy and gastric pull-up is debated. Disadvantages of a standard pyloroplasty include the potential for leak, shortening of the length of the graft, and complexity when done during a minimally invasive procedure. The aim of this study is to report our experience with a novel internal pyloroplasty technique using a circular stapler (CS pyloroplasty), which is applicable for both laparoscopic and open esophagectomy. The records of all patients who underwent an esophagectomy with gastric pull-up and pyloroplasty between 2002 and 2007 were reviewed. The CS pyloroplasty was performed through a lesser curve gastrotomy with a 21-mm CS, while the standard pyloroplasty entailed a longitudinal full thickness incision through the pylorus with mucosal closure in the same direction and a Graham patch. A CS pyloroplasty was performed in 144 and a standard pyloroplasty in 133 patients. The median patient age was 66years, and the median follow-up was 17months, and was similar for both types of pyloroplasty. Routine postoperative videoesophagram was significantly more likely to show a delay in contrast transit through the pylorus after standard pyloroplasty (16% standard vs. 8% CS pyloroplasty, P= 0.03). Significantly more patients had postoperative endoscopy after standard pyloroplasty (40% standard vs. 24% CS pyloroplasty, P= 0.004), but the frequency of pyloric dilatation was similar. There were no leaks with either technique. A circular stapled pyloroplasty is as efficacious as a standard pyloroplasty after esophagectomy with gastric pull-up. Potential advantages include the ease and simplicity of the procedure along with virtually no risk of a leak and no graft shortening. The technique is amenable to both open and minimally invasive procedures.

Lack of prognostic significance of serum DNA methylation of DAPK, MGMT, and GSTPI in patients with non-small cell lung cancer.

BACKGROUND AND OBJECTIVES: To further improve the screening, diagnosis and therapy of patients with non-small cell lung cancer (NSCLC) additional diagnostic tools are desperately warranted. Aim of this study was to investigate the potential of the DNA methylation of DAPK, MGMT, and GSTPI in serum of patients with NSCLC as a prognostic molecular marker in this disease. METHODS: Seventy-six patients with NSCLC were included in this study. The analysis of DNA methylation in serum of patients was performed on pre-operative samples. Following DNA isolation and bisulfite-treatment, DNA methylation was analyzed by quantitative-methylation-specific real-time PCR with beta-actin as the internal reference gene. RESULTS: DNA methylation was detectable with following frequencies: DAPK 68.4%, MGMT 7.9%, GSTPI 0%. There were no associations between DNA methylation status and histology, tumor stage, grading or gender detectable. With a mean follow-up of 19.7 months the median survival was 26.3 months. There were no associations between the status of DNA methylation in patient's serum and prognosis detectable. CONCLUSION: The analysis of DNA methylation in serum of patients with NSCLC by quantitative-methylation-specific real-time PCR is technically feasible. Although our results suggest quantification of DNA methylation in serum not of prognostic significance in this disease, further studies are warranted to determine the future potential of this molecular approach.

A new technique for measurement of pharyngeal pH: normal values and discriminating pH threshold.

INTRODUCTION: Identifying gastroesophageal reflux disease as the cause of respiratory and laryngeal complaints is difficult and depends largely on the measurements of increased acid exposure in the upper esophagus or ideally the pharynx. The current method of measuring pharyngeal pH environment is inaccurate and problematic due to artifacts. A newly designed pharyngeal pH probe to avoid these artifacts has been introduced. The aim of this study was to use this probe to measure the pharyngeal pH environment in normal subjects and establish pH thresholds to identify abnormality. METHODS: Asymptomatic volunteers were studied to define the normal pharyngeal pH environment. All subjects underwent esophagram, esophageal manometry, upper and lower esophageal pH monitoring with a dual-channel pH catheter and pharyngeal pH monitoring with the new probe. Analyses were performed at 0.5 pH intervals between pH 4 and 6.5 to identify the best discriminating pH threshold and calculate a composite pH score to identify an abnormal pH environment. RESULTS: The study population consisted of 55 normal subjects. The pattern of pharyngeal pH environment was significantly different in the upright and supine periods and required different thresholds. The calculated discriminatory pH threshold was 5.5 for upright and 5.0 for supine periods. The 95th percentile values for the composite score were 9.4 for upright and 6.8 for supine. CONCLUSION: A new pharyngeal pH probe which detects aerosolized and liquid acid overcomes the artifacts that occur in measuring pharyngeal pH with existing catheters. Discriminating pH thresholds were selected and normal values defined to identify patients with an abnormal pharyngeal pH environment.

Recurrence of intramucosal esophageal adenocarcinoma arising in a former esophagostomy site: a unique case report.

A 75-year-old male with a long history of gastroesophageal reflux symptoms developed adenocarcinoma proximally within a long segment of Barrett's esophagus. He was taken for esophagectomy and gastric pull-up, but intraoperatively, he was found to have a marginal blood supply in the gastric tube. A temporary left-sided esophagostomy was created with the gastric tube sutured to the left sternocleidomastoid muscle in the neck. Pathology showed an intramucosal adenocarcinoma, limited to the muscularis mucosa with surrounding high-grade dysplasia and intestinal metaplasia. The proximal esophageal margin showed no tumor cells, but there was low-grade dysplasia within Barrett's esophagus. He was reconstructed after several months, and 2 years after reconstruction, the patient noticed a nodule at the former esophagostomy site. Biopsy revealed an implant metastasis of esophageal adenocarcinoma. Here, we review the literature and discuss the possible etiology.

[Symptoms in patients with adenocarcinoma of the esophagus]. / Refluxanamnese von Patienten mit Adenokarzinom der Speiseröhre.

INTRODUCTION: Gastroesophageal reflux (GER) is the main risk factor for the development of adenocarcinoma of the esophagus (AC). The aim of our study was to evaluate symptoms of patients with AC to identify those patients with a high risk for this tumour. PATIENTS AND METHODS: 117 consecutive patients with known AC were included. Prospectively all patients were interviewed with a standardised questionnaire comprising 120 items: social status, other diseases, risk factors, therapy of the GERD and, as a main part: current symptoms and those experienced at earlier times. RESULTS: 85 % of the patients had often or sometimes reflux symptoms. 46 % of the patients with reflux symptoms had such symptoms daily. The median time span for this symptom was 20 years with a range from 1 year to 50 years. In 21 % of the patients the reflux symptoms stopped (median) three years (range two months -- 30 years) before the diagnosis of the carcinoma. Only 55 % of all patients had one or more esophago-gastroscopy examinations before the diagnosis of AC. These patients showed significantly more often earlier tumour stages than those patients without an endoscopy before diagnosis. Heartburn was treated with medication in 78 % of the patients (67 % of all patients). No patient had previously undergone antireflux surgery. CONCLUSIONS: 15 % of the patients with adenocarcinoma of the esophagus show no, and in addition 25 % only discrete, heartburn; 1. an endoscopy due to heartburn was done in half of all cases, and 2. the medications do not fulfil the therapeutic standard; 3.patients with endoscopy had significantly more frequently an earlier tumour stage.

[Preoperative colonoscopy before esophagectomy and reconstruction with gastric interposition]. / Präoperative Koloskopie vor Magenhochzug Ist sie eine notwendige Untersuchung vor Osophagektomie und Rekonstruktion durch Mageninterponat?

INTRODUCTION: The standard treatment of esophageal carcinoma is esophagectomy and reconstruction with gastric interposition. In many centers, preoperative colonoscopy is routinely performed in order to exclude any significant colonic pathology. This is important in case of the intraoperative necessity to use a colon interposition due to gastric pathology, anatomical variation, or injury of gastric vascularization. PATIENTS AND METHODS: Two hundred twenty-eight consecutive patients with esophageal carcinoma (adenocarcinoma 102, squamous cell carcinoma 126) who underwent esophagectomy were included in this study. Of them, 171 (75%) had preoperative colonoscopy. Reconstruction was done by gastric tube in 219 and colon interposition in nine. RESULTS: Intraoperative conversion to colon interposition was necessary in none of the 219 patients with intended reconstruction by a gastric conduit. In two of 171 patients (1.2%), preoperative colonoscopy revealed pT1 adenocarcinomas of the colon which were completely removed by endoscopy, and a total of 62 adenomas were histopathologically diagnosed. Fifty-three patients (31%) had endoscopic evidence of asymptomatic diverticulosis. No complications were observed after colonoscopy. CONCLUSION: Preoperative colonoscopy prior to esophagectomy and intended gastric tube formation appears unnecessary from the surgical point of view, as intraoperative conversion to a colon interposition is rare. The rate of colon adenomas or carcinomas was not increased in patients with adeno- or squamous cell carcinoma of the esophagus than in an age-matched, normal population.

Postoperative recovery of microcirculation after gastric tube formation.

BACKGROUND AND AIMS: The formation of a gastric tube is associated with partial devascularisation of the stomach and impaired tissue perfusion in the anastomotic region. The aim of the study was to gain data on the time interval of microcirculatory recovery of the normal gastric conduit. PATIENTS AND METHODS: Twenty-nine out of 49 consecutive patients who had undergone oesophagectomy and reconstruction with a gastric tube and intrathoracic oesophagogastrostomy were selected. Inclusion criterion was an uncomplicated postoperative course. After the patients' admission to ICU, continuous measurement of mucosal pCO(2) (pCO(2)I) was commenced, with the use of recirculating gas analysis with a TONOCAP device. pCO(2)I values (in mmHg and kPa) were recorded hourly and related to the arterial pCO(2) (DeltapCO(2) = pCO(2)I - pCO(2)a). In addition, mean arterial pressure (MAP), cardiac output (CO) and systemic vascular resistance (SVR) were measured by pulse contour analysis. RESULTS: pCO(2)I was monitored over an average period of 79 h (total 2,288 measurements). The mean DeltapCO(2) before extubation was 12.4 mmHg (1.7 kPa) +/- 8.7 SD (1.2 kPa). After extubation, there was an increase in DeltapCO(2) values in all 29 patients. The peak DeltapCO(2) of 27.4 mmHg (3.7 kPa) +/- 12.6 SD (1.7 kPa) was observed 18 h after extubation. This was followed by a steady decline in DeltapCO(2) values that almost reached baseline DeltapCO(2) values after 4 days of monitoring. Changes in DeltapCO(2) did not correlate with changes in MAP, CO and SVR. CONCLUSIONS: High levels of pCO(2)I indicate an impaired postoperative microcirculation in normal gastric tubes. After initial deterioration, gastric microcirculation takes approximately 4 days to recovery. These data are important for the implementation of ischaemic conditioning prior to gastric tube formation and gastric pull-up.

Differential recruitment of the mammalian mediator subunit TRAP220 by estrogen receptors ERalpha and ERbeta.

Estrogen receptors (ERs) associate with distinct transcriptional coactivators to mediate activation of target genes in response to estrogens. Previous work has provided multiple evidence for a critical role of p160 coactivators and associated histone acetyltransferases in estrogen signaling. In contrast, the involvement of the mammalian mediator complex remains to be established. Further, although the two subtypes ERalpha and ERbeta appear to be similar in regard to principles of LXXLL-mediated coactivator binding to the AF-2 activation domain, there are indications that the context-dependent transcriptional activation profiles of the two ERs can be quite distinct. Potentially, this could be attributed to differences with regard to coregulator recruitment. We have here studied the interactions of the nuclear receptor-binding subunit of the mammalian mediator complex, referred to as TRAP220, with ERalpha and ERbeta. In comparison to the p160 coactivator TIF2, we find that TRAP220 displays ERbeta preference. Here, we show that this is a feature of the binding specificity of the TRAP220 LXXLL motifs and demonstrate that the ER subtype-specific F-domain influences TRAP220 interaction. Such differences with regard to coactivator recruitment indicate that the relative importance of individual coregulators in estrogen signaling could depend on the dominant ER subtype.

Coincidence of nutritional habits and esophageal cancer in Germany.

INTRODUCTION: The incidence rates for adenocarcinoma (AC) of the esophagus have risen rapidly in Western nations, whereas the incidence rates for esophageal squamous cell carcinoma (SCC) have remained nearly stable. There are studies about body mass index, smoking, alcohol, and development of AC or SCC. The aim of this study was to evaluate differences in nutritional habits of patients with AC or SCC compared with the population in Cologne. PATIENTS AND METHODS: From January 1, 1997 to December 31, 1998, 85 patients with esophageal cancer (SCC n = 45, AC n = 40) were interviewed about their nutritional habits using a computerized program (EBIS). By random sample, 100 citizens of Cologne who were similar of age, residence, and nationality were chosen as healthy control group (CG) and were also interviewed with EBIS. RESULTS: The known risk factors, alcohol and tobacco for SCC as well as alcohol and a high body mass index for AC, were confirmed in this study. The CG had a higher daily intake of calcium, magnesium and iron compared to patients with esophageal cancer (p < 0.05). In addition, the tumor group had a significant lower daily supply of carbohydrates, fruits, and dietary fiber (p < 0.001). About 80% of the patients ate more than 100 g meat/day in comparison to 50% of participants in the CG. Patients with AC consumed more magnesium, milk, and animal protein than patients with SCC or the participants of the CG. CONCLUSION: There are differences in nutrition between healthy controls and patients with esophageal cancer and between patients with SCC and AC. Patients with cancer of the esophagus had a nutritonal deficit in fresh fruit, vegetables, dietary fiber, and carbohydrates. Compared with the other groups, patients with AC had a higher intake of protein, fat, and milk.

The Hairy and Enhancer of Split homologue-1 (HES-1) mediates the proliferative effect of 17beta-estradiol on breast cancer cell lines.

The mechanism behind hormone dependent growth of breast cancer is presently not well understood. We show that the HES-1 protein level in the breast cancer cell lines T47D and MCF-7 is down regulated by 17beta-estradiol treatment. This regulation could be reversed by addition of the anti-estrogens 4OH tamoxifen, raloxifen and Imperial Chemical Industries (ICI) 182,780. In T47D cells with inducible exogenous HES-1 expression, induced expression of HES-1 protein prevented the proliferative effect of 17beta-estradiol and subsequent up regulation of proliferating cell nuclear antigen (PCNA). An inverse correlation between the HES-1 and PCNA protein levels respectively was found in colon cancer cell lines. These findings point to a potential role of HES-1 as a tumor suppressor in epithelial cells, and as a mediator of 17beta-estradiols proliferative effect on breast cancer cells.

Competition between thyroid hormone receptor-associated protein (TRAP) 220 and transcriptional intermediary factor (TIF) 2 for binding to nuclear receptors. Implications for the recruitment of TRAP and p160 coactivator complexes.

Transcriptional activation by nuclear receptors (NRs) involves the concerted action of coactivators, chromatin components, and the basal transcription machinery. Crucial NR coactivators, which target primarily the conserved ligand-regulated activation (AF-2) domain, include p160 family members, such as TIF2, as well as p160-associated coactivators, such as CBP/p300. Because these coactivators possess intrinsic histone acetyltransferase activity, they are believed to function mainly by regulating chromatin-dependent transcriptional activation. Recent evidence suggests the existence of an additional NR coactivator complex, referred to as the thyroid hormone receptor-associated protein (TRAP) complex, which may function more directly as a bridging complex to the basal transcription machinery. TRAP220, the 220-kDa NR-binding subunit of the complex, has been identified in independent studies using both biochemical and genetic approaches. In light of the functional differences identified between p160 and TRAP coactivator complexes in NR activation, we have attempted to compare interaction and functional characteristics of TIF 2 and TRAP220. Our findings imply that competition between the NR-binding subunits of distinct coactivator complexes may act as a putative regulatory step in establishing either a sequential activation cascade or the formation of independent coactivator complexes.

Mechanistic principles in NR box-dependent interaction between nuclear hormone receptors and the coactivator TIF2.

Nuclear hormone receptors exert transcriptional activation of target genes upon hormone induction via interactions with the basal transcription machinery. This interaction is mediated by cofactors which physically bind to receptors, thereby acting as coactivators or corepressors leading to activation or repression, respectively. Here we report the screening for and cloning of a peroxisome proliferator receptor-interacting protein, the rat homolog of TIF2. By sequence comparison with the related coactivator SRC-1, we identified three short conserved motifs (NR boxes) in both proteins which are the putative binding sites of TIF2 to nuclear hormone receptors. We demonstrate here by generation of amino acid exchanges within the NR boxes that all three boxes located in the receptor interaction domain of TIF2 are necessary and sufficient for interaction. The three boxes individually can bind to hormone receptors but display preferences in binding for certain receptors. In addition, we show that the interaction domain of TIF2 can compete with other AF-2-dependent cofactors for binding to receptors. Finally, we demonstrate cooperative binding of two TIF2 molecules to a heterodimeric nuclear receptor complex even in the presence of only one cognate ligand, indicating an allosteric effect on the heterodimeric partner upon coactivator binding.