Efficacy of laparoscopic fundoplication in patients with chronic cough and gastro-oesophageal reflux.

BACKGROUND: The outcome of anti-reflux surgery in patients with suspected gastro-oesophageal reflux-induced cough is frequently uncertain. The aims of this study were to assess the efficacy of laparoscopic fundoplication for controlling cough in patients with chronic cough without asthma, who have pathologic gastro-oesophageal reflux, and to identify predictors of response. METHODS: From a prospective database of 1598 patients who have undergone laparoscopic fundoplication, 66 (4%) with proven gastro-oesophageal reflux disease (GORD) and chronic cough without asthma were studied. All patients underwent gastroscopy and 24-h pH monitoring before operation. Heartburn and regurgitation were assessed using a modified DeMeester score. Severity of cough before and after surgery was self-assessed by the patient using a visual analog scale at a minimum of 12 months post-operatively (median 43 mo; range: 14-104 mo). Patients were considered to have responded to fundoplication if they had no cough or the cough had improved by 50% or more after operation. RESULTS: Cough and heartburn/regurgitation were relieved in 61% (40/66) and 90% (44/49) of the patients, respectively. The presence of typical GORD symptoms or oesophagitis, and pH study variables did not predict the response of the cough to fundoplication. CONCLUSION: Refinement in the aetiological diagnosis of chronic cough due to GORD is necessary for improved outcome. Patients diagnosed with GORD-related chronic cough need to be counseled regarding their expectations from anti-reflux surgery.

The Impact of Signet Ring Cell Differentiation on Outcome in Patients with Esophageal and Gastroesophageal Junction Adenocarcinoma.

BACKGROUND: Little is known about the association between signet ring cell (SRC) differentiation and response to neoadjuvant chemotherapy (nCT) or neoadjuvant chemoradiotherapy (nCRT) in patients with esophageal and junctional adenocarcinoma (EAC). We aimed to assess if SRC differentiation is associated with survival and response to nCT or nCRT in patients with EAC. METHODS: Patients who underwent nCT and nCRT followed by surgery for EAC from 2000 until 2016 were identified from two institutional prospectively maintained databases. The pretreatment biopsy report or surgical resection specimen was used to differentiate patients into an SRC or non-SRC group. RESULTS: Overall, 129 (19%) of 689 patients included had SRCs (nCT: n = 64; nCRT: n = 65). The SRC group had a more advanced ypT stage (p = 0.003), a higher number of positive lymph nodes in the resection specimen {median (interquartile range [IQR]) 2 [0-5] vs. 1 [0-3]; p = 0.002} and a higher rate of R1/R2 resections (19.4% vs. 12%; p = 0.026). SRC differentiation was not an independent prognostic factor for overall survival (OS) or disease-free survival (DFS). Following nCT, the SRC group had significantly shorter DFS (median [IQR] 12 [5-50] vs. 23 [8-164]; p = 0.013), but not OS, compared with the non-SRC group. In contrast, no differences according to SRC status for OS or DFS were found in patients who underwent nCRT. CONCLUSIONS: SRC differentiation was not independently associated with worse OS in patients with EAC who underwent neoadjuvant therapy and surgery. However, nCRT was associated with greater tumor downstaging and better DFS.

Neoadjuvant chemotherapy or chemoradiotherapy for adenocarcinoma of the esophagus.

BACKGROUND: The optimal treatment strategy for patients with esophageal adenocarcinoma (EAC) remains undetermined. This study compared outcomes in patients undergoing neoadjuvant chemotherapy (nCT) and neoadjuvant chemoradiotherapy (nCRT) for EAC. METHODS: Patients who underwent nCT or nCRT followed by surgery for EAC were identified from a prospective database (2000-2017) and included. After propensity score matching, the impact of the treatments on postoperative complications, in-hospital mortality, pathological outcomes, and survival rates were compared. RESULTS: Of the 396 eligible patients, 262 patients were analysed following matching with 131 patients in both groups. There were no significant differences between the nCT and nCRT groups for overall complications (59% vs 57%, P = 0.802) or in-hospital mortality (2% vs 0%, P = 0.156). Patients who had nCRT had more R0 resections (93% vs 83%, P = 0.013), and higher pathological complete response rates (15% vs 5%, P < 0.001). No differences in 5-year overall survival rates (nCT vs nCRT; 44% vs 33%, P = 0.645) were found. CONCLUSION: In this study no differences between nCT and nCRT were seen in postoperative complications and in-hospital mortality in patients treated for EAC. Inspite of improved complete resection and pathological response there was no difference in the overall survival between the treatment modalities.

Long-term Health-related Quality of Life Following Esophagectomy: A Nonrandomized Comparison of Thoracoscopically Assisted and Open Surgery.

OBJECTIVE: The aim of this study was to assess long-term health-related quality of life (HRQL) in patients after thoracoscopic and open esophagectomy. SUMMARY OF BACKGROUND DATA: Trials comparing minimally invasive with open transthoracic esophagectomy have shown improved short-term outcomes; however, long-term HRQL data are lacking. This prospective nonrandomized study compared HRQL and survival after thoracoscopically assisted McKeown esophagectomy (TAMK) and open transthoracic Ivor Lewis esophagectomy (TTIL) for esophageal or gastroesophageal junction (GEJ) cancer. METHODS: Patients with esophageal or GEJ cancer selected for TAMK or TTIL completed baseline and follow-up HRQL assessments for up to 24 months using the EORTC generic and disease-specific measures, QLQ-C30 and QLQ-OES18. Baseline clinical variables were examined between the treatment groups and changes in mean HRQL scores over time estimated and tested using generalised estimating equations with propensity score (generated by boosted regression) adjustment. RESULTS: Of the 487 patients, 377 underwent TAMK and 110 underwent TTIL. Most clinical variables were similar in the 2 groups; however, there were significantly more patients with AJCC stage 3 disease who underwent TTIL than TAMK (54% vs 32%, P < 0.01) and this was reflected in the survival data.Mean symptom scores for pain were significantly higher in the TTIL group than in TAMK for 2 years postoperatively (P = 0.036). In addition, mean constipation scores were significantly higher for the TTIL group, with a 15-point difference in mean score at 3 months postoperatively (P = 0.037). CONCLUSIONS: This large comprehensive nonrandomized analysis of longitudinal HRQL shows that TTIL is associated with more pain and constipation than TAMK.

CCAT2, a novel noncoding RNA mapping to 8q24, underlies metastatic progression and chromosomal instability in colon cancer.

The functional roles of SNPs within the 8q24 gene desert in the cancer phenotype are not yet well understood. Here, we report that CCAT2, a novel long noncoding RNA transcript (lncRNA) encompassing the rs6983267 SNP, is highly overexpressed in microsatellite-stable colorectal cancer and promotes tumor growth, metastasis, and chromosomal instability. We demonstrate that MYC, miR-17-5p, and miR-20a are up-regulated by CCAT2 through TCF7L2-mediated transcriptional regulation. We further identify the physical interaction between CCAT2 and TCF7L2 resulting in an enhancement of WNT signaling activity. We show that CCAT2 is itself a WNT downstream target, which suggests the existence of a feedback loop. Finally, we demonstrate that the SNP status affects CCAT2 expression and the risk allele G produces more CCAT2 transcript. Our results support a new mechanism of MYC and WNT regulation by the novel lncRNA CCAT2 in colorectal cancer pathogenesis, and provide an alternative explanation of the SNP-conferred cancer risk.

Treatment results of curative gastric resection from a specialist Australian unit: low volume with satisfactory outcomes.

BACKGROUND: The incidence of gastric cancer is decreasing in Australia, yet it remains a common cause of cancer-related mortality. Surgical resection remains the cornerstone of curative treatment. High-volume specialized units have reported superior perioperative and oncological outcomes. The role of D2 lymphadenectomy has been controversial as a result of concerns over increased morbidity. Our aim is to report the perioperative and oncological outcomes of curative gastric resection from a specialist Australian upper GI unit. METHODS: Data from a prospectively maintained database were reviewed for all patients undergoing curative resection for gastric adenocarcinoma from a single unit during a 12-year period. Perioperative and long-term outcomes were compiled. RESULTS: There were 255 curative gastric resections during 12 years. An R0 resection was performed in 96 % with a perioperative mortality rate of 1.6 %. A D2 dissection was performed in 85 % of cases in the past 6 years, with no increase in perioperative morbidity or mortality detected. The 5-year overall survival was 53 %. CONCLUSION: Our results demonstrate that both short- and long-term outcomes of surgical resection in gastric cancer patients, comparable to international high-volume centers, can be achieved in an Australian upper GI unit. A D2 lymph node dissection can be performed safely without any increase in perioperative risk in a specialist unit that has the necessary training but also the perioperative support structures to manage these complex patients.

Defining cure for esophageal cancer: analysis of actual 5-year survivors following esophagectomy.

BACKGROUND: Esophagectomy is the mainstay of curative treatment for localized esophageal cancer. However, what constitutes cure is not well defined. This study was undertaken to characterize actual 5-year survivors following esophagectomy and to determine prognostic factors for disease-specific survival (DSS) from 60 months. MATERIALS AND METHODS: Between 1987 and 2004, 398 consecutive patients underwent esophagectomy and had potential for 5 years follow-up. Clinicopathological factors associated with DSS from 5 years onward were analyzed. RESULTS: Median DSS was 25 months. Neoadjuvant therapy was administered to 159 of 398 (40%). There were 114 of 398 (29%) actual 5-year survivors. On multivariate analysis, 5-year survivors were significantly more likely to have lower T classification, N classification, and R0 resections compared with patients who died less than 5 years after surgery. There were 66 of 398 patients (17%) with positive margins, and 6 of these were 5-year survivors. Of the 114 5-year survivors, 17 (15%) subsequently died of esophageal cancer. Prognostic factors for DSS after surviving 5 years were age and T classification for patients treated with neoadjuvant therapy and surgery alone, respectively. Powerful prognostic factors from time of treatment, including nodal status, were no longer prognostic factors after surviving to 5 years. CONCLUSIONS: No single clinicopathological variable negated survival to 5 years. Prognostication once surviving 5 years is difficult. The majority of 5-year survivors can be considered cured of esophageal cancer.

Factors associated with postoperative pulmonary morbidity after esophagectomy for cancer.

BACKGROUND: Most studies analyzing risk factors for pulmonary morbidity date from the early 1990s. Changes in technology and treatment such as minimally invasive esophagectomy (MIE) and neoadjuvant treatment mandate analysis of more contemporary cohorts. METHODS: Predictive factors for overall and specific pulmonary morbidity in 858 patients undergoing esophagectomy between 1998 and 2008 in five Australian university hospitals were analyzed by logistic regression models. RESULTS: A total of 394 patients underwent open esophagectomy, and 464 patients underwent MIE. A total of 259 patients received neoadjuvant chemoradiotherapy, 139 preoperative chemotherapy alone, and 2 preoperative radiotherapy alone. In-hospital mortality was 3.5%. Smoking and the number of comorbidities were risk factors for overall pulmonary morbidity (odds ratio [OR] 1.47, P = 0.016; OR 1.35, P = 0.001) and pneumonia (OR 2.29, P = 0.002; 1.56, P = 0.005). The risk of respiratory failure was higher in patients with more comorbidities (OR 1.4, P = 0.035). Respiratory comorbidities (OR 3.81, P = 0.017) were strongly predictive of postoperative acute respiratory distress syndrome (ARDS). ARDS (4.51, P = 0.032) or respiratory failure (OR 8.7, P < 0.001), but not anastomotic leak (OR 2.22, P = 0.074), were independent risk factors for death. MIE (OR 0.11, P < 0.001) and thoracic epidural analgesia (OR 0.12, P = 0.003) decreased the risk of respiratory failure. Neoadjuvant treatment was not associated with an increased risk of pulmonary complications. CONCLUSIONS: Preoperative comorbidity and smoking were risk factors for respiratory complications, whereas neoadjuvant treatment was not. MIE and the use of thoracic epidural analgesia decreased the risk of respiratory failure. Respiratory failure and ARDS were the only independent factors associated with an increased risk of in-hospital death, whereas anastomotic leakage was not.

Thoracoscopic-assisted esophagectomy for esophageal cancer: analysis of patterns and prognostic factors for recurrence.

OBJECTIVE: The authors report the recurrence pattern of esophageal cancer after thoracoscopic-assisted esophagectomy (TAE), comparing it to the recurrence pattern after open surgery and identify prognostic factors for recurrence. SUMMARY OF BACKGROUND DATA: To improve long-term survival for esophageal cancer radical surgery has been proposed increasingly, however, recurrent disease remains a problem. Opinion is divided as to the adequacy of resection possible using minimally invasive techniques with concerns that there may be an increased incidence in locoregional recurrence. METHODS: A total of 221 patients who underwent esophagectomy at the Princess Alexandra Hospital without any neoadjuvant or adjuvant therapy were identified from a prospective database. Patients were followed up for the detection of symptomatic recurrence for a median of 59 months. RESULTS: Within this group 165 patients underwent TAE and 56 an open transthoracic esophagectomy (TTE). The 5-year overall recurrence rate was 133/221 (60%). The 5-year rates of symptomatic first recurrence following TAE was 4%, 9%, and 47% for local, regional, and distant recurrence, respectively. The 5-year rates of symptomatic first recurrence following TTE was 5%, 18%, and 55% for local, regional, and distant recurrence, respectively. Operative approach was not a prognostic factor for any type of recurrence. Independent prognostic factors associated with locoregional recurrence were positive margins and number of positive nodes. Distant recurrence was associated with T stage, differentiation, tumor length >6 cm, and number of positive nodes. CONCLUSION: Distant recurrence remains a significant problem in esophageal cancer. TAE achieved adequate locoregional control and compared favorably with open TTE.

Risk stratification for early esophageal adenocarcinoma: analysis of lymphatic spread and prognostic factors.

BACKGROUND: Knowledge of factors related to outcome is vital for the selection of therapeutic alternatives for patients with early (T1) esophageal adenocarcinoma. This study was undertaken to determine predictors of lymphatic spread and prognostic factors for T1 esophageal adenocarcinoma following esophagectomy. MATERIALS AND METHODS: A prospectively maintained database identified 85 patients with T1 esophageal adenocarcinoma who underwent esophagectomy without neoadjuvant therapy. Depth of tumor invasion (T stage) was subdivided into mucosal (T1a) or submucosal invasion (T1b). Median follow-up was 59 months. RESULTS: Thoracoscopically assisted 3-phase esophagectomy was performed in 73 of 85 patients (86%). Lymph node metastases (N stage) were identified in 9 of 85 patients (11%). Depth of tumor invasion (T stage), lymphovascular invasion (LVI), and poor differentiation were associated with N stage. The patients could be stratified into 4 risk groups for lymph node metastases: group I--T1a (0 of 35 patients [0%] with positive nodes); group II--T1b, well/moderate differentiation and no LVI (1 of 28 patients [4%] with positive nodes); group III--T1b, poor differentiation and no LVI (2 of 9 patients [22%] with positive nodes); and group IV--T1b any grade with LVI (6 of 13 patients [46%] with positive nodes). Survival analyses found T stage, N stage, LVI, and poor differentiation to be significant prognostic factors. CONCLUSIONS: Risk stratification is possible for patents with T1 esophageal adenocarcinoma. Local resection techniques without lymphadenectomy may be alternatives for T1a tumors. Esophagectomy should remain the standard of care for patients with T1b tumors and those with LVI or poor differentiation considered for neoadjuvant therapy.

Laparoscopic upper gut surgery.

Australian surgeons have been prominent in the introduction, development, and consolidation of laparoscopic surgery of the upper gut. In doing this, some of the very best principles of surgical innovation have been in evidence: preliminary animal work in which to test hypotheses and techniques, followed by careful application and documentation in the clinical setting, randomized clinical trials and finally academic reporting and ongoing development. This review documents the introduction of laparoscopic surgery for gastroesophageal reflux, hiatus hernia, achalasia, gastroesophageal malignancy, obesity, and a range of emergency conditions in Australia. Those involved are regarded as world leaders in their field. A vital component of this success has been the close cooperation between surgeons and gastroenterologists within the Gastroenterological Society of Australia.

Similarity of aberrant DNA methylation in Barrett's esophagus and esophageal adenocarcinoma.

BACKGROUND: Barrett's esophagus (BE) is the metaplastic replacement of squamous with columnar epithelium in the esophagus, as a result of reflux. It is the major risk factor for the development of esophageal adenocarcinoma (EAC). Methylation of CpG dinucleotides of normally unmethylated genes is associated with silencing of their expression, and is common in EAC. This study was designed to determine at what stage, in the progression from BE to EAC, methylation of key genes occurs. RESULTS: We examined nine genes (APC, CDKN2A, ID4, MGMT, RBP1, RUNX3, SFRP1, TIMP3, and TMEFF2), frequently methylated in multiple cancer types, in a panel of squamous (19 biopsies from patients without BE or EAC, 16 from patients with BE, 21 from patients with EAC), BE (40 metaplastic, seven high grade dysplastic) and 37 EAC tissues. The methylation frequency, the percentage of samples that had any extent of methylation, for each of the nine genes in the EAC (95%, 59%, 76%, 57%, 70%, 73%, 95%, 74% and 83% respectively) was significantly higher than in any of the squamous groups. The methylation frequency for each of the nine genes in the metaplastic BE (95%, 28%, 78%, 48%, 58%, 48%, 93%, 88% and 75% respectively) was significantly higher than in the squamous samples except for CDKN2A and RBP1. The methylation frequency did not differ between BE and EAC samples, except for CDKN2A and RUNX3 which were significantly higher in EAC. The methylation extent was an estimate of both the number of methylated alleles and the density of methylation on these alleles. This was significantly greater in EAC than in metaplastic BE for all genes except APC, MGMT and TIMP3. There was no significant difference in methylation extent for any gene between high grade dysplastic BE and EAC. CONCLUSION: We found significant methylation in metaplastic BE, which for seven of the nine genes studied did not differ in frequency from that found in EAC. This is also the first report of gene silencing by methylation of ID4 in BE or EAC. This study suggests that metaplastic BE is a highly abnormal tissue, more similar to cancer tissue than to normal epithelium.

Refining esophageal cancer staging after neoadjuvant therapy: importance of treatment response.

OBJECTIVE: Accurate staging is vital for esophageal cancer management. The utility of the American Joint Committee on Cancer (AJCC) staging system 6th edition for esophageal cancer has been questioned for resected patients who receive neoadjuvant chemoradiotherapy (CRT). This study was undertaken to assess the AJCC staging system for patients with esophageal cancer that have received neoadjuvant CRT and to identify clinicopathological variables that predict survival. METHODS: Review of a prospective esophageal cancer database was undertaken for patients that received neoadjuvant CRT and resection. Primary tumor response was defined as major (10% residual tumor cells). Cox regression and concordance analyses were used to determine prognostic factors. Median follow-up was 61 months. RESULTS: Of 131 patients with invasive cancer, there were 40/131 (31%) with squamous cell carcinoma (SCC) and 88/131 (65%) with adenocarcinoma. The procedure-related mortality rate was 3.8%. Median survival was 33 months. A major response was demonstrated by 79/131 (60%) patients. Survival analyses found that the AJCC 6th edition was unable to discriminate between stages 0, I, and IIa or stages IIb and III. Multivariate survival analyses found age, pretreatment tumor length >6 cm, positive lymph nodes, and a major tumor response were independent prognostic factors. These data were used to derive a new staging system that had improved discrimination of stage groups over the current AJCC system. CONCLUSION: The current AJCC staging system for esophageal cancer is inadequate for patients that receive neoadjuvant CRT. Refinement of the AJCC staging system should include primary tumor response for patients receiving neoadjuvant CRT.

Neoadjuvant therapy reduces cardiopulmunary function in patients undegoing oesophagectomy.

Neoadjuvant therapy (NAT) for oesophageal cancer may reduce cardiopulmonary function, assessed by cardiopulmonary exercise testing (CPEX). Impaired cardiopulmonary function is associated with mortality following esophagectomy. We sought to assess the impact of NAT on cardiopulmonary function using CPEX and assessing the clinical relevance of any change in particular if changes were associated with post-operative morbidity. This was a prospective, cohort study of 40 patients in whom CPEX was performed before and after NAT. Thirty-eight patients underwent surgery and follow-up with perioperative outcomes measured. The primary variables derived from CPEX were the anaerobic threshold (AT) and peak oxygen uptake (V˙O2peak). There were significant reductions in the AT (pre-NAT: 12.4 ±â€¯3.0 vs. post-NAT 10.6 ±â€¯2.0 mL kg-1.min-1; p = 0.001). This reduction was also evident for V˙O2peak (pre-NAT: 16.6 ±â€¯3.6 vs. post-NAT 14.9 ±â€¯3.7 mL kg-1.min-1; p = 0.004). The relative reduction in V˙O2peak was greater in chemotherapy patients who developed any peri-operative morbidity (p = 0.04). For patients who underwent chemoradiotherapy, there was a significantly greater relative reduction in AT (p = 0.03) for those who encountered a respiratory complication. Cardiopulmonary function significantly declined as a result of NAT prior to oesophagectomy. The reduction in AT and V˙O2peak was similar in both the chemotherapy and chemoradiotherapy groups.

Radiofrequency ablation of liver tumors: a systematic review.

OBJECTIVES: To systematically review radiofrequency ablation (RFA) for treating liver tumors. DATA SOURCES: Databases were searched in July 2003. STUDY SELECTION: Studies comparing RFA with other therapies for hepatocellular carcinoma (HCC) and colorectal liver metastases (CLM) plus selected case series for CLM. DATA EXTRACTION: One researcher used standardized data extraction tables developed before the study, and these were checked by a second researcher. DATA SYNTHESIS: For HCC, 13 comparative studies were included, 4 of which were randomized, controlled trials. For CLM, 13 studies were included, 2 of which were nonrandomized comparative studies and 11 that were case series. There did not seem to be any distinct differences in the complication rates between RFA and any of the other procedures for treatment of HCC. The local recurrence rate at 2 years showed a statistically significant benefit for RFA over percutaneous ethanol injection for treatment of HCC (6% vs 26%, 1 randomized, controlled trial). Local recurrence was reported to be more common after RFA than after laser-induced thermotherapy, and a higher recurrence rate and a shorter time to recurrence were associated with RFA compared with surgical resection (1 nonrandomized study each). For CLM, the postoperative complication rate ranged from 0% to 33% (3 case series). Survival after diagnosis was shorter in the CLM group treated with RFA than in the surgical resection group (1 nonrandomized study). The CLM local recurrence rate after RFA ranged from 4% to 55% (6 case series). CONCLUSIONS: Radiofrequency ablation may be more effective than other treatments in terms of less recurrence of HCC and may be as safe, although the evidence is scant. There was not enough evidence to determine the safety or efficacy of RFA for treatment of CLM.

Expression of HOXB2, a retinoic acid signaling target in pancreatic cancer and pancreatic intraepithelial neoplasia.

PURPOSE: Despite significant progress in understanding the molecular pathology of pancreatic cancer and its precursor lesion: pancreatic intraepithelial neoplasia (PanIN), there remain no molecules with proven clinical utility as prognostic or therapeutic markers. Here, we used oligonucleotide microarrays to interrogate mRNA expression of pancreatic cancer tissue and normal pancreas to identify novel molecular pathways dysregulated in the development and progression of pancreatic cancer. EXPERIMENTAL DESIGN: RNA was hybridized to Affymetrix Genechip HG-U133 oligonucleotide microarrays. A relational database integrating data from publicly available resources was created to identify candidate genes potentially relevant to pancreatic cancer. The protein expression of one candidate, homeobox B2 (HOXB2), in PanIN and pancreatic cancer was assessed using immunohistochemistry. RESULTS: We identified aberrant expression of several components of the retinoic acid (RA) signaling pathway (RARalpha, MUC4, Id-1, MMP9, uPAR, HB-EGF, HOXB6, and HOXB2), many of which are known to be aberrantly expressed in pancreatic cancer and PanIN. HOXB2, a downstream target of RA, was up-regulated 6.7-fold in pancreatic cancer compared with normal pancreas. Immunohistochemistry revealed ectopic expression of HOXB2 in 15% of early PanIN lesions and 48 of 128 (38%) pancreatic cancer specimens. Expression of HOXB2 was associated with nonresectable tumors and was an independent predictor of poor survival in resected tumors. CONCLUSIONS: We identified aberrant expression of RA signaling components in pancreatic cancer, including HOXB2, which was expressed in a proportion of PanIN lesions. Ectopic expression of HOXB2 was associated with a poor prognosis for all patients with pancreatic cancer and was an independent predictor of survival in patients who underwent resection.

Expression of the CD44v2-10 isoform confers a metastatic phenotype: importance of the heparan sulfate attachment site CD44v3.

We expressed the full-length CD44v2-10 isoform in SKHep1 cells, a nonmetastatic human hepatocellular carcinoma cell line that does not express any endogenous CD44v isoforms. In SCID mice, expression of CD44v2-10 by SKHep1 cells had no effect on s.c. primary tumor development but caused pulmonary metastases in 41% (7 of 17) of animals compared with control SKHep1 cells (0 of 16; P < 0.01). CD44v2-10 expression by SKHep1 cells resulted in enhanced heparan sulfate (HS) attachment and an enhanced capacity to bind heparin-binding growth factors. Mutation of the v3 domain to prevent HS attachment and growth factor binding abolished the metastatic phenotype, demonstrating that HS modification of CD44v2-10 plays a critical role in the development of metastases in this model. However, in vitro proliferation, motility, and invasion were not altered by CD44v2-10 expression.

Interactions among smoking, obesity, and symptoms of acid reflux in Barrett's esophagus.

BACKGROUND: Barrett's esophagus, a metaplastic precursor to esophageal adenocarcinoma, is becoming increasingly prevalent in many populations. Clinical studies suggest acid reflux causes Barrett's esophagus; however, no population-based estimates of risk have been reported, and the role of other health factors in modifying risk is unclear. METHODS: We conducted a population-based case-control study in Brisbane, Australia. Cases were 167 patients with histologically confirmed Barrett's esophagus diagnosed between February and December 2003. Age-matched and sex-matched controls (n = 261) were randomly selected from a population register. Data on exposure to self-reported symptoms of acid reflux, smoking, obesity, and other factors were collected through self-completed questionnaires followed by telephone interview. Risks of Barrett's esophagus and Barrett's esophagus with dysplasia associated with these exposures were estimated by the odds ratio (OR) and 95% confidence interval (95% CI), both crude and adjusted for other factors. RESULTS: Self-reported weekly episodes of acid reflux were associated with greatly increased risks of Barrett's esophagus (adjusted OR, 29.7; 95% CI, 12.2-72.6) and Barrett's esophagus with dysplasia (OR, 59.7; 95% CI, 18.5-193). Smoking was also associated with risk of Barrett's esophagus. We found evidence of interactions between symptoms of acid reflux and smoking and obesity. Obese people with self-reported symptoms of acid reflux had markedly higher risks of Barrett's esophagus (OR, 34.4; 95% CI, 6.3-188) than people with reflux alone (OR, 9.3; 95% CI, 1.4-62.2) or obesity alone (OR, 0.7; 95% CI, 0.2-2.4). Similarly, those reporting both acid reflux symptoms and smoking were at substantially higher risks of Barrett's esophagus (OR, 51.4; 95% CI, 14.1-188) than those reporting acid reflux or smoking alone. CONCLUSIONS: Although history of symptoms of acid reflux is the principle factor associated with Barrett's esophagus, risks are substantially increased by obesity and smoking.

Endothelial cell serine proteases expressed during vascular morphogenesis and angiogenesis.

Many serine proteases play important regulatory roles in complex biological systems, but only a few have been linked directly with capillary morphogenesis and angiogenesis. Here we provide evidence that serine protease activities, independent of the plasminogen activation cascade, are required for microvascular endothelial cell reorganization and capillary morphogenesis in vitro. A homology cloning approach targeting conserved motifs present in all serine proteases, was used to identify candidate serine proteases involved in these processes, and revealed 5 genes (acrosin, testisin, neurosin, PSP and neurotrypsin), none of which had been associated previously with expression in endothelial cells. A subsequent gene-specific RT-PCR screen for 22 serine proteases confirmed expression of these 5 genes and identified 7 additional serine protease genes expressed by human endothelial cells, urokinase-type plasminogen activator, protein C, TMPRSS2, hepsin, matriptase/MT-SP1, dipeptidylpeptidase IV, and seprase. Differences in serine protease gene expression between microvascular and human umbilical vein endothelial cells (HUVECs) were identified and several serine protease genes were found to be regulated by the nature of the substratum, ie. artificial basement membrane or fibrillar type I collagen. mRNA transcripts of several serine protease genes were associated with blood vessels in vivo by in situ hybridization of human tissue specimens. These data suggest a potential role for serine proteases, not previously associated with endothelium, in vascular function and angiogenesis.

Expression of the cell surface mucin gene family in adenocarcinomas.

Cell surface mucins are complex glycoproteins expressed on the apical membrane surface of mucosal epithelial cells. In malignant epithelial cells they are thought to influence cell adhesion, and are clinical targets for tumor immunotherapy and serum tumor marker assays. We have compared expression of MUC1, MUC3, MUC4, MUC11, MUC12 and MUC13 mRNA in epithelial cancers and/or cell lines with non-malignant tissues. In non-malignant tissues, MUC3, 4, 11, 12 and 13 were expressed at highest levels in gastrointestinal tissues, whereas MUC1 was more widely distributed. Significant down-regulation of the MUC4, MUC12 and MUC13 genes was observed in colonic cancers compared with normal tissue, whereas MUC1 was upregulated. In rectal cancers, levels of all six mucin genes were not significantly different to those in normal rectal tissues. Both MUC1 and MUC4 were down-regulated in gastric cancers, whereas cancer and normal tissue levels were similar for MUC3, 11, 12 and 13. In esophageal cancers there was a general trend toward higher levels than in normal tissue for MUC1, 3, 12 and 13. In ovarian cancers MUC1 levels were very high, whereas only low levels of all other mucins were observed. We also report expression in renal cell carcinomas, bladder carcinomas and breast cancer cell lines. The reported expression profiles of the cell surface mucin gene family will help direct biological and clinical studies of these molecules in mucosal biology, and in malignant and inflammatory diseases of epithelial tissues.