Cigarette smoke mediates epigenetic repression of miR-217 during esophageal adenocarcinogenesis.

Although microRNAs (miRs) have been implicated in the pathogenesis of various human malignancies, limited information is available regarding mechanisms by which these noncoding RNAs contribute to initiation and progression of tobacco-induced esophageal cancers. In this study, array and quantitative reverse transcriptase-PCR techniques were used to examine miR expression in immortalized esophageal epithelia (IEE) and esophageal adenocarcinoma (EAC) cells cultured in normal media with or without cigarette smoke condensate (CSC). Under relevant exposure conditions, CSC significantly decreased miR-217 expression in these cells. Endogenous levels of miR-217 expression in cultured EAC cells (EACC)/primary EACs were significantly lower than those observed in IEE/ paired normal esophageal tissues. RNA crosslink immunoprecipitation, quantitative reverse transcriptase-PCR (qRT-PCR) and immunoblot experiments demonstrated direct interaction of miR-217 with kallikrein 7 (KLK7), encoding a putative oncogene not previously implicated in EAC. Repression of miR-217 correlated with increased levels of KLK7 in primary EACs, particularly those from smokers. Chromatin and methylated DNA immunoprecipitation experiments demonstrated that CSC-mediated repression of miR-217 coincided with DNMT3b-dependent hypermethylation and decreased occupancy of nuclear factor 1 within the miR-217 genomic locus. Deoxyazacytidine induced miR-217 expression and downregulated KLK7 in EACC; deoxyazacytidine also attenuated CSC-mediated miR-217 repression and upregulation of KLK7 in IEE and EACC. Overexpression of miR-217 significantly decreased, whereas overexpression of KLK7 increased proliferation, invasion and tumorigenicity of EACC. Collectively, these data demonstrate that epigenetic repression of miR-217 contributes to the pathogenesis of EAC via upregulation of KLK7 and suggest that restoration of miR-217 expression may be a novel treatment strategy for these malignancies.

Fourier transform infrared (FTIR) spectromicroscopic characterization of stem-like cell populations in human esophageal normal and adenocarcinoma cell lines.

We have tested an approach to identify putative cancer stem cells that involves measurement of the infrared absorption spectrum of individual cells in an aqueous environment, and their subsequent classification using multivariate data analysis techniques. Two primary esophageal cell lines were characterized: the immortalized normal esophageal epithelial cell line, Het-1A, and the esophageal adenocarcinoma cell line, OE33. In addition, we also evaluated spheroids, reflecting stem-like cell populations, which were derived from each parent cell line when grown in serum-free media. As differences in cell size appeared to be a strong discriminating factor, a correction needs to be performed to allow a reliable classification based on infrared absorption spectra. We demonstrated that stem-like cells derived from Het-1A could easily be discriminated on the basis of absorbance differences in the 1000-1200 cm(-1) spectral interval, whereas this was not possible for OE33. Furthermore, we found that changes due to aging of OE33 cells in culture dominated the infrared absorption spectra and somewhat limited the potential of this approach to identify stem-like cell populations using this in vitro model system.

Obesity and lifestyle risk factors for gastroesophageal reflux disease, Barrett esophagus and esophageal adenocarcinoma.

The aim of this study was to examine the association of obesity with esophageal adenocarcinoma, and with the precursor lesions Barrett esophagus and gastroesophageal reflux disease (GERD). This case-control study included cases with GERD (n = 142), Barrett esophagus (n = 130), and esophageal adenocarcinoma (n = 57). Controls comprised 102 asymptomatic individuals. Using logistic regression methods, we compared obesity rates between cases and controls adjusting for differences in age, gender, and lifestyle risk factors. Relative to normal weight, obese individuals were at increased risk for esophageal adenocarcinoma (Odds Ratio [OR] 4.67, 95% Confidence Interval [CI] 1.27-17.9). Diets high in vitamin C were associated with a lower risk for GERD (OR 0.40, 95% CI 0.19-0.87), Barrett esophagus (OR 0.44, 95% CI 0.20-0.98), and esophageal adenocarcinoma (OR 0.21, 95% CI 0.06-0.77). For the more established risk factors, we confirmed that smoking was a significant risk factor for esophageal adenocarcinoma, and that increased liquor consumption was associated with GERD and Barrett esophagus. In light of the current obesity epidemic, esophageal adenocarcinoma incidence rates are expected to continue to increase. Successful promotion of healthy body weight and diets high in vitamin C may substantially reduce the incidence of this disease.

Biomarkers in the molecular pathogenesis of esophageal (Barrett) adenocarcinoma.

Since the early 1970s, a dramatic change has occurred in the epidemiology of esophageal malignancy in both North America and Europe: the incidence of adenocarcinomas of the lower esophagus and esophagogastric junction is increasing. Several lifestyle factors are implicated in this change, including gastroesophageal reflux disease (GERD). Primary esophageal adenocarcinomas are thought to arise from Barrett esophagus, an acquired condition in which the normal esophageal squamous epithelium is replaced by a specialized metaplastic columnar-cell-lined epithelium.Today, gerd is recognized as an important risk factor in Barrett esophagus. Progression of Barrett esophagus to invasive adenocarcinoma is reflected histologically by the metaplasia-dysplasia-carcinoma sequence. Although several molecular alterations associated with progression of Barrett esophagus to invasive adenocarcinoma have been identified, relatively few will ultimately have clinical application. Currently, the histologic finding of high-grade dysplasia remains the most reliable predictor of progression to invasive esophageal adenocarcinoma. However other promising molecular biomarkers include aneuploidy; 17p loss of heterozygosity, which implicates the TP53 tumour suppressor gene; cyclin D1 protein overexpression; and p16 alterations. It is anticipated that models incorporating combinations of objective scores of sociodemographic and lifestyle risk factors (that is, age, sex, body mass index), severity of gerd, endoscopic and histologic findings, and a panel of biomarkers will be developed to better identify patients with Barrett esophagus at increased risk for malignant progression, leading to more rational endoscopic surveillance and screening programs.

Preoperative mitomycin, ifosfamide, and cisplatin followed by esophagectomy in squamous cell carcinoma of the esophagus: pathologic complete response induced by chemotherapy leads to long-term survival.

PURPOSE: Squamous cell carcinoma of the esophagus remains an aggressive disease with a poor prognosis, even after curative-intent surgery. This article analyzes the impact of preoperative chemotherapy with mitomycin, ifosfamide, and cisplatin (MIC) on a cohort of 68 patients. PATIENTS AND METHODS: From 1988 to 1994, 68 patients with potentially operable squamous cell carcinoma of the esophagus were entered onto two phase II trials of neoadjuvant chemotherapy with mitomycin 6 mg/m2, ifosfamide 3 g/m2, and cisplatin 50 mg/m2 and received between two and four cycles of treatment at 3-weekly intervals. Two patients were removed from the analysis when they were found to have malignancy other than squamous cell carcinoma of the esophagus. RESULTS: Forty (61%) of 66 patients had a radiologic response to chemotherapy (18 complete responses and 22 partial responses), and 52 (79%) of 66 patients went on to have the primary tumor resected. There were nine pathologic complete responders, seven of whom remain fit and well after at least 60 months of follow-up. The overall median survival was 12.4 months (95% confidence interval, 9.6 to 18.8 months). The complete response and node-negative patients survived significantly longer than those in other categories (log-rank chi2 = 18.8; P <.001): on average 13 months longer than the node-positive or nonresected category (22.0 v 9.4 months). The toxicity of the regimen was low. CONCLUSION: MIC is an easily administered, well-tolerated, and efficacious regimen as neoadjuvant therapy for patients with squamous cell carcinoma of the esophagus. These results warrant further investigation.

Associations between genetic polymorphisms of Phase I and II metabolizing enzymes, p53 and susceptibility to esophageal adenocarcinoma.

The objectives of this exploratory case-control study were to evaluate whether genetic polymorphisms of selected Phase I and II metabolizing enzymes are associated with the risk of developing primary esophageal adenocarcinoma, and to investigate potential associations between genotypes and p53 tumor suppressor gene alterations. Cases comprised 45 patients with surgically resected esophageal adenocarcinomas, defined according to strict clinico-pathologic criteria. PCR-based assays (RFLP/SSCP) were used to genotype cytochrome P450 (CYP) 1A1 [MspI; Ile:Val], microsomal epoxide hydroxylase (mEH) (fast and slow alleles), and glutathione S-transferase (GST) T1, M1 and P1. Healthy controls (n=45) from the same geographic region were matched for age, gender and smoking history. For GSTP1, the Ile/Val (a/b) and Val/Val (b/b) variants were seen at increased frequency in cases compared to controls (49% versus 27% and 15% versus 9%, respectively), although these differences achieved only borderline statistical significance (P=0.09). For mEH (exon 3), the presence of the Tyr polymorphism (slow allele) was reduced in cases (42%) compared to controls (53%; P=0.05). Predicted high mEH activity was seen more frequently in cases than controls (OR, 2.2; 95% CI, 0.7-7.3). Polymorphism frequencies for GSTT1, GSTM1, and CYP1A1 were not statistically different between cases and controls. Cases with the GSTT1 null genotype had tumors with altered p53 more frequently than did cases with the common form of GSTT1 (25 versus 6%, respectively; P=0.08). We conclude that polymorphisms of GSTP1 and mEH may be implicated in individual susceptibility to esophageal adenocarcinoma, possibly as a result of increased Phase I activation (mEH) and impaired Phase II detoxification (GSTP1). GSTT1 may also play a role in esophageal tumorigenesis through a pathway that involves abnormalities in the p53 tumor suppressor gene.

Evolution and critical appraisal of anastomotic technique following resection of esophageal adenocarcinoma.

The aim of this study was to critically evaluate acute and long-term complications of hand-sewn and semimechanical cervical esophagogastric anastomosis following resection of primary esophageal adenocarcinoma. Between February 1991 and 2001, 91 consecutive patients underwent subtotal esophagectomy (transthoracic, n=49; transhiatal, n=42), transposing a gastric tube based on the right gastroepiploic artery. All esophagogastric anastomoses were performed in the left neck using a hand-sewn technique (n=53) and, from September 1997, a side-to-side semimechanical technique (n=38). Outcomes evaluated were anastomotic leak rates, length of stay, and development of strictures. Postoperative mortality was 4.4% (all cardiopulmonary causes). Fifty-eight patients (63.7%) had an uncomplicated postoperative course, with a median postoperative length of stay of 10 days (vs. 20 days with associated morbidity; P

Results of Collis gastroplasty and selective fundoplication, using a left thoracoabdominal approach, for failed antireflux surgery.

OBJECTIVE: To study patterns of failure following primary antireflux surgery and to evaluate efficacy of reoperation using a left thoracoabdominal Collis gastroplasty and selective fundoplication. METHODS: Thirty-one patients who underwent reoperative antireflux surgery between 1991 and 2000 were studied. Transabdominal fundoplication had been performed in 21 patients, and ten patients had a partial fundoplication by left thoracotomy, 1-33 years (mean, 15 years) previously. All patients presented with clinically disabling symptoms. Objective studies documented for all patients, a disrupted fundoplication, a short esophagus, and an associated hiatus hernia (Type I: 21 patients, 68%; Type III: ten patients, 32%), esophagitis (nine patients, 29%), and Barrett's mucosa (five patients, 16%). Abnormal esophageal motility was found in nine of 26 (36%) patients studied. All patients were reoperated using a left thoracoabdominal approach, with epidural analgesia. A Collis gastroplasty was used to lengthen the esophagus, incorporating a complete (24 patients, 77%) or partial (seven patients, 23%) fundoplication based of preoperative esophageal function studies. RESULTS: There was no perioperative mortality. Median length of hospitalization was 8 days, and was uncomplicated for 18 (58%) patients. Postoperative morbidity was considered minimal, and comprised left lower lobe infiltrates (six patients, 19%), atrial fibrillation (three patients, 10%), urinary tract infection (one patient, 3%), superficial wound infection (one patient, 3%), aspiration (one patient, 3%), and nausea (one patient, 3%). Median follow-up was 42 months (6-105 months), and was complete for 29 patients. Six patients (21%) had moderate-severe post-thoracotomy pain, for up to 18 months postoperatively, and five patients (17%) required esophageal dilation, ranging from two to six dilations within the first 6 months after surgery. Overall, 93% (27/29) of patients were satisfied with the results of surgery, in terms of quality of swallowing and control of preoperative symptoms. CONCLUSIONS: In this series, failure of primary antireflux surgery was related to short esophagus. Intermediate-term subjective results of reoperative antireflux surgery were good for selected patients who undergo esophageal lengthening and fundoplication. The left thoracoabdominal approach was safe, generally well tolerated, and provided excellent exposure of the esophagogastric junction for complex reoperative antireflux surgery.

A study of smoking, p53 tumor suppressor gene alterations and non-small cell lung cancer.

PURPOSE: The purpose of this study was to investigate the relationship between smoking and p53 tumor suppressor gene alterations, and their association with clinicopathologic features and prognosis in non-small cell lung cancer (NSCLC). METHODS: For 111 of 119 stage I-III NSCLC patients that had been followed prospectively, tumor p53 protein accumulation was measured immunohistochemically (IHC). Staining was evaluated as a score (p53IHCS) combining intensity and percent distribution. RESULTS: Forty-eight of 111 (43%) tumors had p53IHCS > 1. p53 IHC was associated with increasing tumor size (T) (p = 0.035), nodal status (N) (p = 0.091), stage (p = 0.054), and histology: squamous cell carcinoma (70%) and adenocarcinoma (27%) (p = 0.0002). In logistic regression analysis, p53 IHC was associated with squamous cell histology versus other histotypes [adjusted odds ratio (OR)5.90, 95% confidence interval (CI) 2.34-14.90]. p53 IHC was not associated with smoking variables. In multivariate proportional hazards analysis, p53IHCS and pack-years smoked (PY), both as continuous variables, were negative prognostic factors. The adjusted hazard ratios (HR) for the survival outcome recurrence for p53IHCS and PY were 1.20 (95% CI 1.02-1.40) and 1.03 (95% CI 1.01-1.04), and for death due to recurrent disease (DRD) were 1.35 (95% CI 1.11-1.64) and 1.03 (95% CI 1.01-1.04), respectively. Comparing the 75th percentile to the baseline 0, the adjusted HR for p53IHCS (5 vs. 0) was 4.5 and for PY (55 vs. 0) was 5.1 for the outcome DRD. Both variables demonstrated a dose-response relationship with survival. CONCLUSIONS: PY and p53IHCS are significant, independent and important predictors of recurrence and DRD in stage I-III NSCLC.

What is the optimal distal resection margin for esophageal carcinoma?

BACKGROUND: Whereas a proximal resection margin of 12 cm is recommended for complete resection of esophageal cancer, the extent of distal resection is unclear. METHODS: We examined distal resection margins in a consecutive series of patients who underwent esophagectomy for squamous cell carcinomas (n = 50), primary esophageal adenocarcinomas (n = 100), and adenocarcinomas of the cardia (n = 39), in whom all macroscopic tumor was judged to be completely resected. RESULTS: Microscopic tumor was found at a 3-cm distal resection margin for one multifocal squamous cell carcinoma. Positive distal resection margins were seen in 12% (12 of 100 patients) of primary esophageal adenocarcinomas (median, 2 cm versus 4 cm if negative; p = 0.002, Wilcoxon) and 28% (11 of 39 patients) of cardia adenocarcinomas (median, 1 cm versus 3 cm if negative; p = 0.02, Wilcoxon). Although pathologic stage was shown to be the only significant predictor of overall survival (Hazard ratio [HR] 1.8; 95% confidence interval 1.2 to 2.6; p = 0.007), there was a trend toward reduced postoperative survival for patients with histologically positive distal resection margins, in particular for patients with cardia adenocarcinomas (median, 15.4 months versus 5.7 months if negative; p = 0.0001). CONCLUSIONS: To achieve consistently negative distal resection margins, we recommend resection of at least 5 cm of macroscopically normal foregut below the distal margin of the primary tumor.

Surgeons' assessment of symptoms suggesting extrathoracic metastases in patients with lung cancer. Canadian Lung Oncology Group.

BACKGROUND: In patients with apparently operable non-small cell lung cancer (NSCLC), clinicians often omit investigation for M disease in asymptomatic patients. Previous investigations have not specified in detail what is meant by "symptomatic," and this could differ between surgeons. We have investigated the extent to which surgeons' criteria differ for presence of symptoms. METHODS: Participating surgeons from seven centers, enrolled patients they judged "asymptomatic" in a randomized trial of investigational strategies for NSCLC. Patients completed a structured questionnaire describing symptoms of the central nervous system (CNS). In 685 patients, we documented CNS symptom recurrence after resectional surgery over 1 year of follow-up. RESULTS: Two centers enrolled only patients without even the mildest symptoms. Three centers took an intermediate approach, occasionally classifying patients with mild symptoms as "asymptomatic" and thus enrolling them in the trial. Two centers classified an appreciable number of patients with minimal symptoms, and occasionally with more than minimal symptoms, as "asymptomatic." Patients with even mild CNS symptoms were more likely to subsequently present with CNS metastases. CONCLUSIONS: Thoracic surgeons differ in their ideas of what may constitute the symptoms of M disease. Patients with structured questionnaire results that suggest symptoms of CNS disease are more likely to have CNS symptom recurrence after resectional surgery.

Molecular evolution of the metaplasia-dysplasia-adenocarcinoma sequence in the esophagus.

The incidence of adenocarcinoma of the esophagus has been increasing in developing countries over the last three decades and probably reflects a genuine increase in the incidence of its recognized precursor lesion, Barrett's metaplasia. Despite advances in multimodality therapy, the prognosis for invasive esophageal adenocarcinoma is poor. An improved understanding of the molecular biology of this disease may allow improved diagnosis, therapy, and prognosis. We focus on recent developments in the molecular and cell biology of Barrett's metaplasia, a heterogeneous lesion affecting the transitional zone of the gastro-esophageal junction whose associated molecular alterations may vary both in nature and temporally. Early premalignant clones produce biological and genetic heterogeneity as seen by multiple p53 mutations, p16 mutations, aneuploidy, and abnormal methylation resulting in stepwise changes in differentiation, proliferation, and apoptosis, allowing disease progression under selective pressure. Abnormalities in expression of growth factors of the epidermal growth factor family and cell adhesion molecules, especially cadherin/catenin complexes, may occur early in invasion. Exploitation of these molecular events may lead to a more appropriate diagnosis and understanding of these lesions in the future.

Characterization of cytochrome P450 expression in human oesophageal mucosa.

The expression of cytochrome (CYP) P450 enzymes in human oesophageal mucosa was investigated in a total of 25 histologically non-neoplastic surgical tissue specimens by using specific antibodies in immunoblots and by RT-PCR mRNA analysis. The presence of CYP1A, 2E1, 3A and 4A enzymes was demonstrated by both techniques; CYP2A reactive protein was also detected by immunoblot. The presence of CYP4B1 mRNA was established but no specific antibody was available for detection of the corresponding protein by immunoblot. CYP2B6/7 mRNA was not detected in any sample. The mRNA transcripts for CYP1A1, 2E1, 4A11 and 4B1 were consistently detected in the majority of samples (>84%), whereas CYP1A2 mRNA was only detected in 11 of 19 specimens examined. An RT-PCR method to differentiate CYP3A4 and 3A5 mRNA was developed. This demonstrated CYP3A5 mRNA expression in all samples tested, whereas CYP3A4 mRNA was not detectable, suggesting that CYP3A5 is the major CYP3A protein in human oesophagus. There were significant interindividual variations in the amount of proteins, ranging from 8-fold for CYP4A to 43-fold for CYP2E1. For each patient, data on exposure to risk factors for oesophageal cancer were available, including tobacco smoke, alcohol, gastro-oesophageal reflux and hot beverage consumption. None of these risk factors or other patient characteristics (age, sex, tumour location and tumour stage) were correlated with the protein level of the individual CYP enzymes as determined by quantitation of immunoblot staining. However, the small series of samples precludes any strong conclusion concerning the lack of such correlations. There were no differences between squamous cell carcinomas and adenocarcinomas in either the qualitative or quantitative expression of the CYP enzymes. These data demonstrate that a range of CYP enzymes are expressed in human oesophageal mucosa and indicate that this tissue has the capacity to activate chemical carcinogens to reactive DNA binding metabolites.

Sequential changes in cadherin-catenin expression associated with the progression and heterogeneity of primary oesophageal squamous carcinoma.

Maintenance of an adhesive function for cadherins requires appropriate membranous cellular expression and intact cadherin-catenin complexes. In normal squamous mucosa of the oesophagus there is membranous co-expression of E- and P-cadherin (E-cad, P-cad) in the basal compartment, whereas suprabasal stratification is associated with preservation of E-cad expression but loss of P-cad. Immunohistochemical staining of squamous dysplasia/carcinoma in situ shows a striking increase in the proportion of cells within the epithelial compartment showing co-expression of E- and P-cad with strong appropriate membranous expression of beta and gamma catenin. Strong membranous co-expression of E- and P-cad and beta catenin is seen on keratinocytes at the periphery of islands of invasive better-differentiated squamous carcinoma with keratinisation, mimicking normal mucosa. Beta catenin may be phosphorylated with implied loss of cadherin binding. Membranous cadherin and catenin expression is significantly down-regulated in poorly differentiated squamous carcinoma. No beta catenin mutations were demonstrated in squamous carcinomas following DNA extraction and sequencing, nor was any nuclear cadherin seen. Changes in cadherin-catenin complexes with cellular phenotype is well demonstrated in spindle cell carcinomas with a shift of cadherin expression from membranous to cytoplasmic between the epithelioid and spindle cell components of the tumour and with loss of expression in the sarcomatoid elements. In conclusion, we demonstrate an increased expression of P-cadherin early in tumourigenesis with loss of cadherin-catenin complexes in poorly differentiated invasive carcinomas. Cadherin/catenin expression may govern both the phenotype and biology of oesophageal squamous carcinomas.

Distinct regions of frequent loss of heterozygosity of chromosome 5p and 5q in human esophageal cancer.

Loss of heterozygosity (LOH) studies reported thus far suggest that tumor suppressor loci on chromosome 5q are important in esophageal cancer (EC) while little is known about the involvement of chromosome 5p. To investigate the potential existence of tumor suppressor gene(s) on chromosome 5 contributing to the development of EC, we performed LOH studies using a total of 24 polymorphic markers spanning the entire chromosome 5. Seventy primary esophageal cancers were microdissected and allelic deletions were detected by polymerase chain reaction (PCR)-single strand conformation polymorphism or by microsatellite analysis. LOH was observed in at least 1 of the loci in 47 of 70 (67%) esophageal tumors. Initially, 40 tumors [24 squamous cell carcinomas (SCC) and 16 adenocarcinomas (ADC)], each with matched histologically normal esophageal mucosa, were analyzed at 15 marker loci on 5p and 5q. A novel locus, D5S667 on 5p15.2, exhibited the highest frequency of LOH (44%) in these tumors along with another previously reported region of frequent deletion, irf-1 (5q31.1). In a series of 30 additional EC tumors (11 SCC and 19 ADC), a detailed LOH analysis of chromosome 5p15.2 region was conducted using 10 additional polymorphic markers, which mapped the frequently deleted region within 1 cM. Overall, LOH at the D5S667 locus was observed more frequently in SCC than in ADC (62% vs. 23%, p = 0.01). This significant rate of LOH of a distinct region of chromosome 5p implicates the existence of a putative tumor suppressor gene locus involved in EC.

p53 alterations in oesophageal cancer: association with clinicopathological features, risk factors, and survival.

AIM: To characterise the spectrum of p53 alterations (gene mutations and protein accumulation) in a consecutive series of surgically resected oesophageal cancers, and to evaluate associations with clinicopathological findings (age, sex, tumour histology, grade, and stage), potential risk factors (alcohol, tobacco, hot beverage consumption, history of gastrooesophageal reflux disease and antacid use), and survival. METHODS: The case series comprised 61 sequentially accrued patients with primary oesophageal carcinomas. Genomic DNA was extracted from banked (frozen) tumours and matched normal mucosal tissue; p53 mutations (exons 4-10) were studied by means of polymerase chain reaction (PCR)/single strand conformation polymorphism (SSCP) analysis and DNA sequencing. Immunohistochemistry (DO7, CM1) was used to assess cell nuclear p53 protein accumulation. Risk factor data, overall and disease free survival were measured prospectively, and analysis was carried out at the univariate level using Kaplan-Meier survival curves with log rank tests, and in multivariate analysis using Cox's proportional hazards models (parsimonious and fully adjusted). RESULTS: p53 mutations were found in 59% (36 of 61) and p53 protein accumulation was detected in 39% (24 of 61) of oesophageal cancers. Eighty eight per cent (23 of 26) of poorly differentiated tumours had p53 alterations compared with 57% (20 of 35) of moderate/well differentiated tumours (odds ratio (OR) = 5.575; p = 0.013). p53 mutations increased significantly with increasing consumption of hot beverages (measured by the average temperature of beverage, number consumed daily, and an index made by multiplying the two variables together) using both univariate (OR = 18.6; p = 0.0025) and multivariate (OR = 24.5; p = 0.0025) analysis. p53 alterations were associated with reduced disease free and overall survival (p = 0.051, log rank), with a univariate (unadjusted) hazard ratio (HR) of 2.241 (95% confidence limits (CL) = 0.973, 5.159; p = 0.058) for overall survival. By multivariate analysis adjusted for other relevant variables, the HR for tumours with p53 alterations was estimated at 2.913 (95% CL = 1.069, 7.936; p = 0.036) for overall survival. CONCLUSIONS: This study reports novel p53 mutations (exon 10), and an association between increasing consumption of hot beverages as a risk factor for p53 mediated oesophageal cancer. p53 is a potentially useful prognostic marker in this disease.

A phase II trial of preoperative mitomycin, cisplatin and 5-fluorouracil in adenocarcinoma of the oesophagus.

The effect of neoadjuvant chemotherapy in patients with apparently operable adenocarcinoma of the oesophagus has been investigated. Two courses of mitomycin, cisplatin and 5-fluorouracil (MCF) were given, followed by a radiological evaluation of response. Twenty-two of 25 patients completed both courses. Two showed a complete response and 12 a partial response. There was a pathological complete response of the primary tumour in only one patient (although there was residual secondary tumour in a local lymph node). The main toxicity was myelosuppression, with 9/22 patients having the second chemotherapy course delayed. There were three sudden deaths, one due to a pulmonary embolus and two due to complications of infections. Twenty-one patients underwent surgical exploration; there were 18 resections. Although the radiological response rate of MCF (14/25; 56%; 95% CI 37-75) appeared promising, there were no pathological complete responders. Further Phase II trials are needed to identify more efficacious agents and regimens that will yield a pathological response rate of at least 10%, before proceeding to randomized trials of neoadjuvant chemotherapy for adenocarcinoma of the oesophagus.

ras mutation and expression of the ras-regulated genes osteopontin and cathepsin L in human esophageal cancer.

As part of our ongoing studies to characterize molecular alterations in a well-defined series of surgically resected esophageal cancers, we examined the expression of 2 ras-regulated genes, whose products (osteopontin and cathepsin L) previously were shown to be associated with tumor invasion and metastasis. RNA was extracted from primary esophageal tumors (adenocarcinomas, 19; squamous-cell carcinomas, 6) and matched histologically normal esophageal mucosa from the distant resection margin. Northern analysis was used to quantitate RNA, relative to an 18S rRNA control, and immunohistochemistry to assess the tissue distribution of osteopontin. In addition, H-, K- and N-ras mutations were studied in the same tissues using PCR and hybridization with allele (mutant)-specific oligonucleotide probes. We demonstrated a K-ras mutation (codon 12, GTT) in one esophageal adenocarcinoma. The ras-regulated gene osteopontin was over-expressed in 100% of squamous-cell carcinomas and in 58% of adenocarcinomas relative to matched normal esophageal mucosa. Patterns of immunoreactivity for osteopontin protein also varied between squamous-cell carcinomas (tumor cell staining) and adenocarcinomas (predominantly tumor-infiltrating macrophages). Expression of cathepsin L also varied with esophageal tumor histology, with over-expression in 58% of primary esophageal adenocarcinomas and 33% of squamous-cell cancers.

Flow cytometry in squamous cell esophageal cancer and precancerous lesions.

Flow cytometry has also been used to study the nuclear DNA content (ploidy) and cell cycle kinetics of esophageal cancers. Studies of limited numbers of patients with Barrett's esophagus undergoing endoscopic surveillance suggested that aneuploidy may be a useful marker to identify subsets of patients at increased risk for malignancy. Few studies to date have evaluated premalignant tissues associated with the development of squamous-cell cancer of the esophagus. The present retrospective study comprises 80 surgical specimens of squamous-cell carcinoma of the esophagus from a high-incidence region of Thailand. All patients had surgery at the Department of Surgery, Prince of Songkla University, between March 1983 and December 1993. Sets of serial sections were cut every 0.5 cm starting from the proximal margin and down to the distal margin, and histopathology was confirmed to flow cytometric parameters (DNA content, S-phase fraction). Aneuploidy was found in 84% of squamous-cell carcinoma, 22.2% of carcinoma in situ, 28.6% of severe dysplasia, 11.0% of moderate dysplasia and 0% of mild dysplasia and normal esophageal mucosa specimens. The percentage was higher according to the level of severity or dysplasia. S-phase fraction was found to be 21.0 +/- 0.9% in squamous-cell carcinoma, 20.3 +/- 10.3% of carcinoma in situ, 20.9 +/- 5.3% of severe dysplasia, 12.9 +/- 9.7% of moderate dysplasia 7.6 +/- 0.8% of mild dysplasia and 8.9 +/- 3.2% of normal tissue. Similarly, the percentage of S-phase fraction tends to be higher according to the level of severity or dysplasia. These findings demonstrate that the aneuploidy and percentage of S-phase fraction tend to correlate with progression of esophageal premalignant tissues to invasive carcinoma. These measures may be clinically useful to identify patients at increased risk for esophageal malignancy.