Enhanced expression of cyclooxygenase-2 and nuclear beta-catenin are related to mutations in the APC gene in human colorectal cancer.

Mutational inactivation of the human tumour suppressor gene adenomatous polyposis coli (APC) results in constitutive activation of beta-catenin/T cell factor-4 (Tcf-4) mediated transcription of target genes. Up-regulation of cyclooxygenase-2 (COX-2) protein is frequently found in human colorectal cancer (CRC). We analysed 38 CRC for mutations in APC and beta-catenin and found an association between APC mutations and elevated COX-2 levels. Furthermore, APC mutations were predominantly observed in tumour tissues from the rectum compared to tumours of colonic origin. Western blot analysis revealed that nuclear beta-catenin levels were generally higher in tumours with APC mutations compared to tumours with wild type APC. However, there was also a higher level of nuclear beta-catenin in tumour compared to normal tissue, but nuclear Tcf-4 protein was constitutively expressed in tumour and normal tissue and showed no differences. An identified putative Tcf-4 binding element in the COX-2 promoter may partly explain the enhanced level of COX-2 and support the idea that COX-2 may be a downstream target of the APC/beta-catenin/Tcf-4 pathway.

Decreased levels of precursor transforming growth factor beta1 in human colorectal cancer.

Transforming growth factor (TGF) beta1 is a growth factor with wide-ranging effects on proliferation, differentiation, immunosuppression, apoptosis and matrix remodelling. TGFbeta1 seems to have an antitumorigenic role in the gastrointestinal tract but may also be associated with the development of colorectal cancer. Initially, TGFbeta1 is produced in a latent (precursor) form in epithelial cells and then is activated by a not clearly understood multistep process. In this study, we analysed precursor TGFbeta1 protein expression (n=40) and TGFbeta1 gene expression (n=49) in human colorectal adenocarcinomas and 49 normal adjacent tissue. Out of these 49 normal tissues 40 were matched. Western blot analysis revealed that the precursor TGFbeta1 protein levels were generally lower in colorectal cancerous tissue compared to adjacent non-cancerous tissue (P<0.001). Furthermore, with real-time PCR our results cannot reflect a statistically significant difference in TGFbeta1 gene expression between the tumour tissue and normal tissue. These finds indicate that it is likely that there are mechanisms which control precursor TGFbeta1 protein expression by factor(s) at the level of pre-translation of the TGFbeta1 transcript and/or at the level of post-translation of the TGFbeta1 protein in the tumours. This process may be related to carcinogenesis and poses the question whether the suppression of the precursor TGFbeta1 is an early event, in vivo, in the human colorectal adenoma-carcinoma sequence.

Why does the clinical diagnosis fail in suspected appendicitis?

OBJECTIVE: To identify systematic errors in surgeons' estimations of the importance of diagnostic variables in the decision to explore patients with suspected appendicitis. DESIGN: Prospective case series. SETTING: Two emergency departments, Sweden. PATIENTS: 496 patients with suspected appendicitis on admission, of whom 194 had a correct operation for appendicitis and 59 had a negative exploration. MAIN OUTCOME MEASURES: Predictors of a negative exploration expressed as the odds ratio (OR) for negative exploration. Variables influence on the decision to operate, expressed as the OR for operation, compared with the true diagnostic importance, expressed as the OR for appendicitis. RESULTS: Predictors of negative explorations were high ratings in variables describing pain and tenderness (patient's perceived pain, abdominal tenderness, rebound tenderness, guarding or rectal tenderness), weak or absent inflammatory response, female sex, long duration of symptoms and absence of vomiting, with OR of 1.8-3.0. Pain and tenderness had too strong an influence on the decision to operate whereas the lack of an inflammatory response, no vomiting, and long duration of symptoms were not given enough attention. There was no sex difference in the proportion of patients with non-surgical abdominal pain (NSAP) who were operated on, but NSAP was more common and appendicitis less common among women, leading to a larger proportion of negative appendicectomies among women. CONCLUSION: Negative explorations in patients with suspected appendicitis are related to systematic errors in the clinical diagnosis with too strong an emphasis on pain and tenderness, and too little attention paid to duration of symptoms and objective signs of inflammation. Rectal tenderness is not a sign of appendicitis. The risk of diagnostic errors is similar in men and women.

Repeated clinical and laboratory examinations in patients with an equivocal diagnosis of appendicitis.

In-hospital observation with repeated clinical examinations is commonly used in patients with an equivocal diagnosis of appendicitis. It is not known if repeated measurements of temperature and laboratory examinations have any diagnostic importance in this situation. The importance of repeated measurements of the body temperature, white blood cell (WBC) and differential cell counts, C-reactive protein concentration (CRP) and of the surgeon's repeated assessments was prospectively analyzed in 420 patients with an equivocal diagnosis of appendicitis at admission who were reexamined after a median of 6 hours of observation. The final diagnosis was appendicitis in 137 patients. After observation the inflammatory response was increasing among patients with appendicitis and decreasing among patients without appendicitis. The variables discriminating power for appendicitis consequently increased, from an area under the receiver operating characteristic (ROC) curve of 0.56 to 0.77 at admission, to 0.75 to 0.85 after observation. The ROC area of the surgeons' clinical assessment increased from 0.69 to 0.89. The WBC and differential cell counts were the best discriminators at the repeat examination. The change in the variables between the observations had weak discriminating power and had no additional importance in addition to the actual level at the repeat examination. To conclude, the diagnostic information of the temperature and laboratory examinations increased after observation. Repeated controls of the body temperature and laboratory examinations are therefore useful in the management of patients with equivocal signs of appendicitis, but the result of the examinations must be integrated with the clinical assessment.

Differential expression of cyclooxygenase 2 in human colorectal cancer.

BACKGROUND: Experimental, clinical, and epidemiological studies have implicated mitogenic metabolites of arachidonic acid such as prostaglandin E(2) (PGE(2)) in colorectal carcinogenesis. Recently, cyclooxygenase 2 (COX-2) which catalyses the conversion of arachidonic acid to PGE(2), has displayed increased levels in human colorectal cancer. AIMS: To evaluate whether there is differential COX-2 expression from different locations (caecum, ascending, transverse, descending, or sigmoid colon, and rectum) in human colorectal cancer. METHODS: Protein levels of COX-2 were determined by western blot analysis in tumours and adjacent normal mucosa of 39 patients with colorectal cancer. RESULTS: There was a notable overexpression of COX-2 protein in tumours located in the rectum (p<0.001) compared with other locations in the colon. Rectal tumours revealed elevated COX-2 protein levels in 18/20 cases compared with 4/19 colonic cases. No association between enhanced COX-2 protein expression in tumour tissue and Dukes's stages was found. CONCLUSIONS: Results suggest that the differential COX-2 expression may be due to differences in gene regulatory factors affecting COX-2 expression and/or reflect secondary changes in tumour progression which may have clinical implications.

Diagnostic value of disease history, clinical presentation, and inflammatory parameters of appendicitis.

The clinical diagnosis of appendicitis needs to be improved, as up to 40% of explorations for suspected appendicitis are unnecessary. The use of body temperature and laboratory examinations as diagnostic aids in the management of these patients is controversial. The diagnostic power of these variables compared to that of the disease history and clinical findings is not well studied. In this study we prospectively assessed and compared the diagnostic value of 21 elements of the history, clinical findings, body temperature, and laboratory examinations in 496 patients with suspected appendicitis. The diagnostic value of each variable was compared from the area under the receiver operating characteristic (ROC) curve and the likelihood ratios (LR). Logistic regression was used to analyze the diagnostic value of a combination of variables and to analyze independent relations. No single variable had sufficiently high discriminating or predicting power to be used as a true diagnostic test. The inflammatory variables (temperature, leukocyte and differential white blood cell (WBC) counts, C-reactive protein) had discriminating and predicting powers similar to those of the clinical findings (direct and rebound abdominal tenderness and guarding). Anorexia, nausea, and right-sided rectal tenderness had no diagnostic value. The leukocyte and differential WBC counts, C-reactive protein, rebound tenderness, guarding, and gender were independent predictors of appendicitis with a combined ROC area of 0. 93 for appendicitis. This showed that inflammatory variables contain important diagnostic information, especially with advanced appendicitis. They should therefore always be included in the diagnostic workup in patients with suspected appendicitis.

Gene expression of cyclooxygenase-2, group II and cytosolic phospholipase A2 in human colorectal cancer.

The development of intestinal tumours in the Min mouse is influenced by Moml locus, where the group II phospholipase A2 (PLA2-II) gene has been suggested as the candidate gene. Since no causative genetic alterations have been identified in PLA2-II in human colorectal tumours, we tested whether PLA2-II or the cytosolic isoform cPLA2, are dysregulated in human colorectal carcinogenesis. By means of RT-PCR, the expression of these genes and cyclooxygenase-2 (COX-2), which is upregulated in colorectal tumours, were examined. No changes in gene expression of PLA2-II were found in 44 tumours compared to normal mucosa. cPLA2 and COX-2 were upregulated; however, no correlation in expression was found between these genes. Thus, the supply of arachidonic acid provided by PLA2-II/cPLA2 seems not to be the rate limiting step in PGE2 (a prostaglandin/mitogen) formation via COX-2 and PLA2-II plays a minor or no role in human colorectal carcinogenesis.

Clusters of acute appendicitis: further evidence for an infectious aetiology.

BACKGROUND: The aetiology of appendicitis, the commonest cause of acute abdomen, is unknown. Infection has been proposed but the evidence has been unconvincing. The purpose of the present study was to investigate if temporo-spatial clustering and outbreaks, characteristics of infectious diseases, could be found in appendicitis cases in a defined Swedish population. METHODS: Temporo-spatial clustering among 1155 cases from three districts of Jönköping County in 1984-1990 was identified by Knox space-time cluster analysis. Outbreaks were identified by retrospective study of temporal variations in 3590 consecutive cases of acute appendicitis from the city of Jönköping in 1969-1990. RESULTS: Space-time clustering was found among patients with operations less than 60 days apart (observed/expected [O/E]-ratio 1.46, P = 0.016). Subset analysis revealed clustering to be commonest among patients from the same households (O/E-ratio 6.52, P = 0.012), among patients younger than 15 years (O/E-ratio 3.61, P = 0.004) and among females (O/E-ratio 2.28, P = 0.004). Three outbreaks with a significantly increased number of cases were observed during the 22-year study period (O/E-ratio 1.6-2.2, P = 0.001-0.049). CONCLUSIONS: The finding of temporo-spatial interaction and outbreaks among appendicitis cases supports the concept that appendicitis may be caused by infectious agents.

Indications for operation in suspected appendicitis and incidence of perforation.

OBJECTIVE: To clarify poorly understood epidemiological features of appendicitis. DESIGN: Retrospective study of consecutive cases from a defined population and analysis of data from published studies. SETTING: County of Jönköping, Sweden. 3029 patients who underwent operation in 1984-9 and 4717 patients from the county town who underwent operation in 1970-89, all for suspected appendicitis, plus 48,426 cases from six reported studies. MAIN OUTCOME MEASURES: Incidences specific for age and sex and temporal trends of perforating and non-perforating appendicitis and removal of a normal appendix. Associations between diagnostic accuracy, rate of perforation, and incidences of removal of a normal appendix and of perforating and non-perforating appendicitis. RESULTS: The incidence of appendicitis was 116/100,000 inhabitants. Appendicitis was more common in male patients. The incidence of perforating appendicitis was independent of age, stable over time, and uninfluenced by the rate of laparotomy, whereas the incidence of non-perforating appendicitis was age dependent, decreasing over time, and related to the diagnostic accuracy and rate of removal of a normal appendix. CONCLUSIONS: Perforating and non-perforating appendicitis seem to be separate entities, and appendicitis that resolves spontaneously is common. This may have important implications for managing suspected appendicitis.

Diagnostic accuracy and perforation rate in appendicitis: association with age and sex of the patient and with appendicectomy rate.

OBJECTIVE: To see if diagnostic accuracy and perforation rate in acute appendicitis is associated with age and sex of the patients and with the appendicectomy rate. DESIGN: Retrospective study of consecutive patients from a defined population. Study of associations between diagnostic accuracy and perforation rate and appendicectomy rate in published reports. SETTING: Jönköping county, Sweden. SUBJECTS: 3,029 patients operated on for suspected acute appendicitis from 1984-1989. MAIN OUTCOME MEASURES: Findings at laparotomy for acute appendicitis, confirmed with histological examination in 83% of the cases. RESULTS: Diagnostic accuracy was low at the extremes of age and in women (60% compared with 79% in men, p less than 0.001). When all intra-abdominal conditions were considered the percentage of negative laparotomies among women (24%) was twice that among men (12%, p less than 0.001). This difference between the sexes was also seen in nonfertile ages. Perforation rate was higher among men (18% compared with 13%, p less than 0.01) and at extremes of age. According to correlation analysis of published reports the perforation rate is unrelated to either diagnostic accuracy or appendicectomy rate while diagnostic accuracy is inversely associated with the appendicectomy rate. CONCLUSION: A low diagnostic accuracy is a problem mainly at extremes of age and in females. A low appendicectomy rate is associated with a high diagnostic accuracy, while the perforation rate is unaffected. A conservative attitude to exploration therefore seems justified.

Beta-blockade during whole-body hyperthermia: a toxicity study in the dog.

A radiant heat device (RHD) for whole-body hyperthermia (WBH) has been safely and effectively used with a dog model. The cardiovascular changes which occur in the dog during WBH--including heart rate, blood pressure, cardiac output, stroke volume and ejection fraction--agree qualitatively and quantitatively with changes observed in previous WBH-RHD studies done in pigs and humans. We elected to study the effect of propanolol in dogs during WBH in order to evaluate this drug's potential use in human cancer patients who are ineligible for WBH because of coronary artery disease. This report details cardiovascular changes which occur with beta-blockade during 42 degrees C WBH in the dog. Our results show that the level of beta-blockade needed to control heart rate during WBH produces acute cardiovascular decompensation.

Whole body hyperthermia in the treatment of neoplastic disease.

Hyperthermia, the elevation of body or tissue temperature, has been used to treat various ailments including cancer since ancient times. During the past 15 years, laboratory evidence has developed to provide a scientific rationale for its use in the treatment of neoplastic diseases. Generally, temperatures in excess of 41 degrees C in vitro will kill neoplastic cells exponentially as a function of time. The direct cytotoxic effects of heat alone, however, may have limited clinical utility due to poor response rates and response durations. The greatest potential of hyperthermia resides in its use as an adjunct to other forms of therapy. As hyperthermia is nonmyelosuppressive and can potentiate the tumoricidal effects of radiation, chemotherapy, and immunotherapy, its use as part of a multimodality treatment approach is attractive. Three forms of hyperthermia have been developed for clinical application: local, regional, and whole body. As WBH addresses the issue of cancer as a systemic disease, it has perhaps the greatest potential for curative success when used as an adjunct to other therapeutic modalities. Using a variety of WBH methodologies, core temperatures have been maintained at 41 degrees C or 42 degrees C in humans for several hours with variable morbidity and occasional mortality. Most systems for WBH include a requirement for general anesthesia, as well as complex equipment to regulate patient temperature. The system most used to date worldwide is based on extracorporeal heating. A hot water suit system, developed at the National Cancer Institute, has also undergone extensive testing.(ABSTRACT TRUNCATED AT 250 WORDS)

Design and test of microwave interstitial applicators with improved longitudinal heating pattern.

A microwave applicator for interstitial hyperthermia was designed for use in conjunction with interstitial radiation therapy. Measurements were performed in phantom material and in the hind legs of anaesthetized pigs. In both studies two applicators were inserted in parallel at a distance of 2 cm and to a depth of 6 cm. The temperature distribution produced by two conventional applicators were compared with the temperature distribution produced by two applicators of the new design. Improvement of the heating pattern was found in both phantom and animal studies; the heating pattern produced by the new applicators was shifted towards the tip. This may be of clinical importance as heating can be achieved without applicator penetration through tumour tissue into normal tissue.

Phase I trial of lonidamine with whole body hyperthermia in advanced cancer.

Lonidamine is a dechlorinated derivative of indazole-3-carboxylic acid which preclinically synergizes with hyperthermia. Clinically, this nonmyelosuppressive drug (given p.o. daily) is active as a single agent in a variety of malignancies. On this basis, a Phase I study which incorporates a drug escalation schema as well as an escalation in temperature, i.e., 41.0 degrees C for 85 min to 41.8 degrees C for 75 min, was executed. Induction therapy included seven whole-body hyperthermia treatments. Whole-body hyperthermia was delivered using a radiant heat system. Twenty-four patients were entered on study. Of these, 20 were evaluable for response. Group A (60 mg/m2) had three patients with three no responses. Group B (180 mg/m2) consisted of three patients: one lymphoma, partial response; two gastrointestinal adenocarcinomas, one partial response and one improvement, i.e., less than a partial response. Group C (360 mg/m2) had 17 patients: two lung cancers, one complete response and one improvement; one melanoma, improvement; one ovarian, disease stabilization (greater than 100 days); two adenocarcinomas of the gastrointestinal tract, two disease stabilizations; 11 patients, no responses; one patient entered at this level was ineligible for study and did not receive lonidamine. Therapy was well tolerated. Of 16 patients reporting myalgias, two required a lonidamine dose reduction; one patient required dose reduction for central nervous system toxicity. Results obtained encourage Phase II clinical trials.

A pilot study of whole body hyperthermia and local irradiation for advanced non-small cell lung cancer confined to the thorax.

Six patients with Stage III non-small cell lung cancer completed therapy which consisted of 4 whole body hyperthermia (WBH) treatments during the first 2 weeks of a 6 week course of radiotherapy (60 Gy). A radiant heat system was used to deliver the 41.8 degree C WBH. To reduce the danger of transverse myelitis, the spinal cord (and therefore part of the mediastinum and contralateral hilar region) was not irradiated during the first 2 weeks of radiotherapy and concurrent WBH. Subsequent treatments (weeks 3-6) included conventional irradiation to the primary tumor, mediastinal lymph nodes and spinal cord. Areas of gross disease responded to therapy in 5/6 patients. No radiation pneumonitis was observed. In 2/6 patients, relapse (after 10 months and 6 months, respectively) occurred with malignant pericardial effusions. The mediastinum in these patients was not an area of bulky disease involvement initially. To eliminate such WBH-radiation sanctuary zones, the protocol was modified to include greater combined WBH-radiation treatment. This is accomplished by having one WBH treatment "sandwiched" between 2 radiation fractions. The preclinical basis for the revised protocol is presented.

Temperature distribution during radiant heat whole-body hyperthermia: experimental studies in the dog.

A radiant heat system for whole-body hyperthermia (WBH) has been safely and effectively used in mice, pigs and humans. This report details our adaptation of this methodology to dogs. Mongrel dogs were used to study different anaesthesia methods including spontaneous ventilation with or without intubation, as well as mechanical ventilation. Temperature distribution was studied during 42 degrees C WBH; intraabdominal, liver, bone marrow, brain, rectal, lung, oesophageal and skin temperatures were monitored. When a target temperature of 42 degrees C was achieved, temperature gradients between organs were minimal with the possible exception of bone marrow. Results obtained are consistent with the concept that the liver is a major source of metabolic heat production. The establishment of a dog model for WBH allows for physiological and pharmacological studies. The existence of spontaneous neoplasms should promote the use of this species for trials combining hyperthermia with other modalities.

Effects of local microwave hyperthermia and 5-fluorouracil in treatment of experimental liver cancer.

The effect of combined treatment with local hyperthermia and i.v. infusion of 5-fluorouracil was studied in 39 Wistar rats with a transplanted adenocarcinoma inoculated in the liver. Ten to 13 days later the rats were divided into three groups. Group A1 was subjected to local microwave hyperthermia (42 degrees C) for 1 h. During the hyperthermia, an i.v. infusion of 5-FU (20 mg/kg body weight) was given. In group A2 5-FU was administered under normothermic conditions. Group A3 received saline infusion under normothermic conditions. The mortality after infusion of 5-fluorouracil and hyperthermia increased during the first week after treatment. In group A1, a significant growth retardation of liver tumor was registered seven days after treatment. This effect was not superior to that of hyperthermia alone as previously described for the same experimental model. Studies of 5-FU pharmacokinetics in plasma were performed in another 20 Wistar rats. Ten rats were given an i.v. infusion of 5-FU during local hyperthermia, while the other 10 were infused under normothermic conditions. Plasma concentration of 5-FU was determined by isotachophoretic separation. The hyperthermia caused a faster decline in serum concentration of 5-FU, probably because of accelerated catabolism of the drug.