The early diagnosis of mesothelioma, an aggressive malignant tumor, is considered to be important for prognosis. X-ray is commonly used for the assessment of a mass in a population exhibiting a risk factor. However, there are currently no available studies indicating that such an assessment may be used to achieve early diagnosis and improve the patient's outcome. We previously reported that N-ERC/mesothelin may be a useful blood tumor marker for mesothelioma. In order to investigate whether this tumor marker is useful for early diagnosis in a mass examination, in 2007 we initiated a 5-year large-scale screening of construction workers with a risk of asbestos exposure in Japan. Blood samples were collected annually and N-ERC/mesothelin levels were determined. Based on the results of those findings, along with medical history and related data, we screened the participants to identify a high-risk population. As a result, 62 subjects were identified among ~40,000 participants as the high-risk population. Two of these 62 participants subsequently developed mesothelioma, although the remaining participants have not yet developed mesothelioma. In conclusion, N-ERC/mesothelin may be useful as a blood tumor marker in the early diagnosis of mesothelioma in a mass examination. A future prospective study to confirm the findings of this research screening is currently under planning.

Abstract. a large-scale screening involving the measurement of n-Erc/mesothelin levels in blood using an EliSa system for the early diagnosis of malignant mesothelioma (mm) was carried out in individuals with a history of employment at construction sites. approximately 30,000 subjects were screened. Of the 80 subjects with high-risk values, one male patient was diagnosed as having mm based on a pEt study and histopathology. This is the first report of the pre-clinical diagnosis of mm based on blood test screening. in addition, plasma levels of n-Erc/mesothelin may be effectively used for monitoring relapse after surgery. Introductionmesothelioma is an aggressive tumor arising from the mesothelium, a membrane lining various body cavities, including the pleura, peritoneum and pericardium, and is usually associated with asbestos exposure. due to the long incubation period and the short survival time after the onset of asbestos-induced malignant mesothelioma (mm), an early diagnostic system for individuals with a history of asbestos exposure is critically required. recently, soluble mesothelin-related protein (1) and serum mesothelin have been reported to be potentially useful markers for the early diagnosis of mm (2,3). a 71-kda precursor protein of human Erc/mesothelin can be cleaved into a 40-kda c-terminal fragment as a surface Gpi-anchored glycoprotein and a 31-kda n-terminal fragment as a secreted protein. We focused on this n-Erc/ mesothelin, as it is physiologically secreted into the blood, and as a specific ELISA system has been developed for N-ERC/ mesothelin (2,3).in the present study, to develop a pre-clinical diagnostic system for the early detection of mm, the levels of n-Erc/ mesothelin, the n-terminal 31-kda fragment of mesothelin, in blood samples was measured by EliSa as a primary screening method. chest radiography, chest ct and positron emission tomography (pEt) examinations, and also histopathology, were then used as secondary screening examinations for individuals with a history of exposure to asbestos and consequently, a high risk of developing of mm. Materials and methods Establishment of ELISA for N-ERC/mesothelin and measurement of blood samples.the sandwich EliSa system used in this report were established as described previously (3). the 7E7 moab was used as the capture antibody and the 16K16 moab was used as the detecting antibody after conjugation with horseradish peroxidase. recombinant n-Erc/mesothelin was used as the standard. the protein in the EliSa system was purified from culture supernatants of CHO-K1 cells transfected with Erc/mesothelin cdna using an anti-Erc/ mesothelin poab. Edta plasma was used for this EliSa.the present study was approved by the institutional review Board of Juntendo university School of medicine, its hospital and immuno-Biological laboratories. Written informed consent for participation in the study was obtained from all of the subjects. Results Case reports of three patientsPatient A: clinical history. the subject was a 71-year-old male who had a history...

The peroxide content of an oxidized oil is of limited value in estimating the toxicity of the oil, because some decomposition products of peroxides are also injurious to health. Methods of evaluating the toxicity of deteriorated fats and oils have been investigated. A method based on the mortality of chicken embryos following injection of oil into the yolk sac has been found to be much more sensitive and reproducible than tests based on growth rate of weanling rats or mice fed deteriorated oils. An enzyme activity method using alkaline phosphatase has been tested and gives promise of being very rapid, but additional work is required to evaluate this method and to look for better enzyme systems.