Japanese researchers have recently investigated the mechanism of mesothelin gene that result in malignant mesothelioma. The study was published in the medical journal Human Pathology.
Mesothelioma is a rare cancer almost entirely caused by exposure to asbestos. Because there is no cure for this disease, life expectancy for most patients with mesothelioma ranges between four and 18 months after diagnosis of mesothelioma is known for sure. Although there is no cure to date, some mesothelioma patients who are diagnosed early can be a combination of aggressive therapies, such as surgery, chemotherapy and radiation. Combination therapy, known as multimodality therapy, currently has the best chance to extend the life of the patient.
Mesothelioma malignant cells
The study's authors explain, "Gene methylation led to the development of malignant tumors in some tumors [malignant mesothelioma] is histologically divided into 3 subtypes, namely, epithelioid, sarcomatoid, and biphasic type, and it shows that mesothelin expression is restricted to the type epithelioid and epithelioid components of biphasic type MM (malignant mesothelioma). However, the mechanism of regulation of expression has not been clarified. "
A total of 118 lung specimens examined, including 39 MM, 41 lung carcinomas, 26 nonneoplastic lung lesions, and 12 samples of normal lung tissue. Specimens were tested for mesothelin expression by immunohistochemistry test, along with the methylation status of 20 locations mesothelin gene promoter.
The results showed mesothelin is expressed in the epithelioid subtype of epithelioid and biphasic subtypes. However, mesothelin expression was not found either in the sarcomatoid subtype and sarcomatous part of the biphasic type. Mesothelin gene promoter have a significantly hypomethylasi on specimens without mesotehelioma malignant subtype when compared with other lung lesions, and examples of normal lung tissue.
The researchers concluded, "These findings suggest that hypomethylasi of mesothelin gene promoter may be specifically associated with the formation of MM, regardless of expression status, and that the mesothelin protein expression is lost in sarcomatoid type due to some posttranscriptional regulatory mechanisms are not known. "