Epidermal growth factor receptor gene mutation, amplification and protein expression in malignant pleural mesothelioma
Wednesday, April 9th, 2008.
Journal of Cancer Research and Clinical Oncology. 2008 Apr 8 [Epub ahead of print] [Link]
Okuda K, Sasaki H, Kawano O, Yukiue H, Yokoyama T, Yano M, Fujii Y.
Department of Oncology, Immunology and Surgery, Nagoya City University Graduate School of Medical Science, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.
Abstract
Epidermal growth factor receptor (EGFR) is overexpressed in a variety of epithelial malignancies. In lung cancer cases, EGFR gene mutation at the kinase domain and EGFR gene amplification are reported to be predictors of the response to EGFR tyrosine kinase inhibitors. In malignant pleural mesothelioma (MPM), the role of EGFR is less clear. We studied EGFR gene mutation, amplification and protein expression in 25 Japanese patients with MPM. None had previously reported EGFR mutations detected by the TaqMan PCR assay. Using immunohistochemistry, 8/25 (32%) cases were positive for the EGFR protein. The cases of sarcomatous type and desmoplastic type were all negative. Fluorescence in situ hybridization analysis revealed three low polysomy cases and one high polysomy case. The low polysomy cases included one biphasic type and two epithelial
types, and the high polysomy case was epithelial type. These four cases expressed EGFR protein. In MPM, EGFR seems to play a role in a limited subset of patients. To identify possible candidates for EGFR tyrosine kinase in inhibitor therapy, the information on the EGFR gene status may be valuable.
Keywords: Malignant pleural mesothelioma, Epidermal growth factor receptor, Amplification, FISH, Immunohistochemistry
Glossary
- therapy
- any of the measures taken to treat a disease. Unproven therapy is any therapy that has not been scientifically tested and approved. Use of an unproven therapy instead of standard (proven) therapy is called alternative therapy. Some alternative therapies have dangerous or even life-threatening side effects. For others, the main danger is that a patient may lose the opportunity to benefit from standard therapy. Complementary therapy, on the other hand, refers to therapies used in addition to standard therapy. Some complementary therapies may help relieve certain symptoms of cancer, relieve side effects of standard cancer therapy, or improve a patient's sense of well-being. The ACS recommends that patients considering use of any alternative or complementary therapy discuss this with their health care team.
- oncology
- (on-call-o-jee) the branch of medicine concerned with the diagnosis and treatment of cancer.
- mutation
- a change; a change in a gene.
- in situ
- in place; localized and confined to one area. A very early stage of cancer.
- immunology
- (im-mune-ahl-o-jee) study of how the body resists infection and certain other diseases. Knowledge gained in this field is important to those cancer treatments based on the principles of immunology.
- gene
- a segment of DNA that contains information on hereditary characteristics such as hair color, eye color, and height, as well as susceptibility to certain diseases. Women who have BRCA1 or BRCA2 gene mutations (defects) have an inherited tendency to develop breast cancer.
- cancer
- malignancy; a group of diseases typified by abnormal, generally out-of-control, cell growth.
- mesothelioma
- a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.
- epidermal growth factor receptor
- The process of cell division, growth, differentiation and death is a highly regulated process. Several class of trans membrane receptors play a pivot role in this process, of these, epidermal growth factor receptor (EGFR) a member of Receptor Tyrosine Kinase (RTK) family are best known. These comprises of four receptors Erb B1/HER 1, Erb B2 / HER 2, Erb B3/ HER 3, and Erb B4 / HER 4. Of these HER 2 is the most favoured target. (Source: Manoj Pandey and K Chandramohan)

