Mesothelioma

Mesothelioma is a malignant neoplasm that develops from the mesothelium tissue (a membrane that covers the internal organs present in the body). It occurs very r arly and is more ofttimes agentd by inhaling asbestos dust. The incidence of the unhealthiness is slowly on the rise. In the US, virtually 2000 new cases are account every year. About 70 to 80% of all cases with mesothelioma report word-painting to asbestos (NCI, 2002). Mesothelioma can develop in various sites of the body including the pleura (membranes that covers the lungs), peritoneum (membrane that covers the abdominal cavity), tunica vaginalis testis (membrane that covers the male internal reproductive organs) and tunica serosa uteri (membrane that covers the feminine internal reproductive organs) (NCI, 2002).It is made up of one layer of matte or cuboidal jail kiosks that surround a particular organ or an organ set belonging to a particular group (Weitz & Luxenberg, 2006). In between these membranes a fluid is present that permits some amount of impetus during physiologic functioning. When the asbestos is inhaled, it nourishs deposited into parenchyma of the lungs from where it enters the immediate membrane that covers the lungs. It may be carried soon to the separate(a) membrane of the lung. The tumor usually begins as discrete plaques known as malignant mesothelial plaques (Weitz & Luxenberg, 2006).These discrete masses soon combine to form a large sheet like lesion that spreads. The exact mould by which mesothelioma occurs is not understood clearly, however, it seems that chronic irritation of the membrane plays a very beta role (Weitz & Luxenberg, 2006). The chromosomes present in the cell are distorted (Tan, 2007). matchless of the most frequent changes in the malignant cell was the loss of a copy of Chromosome 22.The chromosomal picture of the cell seems to be very daedal (complex karyotype) and is rearranged (Tan, 2007). Sometimes, the chromosome arms of 1p, 3p, 9p and 6 q may also get structurally rearranged. This may be brought about by close contact between the chromosomes or the structural proteins with the asbestos particles (Weitz & Luxenberg, 2006).The asbestos may get deposited in the peritoneum either through the lymphatic formation or the due ingestion of the sputum from the lungs (Weitz & Luxenberg, 2006). The long thin fibers of asbestos are more dangerous than the feathery fibers as they more easily cause malignant neoplastic disease. Once the fibers get deposited in the pleura, the cancer development process in truth begins. In experimental rats, it has been observed that when the pleura or the peritoneum are invaded by the asbestos particles, macrophages and the separate cells of the bodys defense mechanism accumulate (Weitz & Luxenberg, 2006).As the disorder progresses, the macrophages and immune cells continue to invade the lesion. Slowly the cells get transformed into malignancy. Studies deem demonstrated that the asbestos par ticles may directly (through physical inter legal action) and indirectly (through accumulation of macrophages) grow about malignant transformation of the epithelium cells. Indirectly, the macrophages begin to function vicariously. They scavenger cell the asbestos particles and release higher amounts of hydroxyl radicals.They may stimulate the cancer process by bear on the DNA present in the cell. Several other substances are released from the macrophages such as mitogens, growth factors, etc, which may bring about chronic irritation. They also alter entry of certain substances into the cell (by affecting the membrane) and reducing the effect of antioxidant action within the cells. Asbestos is also known to suppress the action of the bodys defense mechanism by overcoming the action of the lymphocytes (Weitz & Luxenberg, 2006).Several structural and functional features have been observed in the cells touch on with mesothelioma (which have asbestos particles within the cells) 1.th e suppressor genes against cancers present in the cells may get inactivated when the asbestos fibers enters the cells2.other cancer-stimulating agents may get activated and affect the cell3. the DNA of the cell gets altered due to the incorporation of a foreign DNA which encourages cancer formation4. the DNA repair enzymes may get stimulated and frequently result in a faulty method of repair5.the cell terminal processes may become abnormal resulting in immortality6.the DNA chronological sequence may be added at the ends of the cell which makes the cells immortal and results in abnormal functioning (Weitz & Luxenberg, 2006)ReferencesNCI. Mesothelioma Questions and Answers. 2002. NCI. 5 Apr. 2007 http//www.cancer.gov/cancertopics/factsheet/Sites-Types/mesotheliomaTan W.W. Mesothelioma. 2007. E-Medicine. 5 Apr. 2007 http//www.emedicine.com/med/topic1457.htmWeitz & Luxenberg. The Pathophysiology of Mesothelioma. 2006. Weitz & Luxenberg Inc. 5 Apr. 2007 http//www.weitzlux.com/mesothelio ma/Pathophysiology_403723.html