Author/Editor		Dragosics, Brigitte
Title		Helicobacter pylori inflammation and gastric MALT lymphoma
Type		članek
Source		Gastroenterolog
Vol. and No.		Letnik 9, št. 20
Publication year		2005
Volume		str. 86-8
Language		eng
Abstract		Half a century ago, Denis Burkitt's report of a lymphoma of the jawbone in an African boy has been the first one about an infection associated human tumor in the history of medicine. Some decades later primary gastric lymphoma of the mucosa associated lymphoid tissue has been found to be closely associated to Helicobacter pylori (Hp) infection of the gastric mucosa. Moreover, early stages of lymphoma have been shown to completely regress after antibiotic eradication of the bacterium, thus, providing strong evidence for a causal role of Hp in lymphomagenesis. The oncogenetic pathways, first, from infectious gastritis to "early" lymphoma and, second, from Hp dependency of lymphomatous proliferation to autonomous tumor growth are poorly understood. However, some more examples of infection associated lymphomas are presented suggesting mechanisms like (i) tissue transformation to "altered self" creating new epitops for immunoresponse (ii) enhancement of autoimmunoreactivity (iii) production of idiotypic immunoglobulins and (iv) T cell directed specific B-cell proliferation with consecutive selection of a tumor clone. In contrast to Hp associated gastric carcinogenesis, the main pathways to Hp associated gastric MALT lymphoma may be determined by the immunoresponse with features of autoimmunoreactivity of the host combined with the Hp straininduced release of highly genotoxic oxygen reactive species from neutro philic leukocytes in the gastritis inflammatory infiltration.
Descriptors		HELICOBACTER PYLORI STOMACH NEOPLASMS LYMPHOMA, MUCOSA-ASSOCIATED LYMPHOID TISSUE AUTOIMMUNITY