ABSTRACT
zone B cell lymphoma of mucosa-associated lymphoid tissue type according to the Revised European American Lymphoma classification). Other mucosa-associated lymphoid tissue-type lymphomas arise in the salivary glands, thyroid gland, and in the lung (bronchus-associated lymphoid tissue). Here, we report the first case of a monoclonal mucosa-associated lymphoid tissue lymphoma with simultaneous manifestation in the colonic and bronchial mucosa in a 62-year-old patient. With mitoxantrone, chlorambucil, and prednisone polychemotherapy, a complete year-long remission was achieved.
Subject(s)
Colonic Neoplasms/diagnosis , Lung Neoplasms/diagnosis , Neoplasms, Multiple Primary/diagnosis , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biopsy , Bronchoscopy , Cisplatin/administration & dosage , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , Colonoscopy , Humans , Intestinal Mucosa/pathology , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Male , Middle Aged , Mitomycins/administration & dosage , Neoplasm Staging , Neoplasms, Multiple Primary/drug therapy , Neoplasms, Multiple Primary/pathology , Vinblastine/administration & dosageABSTRACT
Regulated apoB degradation in HepG2 cells occurs in the endoplasmic reticulum (ER), is catalyzed by an N-acetylleucylleucylnorleucinal (ALLN)-sensitive proteinase, and generates a specific 70 kDa fragment (Adeli, K., 1994, J. Biol. Chem. 269, 9166-9175) [corrected]. In the present report, we have characterized the 70 kDa fragment by immunoprecipitation of permeabilized HepG2 cells with a battery of monoclonal antibodies against various sites on the apoB molecule. N-Terminal monoclonal antibodies (1D1 and 2D8) were capable of binding to the 70 kDa fragment suggesting that this polypeptide is an N-terminal fragment of the intact apoB. Subcellular fractionation of permeabilized cells and carbonate extraction resulted in the detection of the 70 kDa fragment in the ER lumen. Endoglycosidase H treatment confirmed that the fragment is N-linked glycosylated. We hypothesize that the ALLN-sensitive proteinase which may be located on the luminal side of the ER membrane, catalyzes an initial cleavage of apoB near the N-terminus generating a 70 kDa fragment, which is then released into the ER lumen.
