A small deletion in the 3′‐untranslated region of the cyclin D1/ PRAD1/ bcl‐1 oncogene in a patient with chronic lymphocytic leukemia

• Published in: International journal of cancer Vol. 76; no. 6; pp. 791 - 796
• Main Authors: Hosokawa, Yoshitaka, Suzuki, Ritsuro, Joh, Tatsuroh, Maeda, Yumiko, Nakamura, Shigeo, Kodera, Yoshihisa, Arnold, Andrew, Seto, Masao
• Format: Journal Article
• Language: English
• Published: New York Wiley Subscription Services, Inc., A Wiley Company 10.06.1998; Wiley-Liss
• Subjects: Base Sequence; bcl-1 gene; Biological and medical sciences; cyclin D1; Cyclin D1 - genetics; Gene Deletion; Genes, bcl-1; Hematologic and hematopoietic diseases; Humans; Leukemia, Lymphocytic, Chronic, B-Cell - genetics; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Medical sciences; Molecular Sequence Data; PRAD1 gene; RNA, Messenger - analysis; Human; Translocation; Chronic; Hairy cell leukemia; Lymphoproliferative syndrome; Chromosome 11; Deletion; Malignant hemopathy; Chromosome 14; Onc gene; Genetic determinism
• ISSN: 0020-7136; 1097-0215
• DOI: 10.1002/(SICI)1097-0215(19980610)76:6<791::AID-IJC4>3.0.CO;2-T

The cyclin D1/PRAD1 oncogene, a key regulator of the G1 phase of the cell cycle, has been incriminated in the pathogenesis of human neoplasia. Cyclin D1 was also demonstrated to be identical to the long‐sought bcl‐1 oncogene in B‐cell malignancies with the t(11;14)(q13;q32) translocation. We report here a small deletion in the 3′‐untranslated portion of the cyclin D1 gene in leukemia cells of a patient diagnosed with B‐chronic lymphocytic leukemia (CLL), associated with overexpression of the corresponding cyclin D1 mRNA. During a Northern blot survey of B‐cell malignancies, we identified a patient whose CLL cells showed a marked increase in 1.5–1.6 kb cyclin D1 mRNA species. Subsequent Southern blot analysis showed that genomic DNA from the patient's cells contained an extra band in the EcoRI digest, suggesting that one allele of the cyclin D1 gene may be altered. Polymerase chain reaction (PCR) analysis of the genomic DNA and direct DNA sequencing clearly disclosed that one allele of the cyclin D1 gene was deleted in the 3′‐untranslated region, which would contribute to an increased stability of its mRNA. Reverse transcription‐polymerase chain reaction (RT‐PCR) analysis and direct DNA sequencing revealed that the cyclin D1 mRNA was deleted at the corresponding region. This finding provides further evidence for a critical role of cyclin D1 in the pathogenesis of B‐cell malignancies and highlights a novel mechanism, a small deletion in the 3′‐untranslated region, responsible for deregulation of the cyclin D1 gene in oncogenesis. Int. J. Cancer 76:791–796, 1998.© 1998 Wiley‐Liss, Inc.