Cyclin D1/PRAD1/BCL-1 alternative transcript [B] protein product in B-lymphoid malignancies with t(11;14)(q13;q32) translocation.
The cyclin-D1/PRAD1 oncogene, a key regulator of the G1-phase progression of the cell cycle, has been identified as the long-sought BCL-1 oncogene in B-cell malignancies with t(11;14)(q13;q32) translocation. A novel alternative spliced cyclin-D1 transcript, called transcript[b], has been identified. The level of the variant transcript[b] was lower than that of the originally reported cyclin-D1 transcript, called transcript[a], in several human non-lymphoid cancer cell lines but the endogenous cellular expression of transcript[b] products has not yet been determined. Northern-blot analysis and reverse-transcription-polymerase-chain-reaction (RT-PCR) analysis revealed that transcript[b] mRNA is well expressed in B-lymphoid cell lines with t(11;14)(q13;q32) translocation and at much lower or undetectable levels in other cells. Western-blot analysis using a human cyclin-D1-specific monoclonal antibody, which can recognize and distinguish the products of transcripts [a] and [b], strongly suggested that the transcript [b] protein is indeed expressed in these B-cell lines. The present study provides identification of the endogenous cellular expression of the cyclin-D1-transcript[b] protein and strongly suggests that this alternative form of cyclin D1 may play a significant role in the molecular pathogenesis of B-lymphoid malignancies with t(11;14)(q13;q32) translocation.
Hosokawa
Y
Y
Laboratory of Chemotherapy, Aichi Cancer Center Research Institute, Nagoya, Japan. yhosokaw@aichi-cc.pref.aichi.jp
Joh
T
T
Maeda
Y
Y
Arnold
A
A
Seto
M
M
D017398:Alternative Splicing; D000818:Animals; D001943:Breast Neoplasms; D002051:Burkitt Lymphoma / Q000235:genetics; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11; D002883:Chromosomes, Human, Pair 14; D019938:Cyclin D1 / Q000235:genetics*; D005260:Female; D006801:Humans; D019169:Jurkat Cells; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics*; D016393:Lymphoma, B-Cell / Q000235:genetics*; D051379:Mice; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014178:Translocation, Genetic; D014407:Tumor Cells, Cultured
D019938:Cyclin D1