Mantle Cell Lymphoma : Cyclin D1

Comments:
Most cases of mantle cell lymphoma show t(11;14)(q13;q32) translocation involving the IGH locus on chromosome 14 and CCND1 (cyclin D1) locus on chromosome 11. This leads to overexpression of cyclin D1 which can be detected immunohistochemically in the nuclei of tumor cells. Cyclin D1 overexpression accelerates G1- to S-phase progression in the cell cycle promoting cell proliferation. The translocation can be detected by cytogenetics in about 70% of cases and by FISH in almost 100% of cases.

About 7% of mantle cell lymphomas are negative for cyclin D1 and instead produce cyclin D2 or cyclin D3. Rare cases of variant CCND1 translocation involving immunoglobulin light chains have been reported. The blastoid variant may show TP53 mutations, MYC translocation t(8;14)(q24;q32), and tetraploidy. These are associated with aggressive behavior.

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