Cyclin D1 / bcl1

Author: Nat Pernick, M.D. (see Authors page)

Revised: 30 October 2015, last major update March 2013

Copyright: (c) 2003-2015,, Inc.

PubMed Search: Cyclin+D1[title]
Cite this page: Cyclin D1 . website. Accessed May 23rd, 2017.
Definition / general
  • Also called bcl1 - "b cell lymphoma #1"
  • Coded by BCL1 / PRAD1 (parathyroid adenoma 1) gene on #11q13
  • Responsible for transition to S phase by phosphorylating the retinoblastoma gene product, which releases transcription factors to initiate DNA replication
  • Overexpression promotes transformation to a malignant phenotype; overexpressed in many tumors
  • Cyclin D1 genotypes may be associated with nasopharyngeal carcinoma risk (Anticancer Res 2012;32:1093)
Uses by pathologists
  • Interpretation: nuclear stain
  • Mantle cell lymphoma: characterized by t(11;14) translocation, which places the cyclin D1 gene next to an immunoglobulin heavy chain enhancer gene; among lymphomas, cyclin D1 expression is very specific for mantle cell lymphoma; however, blastoid cases may be negative (Am J Surg Pathol 2012;36:214)
  • Parathyroid: overexpressed in 40% of parathyroid adenomas, strong staining in carcinomas
Microscopic (histologic) images

Images hosted on Pathout server:

Breast: MALT lymphoma is cyclin D1 negative

Images hosted on other servers:

Breast: papilloma and papillary carcinoma

Cervix: various benign and malignant lesions

Mantle cell lympoma (small bowel)

Mantle cell lympoma (axillary lymph node)

Skin: normal

Skin: compound Spitz nevus and melanoma

Stomach: gastric or gastroesophageal junction adenocarcinoma

Uterus: normal, complex hyperplasia and carcinoma

Various images

Virtual slides

Breast: papilloma and papillary carcinoma

Molecular / cytogenetics images

Images hosted on

FISH in mantle cell lymphoma - blastoid variant

FISH in mantle cell lymphoma: cyclin D1/IgH single and double-fusion-positive cells in peripheral
blood sample showing mantle cell lymphoma involvement

Positive staining - normal
Positive staining - disease