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

Revised: 23 November 2015, last major update July 2013

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

PubMed Search: CDK4[title]
  • Complex is key regulator of transition through G1 phase of cell cycle (Genes Cancer 2012;3:658)
  • Also called Cyclin-dependent kinase 4
  • Among cyclin/CDKs, CDK4 and cyclin D1 are the most frequently activated by somatic genetic alterations in multiple tumor types (Proc Natl Acad Sci USA 2009;106:4166)
  • Well differentiated and dedifferentiated family of liposarcomas demonstrates amplification of chromosome subregion 12q13-q15 with resultant amplification of MDM2 and CDK4 genes
Diagrams / Tables

CDK4 binds with cyclin D

CDK4 regulation and activation

Clinical Features
Uses by Pathologists
Micro Images

Images hosted on other servers:

Breast carcinoma

Liposarcoma - dedifferentiated (left), well differentiated (right)

Images hosted on

Low grade osteosarcoma

Missing Image


Parosteal osteosarcoma

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Breast carcinoma

Positive Stains
  • Atypical lipomatous tumor / well differentiated liposarcoma (due to amplification of MDM2 and CDK4)
  • Dedifferentiated liposarcoma arising from atypical lipomatous tumor / well differentiated liposarcoma
  • Dedifferentiated liposarcoma with meningothelial-like whorls (Am J Surg Pathol 2011;35:356)
  • Low grade osteosarcomas (Mod Pathol 2011;24:624) and high grade osteosarcomas that progressed from low grade osteosarcomas (Am J Surg Pathol 2012;36:423)
  • Some cases of undifferentiated high grade pleomorphic sarcoma (Am J Surg Pathol 2009;33:1594)
Negative Staining
  • Carcinoma, lymphoma, sarcomas other than atypical lipomatous tumor / well differentiated liposarcoma (or dedifferentiated liposarcoma arising from it)
Molecular / Cytogenetics Images

Glioblastoma multiforme