Cyclin D3

Cyclin D3, also known as CCND3, is a human gene. The protein encoded by this gene belongs to the highlyconserved cyclin family, whose members are characterized by a dramatic periodicity in protein abundance through the cell cycle. Cyclins function as regulators of Cdk kinases. This cyclin forms a complex with and functions as a regulatory subunit of Cdk4 or Cdk6, whose activity is required for cell-cycle G1/S transition. This protein has been shown to interact with and be involved in the phosphorylation of tumor suppressor protein Rb. The Cdk4 activity associated with this cyclin was reported to be necessary for cell-cycle progression through G2 phase into mitosis after UV radiation.

In normal adult tissues, Cyclin D3 shows two patterns of distribution: in lymphoid tissues it is expressed in proliferative compartments, while in most other tissues it is expressed by terminally differentiated/quiescent cells. In non-Hodgkin’s Lymphomas, Cyclin D3 immunolabelling correlates with proliferative activity and progression. Benign endocrine tumors are frequently strongly Cyclin D3-positive, while high-grade (Smallcell) Neuroendocrine Carcinomas are always negative. In Breast Carcinomas, no relationship has been seen between ER status and Ki67 labelling. In soft tissue neoplasms, Cyclin D3 is consistently expressed in some tumors, such as Stromal Tumors of the Gastrointestinal Tract and Embryonal Rhabdomyosarcomas.

Cyclin D3 is a mouse monoclonal antibody derived from cell culture supernatant that is concentrated, dialyzed, filter sterilized and diluted in buffer pH 7.5, containing BSA and sodium azide as a preservative.

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2. Dowdy SF, et al. Cell. 1993;73(3):499-511
3. Lin J, et al. Oncogene. 2001;20(16):2000-2009

1. Cut and mount 3-4 micron formalin-fixed paraffin-embedded tissues on positive charged slides.
2. Air dry for 2 hours at 58° C.
3. Deparaffinize, dehydrate and rehydrate tissues.
4. Subject tissues to heat epitope retrieval using a suitable retrieval solution such as ImmunoDNA Retriever with Citrate (BSB 0020-BSB 0023) or EDTA (BSB 0030-BSB 0033).
5. Any of three heating methods may be used:
   • Electric Pressure Cooker
     Place standoff rack at base of pressure cooker. Add 1-2 inches of distilled water to the pressure cooker and turn heat to high, and incubate for 15 minutes. Open and immediately transfer slides to room temperature.
   • Water Bath Method
     Place tissues/slides in a pre-warmed staining dish or coplin jar containing the ImmunoDNA Retriever with Citrate or EDTA in a water bath set at 95°-99° C. Incubate for 30-60 minutes.
   • Conventional Steamer Method
     Place tissues/slides in a pre-warmed staining dish or coplin jar containing the ImmunoDNA Retriever with Citrate or EDTA in a Steamer, cover and steam for 30-60 minutes.
6. After heat treatment, transfer slides in ImmunoDNA Retriever with Citrate or EDTA to room temperature and let stand for 15-20 minutes.
7. Wash slides with IHC wash buffer or DI water.
8. Continue IHC staining protocol.