Cell cycle signaling antibodies are involved in the cell division cycle of different types of cells. This cell division occurs primarily in the nucleus where the DNA is housed. These processes include replication of DNA and mitosis or cell division. The replication of DNA has 3 distinct phases in which cells will increase in size, DNA is duplicated, and a cell will continue to grow larger until it ultimately divides into two. These 3 phases are followed by the process of mitosis and an effective break or period of rest from division. The many processes that control the cell cycle are highly regulated and complex. Cell cycle signaling involves many different pathways that control everything from apoptosis, growth, gene regulation, immune signaling, neurotransmission, and basic cell cycle processes. Cells must have the ability to perceive these cell cycle signals and correctly respond in order to maintain proper functioning.

Cyclin dependent kinase, or Cdk adds a phosphate to a protein which ultimately switches a cell to start synthesizing DNA (S- phase) and to begin cell division (mitosis). The anti-CDK1 antibody plays a key role in this process. The 2nd isoform of this antibody is found in breast cancer tissues. The anti-alkaline phosphatase antibody (ALP) binds to ALP which removes the phosphate groups from the ends of both DNA and RNA prior to replication. In serum, ALP measurements can be abnormally high when the affected individual suffers from bone disease or liver disease since damaged tissues can release these enzymes into the blood.