CDKN1B gene
The CDKN1B gene produces the p27 protein, a tumor suppressor that regulates the cell cycle and prevents uncontrolled cell division.
Normal Function
The CDKN1B gene provides instructions for making a protein called p27. Located primarily in the cell nucleus, p27 acts as a tumor suppressor by blocking cells from entering the phase of the cell cycle where DNA is replicated. By regulating this cycle, p27 prevents cells from dividing too quickly or at the wrong time. It is also involved in cell differentiation. The activity of p27 is tightly regulated; if it is sequestered in the cytoplasm instead of the nucleus, it cannot perform its function of blocking cell cycle progression.
Health Conditions Related to Genetic Changes
Multiple endocrine neoplasia
Mutations in the CDKN1B gene cause a rare form of multiple endocrine neoplasia called type 4. This condition involves the development of tumors in hormone-producing glands, most commonly the parathyroid and pituitary glands. These mutations reduce the amount of functional p27 available in the nucleus, allowing cells to divide in an uncontrolled way and form tumors.
Other tumors
Somatic mutations (not inherited) in the CDKN1B gene have been identified in sporadic pituitary adenomas and sporadic parathyroid adenomas. Additionally, while the gene is rarely mutated in other cancers, a reduction in the amount or function of the p27 protein is often associated with more aggressive tumors and a poorer prognosis in many types of cancer.
Other Names for This Gene
- CDKN4
- CDN1B_HUMAN
- cyclin-dependent kinase inhibitor 1B
- cyclin-dependent kinase inhibitor 1B (p27, Kip1)
- KIP1
- MEN1B
- MEN4
- P27KIP1