pRB, or the retinoblastoma protein, is a crucial tumor suppressor protein in the human body. It was the first protein to be identified with this function, meaning it helps prevent the uncontrolled growth of cells that can lead to cancer.
Key Aspects of pRB
Here's a breakdown of pRB:
- Function: pRB's primary role is to regulate the cell cycle, preventing cells from dividing uncontrollably. It acts as a brake, ensuring that cells only replicate when necessary.
- Discovery: It was initially discovered due to its connection to retinoblastoma, a rare childhood eye cancer. The RB1 gene, responsible for producing pRB, was traced to chromosome 13.
- Role in Retinoblastoma: In 98% of retinoblastoma cases, the function of pRB is lost, allowing cancer cells to proliferate without the normal regulatory controls. This loss of function is usually due to mutations or other issues with the RB1 gene.
- Tumor Suppression: By controlling cell division, pRB prevents the formation of tumors. Its inactivation is linked to the development of many different types of cancer.
- Reference: The retinoblastoma protein (pRB) was the first protein identified as a tumor suppressor. pRB function is lost in 98% of the rare childhood malignancy retinoblastoma, in which the RB1 gene was traced to a locus on chromosome 13 and subsequently sequenced (1–4).
Why pRB is Important
- Cancer Prevention: pRB helps to maintain normal cell growth, preventing the development of tumors.
- Cell Cycle Regulation: pRB is essential for the cell cycle control, ensuring cells do not multiply excessively.
- Therapeutic Target: Understanding pRB's function is essential for developing targeted therapies to restore tumor-suppressive control.
Summary Table
| Protein | Function | Relation to Cancer | Associated Gene |
|---|---|---|---|
| Retinoblastoma Protein (pRB) | Tumor suppressor; regulates cell cycle | Loss of function in 98% of retinoblastoma cases & other cancers | RB1 gene |
In summary, pRB is a vital tumor suppressor protein that regulates cell growth and division. Its loss of function is frequently seen in retinoblastoma and other cancers.
