KRAS

KRAS Gene

The KRAS gene is a critical component of cellular signaling pathways, specifically the RAS/MAPK pathway. It encodes the K-Ras protein, a GTPase involved in transmitting signals that affect the cell's growth, division, and differentiation. The KRAS gene's function is instrumental in normal cell physiology, but mutations in this gene can lead to uncontrolled cell growth and cancer.

Overview

KRAS (Kirsten rat sarcoma viral oncogene homolog) is one of the human genes encoding a protein called K-Ras, an essential player in the RAS/MAPK pathway. This pathway is crucial for controlling the cell cycle, apoptosis (cell death), cell growth, and differentiation. The K-Ras protein acts as a molecular switch, cycling between an active (GTP-bound) and inactive (GDP-bound) state to relay signals from the cell membrane to the nucleus.

Error creating thumbnail:

Illustration of KRAS signaling in the cell.

Function

The KRAS gene provides instructions for making the K-Ras protein, which is a GTPase. This means it has the ability to hydrolyze GTP into GDP, thereby acting as a molecular switch within the cell. When bound to GTP, K-Ras is in its active form, relaying growth signals to the cell's nucleus. Conversely, when it hydrolyzes GTP to GDP, it becomes inactive, stopping the signal relay.

Significance in Cancer

Mutations in the KRAS gene are among the most common genetic changes observed in human cancers. These mutations often result in the K-Ras protein being permanently activated (always bound to GTP), leading to continuous cell growth and division signals irrespective of external cues. Such constitutive activation is a hallmark of many cancers, including pancreatic, colorectal, and lung cancers.

Current Research

Given its pivotal role in cancer, the KRAS gene and its protein product have been the focus of extensive research aimed at understanding and targeting KRAS-driven tumorigenesis. Efforts include developing inhibitors that specifically target mutant forms of the K-Ras protein and strategies to modulate the downstream effects of KRAS activation.

Therapeutic Approaches

The challenge in targeting KRAS mutations in cancer therapy has been the difficulty in directly inhibiting the mutated K-Ras protein. However, recent advances have led to the development of promising compounds that can specifically inhibit KRAS G12C, a common mutation in lung cancer. These developments mark a significant breakthrough in the potential treatment of KRAS-mutant cancers.

External Links

• National Cancer Institute - KRAS Fact Sheet
• National Human Genome Research Institute - KRAS

References

• Targeting KRAS for Diagnosis, Prognosis, and Treatment of Pancreatic Cancer: Hopes and Realities by European Molecular Biology Organization (EMBO).
• KRAS Mutations and their Role in Cancer Drug Resistance by The Journal of Molecular Diagnostics.

KRAS Resources
Latest articles Most recent articles Ongoing trials	Wikipedia