Astrocytes

What it is

Astrocytes are star-shaped glial cells that perform many supportive functions in the brain — nourishing neurons, maintaining the chemical environment, and helping form the blood-brain barrier. Astrocytomas, a major category of glioma, are named for their resemblance to these cells.

Understanding Astrocytes

Astrocytes are among the most abundant cells in the brain and are essential for normal function: they support neurons, regulate the balance of chemicals and fluid, contribute to the blood-brain barrier, and respond to injury. When astrocytes or their precursor cells become abnormal and form a tumor, the result is an astrocytoma. The tumor cells often retain features resembling astrocytes, which is how pathologists recognize them. Understanding what astrocytes normally do clarifies the origin of astrocytomas and why these tumors are so named. The behavior of an astrocytoma, however, depends not on the normal role of astrocytes but on the tumor's specific type, grade, and molecular features. Understanding astrocytes provides the cellular basis for astrocytomas.

Why it matters

Understanding astrocytes helps patients and families see the normal brain cells that astrocytomas resemble — clarifying the origin and naming of this major glioma category.