Intrinsic brain tumors have two features that make them different from other types of cancer. One, is they rarely, if ever, metastasize to other organs in the body. Two, cells often break away from the main mass to invade the surrounding brain and form new growths a few millimeters or more away. These tumors are more common in children and the elderly than in the general population. The most malignant of these is called glioblastoma multiforme (GBM).
Intracranial tumors are the most common cause of death by cancer in people under twenty years old. Second only to leukemia, they are the most common cause of cancer death in men aged 20-29. Neural tumors are the 5th leading cause of cancer fatalities in women aged 20-39.
The incidence of GBM is very low, between two and three new cases per 100,000. Because of their ability to migrate away from the parent tumor and start new growths, complete surgical excision is impossible. Try scraping off all of the butter from your next slice of toast.
GBM starts in glial cells within the brain, the so-called "helper" cells. While nerve cells stop dividing once they achieve terminal differentiation, glial cells retain the ability to divide throughout the life of the parent organism, i. E., you and me. In vivo studies in the 1960s and in vitro research from the early 2000s seems to indicate that most, if not all, intrinsic brain tumors originate in the developing fetus.
The human brain is home to three types of glial cells: oligodendrocytes, astrocytes and microglial cells. The most numerous of these are the astrocytes, star-shaped cells. These cells give rise to tumors called astrocytomas, the most malignant of which are the GBM. The median survival time in GBM is less than five months if left untreated.
Astrocytes, situated in the brain and spinal cord, have several important functions. Among these is providing support to the vascular cells that make up the blood brain barrier, providing nutrients to neuronal tissue and repairing damage caused by CNS trauma. Recent experiments indicate that one way that astrocytes communicate with nerve cells is by releasing glutamate, an excitatory neurotransmitter.
Oligodendrocytes are less spiny than their astrocytic cousins. Their main role in the nervous system is to provide a fatty sheath of insulation that makes more rapid nerve transmission possible. One oligodendrocyte can ensheath up to 50 neurons. The fatty sheath, called myelin, comes under attack from immune system cells in the debilitating condition known as multiple sclerosis (MS).
Microglia are a special type of immune system cell resident within the central nervous system. These cells respond quickly to invasion from foreign bodies, embrace them through a process called phagocytosis and present them for destruction by T-cells. Resting microglia look very cute under the microscope, with tiny spines called processes. Activated microglia share more morphological characteristics with cells of the immune system, or leukocytes.
Intracranial tumors are the most common cause of death by cancer in people under twenty years old. Second only to leukemia, they are the most common cause of cancer death in men aged 20-29. Neural tumors are the 5th leading cause of cancer fatalities in women aged 20-39.
The incidence of GBM is very low, between two and three new cases per 100,000. Because of their ability to migrate away from the parent tumor and start new growths, complete surgical excision is impossible. Try scraping off all of the butter from your next slice of toast.
GBM starts in glial cells within the brain, the so-called "helper" cells. While nerve cells stop dividing once they achieve terminal differentiation, glial cells retain the ability to divide throughout the life of the parent organism, i. E., you and me. In vivo studies in the 1960s and in vitro research from the early 2000s seems to indicate that most, if not all, intrinsic brain tumors originate in the developing fetus.
The human brain is home to three types of glial cells: oligodendrocytes, astrocytes and microglial cells. The most numerous of these are the astrocytes, star-shaped cells. These cells give rise to tumors called astrocytomas, the most malignant of which are the GBM. The median survival time in GBM is less than five months if left untreated.
Astrocytes, situated in the brain and spinal cord, have several important functions. Among these is providing support to the vascular cells that make up the blood brain barrier, providing nutrients to neuronal tissue and repairing damage caused by CNS trauma. Recent experiments indicate that one way that astrocytes communicate with nerve cells is by releasing glutamate, an excitatory neurotransmitter.
Oligodendrocytes are less spiny than their astrocytic cousins. Their main role in the nervous system is to provide a fatty sheath of insulation that makes more rapid nerve transmission possible. One oligodendrocyte can ensheath up to 50 neurons. The fatty sheath, called myelin, comes under attack from immune system cells in the debilitating condition known as multiple sclerosis (MS).
Microglia are a special type of immune system cell resident within the central nervous system. These cells respond quickly to invasion from foreign bodies, embrace them through a process called phagocytosis and present them for destruction by T-cells. Resting microglia look very cute under the microscope, with tiny spines called processes. Activated microglia share more morphological characteristics with cells of the immune system, or leukocytes.
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