Primary brain tumors, those that originate in the brain, are more frequent in children and older adults. One feature that sets brain tumors apart from those arising from other tissues in the body is their inability to exit the brain to form secondary, or metastatic, tumors in other organs. They do, however, have a tendency to invade the surrounding brain to establish new tumors within the cranium. The most serious type of intrinsic brain tumor is called glioblastoma multiforme, or GBM.
In men and women less than 20 years old, brain cancer is, after leukemia, the next most prevalent cause of cancer deaths. Apart from leukemia, intracranial-derived tumors are the next leading cause of fatality in men between the ages of 20 and 30. In females between 20 and 39 years old, brain tumors are the fifth most prevalent cause of cancer deaths.
Luckily, GBM is infrequent; there are no more than two or three new cases per 100,000 individuals and account for only 20% of all intracranial neoplasms. Their propensity to invade the surrounding brain tissue means that it is not possible for them to be completely eradicated by surgical means. Try scraping off every bit of butter from a 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.
Glial cells come in three different forms: microglia, astrocytes and oligodendrocytes. Of these, astrocytes and astrocytic tumors, are the most common. The nastiest, most malignant and most deadly variant of astrocytoma is the GBM, which has a median time of survival without treatment of less than five months.
Astrocytes are characterized by their starry morphology and the presence of glial fibrillary acidic protein (GFAP). The normal function of astrocytes is to supply nutrients to nerve cells, support the vascular cells that comprise the blood brain barrier and repair damaged cells following trauma. New studies suggest that they communicate with neuronal cells by secreting glutamate, the brain's main 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 the macrophages of the central nervous system. These cells act quickly recognize and destroy foreign bodies, engulf them and present them to other cells of the immune system, called T-cells, before they get the chance to interfere with healthy brain tissue. Microglia exist in two different forms. Resting cells, which resemble tiny astrocytes, and activated microglia, which are more bloated in appearance.
In men and women less than 20 years old, brain cancer is, after leukemia, the next most prevalent cause of cancer deaths. Apart from leukemia, intracranial-derived tumors are the next leading cause of fatality in men between the ages of 20 and 30. In females between 20 and 39 years old, brain tumors are the fifth most prevalent cause of cancer deaths.
Luckily, GBM is infrequent; there are no more than two or three new cases per 100,000 individuals and account for only 20% of all intracranial neoplasms. Their propensity to invade the surrounding brain tissue means that it is not possible for them to be completely eradicated by surgical means. Try scraping off every bit of butter from a 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.
Glial cells come in three different forms: microglia, astrocytes and oligodendrocytes. Of these, astrocytes and astrocytic tumors, are the most common. The nastiest, most malignant and most deadly variant of astrocytoma is the GBM, which has a median time of survival without treatment of less than five months.
Astrocytes are characterized by their starry morphology and the presence of glial fibrillary acidic protein (GFAP). The normal function of astrocytes is to supply nutrients to nerve cells, support the vascular cells that comprise the blood brain barrier and repair damaged cells following trauma. New studies suggest that they communicate with neuronal cells by secreting glutamate, the brain's main 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 the macrophages of the central nervous system. These cells act quickly recognize and destroy foreign bodies, engulf them and present them to other cells of the immune system, called T-cells, before they get the chance to interfere with healthy brain tissue. Microglia exist in two different forms. Resting cells, which resemble tiny astrocytes, and activated microglia, which are more bloated in appearance.
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