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.
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.
GBM is rare, with only two or three new cases per 100,000 population. They account for one-fifth of all tumors inside the cranium. Because of GBM cells' ability to break away from the main tumor, migrate a few millimeters within the brain and start dividing again to form new tumors, they are impossible to completely eradicate by surgery. It's is like trying to remove all the butter from a slice of toast.
The type of cell that gives rise to GBM is the glial cell, of which there are three types. Nerve cells lose their ability to divide once they have reached terminal differentiation. Glial cells, on the other hand, are able to divide throughout the life of the individual. Evidence from both in vivo studies in the '60s and in vitro studies in the '90s and early 21st century support the hypothesis that most, if not all, intrinsic brain tumors begin forming in the developing fetus.
There are three different types of glial cells in the brain, each with different functions. These are astrocytes, microglia and oligodendrocytes. Astrocytes are the most common neural cell type found in brain tumors. These are called astrocytomas. GBM is the most malignant of the astrocytomas, with median survival time of less than five months without treatment.
Astrocytes are star-shaped glial cells found in the brain and spinal cord. The provide support to the endothelial cells that form the blood brain barrier, provide nutrients to nervous tissue and form a part of the repair process following trauma to the central nervous system. There is evidence to suggest that astrocytes communicate with nerve cells by releasing a neurotransmitter called glutamate.
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.
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.
GBM is rare, with only two or three new cases per 100,000 population. They account for one-fifth of all tumors inside the cranium. Because of GBM cells' ability to break away from the main tumor, migrate a few millimeters within the brain and start dividing again to form new tumors, they are impossible to completely eradicate by surgery. It's is like trying to remove all the butter from a slice of toast.
The type of cell that gives rise to GBM is the glial cell, of which there are three types. Nerve cells lose their ability to divide once they have reached terminal differentiation. Glial cells, on the other hand, are able to divide throughout the life of the individual. Evidence from both in vivo studies in the '60s and in vitro studies in the '90s and early 21st century support the hypothesis that most, if not all, intrinsic brain tumors begin forming in the developing fetus.
There are three different types of glial cells in the brain, each with different functions. These are astrocytes, microglia and oligodendrocytes. Astrocytes are the most common neural cell type found in brain tumors. These are called astrocytomas. GBM is the most malignant of the astrocytomas, with median survival time of less than five months without treatment.
Astrocytes are star-shaped glial cells found in the brain and spinal cord. The provide support to the endothelial cells that form the blood brain barrier, provide nutrients to nervous tissue and form a part of the repair process following trauma to the central nervous system. There is evidence to suggest that astrocytes communicate with nerve cells by releasing a neurotransmitter called glutamate.
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.
About the Author:
You can visit www.megapedia.net for more helpful information about The Parent Cells Of Glioblastoma.
0 nhận xét:
Đăng nhận xét