1
,ribonucleic acids (miRNAs &miRs). Human development depends on epigenetics because in
early embryonic development, the cells of the embryo have the potential to become any cell in
the future. These stem cells are said to be pluripotent (capable of giving rise to several different
cell types). Specific DNA nucleotide sequences get modified. Non-genetic or environmental
factors like diet and exposure can lead epigenetics.
Totipotent cells and its ability to differentiate into any type of cell- The embryonic cells that
develop from totipotent stem cells and are precursors to the fundamental tissue layers of the
embryo are classified as pluripotent. A pluripotent stem cell is one that has the potential to
differentiate into any type of human tissue but cannot support the full development of an
organism. Totipotent stem cells are perhaps the most versatile of the stem cell types. As
explained, a totipotent zygote cell is created when a single celled sperm and egg unite. This
totipotent fertilized egg has the potential to give rise to virtually all human cells, such as nerve or
heart. It is during the early cell divisions in embryonic development that more totipotent cells are
produced. Within several days, these totipotent cells divide and create replicas, therefore
producing more totipotent cells. It is after approximately four days that the cells begin to
specialize into pluripotent cells, which can go on to specialize further but can't ever produce an
entire organism as totipotent cells can. Basically, the pluripotent stem cell can do everything the
totipotent one can except for creating an entire organism.They have the ability to become any
cell type in a fully developed human. They have the ability to replicate in unlimited numbers
without losing their total potency. totipotent cells can develop into any cell type, which makes
them ideal for cell and gene therapies as well as tissue engineering for transplants and
replacement of diseased cells. This means that the therapeutic value of totipotent stem cells is
,enormous. By learning about the process of division, we can find out what goes wrong in disease
states and then investigate ways to prevent diseased cell production and division.
Prader-Willi syndrome and Angelman syndromePg 187- Prader-Willi: When deletion is inherited
from the father, imprinting with the affect of a deletion of about 4 million base pairs (Mb) of the
long arm of chromosome 15. Children will exhibit short stature, hypotonia, small hands and feet,
obesity, mild to moderate mental retardation and hypogonadism. Angelman syndrome: When the
same 4 Mb deletion is seen and inherited by the mother- Characterized by severe mental
retardation, seizures, and an ataxic gait. These diseased are seen in about 1 in 15000 live births.
The deletions are the cause of about 70% of the cases of both diseases. This is A CRITICAL
AREA that got deleted.
Cellular Proliferation
5-Azacytidine and the treatment of cancer:5-Azacytidine is a cytosine analog and a potent DNA
methyltransferase inhibitor, previously shown to induce DNA demethylation. Treatment with 5-
Azacytidine is used for patients with higher-risk myelodysplastic syndrome (MDS), and for a
subgroup of acute myeloid leukemia (AML) and chronic myelomonocytic leukemia
(CMML) patients. 5- Azactytide has demonstrated promise in the treatment of pancreatic cancer.
The role of inactive MLH1 in the development of some forms of inherited colon cancer:PG186
DNA damage is unrepaired, A major cause of one form of inherited colon cancer (hereditary
nonpolyposis colorectal cancer [HNPCC]) is the methylation of the promoter region of a gene,
MLH1, whose protein product repairs damaged DNA. When MLH1 becomes inactive, DNA
damage accumulates, eventually resulting in colon tumors. Facioscapulohumeral muscular
dystrophy (FSHMD) is associated with the DUX4 gene. Fragile X is associated with the
, cytosine-guanine (CG) dinucleotide. Down regulation of IGF2 is associated with Russell-Silver
syndrome.
Effects of ethanol on neural stem cells ability to differentiate into functional neurons: pg 185
Recent findings indicate that NSCs (specifically, in the dentate gyrus of the hippocampus and in
the SVC of the anterior lateral ventricles) divide throughout life and give rise to new neurons.
The factors that regulate neurogenesis overlap with those that are altered as alcohol use becomes
alcoholism (e.g., stress, activity, learning, and other unknown environmental and genetic
factors). Although the mechanisms involved are not well understood, it is possible that
modulation of neurogenesis contributes significantly to alcoholic pathology. In animal models,
high doses of alcohol have been shown to disrupt neurogenesis, and may underlie long–term
deficits in hippocampal structure and function. More moderate but chronic alcohol consumption
also affects neurogenesis, suggesting that inhibition of neurogenesis may contribute to the
neurodegeneration associated with chronic alcoholism. Kills and decreases the amount of NSC.
Inflammation as an etiology for cancer-note conditions in which this may occur: infiltrating
immune cells can cause chronic inflammation and therefore create a permissive tumor-
progressing environment. It can precede and initiate malignant changes. PG. 403, 383
Cancer Chapter 12 & 13
In terms of epigenetic modifications, the role of environmental stressors associated with
development of cancer: Pg 403, 413& 472 Environmental stressors hit an Epigenetic mutation
multiple times, it is show that when enough ‗hits‘ happen, cancers develop. Due to
environmental stressors. The malfunction of DNA methylation can lead to cancer. Cancer
progression is due to environmental factors such as tobacco smoke, asbestos, and fine particles in
,ribonucleic acids (miRNAs &miRs). Human development depends on epigenetics because in
early embryonic development, the cells of the embryo have the potential to become any cell in
the future. These stem cells are said to be pluripotent (capable of giving rise to several different
cell types). Specific DNA nucleotide sequences get modified. Non-genetic or environmental
factors like diet and exposure can lead epigenetics.
Totipotent cells and its ability to differentiate into any type of cell- The embryonic cells that
develop from totipotent stem cells and are precursors to the fundamental tissue layers of the
embryo are classified as pluripotent. A pluripotent stem cell is one that has the potential to
differentiate into any type of human tissue but cannot support the full development of an
organism. Totipotent stem cells are perhaps the most versatile of the stem cell types. As
explained, a totipotent zygote cell is created when a single celled sperm and egg unite. This
totipotent fertilized egg has the potential to give rise to virtually all human cells, such as nerve or
heart. It is during the early cell divisions in embryonic development that more totipotent cells are
produced. Within several days, these totipotent cells divide and create replicas, therefore
producing more totipotent cells. It is after approximately four days that the cells begin to
specialize into pluripotent cells, which can go on to specialize further but can't ever produce an
entire organism as totipotent cells can. Basically, the pluripotent stem cell can do everything the
totipotent one can except for creating an entire organism.They have the ability to become any
cell type in a fully developed human. They have the ability to replicate in unlimited numbers
without losing their total potency. totipotent cells can develop into any cell type, which makes
them ideal for cell and gene therapies as well as tissue engineering for transplants and
replacement of diseased cells. This means that the therapeutic value of totipotent stem cells is
,enormous. By learning about the process of division, we can find out what goes wrong in disease
states and then investigate ways to prevent diseased cell production and division.
Prader-Willi syndrome and Angelman syndromePg 187- Prader-Willi: When deletion is inherited
from the father, imprinting with the affect of a deletion of about 4 million base pairs (Mb) of the
long arm of chromosome 15. Children will exhibit short stature, hypotonia, small hands and feet,
obesity, mild to moderate mental retardation and hypogonadism. Angelman syndrome: When the
same 4 Mb deletion is seen and inherited by the mother- Characterized by severe mental
retardation, seizures, and an ataxic gait. These diseased are seen in about 1 in 15000 live births.
The deletions are the cause of about 70% of the cases of both diseases. This is A CRITICAL
AREA that got deleted.
Cellular Proliferation
5-Azacytidine and the treatment of cancer:5-Azacytidine is a cytosine analog and a potent DNA
methyltransferase inhibitor, previously shown to induce DNA demethylation. Treatment with 5-
Azacytidine is used for patients with higher-risk myelodysplastic syndrome (MDS), and for a
subgroup of acute myeloid leukemia (AML) and chronic myelomonocytic leukemia
(CMML) patients. 5- Azactytide has demonstrated promise in the treatment of pancreatic cancer.
The role of inactive MLH1 in the development of some forms of inherited colon cancer:PG186
DNA damage is unrepaired, A major cause of one form of inherited colon cancer (hereditary
nonpolyposis colorectal cancer [HNPCC]) is the methylation of the promoter region of a gene,
MLH1, whose protein product repairs damaged DNA. When MLH1 becomes inactive, DNA
damage accumulates, eventually resulting in colon tumors. Facioscapulohumeral muscular
dystrophy (FSHMD) is associated with the DUX4 gene. Fragile X is associated with the
, cytosine-guanine (CG) dinucleotide. Down regulation of IGF2 is associated with Russell-Silver
syndrome.
Effects of ethanol on neural stem cells ability to differentiate into functional neurons: pg 185
Recent findings indicate that NSCs (specifically, in the dentate gyrus of the hippocampus and in
the SVC of the anterior lateral ventricles) divide throughout life and give rise to new neurons.
The factors that regulate neurogenesis overlap with those that are altered as alcohol use becomes
alcoholism (e.g., stress, activity, learning, and other unknown environmental and genetic
factors). Although the mechanisms involved are not well understood, it is possible that
modulation of neurogenesis contributes significantly to alcoholic pathology. In animal models,
high doses of alcohol have been shown to disrupt neurogenesis, and may underlie long–term
deficits in hippocampal structure and function. More moderate but chronic alcohol consumption
also affects neurogenesis, suggesting that inhibition of neurogenesis may contribute to the
neurodegeneration associated with chronic alcoholism. Kills and decreases the amount of NSC.
Inflammation as an etiology for cancer-note conditions in which this may occur: infiltrating
immune cells can cause chronic inflammation and therefore create a permissive tumor-
progressing environment. It can precede and initiate malignant changes. PG. 403, 383
Cancer Chapter 12 & 13
In terms of epigenetic modifications, the role of environmental stressors associated with
development of cancer: Pg 403, 413& 472 Environmental stressors hit an Epigenetic mutation
multiple times, it is show that when enough ‗hits‘ happen, cancers develop. Due to
environmental stressors. The malfunction of DNA methylation can lead to cancer. Cancer
progression is due to environmental factors such as tobacco smoke, asbestos, and fine particles in
