lOMoARcPSD|26582732
IMMUNITY week 5Pharmacology I
(Arizona College of
Nursing)
Types of Cancer
1. Carcinomas:
0 Origin: Glandular epithelial tissue.
○ Common Locations: Skin, mucous membranes lining the mouth, throat, lungs,
and gastrointestinal tract.
○ Example: Ductal Carcinoma – A type of breast cancer that originates in the milk
ducts, the epithelial tissue lining the ducts that carry milk from the lobes of the
breast to the nipple.
○ Manifestation: Often manifests as a mass or lump in the breast, abnormal
discharge from the nipple, or changes in breast shape or skin texture.
2. Sarcomas:
0 Origin: Cartilage, connective tissues, and bones.
○ Common Locations: Muscles, bones, cartilage, and adipose (fat) tissues.
○ Example: Osteosarcoma – A cancer that originates in the bone cells, often
occurring in the long bones, such as the legs or arms.
○ Manifestation: Pain, swelling, and tenderness in the affected bones, fractures
that occur with minimal trauma.
3. Leukemias:
0 Origin: Blood-forming tissue, such as the bone marrow.
○ Common Locations: Blood and bone marrow.
○ Example: Acute Lymphoblastic Leukemia (ALL) – A cancer of the bone
marrow and blood that primarily affects the lymphoid cells, which are a type of
white blood cell.
○ Manifestation: Fatigue, easy bruising or bleeding, recurrent infections, fever,
weight loss, and bone pain.
4. Lymphomas:
0 Origin: Lymphatic tissue.
○ Common Locations: Lymph nodes, spleen, and other lymphatic organs.
○ Example: Hodgkin's Lymphoma – A type of lymphoma that typically starts in
the lymph nodes and spreads to other lymphatic tissues.
○ Manifestation: Swollen lymph nodes, fever, night sweats, weight loss, and
fatigue.
Breast Cancer Example:
● Ductal Carcinoma in Situ (DCIS):
0 A non-invasive cancer confined to the milk ducts. It is considered a precancerous
condition because it hasn’t spread beyond the ducts.
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○ Manifestation: May cause a lump in the breast or abnormal findings on a
mammogram. It is typically asymptomatic in its early stages.
● Lobular Carcinoma:
0 Occurs in the lobules of the breast, the glands that produce milk.
○ Manifestation: It often presents as a thickening in the breast tissue and may be
harder to detect than ductal carcinoma.
Understanding Cancer Terminology:
The use of Greek and Latin roots can help understand the names of various cancers. For
example:
● "Carcinoma" comes from the Greek word "karkinos", meaning "crab," due to the
crablike spread of cancer cells.
● "Sarcoma" comes from the Greek "sarx", meaning "flesh."
● "Leukemia" is derived from the Greek "leukos" (white) and "haima" (blood), referring
to the excess of white blood cells in the blood.
● "Lymphoma" comes from "lympho-", referring to the lymphatic system, and "-oma",
which means tumor.
Phases of the Cell Cycle:
1. G1 Phase (Gap 1):
0 Purpose: The cell prepares for DNA synthesis. It undergoes growth and normal
metabolic activities. During this phase, the cell checks for proper environmental
conditions to ensure it can move into the next phase.
○ Cell Behavior: The cell increases in size, synthesizes proteins, and prepares
the necessary enzymes for DNA replication.
2. S Phase (Synthesis):
0 Purpose: The cell actively replicates its DNA. Each chromosome is duplicated
so that each daughter cell will receive an identical set of chromosomes.
○ Cell Behavior: DNA synthesis occurs, ensuring that the cell's genetic material is
ready for division.
3. G2 Phase (Gap 2):
0 Purpose: The cell prepares for mitosis, completing any final steps before
division. It also checks the replicated DNA for errors to ensure that no genetic
mutations are passed to the daughter cells.
○ Cell Behavior: The cell continues to grow and produce proteins necessary for
mitosis. At the end of G2, the cell undergoes a checkpoint to verify that the DNA
replication is complete and accurate.
4. M Phase (Mitosis):
0 Purpose: This is when cell division occurs, resulting in two genetically identical
daughter cells.
○ Cell Behavior: Mitosis consists of several sub-phases: prophase, metaphase,
anaphase, and telophase, followed by cytokinesis (the division of the cytoplasm),
ensuring that each new cell has the correct amount of DNA.
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Chemotherapy and the Cell Cycle:
Chemotherapy drugs are designed to target and kill cancer cells, which tend to have a high
growth fraction (a large proportion of the cells are dividing rather than resting). Here's how
chemotherapy works in relation to the cell cycle:
● Chemotherapeutic drugs primarily disrupt the cell cycle in the following ways:
1. DNA Synthesis Interference: Many chemotherapy drugs (such as
antimetabolites like methotrexate) interfere with the synthesis of DNA during the
S phase. These drugs mimic normal building blocks of DNA, disrupting the
replication process and leading to cell death.
2. Mitosis Disruption: Other chemotherapy agents (like mitotic inhibitors such as
vincristine or paclitaxel) prevent proper cell division in the M phase. They
interfere with microtubules, structures necessary for the separation of
chromosomes during mitosis, effectively halting the division process.
● Growth Fraction Sensitivity: Cancer cells often have a higher proportion of cells in the
dividing phase of the cycle (high growth fraction). As a result, they are more sensitive to
chemotherapy drugs that target rapidly dividing cells.
● Toxicity to Normal Cells: While chemotherapy is effective at killing cancer cells, it also
affects normal cells, especially those that divide rapidly. This is why chemotherapy
causes side effects such as hair loss, nausea, fatigue, and immune suppression.
Cells in the bone marrow, gastrointestinal tract, and hair follicles have a high turnover
rate and are particularly susceptible to chemotherapy damage.
Summary:
The cell cycle ensures the accurate replication and division of cells, and chemotherapy works by
interfering with either DNA synthesis or mitosis, both of which are essential for cell division.
Because cancer cells divide more rapidly than normal cells, they are particularly vulnerable to
chemotherapy. However, this treatment can also harm healthy cells that are undergoing rapid
division, leading to various side effects. Understanding the cell cycle is crucial to developing
targeted therapies and improving the effectiveness and safety of cancer treatments.
Human Immunodeficiency Virus (HIV) is a virus that attacks the body's immune system,
specifically targeting CD4-T cell lymphocytes. These cells are crucial for coordinating the
immune response, as they help activate B lymphocytes (which produce antibodies) and
Tlymphocytes or macrophages (which destroy infected cells). When HIV infects these cells, it
weakens the immune system, making the body more susceptible to infections and diseases.
Key Characteristics of HIV:
1. Retrovirus:
0 HIV is classified as a retrovirus because its genetic material is in the form of
RNA rather than the typical DNA found in many other organisms.
○ The retrovirus uses a process called reverse transcription to convert its RNA
into DNA after entering a host cell, allowing it to integrate into the host's genome
and replicate.
2. HIV-1 vs. HIV-2:
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IMMUNITY week 5Pharmacology I
(Arizona College of
Nursing)
Types of Cancer
1. Carcinomas:
0 Origin: Glandular epithelial tissue.
○ Common Locations: Skin, mucous membranes lining the mouth, throat, lungs,
and gastrointestinal tract.
○ Example: Ductal Carcinoma – A type of breast cancer that originates in the milk
ducts, the epithelial tissue lining the ducts that carry milk from the lobes of the
breast to the nipple.
○ Manifestation: Often manifests as a mass or lump in the breast, abnormal
discharge from the nipple, or changes in breast shape or skin texture.
2. Sarcomas:
0 Origin: Cartilage, connective tissues, and bones.
○ Common Locations: Muscles, bones, cartilage, and adipose (fat) tissues.
○ Example: Osteosarcoma – A cancer that originates in the bone cells, often
occurring in the long bones, such as the legs or arms.
○ Manifestation: Pain, swelling, and tenderness in the affected bones, fractures
that occur with minimal trauma.
3. Leukemias:
0 Origin: Blood-forming tissue, such as the bone marrow.
○ Common Locations: Blood and bone marrow.
○ Example: Acute Lymphoblastic Leukemia (ALL) – A cancer of the bone
marrow and blood that primarily affects the lymphoid cells, which are a type of
white blood cell.
○ Manifestation: Fatigue, easy bruising or bleeding, recurrent infections, fever,
weight loss, and bone pain.
4. Lymphomas:
0 Origin: Lymphatic tissue.
○ Common Locations: Lymph nodes, spleen, and other lymphatic organs.
○ Example: Hodgkin's Lymphoma – A type of lymphoma that typically starts in
the lymph nodes and spreads to other lymphatic tissues.
○ Manifestation: Swollen lymph nodes, fever, night sweats, weight loss, and
fatigue.
Breast Cancer Example:
● Ductal Carcinoma in Situ (DCIS):
0 A non-invasive cancer confined to the milk ducts. It is considered a precancerous
condition because it hasn’t spread beyond the ducts.
Downloaded by NELSON KIIRU ()
, lOMoARcPSD|26582732
○ Manifestation: May cause a lump in the breast or abnormal findings on a
mammogram. It is typically asymptomatic in its early stages.
● Lobular Carcinoma:
0 Occurs in the lobules of the breast, the glands that produce milk.
○ Manifestation: It often presents as a thickening in the breast tissue and may be
harder to detect than ductal carcinoma.
Understanding Cancer Terminology:
The use of Greek and Latin roots can help understand the names of various cancers. For
example:
● "Carcinoma" comes from the Greek word "karkinos", meaning "crab," due to the
crablike spread of cancer cells.
● "Sarcoma" comes from the Greek "sarx", meaning "flesh."
● "Leukemia" is derived from the Greek "leukos" (white) and "haima" (blood), referring
to the excess of white blood cells in the blood.
● "Lymphoma" comes from "lympho-", referring to the lymphatic system, and "-oma",
which means tumor.
Phases of the Cell Cycle:
1. G1 Phase (Gap 1):
0 Purpose: The cell prepares for DNA synthesis. It undergoes growth and normal
metabolic activities. During this phase, the cell checks for proper environmental
conditions to ensure it can move into the next phase.
○ Cell Behavior: The cell increases in size, synthesizes proteins, and prepares
the necessary enzymes for DNA replication.
2. S Phase (Synthesis):
0 Purpose: The cell actively replicates its DNA. Each chromosome is duplicated
so that each daughter cell will receive an identical set of chromosomes.
○ Cell Behavior: DNA synthesis occurs, ensuring that the cell's genetic material is
ready for division.
3. G2 Phase (Gap 2):
0 Purpose: The cell prepares for mitosis, completing any final steps before
division. It also checks the replicated DNA for errors to ensure that no genetic
mutations are passed to the daughter cells.
○ Cell Behavior: The cell continues to grow and produce proteins necessary for
mitosis. At the end of G2, the cell undergoes a checkpoint to verify that the DNA
replication is complete and accurate.
4. M Phase (Mitosis):
0 Purpose: This is when cell division occurs, resulting in two genetically identical
daughter cells.
○ Cell Behavior: Mitosis consists of several sub-phases: prophase, metaphase,
anaphase, and telophase, followed by cytokinesis (the division of the cytoplasm),
ensuring that each new cell has the correct amount of DNA.
Downloaded by NELSON KIIRU ()
, lOMoARcPSD|26582732
Chemotherapy and the Cell Cycle:
Chemotherapy drugs are designed to target and kill cancer cells, which tend to have a high
growth fraction (a large proportion of the cells are dividing rather than resting). Here's how
chemotherapy works in relation to the cell cycle:
● Chemotherapeutic drugs primarily disrupt the cell cycle in the following ways:
1. DNA Synthesis Interference: Many chemotherapy drugs (such as
antimetabolites like methotrexate) interfere with the synthesis of DNA during the
S phase. These drugs mimic normal building blocks of DNA, disrupting the
replication process and leading to cell death.
2. Mitosis Disruption: Other chemotherapy agents (like mitotic inhibitors such as
vincristine or paclitaxel) prevent proper cell division in the M phase. They
interfere with microtubules, structures necessary for the separation of
chromosomes during mitosis, effectively halting the division process.
● Growth Fraction Sensitivity: Cancer cells often have a higher proportion of cells in the
dividing phase of the cycle (high growth fraction). As a result, they are more sensitive to
chemotherapy drugs that target rapidly dividing cells.
● Toxicity to Normal Cells: While chemotherapy is effective at killing cancer cells, it also
affects normal cells, especially those that divide rapidly. This is why chemotherapy
causes side effects such as hair loss, nausea, fatigue, and immune suppression.
Cells in the bone marrow, gastrointestinal tract, and hair follicles have a high turnover
rate and are particularly susceptible to chemotherapy damage.
Summary:
The cell cycle ensures the accurate replication and division of cells, and chemotherapy works by
interfering with either DNA synthesis or mitosis, both of which are essential for cell division.
Because cancer cells divide more rapidly than normal cells, they are particularly vulnerable to
chemotherapy. However, this treatment can also harm healthy cells that are undergoing rapid
division, leading to various side effects. Understanding the cell cycle is crucial to developing
targeted therapies and improving the effectiveness and safety of cancer treatments.
Human Immunodeficiency Virus (HIV) is a virus that attacks the body's immune system,
specifically targeting CD4-T cell lymphocytes. These cells are crucial for coordinating the
immune response, as they help activate B lymphocytes (which produce antibodies) and
Tlymphocytes or macrophages (which destroy infected cells). When HIV infects these cells, it
weakens the immune system, making the body more susceptible to infections and diseases.
Key Characteristics of HIV:
1. Retrovirus:
0 HIV is classified as a retrovirus because its genetic material is in the form of
RNA rather than the typical DNA found in many other organisms.
○ The retrovirus uses a process called reverse transcription to convert its RNA
into DNA after entering a host cell, allowing it to integrate into the host's genome
and replicate.
2. HIV-1 vs. HIV-2:
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