Apoptosis and Necrosis Flashcards
1
Q
Two types of Neoplasms
A
- BENIGN- slow growth, localized,encapsulated,resembles cell of origin, few mitosis, normal or slight increase in ratio of nucleus to cytoplasm. Cells are uniform throughout the tumor,resembles cells of origin (well differentiated).
- MALIGNANT-rapid growth/proliferation,may spread. Abnormal growth tissue,cancer cell unregulated,cells and nuclei vary in shape and size, high nuclear to cytoplasmic ration, many mitosis, NOT ENCAPSULATED.
2
Q
Carcinoma
A
Malignant tumor growing from Epithelial tissue cancer
-glands
3
Q
Sarcoma
A
Malignant tumor growing from Connective tissue cancer
- bones
- blood
- cartilage
- fat
- muscle
- tendons
4
Q
Metastasis
A
Distant spread of the tumor cells into other tissues of the body. MODES -Vascular-veins -Lymphatic-lymphatic vessels -Transcoelomic-across coelomic spaces Ex. Peritoneal and pleural cavities
5
Q
Tumor formation (two theories)
A
- Clonal evolution-develops through repeated rounds of mutation and proliferation
- cells acquire selective growth advantage over neighbor cells
- Stem cell evolution
- Tumors contain cancer stem cells
- Indefinite proliferative potential
- Linked initially to Leukemia’s
6
Q
Two major mechanisms of Cell death
A
- NECROSIS
- Ischemia
- toxins
- infections
- trauma
- APOPTOSIS
- Regulated cell death
- Occurs throughout adulthood and development
- Physiological (development, tissue homeostasis) and some pathological conditions such as DNA damage, misfolded proteins, some viral infections
7
Q
Necrosis (PACCLCSI)
A
- Pathological
- Acute cell injury
- Cell swelling
- Cell unable to maintain homeostasis
- Loss of tissue membrane integrity ( damage to plasma membrane)-Random DNA degradation
- Cell contents released
- Surrounding tissue damage
- Inflammation
8
Q
APOPTOSIS
A
- Physiological
- Genetic
- Programmed cell death
- Cell shrinking
- Maintains plasma membrane integrity
- PLASMA MEMBRANE BLEBBING
- DNA aggregation-Aggregation of chromatin
- Fragmentation of oligonucleosomal DNA/Nucleus
- Capsase cascade activation
- No surrounding tissue damage
- No inflammation
9
Q
ASSESMENT OF NECROSIS
A
MORPHOLOGICAL
- Propidium Iodide (PI) staining
- PI positive-leaky/discontinuous plasma membrane-necrosis
- H&E staining
- increased eosinophilia
- variable nuclei staining
- TEM
- Discontinuous plasma and organelle membranes
BIOCHEMICAL
-Random DNA degradation- increased levels of LDH-Lactate dehydrogenase
10
Q
CYTOKINES MACROPHAGE RELEASES TO INHIBIT INFLAMMATION
A
** ILB-10
** TGF-BETA
11
Q
CYTOCHROME C
A
Released from the mitochondria for apoptosis
12
Q
WEBBING OF HUMAN TOES
A
Interruption of Apoptosis
13
Q
Mechanisms of Apoptosis
-TWO PATHWAYS
A
- Intrinsic
- Death signal received
- Pro-apoptotic proteins unregulated
- Release of cytochrome c from mitochondria
- Apoptosome formation (Apache-1,cytochrome c, procaspace 9)
- Caspase cascade-activation of initiator Caspace 9 and effector Caspace 3
- Extrinsic
- Binding of ligand to death receptor
- Fas ligand
- Recruitment of death adaptor proteins
- FADD
- TRADD
- Formation of death inducing signaling complex (DISC)
- Capsase cascade:
- Activation of initiator Capsase 8
- Activation of effector or “executioner” caspases ex. Caspase 3
14
Q
CASPACE FAMILY
A
Family of protease enzymes
- Cysteine dependent, aspartame-directed protease
- synthesized as inactive precursors-procaspaces
- activated by proteolytic cleavage
- target cytoplasmic and nuclear proteins and Caspace-active DNAse
15
Q
CASPASE 1
A
Cytokines maturation
