- Cell Cycle
NUR 339 Exam 20
G0 resting phase (becomes mitotically dormant)
- Cell Cycle
G1 (Gap 1) cell prepares to make DNA
- Cell Cycle
S Phase DNA synthesis actually takes place (most mutations occur during this phase)
- Cell Cycle
G2 phase prepares for mitosis (cell division)
- Cell Cycle
M phase mitosis
- benign neoplasm
Composed of well-differentiated cells that resemble cells of tissues of origin
Slow growth rate Remain localized to site of origin without capacity to infiltrate, invade, or metastasize May become encapsulated Less blood supply than malignant neoplasm Usually do not cause death unless interfere with vital functions because of their location Can cause alterations in body function thru abnormal alteration of hormones
- Malignant Neoplasms
Atypical cell structure; abnormal nucleus & chromo- somes 1 / 3
Lose differentiation or resemblance to origin cell--more anaplastic (lack cell differ- entiation)
Not cohesive, irregular growth pattern, no capsule formed, not distinct from sur- rounding tissue Invade adjacent cells rather than pushing aside
Varying growth rates and do not die within normal timeframe More blood supply than normal tissue (angiogenesis)
Hallmark Sign of malignancy
ability to metastasize or spread to distant sites
- metastasis
Ability of CA cells to spread to distant sites
Clumps of malignant cells break off & travel thru blood (hematogenic spread) or lymph (lymphatic spread) to new site - most are killed by body's defense mecha- nisms In lymph nodes, CA may die, grow into mass, or remain dormant
- Sentinel Node
initial lymph node to which primary tumor drains (used to deter- mine spread to lymph system)
- Primary neoplasm
original tumor
- Metastatic Site
secondary neoplasm (retains characteristics of primary tumor)
- Growth Fraction 2 / 3
ratio if dividing cells/ G0 cells
A tissue with a large percentage of proliferating cells and few cells in G0 has a high growth fraction. Chemotherapeutic drugs are much more toxic to tissues that have a high growth fraction than to tissues that have a low growth fraction.
- Stage of cancer growth
Initiation
exposure of cells (especially those actively synthesizing DNA) to enough carcinogens that alter cell's genome-irreversible mu- tation
- Stage of cancer growth
Promotion
induction of unregulated accelerated growth by some agent, chemical, or endogenous hormone
- Stage of cancer growth
Progression
tumor cells get malignant characteris- tics
- Stage of cancer growth
proliferation
increase in the # of cancer cells
- Stage of cancer growth
- / 3