Unit 3 - Lecture 4 Flashcards
True or False: metastatic neoplasms have the ability to live everywhere.
False - not all neoplasms have the genetic mutations to let them survive in any environment, it is all genetically dependent
How can an epithelial cell metastasize?
normally te cell is squared off and attached to one another, the cell becomes very rounded and there is a loss of vasopolarity, the cell moves through the basement membrane and if it has the right genes to survive it can move through a lymphatic duct and travel
What is the general rule for metastasis?
not all malignant neoplasms metastasize; some metastaize early and some metastasize late
What is an example of a neoplasia that metastasizes early?
a hemangiosarcoma
What is an example of a neoplasia that metastasizes late?
a squamous cell carcinoma
What are the favored metastatic sites via a hematogenous route?
the lung, liver, and adrenal gland
What is the favored metastatic site via a lymphatic spread?
lymph node
What are the not so favored metastatic sites?
skin, skeletal muscle, and the spleen (sometimes)
What tumors do well in the spleen?
round cell tumors
Why are lung, liver, and lymph nodes the organs most commonly affected by metastatic cells?
first capillary bed: filtration, and adhesion (fertile soil)
What is transcoelomic metastasis?
the seeding of the body cavity with tumors
How do transitional cell carcinomas spread?
by surgical instruments in incision
What factors affect tumor production?
growth factors, inflammatory mediators, proteases, and tumor antigens
What is the stromal inflammatory cell response to tumor production?
migration towards the tumor, release of inflammatory mediators, and immune response to the tumor
What is the stromal fibroblast response to tumor production?
production of growth factors, capsule formation, desmoplasia, myofibroblast development, and development of tumor-specific characteristics
What is the stromal extracellular matrix response to tumor production?
release of growth factors and loss of structural integrity
What is the stromal vascular endothelium response to tumor production?
angiogenesis, altered permeability, and production of growth factors
What is the tumor response to the stromal response to tumor production?
altered proliferation rate, altered differentiation characteristics, altered local invasiveness, altered metastatic capability
What are the stimulators of tumor angiogenesis?
vascular endothelial growth factor and basic fibroblastic growth factor
What are the inhibitors of tumor angiogenesis?
angiostatin, endostatin, and vasculostatin
What characteristics do malignant cells acquire?
loss of growth controls and antigen changes
What growth controls do malignant cells lose?
contact inhibition and anchorage dependence
How does contact inhibition normally work?
normally when cells interact with one another, they are like ‘oh hey we should stop growing’
How does anchorage dependence normally work?
normally when cells reach the basement membrane they are usually like ‘hey we should stop growing’
