Neoplasia Flashcards
what makes a tumor malignant?
invades surrounding tissue and/or metastasizes to other sites in the body
do benign tumors invade surrounding tissues or metastasize?
no
what is in the initiation stage of a cell becoming a tumor?
irreversible alteration of genetic material
what is the progression stage of a tumor becoming a tumor?
gradual development of features of malignancy
malignant transformation of benign tumor
hallmarks: genetic instability and tumor cell heterogeneity
what is germline mutation?
heritable mutations transmitted to offspring and present in all cells
what genetic change is predominantly responsible for tumor development?
driver mutation
what is one thing noncoding RNA has an important role in?
gene expression regulation
what are proto-oncogenes?
normal genes that regulate cell growth and differentiation
what is an oncogene?
a proto-oncogene that is activated by overexpression or mutation
what do cyclin-dependent kinases regulate?
progression of cell through cell cycle
what can a mutation in the receptor tyrosine kinase pathways lead to?
constitutive activation of growth promoting pathways
what do tumor suppressor genes control?
cell cycle
apoptosis
DNA repair
other pathways
can tumor suppressor genes prevent an oncogene from leading to cancer?
yes, if intact, through apoptosis
what is the warburg effect?
even in ample oxygen, utilizes the glycolytic pathway
less energy produced, but provides metabolic intermediates needed to synthesize cellular components
what is apoptosis induced by?
cellular stress, unregulated growth, hypoxia, misfolded proteins
p53 partially
chemotherapy and radiation
what are some important properties of tumor vessels?
leaky and tortuous
how many times can most normal cells divide before senescence?
60-70 times
what can cancer cells express to avoid senescence?
telomerase
can also produce one stem cells after division
what does the location of metastasis depend on?
tumor types, vascular drainage of tumor, tumor cell tropism to other tissues
what is the innate immune response to cancer?
least specific but immediate
natural killer cells and macrophages
what mediates the adaptive immune response to cancer?
cytotoxic T lymphocytes