enzyme immunoassay for tumor markers Flashcards
biomarkers that are used to screen, diagnose, stage, and monitor different types of cancer
tumor markers
ideal tumor marker should be (3)
- highly specific to a given type of cancer
- correlates with the tumor burden, accurately reflecting cancer progression/regression
- hughly sensitive to avoid false positive results
t/f: tumor markers are not the gold standard for the diagnosis of cancer
t
identification of tumor markers such as afp and cea is based on the classic __ technique which uses the high affinity protein-ligand interaction system, __
sandwich elisa, biotin-streptavidin
__, __, __, and __ are delivered into the solid surface of microtiter wells that are pre-coated with __
calibrators, controls, serum samples, and antibody enzyme conjugate, streptavidin
sandwich complex is made up of (4)
anti-AFP/anti-CEA enzyme labelled antibody, AFP/CEA antige, streptavidin, biotinylated anti-AFP/anti-CEA antibody
the intensity of the colored product is __ to the concentration of the tumor antigen in the specimen
directly proportional
major plasma glycoprotein with a molecular weight of 70kDa
alpha-fetoprotein (AFP)
fetal form of serum album
AFP
t/f: AFP is synthesized by emryonic hepaticytes and cells in the yolk sac during fetal development
t
production of AFP preaks in the __ of pregnancy and rarely persists in the maternal circulation following birth
second trimester
significant high afp levels
> 100,000 ng/mL
significantly high afp levels are observed in
neonates
afp levels rapidly fall below __ around __ days after birth and gradually return to normal over the first year
100ng/mL, 150 days
afp becomes abnormally elevated in maternal serum and fetal amniotic fluid in cases of __ such as __ and __
fetal neural tube defects, spina bifida, anencephaly
high afp levels are also present in approximately __% of patients with __ and __% of patients with __
70% - hepatocellular carcinoma
50-70% - nonsemiinomatous testicular tumors
<8.5 ng/mL
100-350 ng/mL
> 350 ng/mL
an oncofetal glycoprotein synthesized in the gastrointestinal tissues and pacreas during normal fetal development
carcionoembryogenic antigen (CEA)
molecular weight of CEA
200kDa
marker used to monitor the progress of tumors in patients diagnosed with colorectal cancer
CEA
<5 ng/mL
<10 ng/mL
