Bolded Cancer Flashcards
(58 cards)
loss of cellular differentiation, irregularities of size and shape of nucleus, loss of normal tissue structure
anaplasia
*cells become pleomorphic - meaning they are variable sizes and shapes
tumor =
new growth (neoplasm)
preinvasive epithelial MALIGNANT tumors of glandular or epithelial origin that have not broken through the basement membrane or invaded the surrounding stroma
recognized in? main type (probably)
carcinoma in situ (CIS)
recognized in cervix, skin, oral cavity, esophagus, and bronchus
glandular epithelial in situ lesions - stomach, breast, endometrium, large bowel
DCIS - ductal carcinoma in situ in breast
- fills mammary ducts, but not progressed to local tissue invasion
- readily treatable
*abnormal cells grown in normal place
substances produced by cancer cells or that are found on plasma cell membranes, in the blood, CSF, or urine
examples?
tumor cell markers
- produced by benign or malignant cells
- hormones, enzymes, genes, antigens, antibodies
- liver tumor - alpha fetoprotein (AFP) blood
- PSA in blood = prostate tumor
If tumor marker, itself, has biologic activity what occurs? Example of this?
symptoms are expressed
- this phenomenon AKA paraneoplastic syndrome
- a type of this is pheochromocytoma = usually benign tumor of the adrenal medulla that causes production of epinephrine and adrenaline (epinephrine) in excess (both considered hormones). This leads to SNS activation - sweating, increased BP, increased HR, h/a
The process by which a normal cell becomes a cancer cell
TRANSFORMATION - CARCINOGENESIS
Transformation/carcinogenesis involves
*all cancers involve malfunction of genes that regulate cell growth and devision
- autonomy - independent control
- lack of contact inhibition - not limited by crowding
- has anchorage independence - normal cells will not grow unless attached to firm surface
- are immortal
cancer metabolism
cancer cells always perform ______?
cancer can grow in hypoxic & acidic environment
glycolysis, even in presence of O2 - allows for more rapid cell growth
cancer stem cells do what? and are what?
self-renew, and are multi-potent meaning they can differentiate into many cell types
cancer causing mutations turn on what?
telomerase and new blood vessel growth
cancer causing mutations…
- prevent apoptosis
- turn on telomerase and new blood vessel growth
- allow tissue invasion and distant metastasis
- activate growth-promotion pathways
- block antigrowth signals
normal genes that direct protein synthesis and cellular growth
proto-oncogenes (non-mutant genes)
*a normal gene that when it undergoes mutation becomes an oncogene
encode proteins in their normal state that positively regulate proliferation
oncogenes (mutant genes)
encode proteins that in their normal state negatively regulate proliferation
anti-oncogenes or TUMOR suppressor genes
encode for proteins that are involved in repairing damaged DNA - responsible for the maintenance
*inherited mutations of these genes can lead to?
caretaker genes
HNPCC (hereditary non-polyposis colorectal cancer) - small area of insertions and deletions that lead to high rate of colon cancer
chromosomal instability in cancer can result in…
a high rate of chromosomal loss, as well as loss of heterozygosity and chromosomal amplification; each of these events can ACCELERATE THE LOSS OF TUMOR-SUPPRESSOR GENES AND THE OVER EXPRESSION OF ONCOGENES
chromosome instability may result in the over expression of
oncogenes
protective caps on each chromosome that blocks cell division and prevents immortality
TELOMERES
*remember that telomeres become smaller and smaller with each cell division and eventually die
cancer cells can activate ______ which leads to unlimited division and proliferation
telomerase - this restores and maintains telomeres
tumor spread by 3 mechanisms
1- direct invasion of contiguous organs known as local spread
2- metastases to distant organs through lymph and blood circulation
3- direct transportation - carried on surgical instrument
a prerequisite for metastasis and the FIRST step in the metastatic process
INVASION: LOCAL SPREAD
- cancer often spreads first to regional lymph nodes and then to distant organs through the blood - can do this through angiogenesis
- invasion then requires that the cancer attach to specific receptors and survive in that environment
what do cancer cells secrete that helps them move through extracellular matrix and basement membranes?
protease
what is EMT
epithelial-mesenchymal transition - increases migratory capacity (decreased adherence), increases resistance to apoptosis, and causes dedifferentiation to a stem cell-like state to favor growth in new environment
Cancer Stages
stage 1- confined to its organ of origin
stage 2- locally invasive (contiguous)
stage 3- advanced to regional structures (nodes)
stage 4- has spread to distant sites
