11/2: Anticancer Therapies: Radiation and Drugs Flashcards
What are key properties of cancer cells?
- They reproduce without regard to the normal restraints on cell
growth and cell division
– They invade and colonize areas normally reserved for other cells
What are abnormal cells that grow (increase in mass) and proliferate (divide)?
Tumors or neoplasms
When are tumors considered benign?
If the neoplastic cells do not
become invasive
When are tumors considered cancerous?
If it acquires the ability to invade surrounding tissue at which point it is has become malignant
Malignant tumors often, as a consequence of
their invasiveness, produce cells that break
out of their primary site and form secondary
tumors at other sites called…
Metastases
Is a single mutation sufficient to cause cancer?
No - inherited mutations offer increased risk
What are potential risk factors for cancer?
– Radiation exposure
– UV light from the sun
– Chemicals (carcinogens)
– Life-style (smoking, certain diets)
– Viruses (EBV, HIV, HPV)
The overall incidence of cancer increases with ______
age
During the cell-cycle, the cell has scanning mechanisms to do what?
Detect DNA damage and either repair the damage or result in cell-cycle arrest or cell death (apoptosis)
What protein is a key mechanism in the cellular response to DNA damage?
p53
What is the basic strategy for treating cancer?
To induce so much damage to
the tumor cells via DNA damage (primarily) to
prevent them from dividing and induce cell death
What are the types of radiation therapy?
External beam therapy
Internal Radiation therapy
Photon Therapy
Charged particle or proton therapy
What therapy uses a machine to send high energy beams from outside the body to the tumor area?
External beam therapy
What therapy uses radioisotope given internally, radiation generally only travels a short distance depending upon the isotope and its energy?
Internal radiation therapy
What therapy works either by direct ionization of atoms in the DNA chain or indirectly by ionization of water to form hydroxyl radicals that can then damage DNA?
Photon therapy
What therapy uses a particle accelerator to beam high-energy particles (protons or carbon, boron or neon nuclei). Better ability to precisely localize the radiation
dosage and less damage to surrounding, healthy tissue?
Charged particle or proton therapy
How does doxorubicin hydropcholride (adriamycin) work?
Intercalates between base pairs in the DNA helix,
thereby preventing DNA replication and ultimately inhibiting protein synthesis
How does bleomycin sulfate work?
forms complexes with iron that reduce molecular oxygen to superoxide and hydroxyl radicals which cause single- and double-stranded breaks in DNA
How does cisplatin work?
inducing intrastrand and interstrand DNA cross-links, as well as DNA-protein cross-links, which induce apoptosis
How does methotrexate work?
Inhibition of DNA and RNA syntheses
How does vinblastine work?
inhibits microtubule formation, resulting in disruption of mitotic spindle assembly and arrest of tumor cells
What is a treatment designed to induce, enhance or suppress the immune response. Most applications are designed to stimulate a person’s own immune response to destroy cancer cells that have escaped normal immune surveillance?
Immunotherapy
What is leukemia characterized by?
Increased production/growth of granulocytes in the bone
marrow that then circulate in the blood
What is leukemia caused by?
A chromosomal translocation called the Philadelphia chromosome
