Lecture 12: Cancer Pharm Flashcards
What are the phases of the cell cycle and what are happening during each of them?
G0 - resting phase (not actively in the cell cycle)
G1 - synthesis of components for DNA synthesis
S - synthesis of DNA
G2 - synthesis of components needed for mitosis
M -mitosis
Why are the G1 and G2 phases important and what can override each of their arrests?
- G1/G2 phases stop inappropriate cell cycle progression and cause either arrest/entry into G0
oncogene activation overrides G1 arrest
tumor suppressor inactivates overrides G2 arrest
What is Primary Chemotherapy and what are the goals of treatment?
- primary treatment for advanced cancer w/no other alternatives OR advanced metastatic cancer
Goals: relieved symptoms, improve quality of life, prolong time to tumor progression
What cancers are curable via Primary Chemotherapy? (4 for adults and 4 for children)
A: Hodgkin/non-Hodgkin, choriocarcinoma, germ cell tumors, AML
C: Burkitt’s, Wilms’ tumor, embryonal rhabdomyosarcoma, acute lymphoblastic leukemia
What is Neoadjuvent Chemotherapy and what are its goals?
- chemotherapy given before surgery or radiation in order to shrink the size of the primary tumor
- helps spare organs and make resection easier
What is Adjuvent Chemotherapy?
- chemotherapy after local treatments, such as surgery or radiation
- helps prevent local/systemic recurrence and improves overall pt. survival
What are Tissue Growth Fraction/Rate and why are they important to consider when providing chemotherapeutic agents?
Growth Fraction - ratio of proliferating to G0 tumors cells
- antineoplastic agents more effective w/high GF
- growth rate of tumors is rapid at first but decreases over time due to the burden of the tumor (central cells of tumor mass usually in G0 phase)
- by surgically removing or irradiating the tumor, it can be shrunk to inc. its GF, making it MORE susceptible to chemotherapeutic agents
What is the Log Cell Kill Hypothesis? How should therapy be given to prevent excessive damage to patients healthy cells?
- antineoplastic surgery follows 1st order kinetics (give dose destroys a constants FRACTION of cells)
- high-dose intermittent therapy allows normal, healthy tissue to recover while killing the tumor cells
What type of infusion is better suited for cell cycle nonspecific vs cell cycle specific antineoplastics?
Nonspecific –> intermittent high dose therapy
Specific –> continuous infusion (has practical limitations), also drugs with high metabolism or excretion
What are Pharmacological Sanctuaries and how can they be dealt with?
- regions where tumor cells are LESS susceptible to antineoplastic agents (CNS/testes)
- can provide antineoplastics via intracavity/intrathetcal/etc treatment that specifically targets that area or bypasses the normal transport constraints of that location
How many cycles of treatment do most curable tumors require?
6-8 cycles of therapy
Inherent chemotherapeutic resistance vs Acquired chemotherapeutic resistance
ICR: drug resistance in absence of prior exposure
- caused by genomic instability
ACR: in response to exposure to give drug or drug class
- due to genomic change causing amp/supp of gene
Multidrug Resistance and p-Glycoprotein
bonus: what drug can potentially inhibit it?
- MDR1; high baseline expression of PGP correlates with primary/inherent resistance to natural antineoplastic agents
- usually seen in tissues with barrier functions or pharmacological barrier sites (BBB/PBB)
- over-expression leads to acquired drug resistance (Verapamil - Ca channel blocker - may inhibit)
What are 5 common adverse effects that occur with nearly all CLASSIC antineoplastic agents?
nausea, vomiting, fatigue, somatitis (mouth swelling/sores), alopecia (hair loss)
- also see myelosuppression, low sperm counts, depressed development in children
What are 3 things that can help decrease the effects of myelosuppression, nausea/vomiting, and skeletal complications?
Hematopoietic agents - myelosuppression
Serotonin receptor antagonist - nausea/vomiting
Biphosphonates - delay skeletal complications
REST AND RECOVERY