Module 3 - Oncology Flashcards
6 essential characteristics of cancer
- enabling replicative immortality
- inducing angiogenesis
- resisting cell death
- sustaining proliferative signaling
- evading growth suppressors
- activating invasion and metastasis
neoplasm definition
a new growth, may be benign or malignant
neoplasia definition
a process of expansion d/t defects in the molecular controls that regulate cellular proliferation and/or death
cancer terminology definition
any malignant neoplasm
tumor definition
nonspecific term meaning lump or swelling
hyperplasia definition
increase in organ/tissue size d/t an increase in the NUMBER of cells
metaplasia definition
an adaptive substitution of one type of tissue to another type of tissue
dysplasia definition
an abnormal cellular proliferation in which there is loss of normal architecture
anaplasia definition
a loss of structural differentiation
desmoplasia definition
the formation and proliferation of connective tissues and cells
carcinoma definition
malignant neoplasm of epithelial cell origin
adenoma definition
epithelial neoplasm which produces or is derived from GLANDULAR tissue
papilloma definition
benign tumor of surface epithelium in which neoplastic cells grow outward in finger-like fibrovascular stalks
teratoma definition
a germ cell neoplasm made of several differentiated cell/tissue types (that are not normally present at the site)
sarcoma definition
malignant neoplasm with origin in mesenchymal tissues or its derivatives (connective tissues- muscles, nerves, bones, etc)
lymphoma and leukemia definition
malignant neoplasms of hematopoietic tissues; leukemia: bone marrow
lymphoma: lymphatic system
blastoma definition
cancer caused by malignancies in precursor cells (blasts)
melanoma definition
cancer of pigment (melanin) producing cells, melanocytes
Which type of cell diagnoses Hodgkin’s Lymphoma?
Reed-Sternberg cells
Staging vs Grading of carcinomas
Staging (TNM, 0-IV): based on tumor size, location, and number.
Grading (0-4): based on differentiation of tumor cells and tissue.
What does HER2 stand for?
Human Epidermal Receptor-2
proto-oncogene
What is the purpose of Oncotype Dx and Mammaprint?
Gene signatures that measures the expression of specific genes to:
1. predict recurrence of breast cancer
2. prevent overtreatment
do NOT drive indications for specific therapies
Steps of metastasis
(primary neoplasm) progressive growth, vascularization, invasion, detachment, embolization, survival in circulation, arrest, extravasation, evasion of host defense, progressive growth (metastasis)
Summary Staging
- In situ: only in layer of cells where developed.
- Localized: limited to organ where began.
- Regional: spread to nearby lymph nodes or tissues/organs.
- Distant: spread to distant lymph nodes or tissues/organs.
TNM Staging System (abbreviation meaning)
T: primary tumor
N: regional lymph nodes
M: distant metastasis
(0-4 each based on extent)
How does Rous Sarcoma Virus (RSV) lead to tumor formation?
RSV is a retrovirus that encodes a protein (v-Src) that mimics the eukaryotic protein Src. These proteins drive proliferation and tumor progression (oncogenes).
Which type of cancer is not a hormone-responsive disease?
Ovarian cancer (although ovaries are hormone-producing organs)
What hormones are primarily targeted in the treatment of hormone-dependent cancers?
estradiol (breast, endometrial)
dihydrotestosterone (prostate)
What is the starting point for steroid hormone biosynthesis?
Cholesterol
What are the two major classes of anti-estrogen therapy?
- Aromatase inhibitors (stop estrogen production)
2. SERMs (stop estrogen function)
Tamoxifen MOA
SERM (prodrug activated by CYP2D6)
- in mammary gland: binds ER and blocks estrogen-dependent cell proliferation
- in bone: activates ER to treat osteoporosis
Tamoxifen indication
prevention/treatment for ER+/PR+ breast cancer
- *effective in BOTH pre- and post-menopausal women
- *less effective with CYP2D6 variant
Estrogen agonist/antagonist effects
Agonist effects: -increases incidence of endometrial cancer -preservation of bone density -blood clots Antagonist effects: -hot flashes
Where are Tamoxifen and Raloxifene estrogen receptor (ER) agonists vs antagonists?
Antagonist: breast, brain, uterus (raloxifene)
Agonist: blood, bone, uterus (tamoxifen)
What do SERM and SERD stand for?
SERM: Selective Estrogen Receptor Modulator
SERD: Selective Estrogen Receptor DownModulator
Where is the principle source of estrogen in postmenopausal women?
Adipocytes
Aromatase inhibitor MOA
MOA: inhibit enzyme that produces estrogen
(androgens and progesterone not affected)
Use: estradiol suppression in POSTMENOPAUSAL women
Non-steroidal Aromatase Inhibitors (list, MOA, indication)
Letrozole and Anastrozole
- competitive inhibitors of aromatase
- treatment of ER+ breast cancer in postmenopausal women
Steroidal Aromatase Inhibitors (list, MOA, indication)
Exemestane
- suicide inhibitor of aromatase (mimics androstenedione)
- treatment of ER+ breast cancer in postmenopausal women
medrooxyprogesterone acetate (Provera) MOA and indication
MOA: progesterone agonist that suppresses estrogen production and induces differentiation of endometrium
Indication: prevention of endometrial cancer in postmenopausal women
LHRH analogs in women (list, MOA, indication)
Leuprolide acetate and Goselerin
MOA: GnRH mimics that downregulate pituitary LHRH receptors (severe loss of estrogen w/in 3-4 weeks)
Indication: PREmenopausal breast cancer
LHRH analogs SE in women
Acute administration: surge of LH/FSH (agonist/flare effect); transient worsening of sx
Chronic administration: loss of estrogen w/in 3-4 weeks (hot flashes, sexual dysfunction)
Fulvestrant MOA and indication
SERD; pure ER antagonist
MOA: binds to ER and degrades receptor
Indication: ER+ metastatic breast cancer in post-menopausal women
Difference between SERM and SERD
SERMs and SERDs bind and modulate estrogen receptors
SERDs also degrade estrogen receptors
List SERM and SERD drugs
SERM: tamoxifen, raloxifene
SERD: fulvestrant
Which hormonal therapies can be used to treat breast cancer in premenopausal women?
- LHRH agonists (goserelin, luprolide)
2. Tamoxifen (SERM)
Which hormonal therapies can be used to treat breast cancer in postmenopausal women?
- tamoxifen (SERM)
- nonsteroidal aromatase inhibitors (anastrozole, letrozole)
- steroidal aromatase inhibitor (exemestane)
- pure anti-estrogen; SERD (fulvestrant)
- progestin (megestrol acetate)
LHRH analogs in men (list, MOA, indication)
Leuprolide acetate, Goselerin
MOA: prolonged treatment decreases LH receptors and leads to potent loss of T. production within 3-4 weeks (“chemical castration”)
Indication: palliative treatment of advanced prostate cancer
LHRH analogs in men SE
Acute administration: surge of LH/FSH (agonist/flare effect); transient worsening of sx
Chronic administration: potent loss of testosterone; gynecomastia, sexual dysfunction (“feminization”)
LHRH antagonists (list, MOA, indication)
Abarelix, Degarelix
MOA: blockade of GnRH receptors decreases testosterone production; immediate effects vs LHRH agonists (avoids tumor flare)
Indication: treatment of prostate cancer
Androgen Antagonists (list, MOA, indication)
Flutamide, Nilutamide, Bicalutamide, Enzalutamide
MOA: pure AR antagonist- blocks DHT binding (prevents nuclear translation of DHT-AR and binding to DNA)
Indication: treatment of metastatic prostate cancer
Androgen Antagonists SE
- Gynecomastia, hot flashes, impotence (reversible upon d/c)
- Acute hepatotoxicity (flutamide; rare, fatal)
- Diarrhea (flutamide)
Abiraterone (indication, MOA, SE)
Indication: treatment of prostate cancer
MOA: steroid analogue that inhibits 17 a-hydroxylase and 17,20 lyase
-prevents hormone synthesis from much higher step
SE: increased cholesterol
5-alpha-reductase inhibitors
finasteride, dutasteride
- may delay growth of benign prostate tumors
- prolonged use may select for more aggressive AR-independent tumors
What is the goal of endocrine (hormonal) therapies?
To prolong progression (not curative)
-all patients that initially respond will develop resistance
Which breast cancer treatment is administered as an IM injection once per month?
Fulvestrant (SERD)
Types of kinase inhibitors
Type I: bind active conformation of kinase
Type II: bind inactive conformation of kinase
Type III and IV: bind allosteric pocket
Covalent: irreversibly bind cysteine residue (blocks ATP binding site)
List the first generation EGFR inhibitors and their MOA
Erlotinib and Gefitinib
MOA: small molecule TYPE 1 competitive inhibitors of EGFR tyrosine kinase (turn off proliferative signal)
Indication of Erlotinib and Gefitinib?
Treatment of EGFR-mutant metastatic NSCLC
require positive Cobas EGFR Mutation Test
What does EGFR stand for?
Epidermal Growth Factor Receptor
What does NSCLC stand for?
Non-Small Cell Lung Cancer
Where do tyrosine kinase inhibitors bind?
diffuse through membrane and bind intracellularly on the tyrosine kinase domain
What mutation causes resistance to Erlotinib and Gefitinib?
T790M mutation
What is the second generation EGFR inhibitor and its MOA/indication?
Afatinib
MOA: forms covalent bond with Cys797 on EGFR
Indication: EGFR-mutant NSCLC
(does not benefit patients with T790M mutation)
What is the third generation EGFR inhibitor and its MOA/indication?
Osimertinib
MOA: covalent kinase inhibitor specific for T790M mutant EFGR
Indication: metastatic NSCLC that has progressed on other EGFR inhibitor therapy and tests + for the T790M mutation
What does HER2 stand for?
Human EGF Receptor 2 (ErbB2)
proto-oncogene genomically amplified in breast and gastric cancers
Lapatinib MOA/indication
MOA: small molecule type 1 TKI that inhibits both EGFR and HER2 signaling
Indication: treatment of HER2+ breast cancer and gastric cancer that have failed other therapies (such as trastuzumab)
Herceptin (brand)
trastuzumab (generic)
What is a side effect of blocking HER2?
Decrease in cardiac function (reversible)
What does VEGFR stand for?
Vascular Endothelial Growth Factor Receptor
critical to tumor angiogenesis
Which drugs target cMET and what are their indication?
Crizotinib and Cabozantinib
MOA: Type II kinase inhibitors of cMET
Indication: treatment of lung cancers in which cMET is amplified
What does HGF stand for?
hepatocyte growth factor
-ligand of cMET (amplified in some lung cancers)
What cancer is associated with the BCR-Abl fusion protein?
chronic myelocytic leukemia (CML)
How does the BCR-Abl protein result in malignancy?
*Abl protein is a tyrosine kinase
BCR-Abl protein’s kinase activity is constitutively active (very common in CML)
What stem cell factor is associated with GIST and what does GIST stand for?
c-Kit
(tyrosine kinase)
Gastrointestinal Stromal Tumor
Gleevec (brand)
imatinib (generic)
What does CML stand for?
chronic myelocytic leukemia
associated with BCR-Abl fusion protein
What is the MOA and indication of Imatinib?
(Gleevec)
MOA: type II small molecule inhibitor of Abl tyrosine kinase (also inhibits c-Kit)
Indication: treatment of CML and GIST
What is the MOA and indication of Ponatinib?
MOA: type II tyrosine kinase inhibitor effective against all major mutant forms of BCR-Abl, including T315 gatekeeper mutation
Indication: treatment of CML
What are the BCR-Abl inhibitors that are indicated in the treatment of CML?
- Imatinib
- Nilotinib
- Ponatinib
- Dasatinib
- Bosutinib
What cancer is associated with the ELM4-ALK fusion protein?
Occurs in 6% of non-small cell lung cancers (NSCLC)
How does the ELM4-ALK protein result in malignancy?
ALK is a tyrosine kinase that becomes constitutively active when fused to ELM4
(results in NSCLC)
What does ALK stand for?
Anaplastic Lymphoma Kinase
tyrosine kinase similar to EGFR that may inappropriately fuse to ELM4 gene and cause NSCLC
Crizotinib MOA and indication
targets non-specific kinase domain:
- inhibits ALK and treats NSCLC caused by EML4-ALK fusion gene
- inhibits cMET (HGF receptor) and treats lung cancer
Sorafenib MOA and indication
general kinase inhibitor
MOA: inhibits RAF, VEGFR, and p38 MAPK
Indication: advanced renal cell carcinoma, or hepatocellular carcinoma
Vemurafenib (indication, MOA, SE)
Indication: metastatic melanoma (requires B-Raf mutation diagnostic test)
MOA: selective inhibitor for B-Raf with V600E mutation, but also activates normal B-Raf and could promote tumor growth if wild-type enzyme
SE: skin legions and arthralgias
Dabrafenib (indication, MOA)
Indication: Braf V600E/K mutant metastatic melanoma (in combo with Trametinib)
MOA: second generation Braf-V600 inhibitor
Trametinib (indication, MOA, SE)
Indication: Braf V600E/K mutant metastatic melanoma (in combo with Dabrafenib to prevent toxicities with wild-type Braf)
MOA: inhibits kinase activity of MEK1 and MEK2; only approved Type III allosteric inhibitor**
SE: rash
PI3K
Phosphoinositide 3-Kinase
lipid kinase that leads to downstream activation of PKB (needed for cancer cell survival)
Idelalisib (indication, MOA)
Indication: relapsed chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma
MOA: PI3K inhibitor (first approved lipid kinase inhibitor)
Braf inhibitors (indication, list)
Indication: Braf-mutant melanoma
- Sorafenib
- Vemurafenib
- Dabrafenib (in combo with Trametinib)
What is the only approved Type III allosteric inhibitor and what is its indication?
Trametinib
Indication: Braf V600 mutant melanoma in combination with Dabrafenib (if no prior Braf inhibitor therapy)