Pathology Flashcards
Mutation of the ___ gene is the FIRST step in the classic adenoma-to-carcinoma sequence; it is found in most cases of SPORADIC colon cancer and in all patients with Familial Adenomatous Polyposis
APC tumor suppressor
The microsatellite instability pathway is characterized by mutations in DNA _____ genes (MLH1 and MSH2) and is implicated in the development of hereditary nonpolyposis colorectal cancer (Lynch syndrome).
mismatch repair
Aflatoxin exposure is associated with a G:C → T:A transversion in the p53 gene, which greatly increase the risk of developing _____ carcinoma.
hepatocellular
Osteosarcomas typically form when a mesenchymal stem cell develops mutations in the following genes:
RB & TP53
Tumor Supressor Genes
Activating mutations of ___ are responsible for most cases of hairy cell leukemia & Melanomas
BRAF
Activating mutations in the ___ proto-oncogene are common in colorectal cancer and non-small cell lung cancer. It encodes for a GTPase that relays cellular growth and proliferation signals from outside the cell.
KRAS
Germ-line mutations of the ___ proto-oncogene cause multiple endocrine neoplasia type 2
RET
most common primary bone malignancy in children and young adults. It occurs most frequently at the metaphyses of long bones and presents with local pain and swelling. Most cases are associated with sporadic or inherited mutations in RB1 (hereditary retinoblastoma) and TP53 (Li-Fraumeni syndrome).
Osteosarcoma
TP53 tumor suppressor gene, which encodes for P53, a protein that regulates cell-cycle progression and maintains genomic integrity by activating DNA repair following damage. Germ-line mutations are associated with ___ syndrome
Li-Fraumeni syndrome
In humans, ____ is concentrated in liver cells; elevated levels suggest an obstructive biliary process.
alkaline phosphatase
zinc-containing enzymes that degrade/penetrate components of the extracellular matrix (ECM) and basement membrane
Metalloproteinases
Tumor Cell Invasion:
Tumor cells detach from surrounding cells (↓cadherins)
Tumor cells adhere to the basement membrane (↑laminin)
Tumor cells invade the basement membrane (metalloproteinases)
Detach
Adhere BM
Degrade BM
BRCA1 and BRCA2 in particular are involved in repair of double-stranded ___. A mutation increases the risk of developing breast and ovarian cancer.
DNA breaks
Epidermal growth factor receptor (EGFR) stimulation leads to downstream activation of ___, a membrane-bound GTP-binding protein that stimulates cellular growth and proliferation.
KRAS
stimulation leads to downstream activation of KRAS, a membrane-bound GTP-binding protein that stimulates cellular growth and proliferation.
Epidermal growth factor receptor (EGFR)
Epidermal growth factor receptor (EGFR) stimulation leads to downstream activation of KRAS, a membrane-bound ___-binding protein that stimulates cellular growth and proliferation.
GTP
Unchecked cellular growth via overexpressing ___ or by developing constitutive activating mutations in the ___ proto-oncogene.
EGFR
KRAS
Lipopolysaccharides trigger the degradation of __ inhibitor protein allowing it to release NFkB so it can enter the nucleus and stimulate the transcription of cytokines like TNF alpha and IL-1
IkB
Janus kinase 2 (JAK2) is a non- receptor tyrosine kinase involved in the signaling pathway for myeloproliferation. Constituent activation is associated with ___ disorders.
primary myeloproliferative
The principal protein that stimulates the production and release of neutrophils from the bone marrow.
Granulocyte colony-stimulating factor (G-CSF)
An essential step in the MHC I processing of a virus is the breakdown of intracellular viral proteins by the ___ pathway.
ubiquitin proteasome
The key growth factors that promote ___ in neoplastic and granulation tissue are vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF).
angiogenesis
The key growth factors that promote angiogenesis in neoplastic and granulation tissue are __ & __
vascular endothelial growth factor (VEGF)
fibroblast growth factor (FGF)
Require gain-of-function mutations to become cancerous. They typically encode proteins that promote cell division (eg, growth factors, receptors, signal transduction factors). Only one allele must be damaged to increase the risk of cancer formation.
Protooncogenes (RET)
Loss of function mutation results in unregulated growth. They typically encode proteins involved in apoptosis or inhibition of cell cycle progression; both alleles must be inactivated to increase the risk of malignancy.
Tumor suppressor genes (TP53, RB)
Enlarged, ulcerated left tonsil or nontender, nonmobile left neck mass (cervical/supraclavicular) with Squamous Cell Carcinoma is caused by what virus most likely?
HPV
HPV produces viral oncoproteins __ & __
E6 and E7
HPV viral protein __ binds to __, a tumor suppressor protein that normally inhibits the proliferation of cells with genetic abnormalities.
E6–p53
(Ubiquitination of the E6-p53 complex induces degradation of p53, leading to unregulated cellular growth) E6 is like a SUICIDE BOMBER
Inactivation of ___ protein activity by human papillomavirus can lead to the formation of head and neck squamous cell carcinoma.
retinoblastoma
HPV viral protein __ binds to __ protein, which results in the unbinding of E2F (a transcription factor that induces cell cycle activation) allowing it to move into the nucleus and cause unregulated DNA replication and cyclin-mediated cell cycling.
E7
retinoblastoma (Rb)
E7–Rb complex displaces what transcription factor from being bound to Rb?
E2F
How does HPV first establish infection in the cells?
Enters through micro-tears in the squamous cell epithelium and integrates it’s genes into the host cell genome to code for viral oncoproteins E6 and E7
Hemangioblastoma, clear cell renal carcinoma, pheochromocytoma
von Hippel-Lindau syndrome
MSH2/6
MLH1
PMS2
mutations are associated with that cancers (3)
Lynch Syndrome
Colorectal, Endometrial, Ovarian cancers
Lynch the CEO
tumors contain neoplastic cells that are morphologically and architecturally similar to normal cells in the tissue of origin.
Well differentiated (low-grade)
tumors contain neoplastic cells that lack most of the characteristic features of the original tissue.
poorly differentiated (high-grade)
Neoplastic cells that demonstrate a complete lack of differentiation are termed
anaplastic
Tissue with: Mitotic figures Giant cells variation in size/shape of cells (pleomorphic) Loss of polarity (no architecture/sheets/nests) and/or High nucleus: cytoplasm ration Deep staining (hyperchromatic)
anaplastic
Disordered cell growth
Dysplasia
switching from one differentiated cell type to another often in response to irritants (eg, tobacco smoke or gastric acid).
Metaplasia
Li-Fraumeni Syndrome is autosomal ____
dominant
Li-Fraumeni syndrome is caused by an autosomal dominant mutation in the tumor suppressor gene ___.
TP53
Leukemia, sarcomas, and tumors of the breast, brain, and adrenal cortex are most common.
Li-Fraumeni syndrome
an autosomal-DOMINANT hereditary disorder that results in the formation of innumerable colonic polyps and a nearly 100% risk of colorectal cancer.
Familial adenomatous polyposis
is associated with hereditary nonpolyposis colorectal cancer, but patients do not have extensive polyposis in the colon but are very likely to develop colon cancer (from dysplasia in flat colonic mucosa).
Lynch syndrome
caused by a DNA Mismatch Repair gene loss of function
vs
caused by protein that degrades beta-catenin= increased cellular concentrations of beta-catenin, which activates Wnt pathways = hyperproliferation
Lynch (a few polyps in the colon)
vs
FAP (Hundreds of polyps in the colon)
Both cause Colon Cancer
Immunoglobulin gene rearrangement is impaired in
hyper-IgM syndrome
Deficiency of the ___ complement component causes increased susceptibility to encapsulated bacteria
(S. pneumoniae, H. influenzae, Neisseria) and also to developing SLE
C1
Kartagener syndrome is a form of primary ciliary dyskinesia characterized by the triad of situs inversus, chronic sinusitis, and bronchiectasis. It occurs due to mutations that impair the structure or function of
cilia
The Rb protein, in its active (dephosphorylated) form, regulates cell cycle progression by preventing the transition from the ____
G1 phase to the S phase
___ and DNA polymerase are enzymes involved in DNA synthesis, which occurs during the S phase of the cell cycle.
Dihydrofolate reductase
__ of the Rb protein inactivates it (due to it releasing EF2) allowing cells to progress through the G1/S checkpoint and proliferate.
Phosphorylation
__-positive breast cancers have a higher risk of disease recurrence and worse prognosis
HER2
The ___ oncogene codes for a human epidermal growth factor (EGF) receptor with tyrosine kinase activity in the intracellular domain. It is known to play a role in the activation of transduction pathways that control epithelial growth and differentiation. These epithelial cell carcinomas have increased proliferation and resistance to apoptosis.
HER2
Estrogen and progesterone receptors are intracellular receptors that are frequently overexpressed in patients with breast cancer. Stimulation of these hormone receptors increases
cellular proliferation
In cancer-related cachexia, high levels of pro-inflammatory cytokines lead to increased ___ of sarcomeric muscle proteins, which in turn leads to extensive skeletal muscle loss.
ubiquitination
Thought to mediate paraneoplastic cachexia in humans by suppressing appetite and increasing basal metabolic rate.
Tumor necrosis factor-α
The RET proto-oncogene codes for a membrane-bound ____ receptor involved in cell cycle regulation. Constitutive activation of the receptor leads to unregulated cellular proliferation.
tyrosine kinase
___ cancer is a neuroendocrine tumor that arises from calcitonin-secreting C (parafollicular) cells.
Medullary thyroid
Adenoma to Carcinoma sequence:
Progression from normal mucosa to a small adenomatous polyp (adenoma) = ___ mutation
Increase in the size of the adenoma due to unregulated cell growth = ___ mutation
Malignant transformation of adenoma into carcinoma = ____mutation
APC
KRAS
TP53
Bony pain in an older man with osteoblastic lesions on imaging is highly suspicious for ___ cancer.
prostate
Metaplasia can lead to subsequent ___ and malignant transformation.
dysplasia
Tumor associated with marker:
Alpha Fetoprotein
HCC
Non seminomatous Germ Cell
Tumor associated with marker:
CA 19-9
Pancreatic
Tumor associated with marker:
CA 125
Ovarian
Tumor associated with marker:
Carcinoembryonic antigen
GI
Colorectal, etc.
Tumor associated with marker:
hCG
Choriocarcinoma
Seminomatous Germ Cell
Proto-Oncogene associated cancer:
ALK
Large cell lymphoma
Non-small cell lung cancer
Proto-Oncogene associated cancer:
BRAF
Melanoma
Proto-Oncogene associated cancer:
HER1
Squamous cell lung cancer
Proto-Oncogene associated cancer:
HER2/neu
Breast and Ovarian cancer
Proto-Oncogene associated cancer:
MYC
Neuroblastoma
Small cell lung cancer
Proto-Oncogene associated cancer:
RET
Medullary Thyroid Cancer
Pheochromacytoma
Anti-oncogenes (Tumor suppressors) associated cancers:
APC/ Beta Catenin
Colorectal cancer
Pancreatic Cancer
Gastric Cancer
FAP
Anti-oncogenes (Tumor suppressors) associated cancers:
BRCA1/2
Breast cancer
Ovarian cancer
Anti-oncogenes (Tumor suppressors) associated cancers:
RB
Retinoblastoma, Osteosarcoma
Anti-oncogenes (Tumor suppressors) associated cancers:
VHL
RCC
Anti-oncogenes (Tumor suppressors) associated cancers:
WT1
Wilms Tumor
Colorectal cancer
Desmoids/Osteomas
Brain Tumors
Familial Adenomatous Polyposis (APC gene)
ABCDO
APC, Brain, Colorectal, Desmoid/Osteoma
Hemangioblastomas
Clear cell renal carcinoma
Pheochromacytoma
Von Hippel Lindau
VHL gene
Pituitary adenomas
Pancreatic adenomas
Parathyroid adenomas
MEN 1
Medullary Thyroid cancer
Pheochromacytoma
Parathyroid Hyperplasia
MEN2a
Cholangiocarcinoma (gallbladder)
Pancreatic adenoma
RAS (GTP binding protein)
Burkitt Lymphoma proto-oncogene
MYC (transcription factor)
Lung adenocarcinoma proto-oncogene
ERBB1
(EGFR)
(Receptor Tyr Kin.)
CML proto-oncogene
ABL
non-receptor Tyr. Kin
Hairy cell Leukemia
Melanoma
proto-oncogene
BRAF
RAS signal transduction
Li- Fraumeni Syndrome
Most Cancers
Tumor suppressor gene
TP53
Genomic Instability
Tumor suppressor gene:
RB function
G1/S transition inhibitor
Tumor suppressor gene:
VHL function
Ubiquitin ligase component
Tumor suppressor gene:
APC function
Beta catenin
Wnt signaling pathway
Tumor suppressor gene:
TP53 function
Genomic Stability
proto-oncogene function
BRAF
Ras signal transduction
proto-oncogene function
RAS
GTP binding protein
What type of genes are:
RAS, MYC, ERBB1, ABL. BRAF
Proto-oncogene
1 hit gain of function
BRCA1/2
APC, TP53, RB, WT1, VHL
Tumor suppressor genese
2 hit loss of function
Osteoblastic bone metastases are associated with what 3 cancers
Prostate
SMALL cell Lung
Hodgkin
Osteolytic bone metastases are associated with what 5 cancers
Multiple Myeloma NON-Small cell Lung Non-Hodgkin Renal Cell carcinoma Melanoma