Neoplasia IV Flashcards
What is dysplasia?
Loss in uniformity of individual cells/ their architectural orientation
True or false: dysplasia always develops to CA?
False
How is the CIN grade determined?
By the proportion of epithelial occupied by immature cells
When is a dysplasia termed an invasive carcinoma?
When abnormal cells invade the BM
CIN 1 =?
between 0 and 1/3 =mild dysplasia
CIN 2 = ?
Between 1/3 to 2/3=moderate dysplasia
CIN 3 = ?
2/3 to almost full thickness = severe dysplasia
What is the difference between carcinoma in situ vs CIN 3?
CIN 3 is almost, but not full epithelial thickness.
Carcinoma in situ is full thickness, but not penetrate BM
Carcinoma in situ is only applicable to what type of tissue?
Epithelial
Oral leukoplakia can change into what?
Squamous cell carcinoma
What does Barrett’s esophagus progress to (what type of CA)?
Adenocarcinoma of the esophagus
Chronic atrophic gastritis of pernicious anemia can progress to what CA?
Gastric adenocarcinoma
Chronic ulcerative colitis can progress to what?
Adenocarcinoma of colon
Hepatitis infection can progress to what type of CA?
Macronodular cirrhosis to hepatocellular carcinoma
Simple/complex endometrial hyperplasia can progress to what?
Atypical hyperplasia to endometrial adenocarcinoma
Solar keratosis can progress to what?
Squamous cell carcinoma
Tumors are monoclonal or polyclonal?
Monoclonal
Carcinogenesis involves non-lethal genetic damage. What two places do these come from?
Inherited germline mutations
Acquired mutations
What does the Bax molecule do?
Signals apoptosis
What are the two causes of inherited mutations?
Failure of DNA repair
Mutations in the genome of somatic cells
What three genetic changes must occur for a tumor to develop?
Activation of growth promoting oncogenes
Inactivation of tumor suppressor genes
Alterations in genes that regulate apoptosis
How is generation of heterogeneity of tumors brought about?
Tumor cells mutate/progress to serve different purposes within the tumor (invasive, nonantigenic, GF producer etc)
What are the 7 essential alterations for malignant transformation?
- Self-sufficient growth signals
- Insensitive to growth inhibitory signals
- Evasion of apoptosis
- Limitless replicative potential
- Sustained angiogenesis
- Ability to invade and metastasize
- Defects in DNA repair
What are the four classes of normal regulatory genes?
- Growth promoting proto-oncogenes
- Growth inhibiting tumor suppressor genes
- Genes regulating apoptosis
- Genes regulating DNA repair
What are oncogenes?
Genes the promote autonomous cell growth
What is the two hit mechanism of CA development?
Need to have both alleles mutated to develop CA
Oncogenes are proto oncogenes with what mutation?
Devoid of important regulatory elements
True or false: oncogenes are CA causing genes
True
How are proto oncogenes activated? (3)
Mutation
Chromosomal translocation
Amplification
What are the five types of protooncogenes?
- Growth factors
- GF receptors
- Signal transduction
- Nuclear transcription
- Cell cycle regulators
What is a translocation event? What can this lead to?
When chromosomes trade genetic elements–can lead to over or under expression of gene
What are the two main categories of mutations?
Normal protein overproduced
Mutant protein has an aberrant function
What is ERBB2 (HER-2/Neu) protein?
Amplification receptor for breast and ovarian CA
What is the RET protein? What is it the result of?
GF Receptor for neurotrophic factors
Result of point muation
MEN2A ***
What is CDK4? Mutation is the result of what? What CA is it associated with?
Amplification
Glioblastoma
Melanoma
Sarcoma
What is PDGFRB? Mutation is the result of what? What CA is it associated with?
Receptor for neurotrophic factor
Point mutation
Gliomas, leukemias
What is KIT? Mutation is the result of what? What CA is it associated with?
Receptor for stem cell factor
Point mutation
Gastrointestinal tumors
What is KRAS? Mutation is the result of what? What CA is it associated with?
GTP binding protein
Point mutation
Pancreas, colon, lung CA
What is ABL? Mutation is the result of what? What CA is it associated with?
Non-receptor tyrosine kinase
Translocation
Chronic myeloid leukemia
What is Beta-catemin? Mutation is the result of what? What CA is it associated with?
WNT pathway
Point mutation
Hepatoblastomas, hepatocellular carcinoma
What is BRAF? Mutation is the result of what? What CA is it associated with?
RAS signal transduction
Melanomas
Multiple endocrine neoplasia (MEN-2a/2b) is the result of what? Is this always CA?
Mutation of the RET proto oncogene
can just be hyperplasia
MEN 2a/2b has a familial occurance of what three things?
- Medullary thyroid carcinoma
- Bilateral pheochromocytoma
- Hyperparathyroidism d/t hyperplasia or tumor
What is the chromosomal translocation that is involved in chronic myelogenous leukemia (CML)?
abl on Chromosome 9 translocated to chromosome 22 to produce the philadelphia chromosome (bcr-abl)
The philadelphia chromosome produces what gene translocation? What does this lead to?
22 (Bcr) and 9 (abl) genes
Increases Y kinase activity
What is the drug used to treat chronic myelogenous leukemia? MOA?
Gleevec (imatinib)
Inhibit Y-kinase activity
Burkitt’s lymphoma is the result of what translocation? What does this produce?
Translocation of C-Myc from chromosome 8 to chromosome 14
Causes increased Myc protein production
What are the three types of Burkitt’s lymphoma?
- Endemic
- Sporadic
- HIV associated
What is the translocation of B cell follicular lymphoma? What does this result in
BCL-2 genes translocation (14:18), causing overexpression of BCL-2
What is the function of BCL-2?
Prevents leakage of Cyt C from mitochondria
What is the cause of neuroblastoma?
Amplification of N-Myc gene
How do you identify neuroblastoma?
Homogenously staining regions (HSRs) seen on a karyotype
Low grade squamous intraepithelial lesion = what CIN?
CIN1
High grade squamous intraepithelial lesion = what CIN?
CIN 2-3
There are two autoimmune inflammatory bowel diseases: crohn’s disease and ulcerative colitis? Which one is precancerous?
Ulcerative colitis
What is c-Myc? Mutation is the result of what? What CA is it associated with?
Transcriptional activators
Translocation
Burkitt’s lymphoma
What is n-Myc? Mutation is the result of what? What CA is it associated with?
Transcriptional activator
Amplification
Neuroblastoma, small cell CA of lung
What is Cyclin D? Mutation is the result of what? What CA is it associated with?
Mantle cell lymphoma
Breast and esophageal CA
IgH gene is on what chromosome?
14
What is PDGF-beta chain? Mutation is the result of what? What CA is it associated with?
SIS growth factor
Over expression leads to astrocytoma/osteosarcoma
What is HST? Mutation is the result of what? What CA is it associated with?
FBGF growth factor
Overexpression
Stomach CA
What is TGF-alpha? Mutation is the result of what? What CA is it associated with?
Growth Factor
Over expression
Astrocytomas
Hepatocellular carcinoma
What is HGF? Mutation is the result of what? What CA is it associated with?
GF
Over expression
Thyroid CA