Final Exam Flashcards
T/F: Carcinogenesis occurs from one or two genetic alterations
False: …results from many genetic alterations
What are the 3 classes of extrinsic carcinogenic agents?
Chemical
Radiant Energy
Microbial
T/F: Direct acting chemical carcinogens require metabolic conversion first.
False: direct acting=no metabolic conversion
indirect acting=requires metabolic conversion
Smoked meat is an example of a direct or indirect acting chemical carcinogen.
Indirect
Aflatoxin B1, found on the shell of ___, typically mutates TP53.
Peanuts
T/F: Following initiator-promotion sequence, the promoter must follow exposure to chemical mutagen.
True
What is irradiation?
High energy waves capable of ionizing atoms and having mutagenic effects.
Hiroshima victims would be an example of what type of external carcinogenic agent?
Radiation carcinogenesis
What is the most common skin cancer?
Basal cell carcinoma
What is the most common form of cancer in the US, (it actually contradicts the statement at the beginning of the packet)?
Skin cancer (yes it says prostate & breast in the beginning of the packet..idk)
What is the Human T Cell lymphotropic virus 1 (HTLV-1)?
Oncogenic virus spread via bodily fluids increasing likelihood of T Cell lymphoma/leukemia
What gene should you associate HTLV-1 with?
TAX gene
What are the 4 oncogenic DNA viruses?
- HPV
- EBV (HHV4)
- HBV, HCV (Hep B and C)
- Kaposi sarcoma herpesvirus (KSHV or HHV8)
What types of HPV cause relatively benign papillomas?
HPV6 and HPV11
What types of HPV cause squamous cell carcinoma?
HPV16 and HPV18
T/F: Human papilloma virus is known for activating retinoblastoma (Rb) and decreasing growth.
False: Rb DEactivation and INCR growth
What was the first oncovirus discovered?
Epstein Barr Virus
Is the EBV more likely to cause T cell or B cell cancers?
B Cell cancers like Hodgkin Lymphoma
Which type of cancer are the Hepatitis B and C viruses associated with?
Liver CA (hepatocellular carcinoma)
HBV and HCV is still prevalent in which two regions of the world?
Africa and SE Asia
Which organism was the 1st “cancer bacteria” discovered and also causes 90% of peptic ulcer disease?
Helicobacter pylori
T/F: 90% of Helicobacter pylori infections lead to cancer.
False: 3% progress to cancer
Which 3 immune cell types have antitumor effector mechanisms?
T Killer cells, NK cells, Macrophages
What is the most common cancer among immunocompromised individuals?
B Cell lymphomas
What is “wasting syndrome”?
(Cachexia) Unexplained weight loss that is irreversible even with nutrition changes; typically accompanies end stage cancer
What are paraneoplastic syndromes?
Features that show up around the time of cancer development
What % of cancer patients exhibit paraneoplastic syndrome?
10-15%
List 3 ways of diagnosing cancer
- Biopsy
- Fine-needle aspiration
- Cytologic smear
T/F: Tumor markers are non-diagnostic enzymes or hormones that can be used for screening for cancer.
True
T/F: The number of genes present correlates to the complexity of the species.
False: otherwise a flea would be more complex than us
T/F: All hereditary disorders are congenital but not all congenital disorders are hereditary.
True: congenital simply means present at birth
What is a point mutation?
a nucleotide base is replaced by another
The insertion/deletion of 1 or 2 nucleotides resulting in an altered reading frame is called a ___ mutation.
Frameshift
What does pleiotropy mean?
A single mutation having various phenotypic effects, ex: Li Fraumeni Syndrome or Marfan Syndrome
In an autosomal dominant disorder with one parent affected, what is the offsprings chance of disorder manifesting?
50% and males/females affected equally
What is reduced penetrance and give an example?
They have the mutation but still phenotypically normal; example is BRCA1 and BRCA2 genes
In an autosomal recessive disorder with both parents being carriers, what % of offspring will be affected? Carriers?
25% normal
50% carriers
25% affected
How are X-linked recessive disorders passed?
By carrier mother, affects 50% of male offspring and 50% of female offspring will be carriers
Genetically, what is Marfan Syndrome?
Aut. Dominant syndrome leading to Fibrillin gene mutation
What does pathognomic mean?
No single sign is definitive of having a disorder
What disorder likely possesses long limbs, joint hypermobility, chest deformities, and an elongated face?
Marfan syndrome
What is pes planovalgus?
Flat feet; can be associated with Marfan Syndrome
What structure is defective in individuals with Ehlers-Danlos Syndrome?
Defective collagen–> hyperextensible skin and hypermobile joints
Is familial hypercholesterolemia an autosomal dominant or recessive disorder and what does it affect?
Autosomal dominant defect of LDL receptor
Which subtype of familial hypercholesterolemia has a childhood onset and is much more severe?
Homozygous; (heterozygous is adult onset and less severe)
What are xanthomas and which disease are they characteristic to?
Cholesterol deposits on tendons seen in familial hypercholesterolemia
What is the likely cause of death in individuals with Marfan syndrome?
Ruptured aorta
T/F: Cystic fibrosis is an autosomal dominant disorder affecting the CFTR gene.
False: autosomal recessive
Which disorder would likely show a positive Steinberg sign: Cystic Fibrosis, Ehler-Danlos, or Marfan Syndrome
Marfan Syndrome
What is the most lethal genetic disease in Caucasians?
Cystic fibrosis
How do people with Cystic Fibrosis usually die?
Chronic pulmonary infections
Phenylketonuria is an autosomal ___ disorder resulting in the accumulation of ___.
Recessive; phenylalanine
A “salty kiss” may be the first sign a baby may have ___ ___.
Cystic Fibrosis
Which genetic disorder can exhibit a musty or mousy odor to their urine/sweat?
Phenylketonuria (PKU)
Why do individuals with phenylketonuria exhibit decreased pigmentation that can be confused for albinism?
Lack phenylalanine, a precursor for tyrosine (which is a precursor for melanin)
Galactosemia is an autosomal ___ disorder affecting what enzyme?
Recessive; GALT
In babies with phenylketonuria, mental disabilities can be avoided if what is restricted and what is supplemented?
Restrict phenylalanine since it can’t be broken down…
supplement tyrosine
What should be restricted in individuals with galactosemia?
Galactose
Which organ is likely to be enlarged in babies with galactosemia?
Liver resulting in outward jaundice
Lysosomal storage diseases lack which enzymes?
Lysosomal enzymes (autosomal recessive)
What are the 5 LSD’s?
Tay Sach's Niemann Pick Types A & B Niemann Pick Type C Gaucher Mucopolysaccaridosis
The inability to metabolize Gm2 gangliosides is characteristic of which LSD?
Tay-Sach’s Dz
Which enzyme is mutated with Tay Sach’s Dz?
Hexosaminidase A enzyme
This disease with cherry red central macula is typically fatal by age 2-3.
Tay Sach’s Dz
What accumulates in Niemann-Pick Dz Type A&B?
Sphingomyelin accumulates –> enlarged spleen and liver
Which is most severe and typically fatal by age 3: Niemann Pick Type A, B or C?
N.P Type A
Niemann Pick Type B varies from A in that it shows no ____ damage.
Neuronal
Which is the most common and has defective lipid transport: Niemann Pick Type A, B or C?
N.P Type C
What 3 things accumulate in Niemann Pick Type C?
- Cholesterol
- Gm1 gangliosides
- Gm2 gangliosides
What is mutated in Niemann Pick Type C?
NPC1 or NPC2
____ gene is mutated in Gaucher Dz leading to the accumulation of ____.
Glucocerebrosidase gene mutated;
Glucocerebrosides accumulate
T/F: Gaucher cells are enlarged liver cells
False: enlarged phagocytes but a common symptom of Gauchers is hepatosplenomegaly
What is pancytopenia?
reduction in all blood cells resulting in anemia and easy bruising (associated with Gaucher’s Dz)
99% of individuals with Gauchers have the Type__ which is less severe with no neuro disturbances.
Type 1
T/F: Wrinkled tissue paper cytoplasm and Erlenmeyer’s flask deformity are characteristic of Gaucher Dz.
True
What 2 LSD’s are Ashkenazi Jews particularly vulnerable to?
- Tay Sach’s Dz
2. Gaucher’s Dz
What is mucopolysaccharidosis?
Group of disorders regarding deficiency in ECM breakdown enzymes
What are the two types of mucopolysaccharidosis’?
Type 1 (Hurler) Type 2 (Hunter)
Alpha-L-iduronidase deficiency=____ Syndrome
L-iduronate sulfatase deficiency= ____ Syndrome
Alpha…=Hurler
L-idur….=Hunter
Which syndrome is X-Linked: Hurler or Hunter?
Hunter
Which syndrome is lethal by 6-10 years: Hurler or Hunter?
Hurler, Hunters is more mild
Which syndrome accumulates heparin sulfate and dermatan sulfate: Hurler or Hunter?
Both!
What is the shorter name for glycogen storage diseases?
Glycogenoses
Which autosomal recessive disorder involves abnormal glycogen metabolism?
Glycogenoses
Match the following:
von Gierke Dz muscle phosphorylase
McArdle Dz glucose 6 phosphatase
Pompe Dz lysosomal acid maltase
von Gierke-glu6phosphatase
McArdle-muscle phosphorylase
Pompe-lysosomal acid maltase