Exam 1 Cancer/Genetics Flashcards
Malignant
Grow in uncoordinated fashion, proliferates erratically, cancerous , Poorly differentiated (anaplasia)
Growth rate can be slow or fast
Benign
Non cancerous, well differentiated, resembles tissue of origin, slow and progressive growth rate
What does it mean to Metastasize
Ex. of what type of cell can Metastasize
Travel through the blood stream Via Lymphatic system and bloodstream
Malignant
What system is used to consider neoplasm ?
TNM System
What is neoplasm?
An abnormal mass of tissue that forms when cells grow and divide more than they should
may be benign (not cancer) or malignant (cancer)
What are the stages of the cell cycle?
G0- cell is at rest / not engaged
- G1- cell goes into cell cycle and prepares for DNA replication
- S- synthesis of structures occur/ New DNA is formed for mitosis
- G2- check point; DNA damage is being sensed here- > can delay the cycle/ cell will try to repair damage- if the DNA is damaged there is no repair think apoptosis
- M- mitosis is completed and 2 daughter cells are created.
What is cytokinesis ?
Process where the parent cell divides into to daughter cells
Explain which part of the cell cycle does cancer cells fail
There is no G0, G2.
It inactivates the DNA in repair in G2
So, if there is damage the cycle continues w/o control
What are the stages of Carcinogenesis
Initiation-
Genes are altered, mutated – spontaneously; or induced by carcinogenic agents. Ex. Radiation, pollution, smoke, heated plastics
Promotion : This lengthy but reversible process.
Pre-neoplastic cells are actively proliferating. Early screening can reverse the cancer
Progression
Between pre-malignant lesions and the actual cancer cells
This is the final stage (?) of neoplastic transformation of the cell
There is rapid increase in the size of the tumor
These cells may further undergo mutation- > may invade other organs.
Metastasis
• Cancer cells invade, penetrate and destroy surrounding tissues.
Explain the T in the TNM system
Tx- tumor cannot be assessed
T0- no evidence of primary tumor
Tis- Carcinoma in situ (in the sight)
T 1-3- progressive increase in tumor size or involvement
Explain the N in the TNM system
Lymph node involvement
Nx; cannot be assessed
N0; no node involvement
N1-N3; the higher the number the worse it gets
Explain the M in the TNM system
Metastasis
Mx; cannot be assessed
M0; no metastasis
M1 distant metastasis
Grading Vs Staging
what type of cells are involved?
Grading
Cancer cell, cell, or according new growth. Graded 1-3.
Grade1: well differentiated benign
Grade2: wells moderately differentiated not sure if its benign or Malignant needs further testing, biopsy
Grade3: Cells are poorly differentiated malignant
Staging
Classifies tumor cells, to size, invasiveness, & spreading. Uses TNM
What is cell differentiation ?
The extent of which the cell resembles the parent cell
What are the 2 major classes of cancer genes?
Tumor suppressor gene
To restrain cell growth
Can become defective- > unable to restrain the growth of cells
Oncogenes
Proto-oncogene (regulates cell division) = gene that stimulates cell’s movement through the cell cycle;
If proto-oncogene is mutated- > Oncogene(cancer)
What is the main purpose of proto-oncogenes
regulate cell division
Why do cancer cells secrete VEGF
vascular endothelial growth factor
VEGF develops blood vessels
more blood vessels= more nutrients to cancer cells compared to normal cells, this also starves the normal cells
Explain Para Neoplastic Syndrome
Symptom complexes related to cancer’s presence and action on the body
Unexpected disorder provoked by cancer cells.
Ex. lung cancer- > can cause increased production of anti-diuretic hormone leads to fluid retention
Ex. Breast cancer can lead to hypercalcemia in the blood
Give Key details about lung Cancer
• Leading cause of cancer-related death in both men and women
throughout the world • In the US, lung Ca causes more death than colorectal breast and
prostate Ca combined. • Etiology/Risk Factors:
• Cigarette smoking • Asbestos exposure • Family history • Radon exposure; arsenic exposure, history of radiation to chest area
what is Cachexia?
Progressive loss of body fat and lean body, loss of appetite
Cytokines are released by WBC to fight tumors
What is the pathophysiology of carcinogens ?
slowly “paralyze” the cilia of respiratory tract epithelium —-> further accumulation of carcinogens/toxins
Cilia helps coughing to release toxins/ its hairy and sweeps away toxins
• In Response -> cells undergo structural and genetic changes ->
hyperplasia -> metaplasia
Activation of oncogenes, and
Deactivation of tumor suppressor genes ->
Result: unchecked cell growth and proliferation ->
Hemotypsis (coughing blood)
mass grows leads to dyspnea & chest pain. Extends to plueral surface so lungs cant expand
hypoxia = low O2
Common site of metastasis
Bone and brain
Cell Mutation occurrence
Can be inherited from parents
Can occur sporadically (environmental)
What are nucleotides made of?
Sugar molecules
Phosphate
Nitrogen base
These thread like structure contain nucleic acid.,
What information does it have?
Chromosomes
Genetic info in the form of a gene
How many pairs of chromosomes are there?
How many are related to body traits?
How many are related gender?
23
22
1
What are alleles ?
Contains genes and are:
Heterozygous: Different codes, carrier of trait, visible
Homozygous
X and Y
Dominant Vs Recessive
Genotype Vs Phenotype
Dominant: Visible in heterozygous
Recessive: not manifest in the presence of Dominant trait.
Genotype: Both hetero and homo genetic make up
Phenotype: how the genetic trait is show in the person
Hair, eyes, height,
What is a carrier?
give an example
A person who is hetero for recessive trait
sickle cell, most diseases, hemophilia
Explain sex linked inheritance and what is the dominant Allele?
When a particular trait is associated with the X chromosome (gender chromosome)
Dominant allele is X
Explain Familial Cholesterolemia (FH)
What happens if not treated?
Tx
Normally: Hepatocytes take LDL- > suppresses liver synthesis of cholesterol (think of
negative feedback!) • Lack of/ or dysfunctional receptors: LDL not taken by hepatocytes- > body still thinks it
needs synthesis of cholesterol- > hepatic synthesis of LDL not suppressed- > further
cholesterol production despite high level of circulating cholesterol
This happens during food consumption
Atherosclerosis if not treated: plaque and fat build up in the arterial walls
Diet, exercise, cholesterol lowering drugs
Explain the Defect in cystic fibrosis transmembrane conductance regulator (CFTR) gene
Which organ and system is affected?
CFTR- regulates the flow of ions across the surface of epithelial cells. Water isn’t being secreted leading to thick and sluggish secretions
pancreas; respiratory system
In CF how is the Organ defected?
Pancreas: thick mucus- > plugs pancreatic ducts-> prevents pancreatic enzymes from reaching the small intestines
The enzyme plays an important role in absorbing carbohydrates , fats, and proteins. In CF the nutrients cant be absorbed
In CF how is the system affected?
Pulmonary: thick mucus- > blocks (partially/fully) the airway- > high susceptibility to respiratory infection.
Mucus stays in the lungs, leads to pneumonia
How does hemophilia affect females vs males
XXh- female is the carrier but no disease
XhY- male has the disease
