Neoplasia 2 Flashcards
Large % of cancer incidence in both male and female
Male
- prostate 20%
- colon and rectum 9%
- lung, bronchus 13%
Female
- breast 30%
- colon and rectum 7%
- lung, bronchus 13%
Estimated cancer deaths by male and female
Male
- lung, bronchus 24%
- prostate 10%
Female
- lung, bronchus 23%
- breast 15%
Environmental factors of cancer
Infectious agents
Smoking
Alcohol consumption
Diet
Obesity
Reproductive history
Environmental carcinogens
Age
Human papillomavirus or HPV affects in what part of the body
Cervical and headand neck cancers
90% cause of lung cancer
Smoking
In what part of the body can you get cancer in alcohol consumption
Carcinoma of the oropharynx, larynx and esophagus
Alcoholic cirrhosis -> ?
Hepatocellular carcinoma
Environmental factors of diet
Colorectal carcinoma
Prostate carcinoma
Breast carcinoma
an environmental factor in which14% of cancer deaths in men and 20% in women
Obesity (environmetal factors)
Prolonged estrogen exposure can lead to?
Breast carcinoma
Endometrial carcinoma
Most carcinomas occur in adults older than?
55 years of age
Age in leading cause of death in cancer in male and female
Female - ages 40-79 yrs old
Male - ages 60-79 years old
Pedriatic cancers are more likely to be cause by
Inherited mutations
Acquired predisposing conditions
- Chronic inflammation
- Precursor lesions
- Immunodeficiency states
Chronic inflammations mostly are?
Carcinomas
Localized morphologic changes that identify a field of epithelium that is at increased risk for malignant transformatio
Precursor lesions
Type of precursor lesion
Endometial hyperplasia -> endometrial carcinoma
Hyperplasia
type of precursor lesion
Barret esophagus -> adenocarcinoma
Metaplasia
Type of precursor lesio
Villous adenoma -> adenocarcinoma
CIN III - > cervical carcinoma
Dysplasia
Increased risk for cancer caused by oncogenic viruses
Those with deficits in T-cell immunity
Immunodeficiency states
A cancer that can be inherited
E.g germline mutation in tumor suppressor gene
Genetic predisposition
Types of carcinogenesis
Chemical
Radiation
Microbial
2 step of chemical carcinogenesis
Initiation
Promoter
Results from exposure of cells to a suffecient dose of carcinogenic agent
Causes permanent DNA damage
Initiation
Can induce tumor to arise from initiated cells
Not tumorigenic by themselves
Promoter
The major chemical carcinogens
Direct acting carcinogens
Indirect acting carcinogems
A major chemical carcinogens that does not require metabolic conversion to become carcinogenic
E.g alkylating agents used for chemotherapy
Direct acting carcinogens
A major chemical carcinogens that require metabolic conversion to become active carcinogens
Indirect acting carcinogens
Examples of radiation carcinogenesis
Uv rays and ionizing radiation
Carcinogenic because its ability to cause pyrimidine dimers to form in DNA
Responsible for the induction of cutaneous cancers
Ultraviolet rays UVB light
Uv spectrum of UVC UVB and UVA
UVC - stratosphere
UVB - skin surface
UVA - epidermis
Examples of UVB light cutaneous cancers
Squamous cell carcinoma
Basal cell carcinoma
Melanoma
Radiation induced cancers
Myeloid leukemia
Thyroid cancer
Breast, lung and salivary gland carcinoma
Organs which are resistant to radiation induced cancers
Skin bone GI tract
Microbial carcinogenesis: VIRUSES
HTLV-1
HPV
EBV
Hepatitis B and C
Associated malignancy
Adult T-cell leukemia
HTLV-1 virus
associated malignancy
Squamous cell carcinomas of the cervix, anogenital region , and heal and neck
HPV
Associated malignancy
Burkitt lymphoma, nasopharyngeal carcinoma
EBV
Associated malignancy
Hepatocellular carcinoma
Hepatitis B and C
Microbial carcinogenesis: bacteria
Helicobacter pylori
asociatd malignancy
Gastric adenocarcinoma MALToma
Helicobacter pylori
How is cancer developed?
- Proto-oncogenesis: where normal cellular genes promote cell proliferation
- Cancer promoting agents
- Oncogenes: mutated or over expressed version of proto-oncogenes that function autonomously, having lose dependence on normal growth promoting signals
- Cancerous cell na
Principal targets of cancer causing mutations
- Growth promoting proto-oncogene
( gain of function ) - Growth inhibiting tumor sppressor genes
( loss of unction ) - Genes that regulate apoptosis
( suppress apoptosis -> gain of function, promote apoptosis -> loss of function ) - Genes for DNA repair
( loss of function )
Guardian of the genome
P53
what is P53?
A tumor suppressor gene altered in the majority of cancers
P53 causes cell cyclearrest by upregulating the __ inhibitor
CDK inhibitor p21
Tumor uppressor gene directly or indirectly inactivated in most human cancers
RB, governor of the cell cycle
In what state is RB (retinoblastoma protein) active?
Active in its hypophosphotrylated state preventing G1/S transition
Gatekeeper of colonic neoplasia
APC - adenomatous polyposis coli
Encodes a factor that negatively regulates the WNT pathway in colonic epithelium by promoting the formation of a complex that degrades ___??
B-catenin
How is cancer developed?
Initiating mutation
Acquisiiton of cancer hallmarks
Further genetic evolution
The first driver mutation
Initating mutation
Contribute to te acquisition of cancer hallmarks
Driver mutation
Mutations that lead to genomic instability
Passenger mutation
No phenotypic consequence
More common than driver mutations
Passenger mutation
Hallmarks of cancer
Avoiding immune destruction
Sustaining proliferative signaling
Deregulating cellular energetics
Inducing angiogenesis
Resisting cell death
Genetic instability
Activating invasion and metastasis
Tumor promoting inflammation
Enabling replicative immortality
Evading growth suppressors
Associated malignancy
Burkitt lymphoma, nasopharyngeal carcinoma
EBV
First driver mutation
Initiating mutation
What agent.
By product of metal smelting
Lung carcinoma, skin carcinoma
Arsenic and arsenic compounds
Typical use of the agent :
For brake linings, floor tiles
Asbestos
Widely used as solvent and fumigant
Can cause acute myeloid leukemia
Benzene
What agent
Yellow pigment and phosphors, used as batteries and as allow in metal platings and coating
Can cause prostate carcinoma
Cadmium and cadmium compounds
Typical use of nickel compound
Can cause lung and oropharyngeal carcinoma
By product of stainless steel arc welding
What agent:
Vinyl polymers, adhesive for plastics
Causes hepatic angiosarcoma
Vinyl chloride
Tumor suppressor gene altered in the colonic neoplasms
APC
