Intro to Cancer Flashcards
Mitosis
cell splits into 2 genetically identical daughter cells
Meiosis
- cell splits but keeps only half the genetic chromosomes (23 vs. 46)
- Only occurs in sex cells of testes and ovaries
Differentiation
normal process where cells change in order to specialize for certain body functions
Hyperplasia
increase in number or density of normal cells
Metaplasia
Change in the normal pattern of cell differentiation (cells aint where they are supposed to be)
Dysplasia
cells differentiate in abnormal ways
Anaplasia
Immature or undifferentiated cell reproduction
What is cancer?
- classification of many diseases
- can affect many different types of cells or body systems
- can affect anyone though there are risk factors
- marked by uncontrolled growth and spread of abnormal cells
Tumor
aka neoplasm
- can be either benign or malignant
- mass of new tissue which grows independently from surrounding tissues and has no function
- cells grow at rates which are uncoordinated
- share properties of parents but altered shape/size
- provide no benefit and may be harmful
- still require blood, oxygen, nutrients
Benign tumors
- localized growths
- solid, well defined borders
- stop growing when they reach the border of other tissues (inhibition)
- grow slowly and remain stable in size
- usually easily removed and don’t recur
- can still cause problems (crowding, obstructions, etc..)
Malignant tumors
- primarily what we think of when we refer to cancer
- grow aggressively
- irregular in shape, no defined borders
- cut through other tissues causing injury
- varying degrees of differentiation from parent cells
- altered cell structure
- simple metabolic activity, only care about mitosis
- progressive mutations leads to greater deviation and sometimes immortality
- promotes own survival, create vascular and support structures for own use
NO INHIBITION
Transplantability
- able to break away and grow elsewhere
- associated with malignant tumors
Angiogensis
- formation of new blood vessels from old
- normal body function
- integral in wound healing
- formation of granulation tissue (connective tissue)
- key step that separates benign from malignant tumors
“in situ”
pre-cancer
Invasion
-as cancer cells grow they invade surrounding tissue
- cause pressure atrophy
- degrade barriers between tissues
- cancer cells easily separate
- chemotaxis
Chemotaxis
cells breakdown drawing phagocytes to clean up; this attracts cancer cells too
-as body starts to attack cancer, actually release some cellular mediators, spurs growth of more cells
Metastasis
process where cancer cells spread from their primary site to distant organs and tissues
- As malignant cells spread they access vascular and lymphatic systems (even possibly creating their own) allowing for spread to distant parts of the body
- The majority of cancers have already metastasized by the time they are discovered or diagnosed
Etiology
- several theories to origins of cancer
- 2 primary factors central to all: Carcinogens and immune impairment
Carcinogens
substances which can cause genetic mutation in cells through exposure
- external (chemicals, substances, viruses, etc.)
- internal (inherited mutations, hormones, etc.)
- everyone is exposed to these on some level and at some point
- other factors like genetics, immune response, exposure to viruses, etc. all contribute to carcinogenises
immune impairment
lessens bodies’ ability to fight and control abnormal cell growth
General Risk factors
- heredity
- age
- gender
- poverty
- stress
- diet
- occupation
- infections
- tobacco
- alcohol
- recreational drug use
- obesity
- sun exposure
Initiation
- cancer cells arise from “normal” cells due to a change in the cells’ genetic structure
- mutation occurs in the cells’ DNA
- These mutations can be inherited via a generic link fro parents or acquired during life due to exposure to carcinogens
