Cell Physiology Flashcards
What is melanoma?
Cancer developed by mutations in the melanocytes, highly metastatic and resistant to treatments. Very common in the fair-skinned population, because most are caused by sun exposure.
What are the major clinical subtypes of melanoma?
Melanoma in situ Superficial spreading melanoma Lentigo maligna Nodular melanoma Acral lentiginous melanoma
What are the key physiological processes for human health?
Hepatic/Renal
Nutrient metabolism
Circulatory system
Nervous system
Why is hepatic and renal function important?
It deals with the hydration, detoxification, and elimination of metabolic waste products
Why is nutrient metabolism important?
Catabolism and anabolism are important to maintain energy
Why is circulatory function important?
The bloodstream carries many important nutrients throughout the body, especially oxygen to the tissues
Why is nervous system function important?
The sympathetic, parasympathetic, and autonomic nervous systems are important for fight/flight responses and maintaining normal organ function
Melanoma in situ
Most common type, typically does not metastasize, can occur at any age
Superficial spreading melanoma
Most common malignant type, more prevalent in younger populations
Lentigo maligna
Older adults, correlated with chronic sun exposure
Nodular melanoma
Usually in older adults, correlated with chronic sun exposure, invasive from the start, very dangerous and high rate of mortality
Acral lentiginous melanoma
Very rare but most common in Asians and Blacks, occurs on acral skin, not correlated with sun exposure
Earliest stages of human development
Fertilized egg, 2 cell stage, 4 cell stage, 8 cell stage, morula, blastula, early gastrula, gastrula
Types of stem cells
Totipotent, pluripotent, multipotent, unipotent, induced pluripotent
Totipotent Stem Cells
Give rise to all cells in the body and an entire human being
Zygote is the only truly totipotent, morula can be argued to be
Pluripotent
Give rise to all cells of the body but not an entire human being
Cells of the inner mass of early blastocyst
Multipotent
Give rise to limited range of cell types
Adult stem cells found in many tissues
Unipotent
Give rise to only one cell type
Most adult stem cells
Induced pluripotent
Differentiated cells that are transferred with genes encoding specific transcription factors - makes the cell pluripotent
Two lineages of stem cells
Either go to make more stem cells or differentiate into specialized cells
Symmetrical vs Asymmetrical Division
Symmetrical - stem cell makes 2 more stem cells to increase numbers
Asymmetrical - stem cell makes 1 stem cell and 1 cell to differentiate
Adult stem cells
In most organs, they are not completely pluripotent, usually are unipotent and function in homeostatic maintenance
Niches
Regions of tissues in which adult stem cells reside
The malignant transformation
Gene mutations, failure of DNA damage repair mechanisms, multiple changes in gene expression and metabolism, loss of tumor cell adhesion, metastasis to other organs
What makes a tumor cell malignant?
It can metastasize to other parts of the body
What happens to a tumor cell that causes it to metastasize?
Adhesion properties are disrupted and the ECM is broken down
What can tumor cells do to ensure survival?
Send chemical signals to attract blood vessels, alter their metabolism to survive in certain situations
What is the idea of “multiple hit” mutations in cancer?
That it is a series of mutations that causes the growth of a tumor, because the first one is generally recessive, but a second hit to that cell can lead to a decrease in DNA caretaker cells and increase the likelihood of further mutations
