BIOL 2160 Exam 2

BIOL 2160 Exam 2 - B IOL 2160 EXAM 2 Lecture 1: Cancer 2nd...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
BIOL 2160 EXAM 2 Lecture 1: Cancer 2 nd leading cause of death in the US (kills about 500,000 people/year) Causes 20% of deaths in the US each year Due to failure of cellular mechanisms that normally control cell division o Cell mechanisms that stop division are damaged This is a result of genetic damage, that is often due to tumor-promoting chemicals, hormones, and sometimes viruses Carcinogens o Environmental substances that induce cancer-causing mutations in cells o Includes: UV radiation Tobacco Alcohol Asbestos Benzene Lead Nickel Countless other chemicals… o These things damage DNA and cause mutations (switch up the order of nucleic acids) Oncogenesis o The cancer-forming process
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
o When a normal cell becomes cancerous o Result of an interplay b/t genetics and the environment o Most cancers are a result of genes being mutated by carcinogens, or by errors in the copying and repairing of DNA o Ex. Getting sunburned causes cells to divide even more and increases chances of cancer Tumor o A rapidly proliferating cell type that escapes normal growth restraints and stimulates the growth of vasculature (blood vessels) to obtain oxygen o Cells that proliferate quickly, and are in abundant supply, are the most dangerous Ex. Skin cells, ovarian cells Metastisis o A case in which cells from the primary tumor migrate to new sites where they can form secondary tumors o Complex processes, and invasion of new tissues is non-random, depending on the nature of both the metastasizing cell and the invaded tissue o Most cancer deaths are due to invasive, fast-growing metastasized tumors Proliferating Cells o In order for most mutations in oncogenes to cause cancer, they must occur in dividing cells, so that mutation is passed on o Mutations in non-dividing cells (most neurons and muscle cells) usually aren’t cancerous o Brain and muscle cancer are rare in adults Because these cells don’t divide and mutations don’t get passed on Location o Cancer frequently originates at the sites of injury or infection
Background image of page 2
o Immune cells migrate to sites of tissue damage, and release growth factors to promote healing o The extracellular matrix is reconstructed o These properties may contribute to the establishment and growth of a tumor Angiogenesis o Recruitment of new blood vessels is required for the growth of all tumors o Without blood, the average tumor mass can grow to be only 2 mm in diameter o b/c as new cells are dividing on the outside of the tumor mass, older tumor cells are dying within the tumor mass due to lack of nutrients o Without blood they will stay the same size Viruses that cause cancer o HPV- Human Papilloma Virus Causes warts on the skin, mouth, genitals, and larynx Spread through physical contact with infected areas ¾ sexually active people have HPV Clears up naturally in 1 or 2 years in 90% of cases 80% of women will get HPV in their lifetime
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/01/2011 for the course BIOL 2160 taught by Professor Kt during the Summer '08 term at LSU.

Page1 / 23

BIOL 2160 Exam 2 - B IOL 2160 EXAM 2 Lecture 1: Cancer 2nd...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online