Exam 2- Cancer Epidemiology Flashcards
Cigarette smoking
smoking increases DNA methylation. Cigarette smoking is carcinogenic and remains the most important cause of cancer. Tobacco accounts for nearly one in five deaths, yet it is the single most preventable cause of death and disease in the United States. The risk is greatest in those who begin to smoke when young and continue throughout life. Besides lung cancer, tobacco use increases the risk for cancers of the mouth, lips, nasal cavity and sinuses, larynx, pharynx, esophagus, stomach, pancreas, kidney, bladder, uterus, cervix, colorectum, and ovaries as well as acute leukemia.
Second-hand smoke
the combination of sidestream smoke (burning end of a cigarette, cigar, or pipe) and mainstream smoke (smoke exhaled by the smoker). More than 4000 chemicals have been identified in mainstream tobacco smoke (250 chemicals as toxic), 55 of which 60 are considered carcinogenic. Nonsmokers who live with smokers are at greatest risk for lung cancer
Obesity
Evidence is evolving of the association between obesity and cancers of the thyroid, gallbladder, liver, and ovary as well as aggressive types of prostate cancer and non-Hodgkin lymphoma. Importantly, obesity is recognized as a poor prognostic factor for several cancers. Worrisome are the effects of obesity on incidence and the poor outcomes in individuals with cancer because of the rising obesity epidemic.
Chronic inflammation
Cancer development in the presence of chronic inflammation involves the continuous presence of cytokines, chemokines, reactive oxygen species (ROS), oncogenes, cyclooxgenase-2 (COX-2), 5-lipoxygenase (5-LOX), and matrix metalloproteinases(MMPs) aswell asthe activation of essential transcription factors, such as nuclear factor κB (NF-κB).
Reverse Warburg Effect
cancer cells can use oxidative stress as a “weapon” to extract recycled nutrients from cancer-associated fibroblasts in the stromal tissue. The oxidative stress changes the normal fibroblast cancer-associated fibroblasts (CAFs). This transition seems to cause the aging of the stromal environment, or senescence. Autophagic senescent fibroblasts then produce high-energy nutrients resulting in anabolic tumor growth. This two-compartment tumor metabolism is sometimes called the Reverse Warburg effect.
HPV
the most common sexually transmitted virus in the United States. At least 50% of sexually active people will have genital HPV at some time in their lives.HPVs are a group of more than related viruses. More than 40 of these viruses can easily spread from direct skin contact or through vaginal, rectal, or oral sex. Low-risk HPVs do not cause cancer but can cause skin warts, called condylomata acuminata. High-risk, or oncogenic, HPVs can cause cancer. Even though about a dozen HPVs are identified, HPV types 16 and 18 are responsible for the majority of cancers. However, most high-risk HPV infections may cause cytologic abnormalities or abnormal cell changes that disappear unexpectedly. Persistence of infection with high-risk HPV is a prerequisite for the development of cervical intraepithelial neoplasia (CIN)
Mainstream smoke
Smoke exhaled buy a smoker
Sidestream smoke
Smoke from the burning end of a cigarette cigar or pipe
Environmental tobacco smoke
Smoke from the burning end of the cigarettes, cigars, or pipe plus the smoking exhaled by the smoker
Mel nutrition
Decreases repair of DNA
Xenobiotics
Chemicals that are not synthesized in the body but maybe found in foods
Insulin-like growth factor 1 (IGF1)
Stimulates cell division and has anti-aoptotic affects that increase the risk for several types of cancer
Hypoxic tumor cells
Less sensitive to radiation in this less likely to die by apoptosis
Anti-cancer dietary factors
Lycopene from tomatoes, polyphenols from T, organic sulfur compounds from garlic
Pro cancer dietary factors
Central obesity, malnutrition, aflaxtocin from moldy peanuts,
