Exam 1 Flashcards
What are the two components of tumors
Neoplasticism cells that constitute the parenchyma and reactive stroma made up of connective tissue, bv, and cells of the immune system; *growth and spread dependent on stroma
What is a desmoplasia
Neoplasm where the parenchyma cells stimulate formation of collagenous stroma; *ie: cancers of the breast; can make them stony hard, referrered to as scirrhous
What are adenomas
Benign epithelial neoplasms arising from glands
What are papillomas
Benign epithelial neoplasms producing finger like or warty projections
What is a polyp
When a neoplasms produces a visible projection above a mucosal surface (if in glandular tissue, called adenomatous polyp)
What are sarcomas
Malignant tumors arising in solid mesenchymal tissues (fibrosarcoma, chondrosarcoma, leiomyosarcoma, rhabdomyosarcoma)
What are carcinomas
Malignant neoplasms of epithelial cell origin (derived from germ layers)
What is an example of a mixed tumor
Mixed tumor of salivary gland; contains epithelial components scattered with a myxoid stroma that may contain cartilage or bone; all arise from a single clone capable of producing both epithelial and myoepithlial cells *called pleomorphic adenoma
What is a dermoid cyst
Ovarian cystic teratoma
What are hamartomas
Disorganized benign masses composed of cells indigenous to involved site
What is a choristoma
Heterotropic rest of cells; ie: well developed and normally organizers pancreatic tissue in submucosa of stomach
What are the tumors of mesenchymal origin
Benign: fibromyalgia, lipoma, chondroma, osteoma
Malignant: Fibrosarcoma, Liposarcoma, Chondrosarcoma, osteogenic sarcoma
What are the tumors of vessels and surface coverings
Benign: hemangioma, lymphangioma, benign fibrous tumor (from mesothelium), meningioma
Malignant: angiosarcoma, lymphangiosarcoma, mesothelioma, invasive meningioma
What are the tumors from blood cells and related cells
Only malignant types: leukemia and lymphoma
What are the tumors of muscle origin
benign: Leiomyoma (smooth m) and rhabdomyoma (striated)
Malignant: leiomyosarcoma, rhabdomyosarcoma
What are the tumors of epithelial origin
Benign: squamous cell papilloma (strat squamous), adenoma, papilloma, cystadenoma, bronchial adenoma, renal tubular adenoma, hepatic adenoma, transitional cell papilloma (urinary tract), hydatidiform mole, Nevus (melanocytes)
Malignant: squamous cell carcinoma; basal cells carcinoma (basal cells of skin or adnexa), adenocarcinoma, papillary carcinomas, cystadenocarcinoma, bronchogenic carcinoma, renal cell carcinoma, hepatocellular carcinoma, transitional cell carcinoma, seminoma and embryonal carcinoma (germ cells), malignant melanoma
What are the mixed tumors
Benign: pleomorphic adenoma
Malignant: malignant mixed tumor of salivary origin, Wilms tumor (renal anlage)
***derived from ONE germ layer
What are the teratogenous tumors
Benign: mature teratoma, dermoid cyst
Malignant: Immature teratoma, teratocarcinoma
*** derived from more than one germ layer
What is anaplasia
Lack of differentiation of tumor; considered hallmark of malignancy
Are benign or malignant tumors well differentiated
Benign; malignant exhibit wide range of differentiation and most exhibit alternations that betray their malignant nature
What other morphological changes is often associated with anaplasia
- pleomorphism: variation in size and shape (tumor giant cells)
- abnormal nuclear morphology: nuclei are disproportionately large w/ nuclear:cytoplasm ratio of 1:1; nuclear shape irregular and coarsely clumped (hyperchromatic)
- mitoses: many cells in mitosis (atypical, bizarre mitotic figures)
- loss of polarity: grow in disorganized fashion
- can develop large areas of ischemic necrosis because require large vascular supply
What is carcinoma in situ
Dysplastic changes that involve the full thickness of the epithelium but does not penetrate basement membrane; once it breaches, is referred to as invasive
What forms the capsule in benign tumors
ECM deposits stimulated by hypoxic damage resulting from pressure of expanding tumors; does not limit growth of tumor, but rather creates. The tumor to be discrete, readily palpable, moveable and easily excusable: exception - hemangiomas -> may not be able to be respected because unencapsulated and permeate the site in which they arises
What are examples of malignancies that do not often metastasize
Gliomas and basal cell carcinomas; invade but do not met
How can cancers spread
- direct seeding of body cavities or surfaces: most often in peritoneal cavity; particularly characteristic of ovaries (can fill cavity with pseudomyxoma peritonei: gelatinous neoplastic mass)
- lymphatic spread: most common for carcinomas but sarcomas can also use this route; sentinel LN = first node in regional lymphatic basin that receives lymph flow from primary tumor;
- hematogenous spread: typical of sarcomas, but also seen with carcinomas; veins more easily penetrated; liver and lungs most frequently involved; vertebral Mets associated with carcinomas of prostate and thyroid
What cancers have a propensity for invading veins
Renal cell carcinoma: renal vein -> IVC sometimes to right side of heart
Hepatocellular carcinomas: portal and hepatic radicles
Where does breast carcinoma spread
Bones
Where does bronchogenic carcinoma typically spread
Brain and adrenals
Where does neuroblastoma typically spread
Liver and bones
What are the most common tumors in men
Prostate, lung and colon/rectum
What are the most cancers in females
Breast, lung, and colon/rectum
What cancer causes the most deaths in women
Lung
What tumors are Hispanics at risk for
Stomach, liver, uterine cervix, and gallbladder, and certain leukemia’s
What cancers does alcohol consumption put people at risk for
Carcinomas of oropharynx (except lip), larynx, esophagus, and hepatocellular carcinoma
Which cancers are thought to be linked to diet
Prostate, breast, and colorectal carcinomas
Are carcinomas typically seen in children
No - extremely rare
What are the common cancers seen in children
Small round blue cell tumors: neuroblastoma, wilms tumor, retinoblastoma, acute leukemia’s, and rhabdomyosarcomas
What are the acquired predisposing conditions of cancer
Chronic inflammations, precursor lesions, immunodeficiency states
Tumors arising in the setting of acute inflammations are usually _________
Carcinomas
What are the chemicals involved in “occupational cancers” and what cancers do they cause
Arsenic: lung and skin carcinoma Asbestos: Lung, esophageal, gastric, colon carcinoma, mesothelioma Benzene: AML Beryllium: lung carcinoma Cadmium: prostate carcinoma Chromium: Lung carcinoma Nickel: lung and oropharyngeal carcinoma Radon: lung carcinoma Vinyl chloride: hepatic angiosarcoma
What are the chronic inflammatory states that lead to cancer
Asbestosis/silicosis: mesothelioma, lung carcinoma
IBD: colorectal carcinoma
Lichen sclerosis: Vulvar squamous cell carcinoma
Pancreatitis: pancreatic carcinoma
Chronic cholecystitis: GB cancer
Reflux esophagitis: esophageal carcinoma
Sjogren, hashimoto: MALT lymphoma
Gastritis/ulcers: cholangiocarcinoma/ colon carcinoma
Hepatitis: hepatocellular carcinoma
Osteomyelitis: carcinoma in draining sinuses
Chronic cystitis: bladder carcinoma
What are examples of precursor lesions
Inflammatory precursor lesions: Barrets esophagus, bronchial squamous metaplasia, colonic metaplasia of stomach (pernicious anemia nad chronic atrophic gastritis)
Non-inflammatory: endometrial hyperplasia, leukoplakia (thickening of squamous epithelium in oral cavity or penis/vulva -> squamous carcinoma)
Benign neoplasms: colonic follows adenoma
What are the steps involved in carcinogenesis
- initiation: exposure to carcinogenic agent; alters cell making it potentially capable of giving rise to a tumor; *initiation alone NOT significant for tumor formation
- initiation causes permanent DNA damage; rapid and irreversible and has memory; tumors are produced even if promoting agent is delayed for several months
- promoters induce tumors to arise from initiated cells, but they are nontumorigenic by themselves; promoter affects are reversible
What are all initiating chemical carcinogens
Highly reactive electrophiles that react with nucleophilic sites in the cell
What are direct acting carcinogens
Do not require conversion to become carcinogenic; chemotherapeutic drugs are example
What is an ultimate carcinogen
Product of metabolism of indirect acting carcinogen; *tobacco
What are polymorphisms of CYP1A1 linked to
Lung cancer; variations in P-450 gene help determine susceptibility to cancer due to indirect carcinogens
What are “hotspots”
Spots in the genome with specific DNA sequences that carcinogens target; ie: aflatoxin B (produced by aspergillosis) -> associated with hepatocellular carcinoma causes G:C ->T:A transversion in codon 249
What are promotors of chemical carcinogenesis
Chemical agents that are not mutagenic but instead stimulate cell proliferation
What is the difference between melanoma and nonmelanoma skin cancers
Nonmelanoma: associated with total UV exposure
Melanoma: associated with intense intermittent exposure (sunbathing)
Which UV ray is responsible for causing cutaneous cancers
UVB (280-320_
What is the most common cancer caused by radiation
Myeloid leukemia’s, then cancer of the thyroid (but only in the young)
Which retrovirus is implicated in cancer of humans
Human T cell leukemia virus type I; causes adult T cell leukemia/lymphoma; T cells major target of virus; requires trasmission via bodily fluid; high fraction of tumors express FOXP3 -> opportunistic infections often cause of death; HTVL does not contain an oncogene and does not integrate next to a proto oncogene
What special gene does HTVL-1 contain
Tax: essential for viral replication, and alters transcription of host cell genes
*impt for development of cancer hallmarks -> increased pro-growth signaling and cell survival (stimulates AKT and NFkB and upregulates cyclin D2); increased genomic instability: interferes with DNA-repair functions and inhibits cell cycle checkpoints
What are the oncogenic DNA viruses
HPV, EBV, Hep B, Merkel cell polyoma, kaposi sarcoma herpesvirus
What are the high risk HPV strains
16 and 18 -> integrated into genome; interrupts viral DNA within E1/E2 open reading farm, leading to loss of E2 viral repressive and overexpression of E6 and E7 which are oncoproteins
What does E6 do
Binds to and mediated degredation of p53 and stimulates expression of TERT whic his a subunit of telomerase ; *p53 Arg72 is much more likely to develop cervical carcinomas
What does E7 do
Binds RB and displaces the E2F, promoting progression through cell cycle; also inactivates CDK inhibitors p21 and 27; also activate cyclins E and A
What is needed for carcinogenesis of HPV
Need to be co-transferred with a mutated RAS gene
What are the proteins that act as oncogenes in EBV
- LMP-1: behaves Iike active CD40 receptor, activates NFkB and JAK.STAT t hat promote B cell survival and proliferation; prevents apoptosis by activating BCL2
- EBNA-2: mimic active notch receptor; activates cyclin D and SRC family of protooncogenes
- vIL-10: prevents macrophages from activating T cells
Do burkitt lymphoma cells express LMP-1, EBNA-2?
No
Which translocation is involved in burkitt lymphom
8:14 (MYC)
Is EBV directly oncogenic in Burkitt Lymphoma
No; sets stage for acquisition of 8:14 translocation
What is different about B cell lymphomas in immunosuppressed individuals in comparison to Burkitt lymphoma
They express LMP-1 and EBNA2; also usually lack MYC translocations
What is nasopharyngeal carcinoma associated with
EBV infection; develop IgA abs before tumor; LMP-1 expressed and activated NFkB (upregulates VEGF, FGF-2, MMP9 and COX2)
Do HBV or HCV encode any viral oncoproteins
No; mechanism for HBV thought to be virus causing damage and constant repair leading to genomic damage
What is H pylori associated with
Gastric adenocarcinomas and gastric lymphomas
How does H pylori cause gastric adenocarcinoma
Causes increased epithelial proliferation in setting of chronic inflammation
What do h pylori strains associated with gastric adenocarcinoma contain
Cytotoxin associated A (CagA); penetrates into gastric epithelial cells
How are gastric lymphomas cured
Antibiotic therapy to h pylori (removes stimulation of T cells); causes MALT lymphomas -> B cell lymphomas
What is cancer cachexia associated with
Equal loss of fat and lean m, elevated basal metabolic rate, systemic inflammation (increased acute phase proteins)
What are paraneoplastic syndrome
Cancer-bearing individuals who develop signs and symptoms not explained by the anatomic distribution of their cancer
Why are paraneoplastic syndromes important to recognize
Can be earliest manifestation of neoplasm, can cause significant clinical problems, can mimic metastatic disease and confound treatment
What is an endocrinopathy
Ie: Cushing syndrome; common in persons with carcinoma of the lung (small cell) -> have elevated serum pro-opiomelanocortin and corticotropin (former is not found in serum of patients with excess corticotropin produced by pituitary)
What is the most common paraneoplastic syndrome
Hypercalcemia; causes osteoclasts and production of calcemic humoral substances by extraosseous neoplasms (only later is paraneoplastic)
What humoral factors are associated with paraneoplastic hypercalcemia of malignancy
Parathyroid hormone related protein: resembles PTH and share a GPCR; produced in small amounts by keratinocytes, m, bone, and ovary; regulates calcium transport into a rating breast and across placenta; *most associated with CA of breast, lung (squamous cell carcinoma), kidney, and ovary
-IL-1, TGF alpha, TNF, dihydroxyvitamin D also play a role
What is acanthosis nigricans
Gray-black patches of thickened hyperkeratotic skin with a velvety appearance; in ppl over 40, associated with cancer; associated with gastric, lung, and uterine carcinoma
What is hypertrophic osteoarthropathy
Associated with lung carcinoma; characterized by periosteal. New bone formation (distal ends of long bones, metatarsals/carpals, and prox phalanges), arthritis of adjacent joints and clubbing of digits
What cancers are Trousseau syndrome most often associated with
Lung and pancreas
What cancer is DIC most commonly associated with
Acute promyelocytic eukemia and prostatic adenocarcinoma
What are nonbacterial thrombotic endocarditis
Nonbacterial fibrinous vegetations on cardiac valve (more on left) found in individuals with mucin secreting adenocarcinomas
What is grading of tumors dependent on
Degree of differentiation of tumor cells and sometimes the number of mitoses or architectural features
What is staging of cancer dependent on
Size of primary lesion, extent of its spread to regional LN, and presence or absence of blood born Mets; uses TNM system; primary lesion T1-T4 based on increasing size (T0 is in situ), N0-N3 for involvement of LN in increasing number and range, and MO-M2 indicating presence of Mets and number
What kinds of cancers are cytologic smears most usefu for
Endometrial carcinoma, lung carcinoma, bladder and prostatic tumor, gastric carcinomas
What are the limits of cytology and histology in cancer diagnosis
Hard to determine tumor type especially of poorly differentiated tumors
What is immunohistochemistry used to do
- categorize undifferentiated malignant tumors: use abs to intermediate filaments - cytokeratins for epithelial (carcinoma), desmin for m
- determines site of origin of met tumors: ie: PSA and thyroglobulin
- Detects molecules that have prognostic or therapeutic significance: ie: hormone receptors in tumors (better breast CA prognosis); can also stain for products of oncogene (HER2 -> poor prognosis)
What is flow cytometry used for
To identify antigens expressed by blood forming tissues (B and T cell lymphomas and leukemia’s, and myeloid neoplasms); *multiple antigens can be assessed simultaneously
What is used to determine polyclonal versus monoclonal proliferation’s
PCR
What is the translocation seen in Ewing sarcoma
11;22 q24;q12
What cancer has the PML-RARA fusion gene
Acute promyelocytic leukemia
What cancer is associated with BRAF mutation
Melanoma, hairy cell leukemia’s, colon cancers, papillary thyroid carcinoma, langerhans cell histiocytes is
What hormones are used as tumor markers and for which cancers
- hCG: trophoblastic or nonseminomatous testicular tumors
- calcitonin: medullary carcinoma of thyroid
- catecholamine: pheochromocytoma
What are the incidental antigens used as tumor markers
- alpha fetoprotein: liver cell cancer, nonseminomatous germ cell tumors of testis
- carcinoembryonic antigen: carcinomas of the colon, pancreas, lung, stomach, and heart
What isoenzymes are used as tumor markers
- prostatic acid phosphatase: prostate cancer
- neuron specific enolase: small cell cancer of lung, neuroblastoma
What are immunoglobulins used as a marker for
Multiple myeloma
What mucin are used as tumor markers
- CA-125: ovarian cancer
- CA-19-9: colon cancer, pancreatic cancer
- CA-15-3: breast cancer
What cell free DNA markers are used as tumor markers
- TP53, APC, RAS mutants in stool and serum: colon cancer
- TP53, RAS mutants in stool and serum: pancreatic cancer
- TP53, RAS mutants in sputum and serum: lung cancer
- TP53 mutants in urine: bladder cancer
PSA test has ______ specificity and _______ sensitivity
Low; low
What is DALY
Disability adjusted life year: sums of years of life lost due to premature mortality and the years of life lost to disability in a population
What is the life expectancy free of disability for women and men
Men: 58.3
Women: 61.8
What is the single leading global cause of health loss
Undernutrition
What is the leading cause of death in developed countries
Ischemic heart disease and CV disease; risks are smoking, high BP, obesity, high cholesterol and alcohol abuse
In developing countries, half of the leading causes of deaths are ________
Infections diseases
What are half of the deaths in children younger than 5 attributed to
Pneumonia, diarrheal diseases, and malaria
What are the categories of emerging infectious diseases
- diseases caused by newly evolved strains or organisms
- diseases caused by pathogens endemic in other species that jumped to human populations *HIV
- diseases caused by pathogens that have been present in human populations but show a recent increase in incidence (dengue fever)
What are xenobiotics
Exogenous chemicals in air, water, food, and soil that may be absorbed via inhalation, ingestion, or skin contact; almost always lipophilic and metabolized to water soluble substances or are activated to form toxic metabolites
What are the two phases of metabolization of xenobiotics
I: undergo hydrolysis, oxidation or reduction
II: products from phase I are metabolized into water soluble products via glucoronidation, sulfation, methylation and conjugation with glutathione
What is the most important catalyst of phase I Reactions
Cytochrome P 450 (in ER of liver mostly); they are heme containing enzymes
What can decrease CYP activity
Starvation or fasting
How do inducers of CYPs work
Bind to nuclear receptors which heterodimerize with retinoic X receptor to form transcriptional activation complex that associates with promoter elements of CYP gene; example of receptor is style hydrocarbon receptor, peroxisome proliferator activated receptor, constitutive androstane receptor and pregnane x receptor
What makes up smog
Sulfur dioxide, lead, carbon monoxide, ozone, nitrogen dioxide, and particulate matter
What is ground level ozone
Gas formed by reaction of nitrogen oxides and volatile organic compounds in presence of sunlight; produces free radicals which injure epithelial cells in respiratory tract and type I alveolar cells
What can sulfur dioxide cause
Burning sensation in nose and throat, difficulty breathing, and asthma attacks in susceptible individuals
What is soot involved in
Aka particulate matter; pulmonary inflammation nad secondary CV effects; fine or ultra fine particles less than 10 micrometers are most harmful -> phagocytosed -> inflammation
What is carbon monoxide
Systemic asphyxiant; nonirritating, colorless, odorless produced from incomplete oxidation of hydrocarbons (engines, furnaces, cigs); chronic poisoning can occur in ppl working underground, in tunnels, and highway toll booths
How does CO kill
CNS depression (especially in basal ganglia and lenticular nuclei) and systemic hypoxia (occurs when Hbg is 20-30% saturated with CO) unconsciousness and death likely with 60-70% saturation; diagnosis made by measuring carboxyhemoglobin levels in blood
What are the characteristics of acute CO poisoning
In light skinned individuals, present with cherry red color of skin and mucous membranes; with longer exposure, brain can become edematous with punctuate hemorrhage’s and hypoxia-induced neuronal changes
What are the indoor pollutants
Cigarette smoke, NO, CO
- wood smoke: contains oxides of N and C pollutants; irritant that can cause lung infections and contain polycyclic hydrocarbons (carcinogens)
- Bioaerosols: can cause legionnaires, viral pneumonia, or common cold, OR allergens from pet dander, dust mites, and fungi
- Radon: derived from uranium present in soil and homes can cause lung CA in miners; low level exposure not a risk
- formaldehyde: problem in refugees from environmental disasters living in poorly ventilated trailers-> carcinogen
What harmful effects can lead have
Binds to sulfhydryl groups in proteins and interferes with calcium metabolism which leads to hematologic, skeletal, neuro, GI, and renal toxicities
When is treatment for lead poisoning mandated in children
When blood lead levels exceed 45 micrograms/dL; but subclinical lead poisoning can occur below this level (includes subtle deficits in intellectual capacity, hyperactivity, and poor organizational skills)
Where is most of absorbed lead incorporated
Into bones and teeth where it competes for calcium
What feature of lead poisoning dominated in adults
Peripheral neuropathy we
Do children or adult absorb more lead
Children; the higher absorption and more permeable BBB creates high susceptibility to brain damage in children; causes inhibition of NT caused by disruption of calcium homeostasis
What levels of lead (in microg/mL) cause certain symptoms in children
10: developmental toxicity
20: decreased nerve conduction velocity
40: decreased hemoglobin synthesis
100: encephalopathy
150: death
What are the pathological features of lead poisoning in adults
Brain: headache, memory loss
Gingiva: lead line
Blood: anemia, red cell basophilic stippling
Peripheral nerves: demyelination
Kidney: chronic tubulointerstitial disease
GI: Ab pain
What are the pathological features of lead poisoning in children
Brain: encephalopathy, mental deterioration
Bones: radiodense deposits in epiphyses; inhibits healing of fractures by increasing chondrogenesis and delaying cartilage mineralization
What enzymes does lead inhibit
Aminolevulinic acid DH and ferrochelatase: both involved in heme synthesis; latter catalyze incorporation of iron into protoporphyrin; causes microcytic hypochromic anemia stemming from suppression of hemoglobin synthesis
How do you diagnose lead poisoning
Elevated Levels of lead in blood or free red cell protoporhyrin
Describe the morphology of lead poisoning
Inhibition of ferrochelatase causes appearance of ring sideroblasts, which are red cell precursors with iron laden mitochondria that are detected with Prussian blue stain; causes brain edema and demyelination and necrosis of cortical neurons accompanied by diffuse astrocytic proliferation
What are the first mm to be affected by lead poisoning in adults
Extensor mm of wrist and fingers (causes wrist drop) followed by perineal mm causing foot drop
What are the harmful effects of mercury
Binds to sulfhydryl groups in proteins leading to damage in CNS and kidney; *contaminated fish, metallic mercury released from dental amalgams
What is especially sensitive to methyl mercury
Developing brain
What allows methyl mercury and Metallic mercury to accumulate in the brain
Lipid solubility
What is the main protective mechanism against mercury
Intracellular glutathione
What are the harmful effects of arsenic
Toxicities in GI tract, nervous system, skin and heart; present in Chinese and Indian herbal medicine; arsenic trioxide is treatment for acute promyelocytic leukemia
What are the most toxic forms of arsenic
Arsenic trioxide, sodium arsenide, and arsenic trichloride; causes acute GI, CV an CNS toxicities that are often fatal; attributed to interference with ox phos
What are the characteristics of arsenic poisoning
- neur effects 2-8 weeks after exposure consisting of sensorimotor neuropathy that causes paresthesias, numbness, and pain
- chronic exposure causes skin changes consistent of hyperpigmentation and hyperkeratosis
- increased risk for development of CA, particularly of lungs, bladder and skin
How do arsenic induced skin tumors differ from those caused by sunlight
Often multiple and usually appear on palms and soles
What are the harmful effects of cadmium
Preferentially toxic to kidneys and lungs *relatively modern problem; mining and batteries; food is most important source of exposure
What does the uptake of cadmium require
Transporters such as ZIP8 (normally transports zinc)
What are the principle toxic effects of cadmium
Obstructive lung disease caused by necrosis of alveolar epithelial cells and renal tubular damage that can progress to ESRD; can also cause skeletal abnormalities associated with calcium loss *in japan causes disease of osteomalacia and osteoporosis with renal disease; also have elevated risk of lung CA
What is Minimata disease
Exposure of fetus to high levels of mercury -> leads to CP, deafness and blindness
What can exposure to organic solvents cause
Ie: chloroform and carbon tetrachloride; used in degreasing and dry cleaning; causes dizziness and confusion, leading to CNS depression and even coma; lower levels toxic to kidneys and liver; *exposure to benzene increases risk of leukemia (oxidized to toxic metabolites by CYP2E1 that disrupt differentiation of hematopoietic cells in BM leading to risk of acute myeloid leukemia)
What can exposure to polycyclic hydrocarbons cause
Released during combustion of fossil fuels; present in tar and soot; most potent carcinogens -> lung and bladder CA
What can exposure to organochlorines cause
Synthetic lipophilic products that resist degredation; used as pesticides (DDT-used as insecticide in malaria areas), dioxin also an example; disrupts hormonal balance
What can dioxins and PCBs cause
Skin disorders such as folliculitis and dermatosis known as chloracne -> acne, cyst formation, hyperpigmentation, and hyperkeratosis generally on face and behind ears; can also cause abnormalities in liver and CNS; PCBs induce CYPs -> abnormal drug metabolism
What does inhalation of mineral dust cause
Chronic, nonneoplastic lung disease known as pneumoconioses, most commonly from exposure to coal dust, silica, asbestos, and beryllium *exposure of asbestos extends to family members of those exposed
What does exposure to vinyl chloride cause
Angiosarcoma of liver, uncommon type of liver CA
What does exposure to bisphenol A (BPA) cause
*lines water bottles; causes endocrine disruption; linked to heart disease
How long does the risk of lung cancer persist after smoking cessation
30 years
What is the direct irritant effect of cigarette smoke on the lungs
Causes inflammation and increased mucus production (bronchitis); also causes recruitment of leukocytes with increased elastase production leading to emphysema
What are the most important chemicals in cigarette smoke implicated in cancer
Polycyclic hydrocarbons and nitrosamines; CYPs metabolize these carcinogens, some intermediates of which can form DNA adducts which can cause mutations in oncogenes and tumor suppressors
What are the organ specific carcinogens in tobacco smoke
Lungs and larynx: polycyclic hydrocarbons, NNK, polonium 210
Esophagus: NNN
Pancreas: NNK
Bladder: 4-aminobiphenyl, 2-naphthylamine
Oral (smoking):polycyclic aromatic hydrocarbons, NNK, NNN
Oral (snuff): NNK, NNN, polonium 210
Which of the tobacco constituents is carcinogenic
Tar, polycyclic aromatic hydrocarbons, benzopyrene, nitrosamines
Which of the smoke constituents are toxic to cilia
Nitrogen oxides, formaldehyde
Which of the tobacco smoke constituents are tumor promotors
Phenol, and nicotine
Besides lung cancer, what other diseases is smoking linked to
- esophageal, pancreatic, bladder, kidney, cervical and bone marrow cancer
- nonmalignant conditions -> emphysema, chronic bronchitis, COPD
- atherosclerosis, MI (due to increased platelet aggregation, decreased myocardial oxygen supply accompanied by increased demand)
- spontaneous abortions and preterm birthday and intrauterine growth retardation
How can you measure passive smoke inhalation in non smokers
Blood levels of cotinine (metabolite of nicotine)
What happens to alcohol in the blood
Oxidized to acetaldehyde in liver by alcohol DH, ethanol oxidizing system (at high BAC levels) and catalase (very minor importance); acetaldehyde then metabolized. To acetate by acetaldehyde DH, which is then used in mit respiratory chain
Where does oxidation by alcohol DH take place
Cytosol
Where is the CYP 450 system located
ER
Where does oxidation of acetaldehyde occur
Mitochondria
What is the microtonal oxidation system
CYPs (particularly CYP2E1) located in SER; alcohol induces CYPs -> when alcohol high in the blood, delays other drug metabolism
What is acetaldehyde responsible for the development of
Oral cancers; also Asians have very low acetaldehyde DH activity due to substitution of lysine for glutamine at residue 487; even one deficient copy renders activity ineffective because dominant negative -> causes nausea, flushing, tachycardia, and hyperventilation
What is the effect of alcohol oxidation on NAD/NADH
Reduces NAD to NADH; NAD is required for FA oxidation in liver and conversion of lactate into pyruvate -> deficiency causes fatty liver in alcoholics and lactic acidosis (increases NADH/NAD ratio)
What does alcohol cause the release of in the gut
Endotoxins from gran negative bacteria in intestinal flora -> stimulates production of TNF and other cytokines leading to hepatic injury
Where does acute alcoholism exert its main effects
CNS, can induce reversible hepatic and gastric changes (acute gastritis/ulceration)
What does chronic alcoholism cause
- liver: alcoholic hepatitis and cirrhosis -> portal HTN and increased risk of hepatocellular carcinoma
- GI: massive bleeding from gastritis, gastric ulcer, esophageal varices
- thiamine (B1) deficiency: causes peripheral neuropathies and wernicke’s korsakoff syndnrome, cerebral atrophy, cerebellar degeneration and optic neuropathy
- CV: dilated congestive cardiomyopathy, increased risk of HTN and decreased HDL (increasing coronary heart disease)
- acute and chronic pancreatitis
- CA of oral cavity, esophagus, liver and in women, breast
What are the characteristics of fetal alcohol syndrome
Microcephaly, growth retardation, facial abnormalities in newborn and reduction in mental functions and child grows older *first trimester particularly harmful
What is the agent responsible for alcohol-induced laryngeal and esophageal cancer
Acetaldehyde