Unit 1 Study Guide - Cancer, Cell Injury, and Stress

Comprehensive practice questions covering cancer prevention trials, cellular injury mechanisms (including pump failure and necrosis), aging physiology, stress responses (hormones and indicators), and clinical screening guidelines.

Which substances were specifically tested in clinical trials for cancer prevention?

The substances include $\beta\text{-carotene}$, vitamin E, vitamin C, Selenium, retinol, zinc, riboflavin, and molybdenum.

What was the conclusion of clinical trials regarding traditional antioxidant vitamins or minerals for cancer prevention?

None produced convincing evidence to justify their use; many failed to reveal a benefit, and it is currently suggested to consume antioxidants via natural fruit and vegetable sources instead.

What steps must a tumor cell take to enter blood or lymphatic vessels?

Escape the basement membrane of the tissue of origin, move through the extracellular space, and penetrate the vessel's basement membrane.

How do tumor cells digest the basement membrane during invasion?

By binding to matrix components like laminin via specific receptors and releasing enzymes such as proteases and collagenases.

Failure of the $Na^+-K^+$ pump leads to the accumulation of which substance within the cell?

Sodium ions ($Na^+$), which creates an osmotic gradient for water entry.

What is the first manifestation of most forms of reversible cell injury?

Hydropic swelling (Oncosis).

What are the physical characteristics of a cell experiencing hydropic swelling?

Large, pale cytoplasm; dilated endoplasmic reticulum; and swollen mitochondria.

What are the three categories of intracellular accumulations?

1) Excessive amounts of normal substances (e.g., fat); 2) Abnormal substances due to faulty metabolism/synthesis; 3) Pigments and particles the cell cannot degrade.

What are the physiologic changes of aging in the musculoskeletal system?

Decreased muscle mass, increased bone demineralization, and increased joint degeneration, erosion, and calcification.

What are the physiologic changes of aging in the cardiovascular system?

Decreased vessel elasticity (increased pulmonary vascular resistance), heart muscle fiber hypertrophy, decreased filling capacity, decreased stroke volume, decreased baroreceptor sensitivity, and degeneration of vein valves.

The majority of human cancers ($90\,\%$) are classified as what?

Carcinomas, which result from the malignant transformation of epithelial cells.

What are the key abnormal behaviors of cancer cells?

Sustained proliferative signaling, escaping apoptosis, evading growth suppressors, replicative immortality, invasion and metastasis, proangiogenic signaling, reprogrammed energy metabolism (aerobic glycolysis), and evading immune surveillance.

What are the effects of increased Aldosterone during stress?

Reabsorption of sodium and increased excretion of potassium, high blood pressure, and increased extracellular fluid volume.

What metabolic effects do glucocorticoids produce during the stress response?

Catabolism of muscle, fat, lymphoid tissue, skin, and bone; liver gluconeogenesis; and opposing insulin in the transport of glucose into cells.

How do glucocorticoids affect the immune and inflammatory response?

They suppress the inflammatory response, increase neutrophil release, decrease new antibody release, and decrease T-lymphocyte production and function.

What are the functions of Cortisol in the body?

Affects protein metabolism, stimulates gluconeogenesis in the liver (sixfold to tenfold increase), preserves glucose for brain use, and promotes appetite and food-seeking behaviors.

What is true about the secretion and role of Aldosterone?

It is the primary mineralocorticoid secreted by the adrenal cortex; its release is triggered by the renin-angiotensin system (activated by the SNS) and it has the greatest effect on circulating volume.

What are the effects of endorphins during stress?

They raise the pain threshold, produce sensations of euphoria, and can attenuate the stress response during acute stress.

Disruption of the microbiome is primarily associated with which types of cancer?

Cancers related to the gastrointestinal tract and lungs.

What are the characteristics and origins of Oxytocin?

Synthesized by the hypothalamus and secreted by the posterior pituitary; associated with bonding (tend-and-befriend), childbirth, and lactation; has calming and analgesic effects; and has higher concentrations in females.

What term describes the behavioral adaptive response to a stressor?

Coping.

What are physical indicators of high stress?

Elevated blood pressure, increased muscle tension, elevated pulse and respiration, sweaty palms, fatigue, headaches, nausea/vomiting, hyperglycemia, and increased blood catecholamine levels.

What are behavioral or emotional indicators of high stress?

Anxiety, depression, increased substance use, mental exhaustion, loss of motivation, decreased productivity, and inability to concentrate.

What are the 'tail ends' of chromosomes that shorten with cell division?

Telomeres.

What is 'allostatic load'?

The wear-and-tear effect of adaptation on the body and mind caused by systems being chronically overactivated or underactivated.

What are the different categories of general stressors?

Physical, chemical, biological, social, cultural, and psychological.

What are the criteria for determining brain death (somatic death)?

Unresponsiveness, flaccidity, absence of brainstem reflexes, absence of respiratory effort without a ventilator, absence of electrical brain waves, and lack of cerebral blood flow.

What is the American Cancer Society (ACS) recommendation for cervical cancer screening for females aged 25–65?

Primary HPV testing every $5$ years; if unavailable, HPV and cervical cytology co-testing every $5$ years, or cervical cytology alone every $3$ years.

What factors determine the success of stem cell transplantation?

Age of the patient, closeness of tissue matching, stage of cancer, and the general health status of the patient before transplantation.

What is the term for inadequate delivery of blood to the cells?

Ischemia.

What does a tumor classification of 'T4' signify?

The tumor directly invades or adheres to adjacent structures.

What are examples of common paraneoplastic syndromes?

Hypercalcemia, Cushing syndrome (secondary to excess ACTH), and hyponatremia/water overload (secondary to excess ADH).

Which type of necrosis is specifically associated with neurons?

Liquefactive necrosis.

What type of cellular abnormality involves an increase in cell size?

Hypertrophy.