question

What is cancer caused by?

answer

The malfunction or mutation of genes involved in cell division and cell proliferation.

question

2 Mutational Routes

answer

Stimulation and Inhibition

question

Stimulation

answer

Leads to tumor formation - oncogene.

question

Inhibition

answer

Causes inactivity.

question

Oncogene

answer

A gene with the potential to cause cancer.

question

2 Properties that define Cancer Cells

answer

Autonomy and Anaplasia

question

Autonomy

answer

Cancer cells act independently from normal cell functions.

question

Anaplasia

answer

Loss of differentiation. Cancer cells lose its ability to function normally, control growth, and control division.

question

Transformation

answer

Process by which a normal cell becomes a cancerous cell.

question

Tumor Grading

answer

Estimates differentiation of cancer cells. 4 Grades.

question

Grade I

answer

Well differentiated. Tumor closely resembles the tissue of origin and retains some specialized function.

question

Grade II

answer

Moderately differentiated. Tumor has less resemblance to tissue of origin. More variation in size and shape of tumor cells; increased mitoses.

question

Grade III

answer

Poorly to very poorly differentiated. Tumor does not closely resemble tissue of origin. Much variation in size and shape of tumor cells; greatly increased mitoses.

question

Grade IV

answer

Very poorly differentiated. Tumor has no resemblance to the tissue of origin. Great variation in size and shape of tumor cells.

question

Cell Differentiation

answer

Proliferation cells are transformed into different and more specialized cell types, which determines the microscopic characteristics of the cell, function, and lifespan. Adult cell has all its specific sets of characteristics and can no longer divide.

question

Benign Neoplasms

answer

Benign tumor that has lost its ability to suppress the genetic program for cell replication but retain normal cellular differentiation.

question

Benign Neoplasms grow by:

answer

Expansion, not infiltration.

question

Benign Neoplasm Properties

answer

Capsule is mark of demarcation. Usually do not cause death. Known to secrete abnormal hormones.

question

Malignant Neoplasms

answer

Destructive tumors that grow rapidly, spread widely, and tend to cause death. Robs normal tissue from blood, nutrients, space, and release enzymes and toxins that destroy themselves and other tissues.

question

Destructive nature of Malignant Neoplasms due to:

answer

Lack of cell differentiation, cell characteristics, rate of growth, and ability to spread and metastasize.

question

Tumors are classified on the basis of:

answer

Tissue of origin, malignancy, degree of differentiation, and anatomic site.

question

Carcinomas

answer

Cancers of epithelial tissues.

question

Sarcomas

answer

Cancers of connective tissues.

question

Lymphomas

answer

Cancers of lymphatic tissues.

question

Gliomas

answer

Cancers cells involving the glial cells of the CNS.

question

Leukemias

answer

Cancer of the blood-forming organs (primarily bone marrow).

question

7 Standard Features of Cancer Cells

answer

Local increase in cell #, loss of normal arrangement of cells, variations in cell shape and size, increased nuclear size, increase in total DNA, increase in mitotic activity, abnormal mitoses and chromosomes.

question

Cancer Cell-Surface Changes: Decrease in Glycoproteins and Glycolipids.

answer

Altered receptor density or configuration of the cell surface. Decreased communication and cell signaling. May enhance the immune defense against cancer.

question

Cancer Cell-Surface Changes: Protease

answer

Cancer cells secrete plaminogen-activation factor which activates protease. Protease activation is needed before the expression of a malignant cell can be changed.

question

Cancer Cell-Surface Changes: Altered Anchoring Junctions

answer

Normal cells cannot divide or proliferate unless they are anchored. Cancer cells exhibit anchorage independence. Allows cells to metastasize.

question

Cancer Cell-Surface Changes: Altered Gap Junctions

answer

Tumors block gap junctions which regulate metabolic communication between cells.

question

Gap Junctions

answer

Allow ions and small water-soluble molecules to pass from the cytoplasm of one cell to the cytoplasm of another cell.

question

Tumor Cell Markers

answer

Substances produced by cancer cells that are found on tumor plasma membranes or in the blood, spinal fluid, or urine.

question

3 Uses of Tumor Cell Markers

answer

Screen and identify those at high risk for cancer. Help diagnose the specific type of tumor. Observe clinical course of cancer.

question

Tumor Cell Markers: Hormones

answer

Some tumors produce excess hormones. hCG (human chorionic gonadotropin) is one of the best tumor markers.

question

Adrenocorticoptropic Hormone (ACTH)

answer

Lung Cancer or Pituitary Cancer hormone tumor cell marker.

question

Antidiuretic Hormone (ADH)

answer

Lung Cancer hormone tumor cell marker.

question

Tumor Cell Markers: Enzymes

answer

Expressed in the circulation when the tumor is very large or widespread metastasis has occurred.

question

Tumor Cell Markers: Genes

answer

Presence of chromosomes or oncogenes inside the cell. (Ph1)

question

Philadelphia Chromosome (Ph1)

answer

First chromosome marker identified. Present in 95% of patients with chronic myelocytic leukemia.

question

Tumor Cell Markers: Antigens

answer

Expressed as a result of reactivation of genes turned off at the end of fetal development. Elevated levels of prostate specific antigen (PSA) or alpha fetoproetein.

question

Carcinoembronic Antigen (CEA)

answer

Tumor cell maker with elevated serum levels found in patients with colon, pancreatic, and breast cancers.

question

Causes of Cancer

answer

Gene-environment interaction, Inherited genes, Oncogenic viruses.

question

Causes of Cancer: Gene-environment Interaction

answer

Environmental agents cause cancer by increasing frequency of mutations such as cigarette smoke, carcinogens, x-rays, and UV light.

question

Causes of Cancer: Inherited Genes

answer

Certain oncogenes can be inherited such as Retinoblastoma (childhood cancer of the eye), Wilms tumor (childhood cancer of the kidney), and breast cancer.

question

Causes of Cancer: Oncogenic Viruses

answer

Cancer causing viruses that cause a specific type of malignant or benign tumor in susceptible individuals. Divided into 2 groups by nucleic acid: RNA and DNA viruses.

question

3 Main Types of Oncogenic DNA Viruses

answer

1. Papovaviruses 2. Adenoviruses 3. Herpes-viruses

question

Cancer of the Cervix and Hepatocellular carcinoma account for:

answer

80% of virus linked cancer.

question

Risk factor for Hepatocellular Carcinoma

answer

Hepatitis B.

question

2 Other Viruses Implicated as Causing Cancer

answer

1. Human Immunodeficiency Virus (HIV) - associated with B-cell lymphoma or Kaposi Sarcoma (rare form of blood vessel cancer in the skin). 2. Herpes Simplex Virus (HSV) - associated with anogenital and oral cancers.

question

Carcinogenesis

answer

The process of tumor development.

question

Cancer Development Stages (3)

answer

1. Initiation - Causes irreversible changes to DNA after exposure to a carcinogen. 2. Promotion - Initiated cells become cancerous. 3. Progression - Cells become more biologically defective.

question

Environmental Risk Factors for Cancer

answer

Tobacco use, dietary sources of carcinogens (charbroiled beef), nitrates in fish and meat, low fiber diets, polyunsaturated fatty acids yield free radicals that are toxic, alcohol, obesity, sexual behavior, air pollution, occupation (asbestos), UV radiation, and Ionizing radiation.

question

Cigarette Smoke Factor

answer

Most important cause of lung cancer. Increases incidence of cancer of the bladder, pancreas, and to a lesser extent kidneys, larynx, oral cavity, and esophagus.

question

Diet Risk Factors

answer

Nitrates in fish and meat increase risk of gastric cancer. Certain ingested fats increase bile acids and cholesterol metabolites in feces increasing risk of colorectal cancer. Low fiber increase colon cancer risk.

question

Omega-3 and Selenium-containing Enzymes

answer

Decrease the number and size of tumors (03) and cause destruction of free radicals (SE). SE also decrease mortality from lung, colon, rectal, and prostate cancers.

question

Alcohol Risk Factors

answer

Increase risk for cancer of mouth, pharynx, larynx, esophagus, liver especially when combine with smoking.

question

Sexual Behavior Risk Factors

answer

Increased risk of cervical cancer is related to age of first sexual encounter and # of partners. HPV virus (most common cause for abnormal pap smears).

question

UV Radiation Risk Factors

answer

Basal cell and squamous carcinoma risk increased. Melanoma.

question

Ionizing Radiation Risk Factors

answer

Emissions from x-rays inhibits cell division and causes alterations in DNA. Can cause leukemias and solid tumors of thyroid, breast, and salivary glands.

question

Air and Occupation Risk Factors

answer

Air: Radon increases risk of lung cancer. O: Asbestos exposure accounts for largest number of occupational cancer of the lungs. Manufacturing of dye, rubber, paint, and aromatic amines cause bladder cancer.

question

4 Type of Cancers occur in Hormone Responsive Tissues

answer

Breast, Endometrium, Ovary, Prostate.

question

Research on Hormones and Caner focuses on:

answer

The direct actions of the sex steroids (estrogen, testosterone, and progesterone).

question

Proliferation

answer

Process of cell division. Adaptive mechanism for replacing body cells.

question

Differentiation

answer

Process of specialization where by new cells acquire the structure and function of the ones they replace.

question

Doubling Time

answer

The amount of time it takes a mass to double its cell population.

question

Cells That Do Not Proliferate or Divide

answer

Well-differentiated neurons, skeletal cells, and cardiac muscle cells.

question

Parent Cells

answer

Continue to divide and reproduce. (blood, skin, liver cells)

question

Undifferentiated Stem Cells

answer

Cells that can enter the cell cycle and produce large numbers of parent cells when the need arises.

question

Tumor Spread

answer

Direct invasion of contiguous organs or local spread. Metastases to distant organs by lymphatics and veins. Metastases through implantation.

question

3 Step Sequence of Tumor Invasion

answer

Attachment, Degradation, and Locomotion

question

Tumor Invasion: Attachment

answer

Step 1. The tumor cell attaches to extracellular matrix and receptors on the tumor bind to pars to the basement membrane of the extracellular matrix.

question

Tumor Invasion: Degradation

answer

Step 2. The tumor cell releases proteases which break down the matrix.

question

Tumor Invasion: Locomotion

answer

Step 3. Migration of the tumor cell through the degraded basement membrane. Enables the tumor to spread from the blood vessel into interstitial tissue.

question

Metastasis

answer

Spread of cancer cells from primary site of origin to distant site. The challenge of reducing cancer mortality is to control this.

question

3 Mechanisms of Metastasis

answer

Direct or Continuous Extension Lymphatic Spread Bloodstream Dissemination

question

Continuous Extension

answer

Metastasis in which tumors extend into several areas without breaking from the parent tumor which include tissue spaces, lymph and blood vessels, body cavities, and cerebrospinal spaces.

question

Lymphatic Spread

answer

Metastasis by lymphatics involving the invasion and penetration of tumor cells into lymphatics. Tumor cells carried to the lymph nodes. Often, a mass in the region lymph node is evidence of this metastasis.

question

Bloodstream Dissemination

answer

Metastasis that is complex and requires tumor cells to detach from blood vessels and spread to distant organs. Involves getting past host defenses, surviving the mechanical trauma of the bloodstream, and lodge in the vascular bed of the target organ.

question

Frequent Sites of Distant Metastasis

answer

Lung - multiple including brain Colorectal - liver, lungs Testicular - lungs, liver Prostate - bones, lungs, liver, endocrine glands, CNS Breast - skeleton, lungs Head and Neck - lymphatics, liver, bone Ovarian - peritoneal surfaces, diaphragm, liver

question

Cachexia

answer

Wasting syndrome. Most severe form of malnutrition. Progressive weight loss despite normal intake.

question

Leukopenia

answer

Decrease in white blood cell count.

question

Thrombocytopenia

answer

Abnormally low platelets.

question

Symptoms of Cancer

answer

Pain, fatigue, cachexia, anemia, leukopenia, infection, thrombocytopenia.

Pathophysiology – Biology of Cancer – Flashcards

Unlock all answers in this set

Haven't found what you were looking for?

Search for samples, answers to your questions and flashcards