Neoplasia 1 Nicols Definitions and Pics Flashcards
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What is a neoplasm ?
A neoplasm (tumor) is an autonomous irreversible clonal benign or malignant cell proliferation outside of normal control by contact inhibition, hormones, etc.
What are 5 adjectives that commonly describe neoplasms ?
- It is autonomous 2. Irreversible 3. Clonal 4. Benign (or 5) 5. Malignant
What is a metastasis ?
A secondary site of a tumor that is discontinuous with the first
What is a neoplasm of the mesenchyme cell layer ?
Sarcoma
What is a malignant neoplasm of epithelial cell origin ?
Carcinoma
What does the mesenchyme give rise to ?
Connective tissue, Bone Cartilage, muscle Ect.
How do carcinomas spread ?
Lymph system
How do sarcomas spread ?
Hematogenosus - Lung or the liver
How do ovarian carcinomas spread ?
Seeding of the body cavities or surfaces
What is a mixed germ cell tumor ?
Teratoma - which is a malignant neoplasm made up of one or more germ cell layer
What is a mass of mature disorganized tissue indigenous to its site and is a developmental abnormality
Hamartoma
What is an ectopic rest or a mass of normal tissue present outside its normal site, also a developmental anomaly
Choristoma
What is a macroscopic projection above a mucosal ( or epidermal ) surface or a nodule on a stalk or on that surface
A polyp
What is polyp on a stalk considered
A Pendunculated Polyp
What is a polyp that is flat with the surface it manifests ?
A Sessile Polyp
What is a benign epithelial neoplasm forming glands or derived from glands ?
An Adenoma
What is anaplasia ?
Lack of visual differentiation of tumor cells giving them the appearance of primitive unspecialized cells
What are the features of anaplastic cells
(1) larger size than differentiated cells, (2) higher nuclear / cytoplasmic ratio: larger nuclei, less cytoplasm, (3) pleomorphic (varying in size and shape).
What is a Dysplasia? and what are the two types ?
- An unorganized growth 1. Congenital - embryonically abnormal organization of cells and acquired cellular atypia usually premalignant, +/- reversible 2. Acquired - dysplasia of glandular epithelium is usually called “atypical hyperplasia” or “atypical adenomatous hyperplasia”.
What is the formation of abundant fibrous stroma by some carcinomas ?
Demoplasia
What is the difference between stroma and parenchyma ?
The stroma, you recall, is the infrastructural part of a tissue or organ, opposite of parenchyma, which is the functional (business) part.
Tissue with all the cytologic (individual cell) features of malignancy without visible invasion is called … ?
Carcinoma in situ
What are some of the common causes of cancer ?
smoking, obesity, alcohol, diet, human papilloma virus (HPV), ultraviolet light, asbestos and many other factors. Smoking is a cause of cancers of lung (90% of them), mouth, pharynx, larynx, esophagus, stomach, pancreas, kidneys, bladder and (to a smaller extent) many other types. Obesity is a cause of 14% of cancers of men and 20% of cancers of women in the US
What type of disease is neoplasia ?
Genetic
What are the six properties of malignant cells ?
(1) self-sufficiency in growth signals, (2) insensitivity to anti-growth signals, (3) evasion of apoptosis, (4) sustained angiogenesis, (5) limitless replicative potential and (6) the ability to invade tissue and metastasize.
What are the two major mutations that lead to cancer ?
Tumor suppressor genes normally apply brakes to cell proliferation. When mutated your cellular brakes wont work oncogene- is more like having you accelerator pinned to the floor
What does Rb do ?
*Rb binds to E2F when hypophosphorylated and sequesters E2F to prevent activation of Cyclin E (Halts cell cycle at G1-S)
*Rb is phosphorylated by Cyclin D CDK4/6 and releases E2F, –> transcription of S phase genes and the cell progresses through the cycle
**Normally when the cell reaches the M phase the phosphate groups are removed from Rb and it will rebind to E2F and the cell cycle will be inhibited
What does loss of control of Rb cause ? What is the mechanism ?
Retinoblastoma When Rb is phosphorylated by cyclin D-CDK4, cyclin D-CDK6 and cyclin E-CDK2 complexes, it releases E2F. E2 F then soon activates genes starting up cell proliferation.
**2 Hit mutant hypothesis
**Rb also stimulates macrophage, adipocyte, melanocyte and many other differentiation cell signals so loss of control is a big deal.
What does APC do ?
APC tumor suppressor gene controls intestinal stem cell proliferation by WNT signaling. The APC gene product breaks down beta-catenin so that it does not bind to transcription factor TCF that will allow the malignant transformation of neoplastic cells. This allows for down regulation of E-Cadeherin to decrease cellular adhesion.
What does p53 do ?
It prevents propagation of genetically damaged cells by binding to DNA, arresting the cell cycle to enable DNA repair and initiating apoptosis, if repair is impossible