Unit 1- The Nature and Hallmarks of Cancer Flashcards
What is cancer?
- group of diseases that originate from a LOSS OF CONTROL of cell division/ differentiation/ survival/ death mechanisms
What is the loss of cellular control in cancer a result of?
Mutations = dynamic changes in cell genome
What results in the uncontrollable proliferation of cells into a mass? (tumor)
- mutation (changes in cell genome) in cooperation with a permissive microenvironment
Do all cancers form a tumor mass?
No- ex) leukemia
What are the hallmarks of cancer?
- Sustaining proliferative signaling
- Evading growth suppressors
- Avoiding immune destruction
- Enabling replicative immortality
- Tumor-promoting inflammation
- Activating invasion/ metastasis
- Inducing angiogenesis
- Genome instability/ mutation
- Resisting cell death
- Deregulating cellular energetics
What is the first report of cancer?
- reported in the Smith Papyrus > bulging mass under breast
- Imhotep, an Egyptian physician
What was the first “true” evidence of cancer in humans?
- Osteosarcoma in mummy from the Atacama desert
What is the oldest case of cancer?
- Osteosarcoma in leg of 76 million yrs old dinosaur fossil in Alberta
What is the origin of the term carcinoma?
- first used by Hippocrates to describe solid tumors
- based on way blood vessels organized around tumors like a crab
What does the term carcinoma currently denote?
- malignant solid tumors of epithelial origin only
What is the difference between cancer/ carcinoma?
Cancer- malignant tumors of all types
Carcinoma- malignant solid tumors of epithelial origin only
What is the origin of the term oncology?
- Galen was the first to use onkos to describe tumors
Where do carcinomas originate from?
Epithelium
What are the 2 general types of tumors/ what are they based on?
Benign/ Malignant
- based on histological features/ expected clinical outcome
What is the difference between a benign/ malignant tumor?
Benign- confined to tissue of origin/ rarely cause harm
Malignant- invade locally and distantly/ form colonies in other organs
What are metastases?
- colonies malignant tumors form in other organs
What is metastasis?
- the process of distant invasion of malignant tumors
How are tumors classified based on cell of origin?
Epithelial > Squamous/ Adeno/ Atypical
Non-Epithelial > Sarcomas/ Hematopoietic/ Neuroectodermal
What are the types of carcinoma based on cell of origin?
Squamous cell carcinoma > arises from epithelium with protective function/ formed by flattened (squamous) cells
Adenocarcinoma > arises from epithelium with glandular/secretory function
Atypical carcinomas > do not fit above categories
What is an example of an atypical carcinoma?
Small cell lung carcinoma
What are some common sites of epithelial tumors?
Skin/ Mammary gland/ Prostate/ GI tract/ Lung
Can you have 2 types of carcinoma that arise from epithelium of same organ?
yes- ex) squamous cell carcinomas/ adenocarcinomas of both esophagus/ lung
What are some steps in the progression from normal > malignant epithelium?
Hyperplasia/ Metaplasia/ Dysplasia
What is hyperplasia?
- ↑ growth of cells/ tissue, but normal cell features/ histology
- typical of benign tumors