Module 12: Cancer Genetics Flashcards
Neoplasia
Uncontrolled cellular proliferation
Neoplasm
Mass or tumor resulting from neoplasia
Malignant
Tumor capable of invading (metastasizing) to neighboring tissue (cancer)
Benign
Tumors that do not invade other tissues (not cancer)
Sarcoma
Tumor arises from mesenchymal tissue (such as bone, muscle, connective tissue, nervous system)
Carcinomas
Tumor arises from epithelial tissue (such as lining of intestine, bronchi, mammary ducts)
Hematopoietic & Lymphoid
Originate in bone marrow and spread through lymphatic system & peripheral blood (such as leukemia & Lymphoma)
Oncogenes
Mutant allele of the proto-oncogene that facilitate malignant transformation by stimulating cell proliferation and inhibiting apoptosis
What do Tumor Suppressor Genes do?
- Regulate cell growth
- Loss of function mutation in both alleles contributes to developing cancer
- Inactivate genes that suppress cell proliferation
- Inactivate genes that regulate apoptosis
Mismatch Repair Genes
Maintain genomic stability
Proto-oncogene
Class of normal cellular protein-coding genes that promote growth and cell survival
Functions of Oncogenes
- Encode growth factors
- Encode growth factor receptors
- Membrane associated proteins
- Control transcription in the nucleus
Types of Tumor Suppressor Genes
- Gatekeeper TSG’s
- Caretaker or maintenance TSG’s
Gatekeeper TSG’s
Control cell growth to block tumor development
Caretaker or Maintenance TSG’s
Maintain the genome by repair of DNA damage
What is the function of genes that are mutated in cancer?
Regulate the cell cycle
What are proto-oncogenes?
Genes that control cell proliferation and apoptosis
What are common mechanisms to activate a proto-oncogene?
- Viral insertion into a gene
- Reciprocal translocation or creating a new gene function
- Point mutation from an environmental event
What is the likely outcome if one copy of a tumor suppressor gene is mutated in a gene pair?
Normal cell growth
(T/F) Mutations in multiple genes often determine the type of cancer and cancer growth.
True
What is the role of DNA mismatch repair genes in the cell cycle?
To identify and repair mistakes that occur during replication
