Cancer Flashcards
What cell type and location does carcinoma come from?
Arise from epithelial cells that cover external and internal surfaces
Lung,breast,colon
What cell type and location does sarcoma come from?
Arise from cells of supporting tissues
Bone,cartilage,fat
What cell type and location does leukaemia/lymphoma come from?
Arise from blood and lymphatic cells
Blood,bone marrow,lymph nodes
What causes tumour formation?
Uncontrolled proliferation
Disrupted balance between cell division & cell differentiation
What genes contribute to the development of cancer?
Oncogenes
Tumour suppressor genes
What are oncogenes?
Drive unrestrained cell proliferation and confer malignant characteristics to cell
Gain of function mutation
What are point mutations?
Single nucleotide substitution which causes a single amino acid substitution in the protein encoded by normal proto-oncogene
What are gene amplifications?
Increased no. Of copies of proto-oncogene
Produced in excessive amounts Altho the protein is normal
What are chromosomal translocations?
Part of one chromosome is removed and joined to another chromosome
What is local DNA rearrangement?
Insertions, deletions, inversions or transpositions of proto-oncogenes
What are insertional mutagenesis?
Retrovirus induced- viral DNA inserted into proto-oncogene
What is the function of tumour suppressor genes?
Regulate the cell cycle, DNA repair and cell death
Mutation in a tumour suppressor gene can disrupt function
What is the job of P53?
Blocks the replication of damaged or mutated cells
What is multi-step tumorigenesis?
Normal cells evolve into cells with increasingly neoplastic phoenotypes = tumour progression
TP takes place at myriad sites throughout human body
What is tumour progression driven by?
A sequence of randomly occurring mutations and epigenetic alterations in DNA
affected genes control cell proliferation,survival and other traits associated with the malignant cell phenotype
