BIOC 454- Midterm Exam Guide - Comprehensive Notes for the exam ( 88 pages long!)
16 Feb 2018
School
Department
Course
Professor
Document Summary
Cancer is caused by the accumulation of mutations that result in the activation of oncogenes and the inactivation of tumor suppressor: usually need bi-allelic inactivation of tumor suppressors, but some are haploinsufficient. 1- dominantly acting transforming genes which get activated a proto-oncogene (has properties associated with cancer) becomes an oncogene. One of first oncogenes was ras and it harbored different point mutations: mainly mutated at codons 12, 13, 59 and 61, many genes, mutated ras in 50% colorectal and 95% pancreatic cancer. A significant subset of acute nonlymphocytic leukemias, thyroid cancers and adenocarcinomas of the lung also contain such mutations. In most other tumor types (e. g. cancers of the breast, prostate, stomach, bladder, liver and brain), however ras mutations do not occur often if at all. As ras genes are ubiquitously expressed and presumably have similar functions in all cells, the basis for this tissue specificity is not understood. Ras is a crutial regulator of: cell shape, motility, growth.
