Lecturer
Introduction
Cell Growth Regulation Cell growth is the cell proliferation (the increase in cell numbers that occurs through repeated cell division). Cell growth is regulated by two groups of regulatory genes:
A. Proto-oncogenes (cellular oncogene, c-onc) Are normal genes which control cell proliferation Have the potential to contribute to cancer development if their expression is altered (changed into oncogenes) Oncogenes are genes that cause cancer
B. Tumor Suppressor Genes Include genes that inhibit cell growth, fixing broken DNA or causing a cell to die Examples: P53, Rb (retinoblastoma) In normal cells, oncogenes are "switched off" or down-regulated by antioncogene proteins
