cancer is the abnormal growth of cells caused by uncontrolled cell division. tumor suppressor genes are genes that encode protein products whose normal function is to protect cells from becoming cancerous. when a loss-of-function mutation occurs in a tumor suppressor gene, a cell may progress to a cancerous state. in some cases, a loss-of-function mutation results in a loss of gene expression. in the tumor cell microarray, choose spots among those listed below that may represent mrnas that encode proteins that function as tumor suppressors. choose all that apply.