A proto-oncogene* is a gene that when mutated or expressed at abnormally-high levels contributes to converting a normal cell into a cancer cell. It is estimated that 1% of the ~21,000 genes in the human genome are proto-oncogenes.
In his talk, Gregory Longmore of Washington University in St Louis, Missouri, outlined some of the complex signaling pathways responsible for metastasis. Somehow, cancer cells break off from a primary tumor, break through the layer of cells that separates them from the bloodstream, and then spread to new sites.
Of the facts and figures Longmore cited, two struck me especially. Ninety percent of cancer patients are killed by metastases, not primary tumors. Ninety-nine percent of cancer cells that make their way into the bloodstream die. “Metastasis is incredibly inefficient,” he said.
{ Charles Day/Physics Today | Continue reading | More: Oncogenes }
