The Washington Post published a story yesterday stating that Personal Health Beliefs are Largely Hit and Myth. The story discusses the results of an American Cancer Society (ACS) study released last week, which will be published in the September 1st issue of the journal Cancer.
The cell cycle is a series of ordered events that occur in a cell between it’s initial formation and eventual duplication and division into two daughter cells. Cells in the human body normally reproduce up to ~50 times , doubling their number with each cell cycle. Stem cells provide a pool of dividing cells to replace those that have died.
Interphase, the period between cell divisions, is where most cells remain for at least 90% of the cell cycle. Interphase consists of three phases: G1 (for gap 1), S phase (for synthesis) and G2 (for gap 2). During G1, the cell undergoes rapid growth and metabolic activity, including production of RNA and synthesis of protein. For the cell to divide and produce an identical copy of itself, its genome must be duplicated. DNA replication occurs in S phase. During G2, cell growth continues and the cell prepares for division. Cell division or mitosis occurs in M phase.
In normal cells, during G1 there are specific genes that control the speed of the cell cycle. These genes, called tumor suppressors and oncogenes, are mutated (meaning damaged) in cancer cells and can result in uncontrolled reproduction. Additionally, unlike normal cells, cancer cells do not stop reproducing after ~50 divisions. Thus, a cancer is an uncontrolled proliferation of cells.
In 2003, cancer deaths in the United States decreased by 369 deaths compared to 2002, the first drop seen since 1930. In 2004, the decrease in cancer deaths was eight times greater – 3,014 deaths – than in 2003, according to a report published in the latest issue of the American Cancer Society (ACS) journal CA: A Cancer Journal for Clinicians .
Experts are attributing the decreases to declines in smoking, earlier detection and more effective treatment of tumors. The three most common cancers — breast cancer, prostate cancer and colorectal cancer – show a decrease in death rates, with the largest change from colorectal cancer. Experts attribute much of the credit for the reduction in colorectal cancer to screening exams and the early detection of polyps that can be removed before they become cancerous.