Cell cycle Cell cycle The cell cycle, or cell-division cycle, is the series of events that take place in a cell leading to its division and duplication of its DNA (DNA replication) to produce two daughter cells. In bacteria, which lack a cell nucleus, the cell cycle is divided into the B, C, and D periods. The B period extends from the end of cell division to the beginning of DNA replication. DNA replication occurs during the C period. The D period refers to the stage between the end of DNA replication and the splitting of the bacterial cell into two daughter
DNA methylation in cancer lung cancers or non-small-cell lung cancer squamous cell carcinomas. The article Werner syndrome ATP-dependent helicase indicates the DNA repair gene "WRN" has a promoter that is frequently hypermethylated in a number of cancers, with hypermethylation occurring in 11% to 38% of colorectal, head and neck, stomach, prostate, breast, thyroid, non-Hodgkin lymphoma, chondrosarcoma and osteosarcoma cancers (see WRN). As discussed by Jin and Roberston in their review, silencing of a DNA repair gene by hypermethylation may be a very early step in progression to cancer. Such silencing is proposed to act similarly to a germ-line mutation in a DNA repair gene,