Cell cycle dependent genes from the gastric cancer cell MKN45 can affect tumorigenesis.

BACKGROUND/AIMS: To investigate the cell cycle dependent genes involved in gastric tumorigenesis, possibly determining the relationship between the cell cycle and tumorigenesis. METHODOLOGY: MKN45 cells were collected every hour from Oh to 12h after release from G2/M and G1/S blocks. Nine samples (a-i), chosen at key times of the cell cycle, were prepared for RNA isolation and cDNA microarray analysis. RESULTS: In 2001 viable clones, 959 genes showed periodic variations during the cell cycle. Among 2001 genes that were clustered, a series of up-regulated genes were assigned to different cell cycle phases. Many periodically dependent genes in the cell cycle were ubiquitously expressed and participated in various cell physiological functions, such as transcription, translation, ubiquitination and signal transduction. These cell cycle dependent genes could affect cancer cell proliferation, apoptosis, activation of oncogenes and inactivation of tumor suppressor genes. CONCLUSIONS: We provided a comprehensive understanding of the gene expression profile involved in gastric cancer cell cycles and laid a foundation for further research on mechanisms of gastric tumorigenesis.