Fig. 7.

The 1,25 dihyroxyvitamin D3 (vitamin D3) increased DNA repair-related gene expression in HuLM cells. a HuLM cells were treated with 100 nM of vitamin D3 for 3 d. Ethanol was used as vehicle control. Real-time PCR analysis of mRNA levels of DNA double-strand break (DSB) repair-related genes, including homologous recombination DNA DSB sensors (RAD50, NBS1, MRE11), mediators and effectors (CHECK1, CHECK2, BRCA1), DSB binding (BRCA2, RAD51), cell cycle check point control (RAD17) and mismatch repair (MSH2, EXO1) were measured. The mRNA levels were normalized to 18 S rRNA, and normalized values were used to generate the graph. Data are presented as the mean ± SEM of triplicate measurements. *P < 0.05, ***P < 0.001. The experiment was repeated twice. b The prime PCR DNA damage gene expression array was used to identify additional DNA repair genes which show differential expression between vitamin D3 and vehicle-treated cells