RESULTS	In line with the in vivo data , in vitro functional studies showed that cells treated with 25 ( OH ) D for 24 h had increased VDR expression , and activated the mechanistic target of rapamycin ( mTOR ) / S6 kinase ( S6K ) pathway , enhanced Ki67 protein concentrations , and induced QM7 cell proliferation compared with untreated or cholecalciferol-treated cells .\