Figure 3
PER 2 expression reduces MCF-7 cell growth in soft agar. Soft agar clonogenic assays were performed with MCF-7 cells. MCF-7 cell were transfected with pTracer™-CMV2 or pTracer™-CMV2-hPer 2 and sorted. Two thousand five hundred cells per well were seeded in 12-well plates (3.8 cm2) in culture medium containing 0.35% low-melting agarose over a 0.7% agarose base layer and incubated for 12 days. Colonies larger than 100 μm in diameter were counted.