FIGURE 2.
Low doses of all‐trans retinoic acid stimulate growth of prostate cancer cell lines. (A) Serum‐free adapted LNCaP, PC‐3 and DU145 cells were treated with ATRA at the indicated concentrations. Results are presented as the mean number of cells recovered (±SD). (B) The ability of serum‐free adapted LNCaP, PC‐3, or DU145 cells to form colonies in response to 10−10 M and 10−6 M ATRA as indicated was analyzed by methylene blue staining. Results are presented as mean colony‐forming efficiencies (±SD). (C) Serum‐free adapted LNCaP cells were treated with 10−10 M and 10−6 M ATRA as indicated and assessed for ability to form holoclone/meroclone, or paraclone colonies. Results are presented as the percentage of colony types as indicated. Statistical significance is represented as described in Section 2