Connexin expression and junction formation accentuates the growth inhibitory effect of 9-CRA, ATRA and androgens in LNCaP cells.

<p>LNCaP-P, LNCaP-N and LNCaP-32 cells were seeded at a clonal density in 6 cm dishes in triplicate (2×10³ cells per dish). After 24 h, cells were treated with the indicated concentrations of 9-CRA, ATRA and MB. Cells were grown until they formed visible colonies (21 d for LNCaP-P and LNCaP-N and 33 d for LNCaP-32). Medium was changed every 4 d. Colonies were fixed with formalin and stained with crystal violet as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032846#s2" target="_blank">Materials and Methods</a>. Note that the growth of LNCaP-32 cells is profoundly inhibited upon 9-CRA, ATRA and MB treatment as colonies are barely detectable.