Bortezomib synergistically increases ATRA-induced cell differentiation in SH-SY5Y and CHP126 cells.

<p>SH-SY5Y (A) and CHP126 (C) cells were treated with 5.0 nM bortezomib, 10.0 nM ATRA and 5.0 nM bortezomib plus 10.0 nM ATRA, 5.0 µM ATRA, as well as under control conditions. The morphology of the cells was observed by microscopy at the same magnification. The microphotographs shown are representative of three different experiments. The images were analyzed with the Leica software to determine the relative lengths of the neurites (B and D). Data are shown as the means ± SE (n = 3). SH-SY5Y and CHP126 cells were incubated as above, and realtime-PCR was performed to detect the expression of RET, GAP43 and TrkB (E and F). SH-SY5Y cells were incubated as above, and immunofluorescence was performed to detect the expression of tau and β tubulin III (G and H). Western blotting (I) was used to detect the expression of tau and β tubulin III in CHP126 cells. BTZ = bortezomib.