FIGURE 6.

TSA-mediated differentiation of PANC-1 cells is required for the expression of NDRG1 under hypoxia. A, Expression of NDRG1 mRNA levels was determined by real-time PCR as described in the Materials and Methods. Cells were treated with TSA for 3 days under normoxia including 24 hours under hypoxia (1.5% O₂). Columns: means of three values of three separate experiments; bars, SD. **P < 0.01. B, Expression of phospho-NDRG1, total NDRG1, and CA II proteins in cells monitored for 4 days. Total proteins were transferred to nitrocellulose membranes and probed with a sheep anti-phospho-NDRG1 antibody. The membrane was stripped and reprobed with a sheep anti-NDRG1 antibody and with a rabbit anti-CA II antibody. β-actin (42 kDa) was used to compare loading. The result shown is representative of three independently performed experiments. C, Photomicrograph showing the cell phenotype in each condition. D, Expression of CA II and NDRG1 proteins. α-tubulin was used as a loading control.