Fig. 6. Effect of hypoxia on RhoA and Cdc42 mRNA levels in renal cell carcinoma. Total RNA was isolated from Caki-1 cells in normoxia and hypoxia. RT-PCR amplification was performed using primers for RhoA for 15 to 30 cycles in order to define optimal conditions (A). At 25 cycles, RT-PCR analysis for RhoA (183 bp), Cdc42 (400 bp), and -tubulin (321 bp) were carried out on total RNA isolated from cells incubated under hypoxia for up to three hours (B).