Significantly lower PDCD4 mRNA levels were detected in OSCCs from node-positive patients (N+) as compared with node-negative patients (N0) ( p = 0.0027 ). Median PDCD4 expression in node-positive tumors was 0.16 versus 0.34 in node-negative tumors. The x-axis shows the nodal status (N0, N+), and the y-axis represents PDCD4 mRNA levels normalized against GAPDH and normal oral mucosa. In normal oral mucosa tissues (used as baseline control sample), PDCD4 expression levels were defined as 1, according to the Delta Delta Ct method of data analysis. Error bars represent standard error.