NES and lung cancer: Tests of heterogeneity between trials using the Q statistic showed no significant heterogeneity in the following analyses: nestin expression with cancer staging (positive/high nestin vs. negative/low nestin, P = 0.76, I2 = 0%), nestin expression with lymph node positivity (positive/high nestin vs. negative/low nestin (P = 0.67, I2 = 0%), and nestin expression with lung cancer stage, positive/high nestin vs. negative/low nestin (P = 0.98, I2 = 0%).