SERPINB5 and lip and oral cavity carcinoma: People with G/G homozygotes or with G/C heterozygotes of Maspin rs2289520 G/C polymorphism had a 2.07-fold (95% CI: 1.13–3.77; P = 0.01) and a 2.01-fold (95% CI: 1.09–3.70; P = 0.02) risk of developing oral cancer compared to those with C/C homozygotes after adjusting confound factors.