Due to high levels of ABCB1 gene expression being linked to poor prognosis of human pancreatic cancer [11] and the fact that ABCB1 2677TT and 3435TT genotypes were reported to be associated with increased overall survivals in gemcitabine treated postoperative pancreatic cancer patients [15], this study examined the association of ABCB1 genotype/haplotype with ABCB1 mRNA expression and the sensitivity to gemcitabine in several pancreatic cancer cell lines. Here, ABCB1 is linked to pancreatic neoplasm.