['Class III beta-tubulin (TUBB3) reduces microtubule stability and confers resistance to microtubule-stabilizing taxanes, including paclitaxel and docetaxel. Pancreatic ductal adenocarcinomas show limited responsiveness to taxanes, but little is known of the underlying mechanisms. The aim of this study was to examine TUBB3 expression in pancreatic cancer cell lines, invasive pancreatic adenocarcinoma and pancreatic intraepithelial neoplasia (PanIN).', 'Reverse transcriptase-polymerase chain reaction and Western blot were used to study TUBB3 expression in pancreatic cancer cell lines. Immunohistochemistry was employed to assess TUBB3 in pancreatic cancer specimens, including 75 invasive adenocarcinomas and 41 PanIN precursor lesions. TUBB3 was undetectable in non-neoplastic ducts of the pancreas. In contrast, the vast majority (78-93%) of pancreatic ductal adenocarcinomas demonstrated either diffuse or focal TUBB3 expression. TUBB3 was found to increase progressively in PanIN lesions from 3/16 of PanIN-1 (19%), 5/17 of PanIN-2 (29%) to 5/8 of PanIN-3 lesions (63%).'] Is class III beta-tubulin , a marker of resistance to paclitaxel , overexpressed in pancreatic ductal adenocarcinoma and intraepithelial neoplasia?