Hep Par 1 is diffusely expressed in non-neoplastic Barrett esophagus while it is frequently lost in related dysplasia and adenocarcinoma, suggesting decreased level of HepPar1 may represent an early event in Barrett-related tumor genesis.
Classic GHCs and fetal type gastrointestinal adenocarcinomas showed positive LIN28 in 21/47 (45%) and 10/46 (22%), SALL4 in 41/47 (87%) and 36/46 (78%), AFP in 30/46 (65%) and 33/46 (72%), glypican-3 in 31/41 (76%) and 24/38 (63%), Hep Par1 in 27/41 (66%) and 28/37 (76%), and CK7 in 15/40 (38%) and 25/38 (66%), respectively. p-CEA staining was seen in 19/44 (43%) classic GHCs.
In the present study, PAR-1 gene expression was determined in lung tissue from patients with non-small-cell lung cancer (NSCLC) using a combination of publicly available RNA microarray datasets and in house-made tissue microarrays including tumor biopsies of 94 patients with NSCLC (40 cases of adenocarcinoma, 42 cases of squamous cell carcinoma and 12 cases of other type of NSCLC at different stages).
A subset of gastric adenocarcinomas (71%) also showed reduced trypsinogen accompanied by reduction in PAR2, a G protein activated by trypsin, and a propensity to penetrate beyond the gastric wall (P = 0.001).