Expression of NEDD4-1, a PTEN regulator, in gastric and colorectal carcinomas.
Recent studies have disclosed that NEDD4-1 regulates PTEN activity by ubiquitination. NEDD4-1 negatively regulates PTEN in cytosol and acts as an oncogenic protein. By contrast, NEDD4-1 promotes PTEN nuclear import and acts as a tumor suppressor. Despite the importance of NEDD4-1 in PTEN regulation in cancer cells, expression of NEDD4-1 protein in cancer tissues is unknown. The aim of this study was to analyze NEDD4-1 expression in colorectal and gastric cancer tissues. We investigated NEDD4-1 protein expression in 103 colorectal and 60 gastric carcinoma tissues by immunohistochemistry using a tissue microarray approach. In the cancers, expression of NEDD4-1 was detected in 82 (80%) of the colorectal carcinomas and 45 (75%) of the gastric carcinomas in cytoplasm. By contrast, the normal mucosal cells of both stomach and colon showed no or very weak expression of NEDD4-1. There was no significant association of NEDD4-1 expression with clinicopathologic characteristics, including invasion, metastasis and stage. Our data indicate that NEDD4-1 overexpression is a feature of both colorectal and gastric carcinomas. The increased expression of NEDD4-1 in malignant gastric and colorectal cells compared to their normal epithelial cells suggests that NEDD4-1 expression may play a role in colorectal and gastric cancer development.
Kim
Sung Soo
SS
Department of Pathology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Yoo
Nam Jin
NJ
Jeong
Eun Goo
EG
Kim
Min Sung
MS
Lee
Sug Hyung
SH
D000230:Adenocarcinoma / Q000201:enzymology* / Q000473:pathology; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000473:pathology; D056827:Endosomal Sorting Complexes Required for Transport; D006801:Humans; D007150:Immunohistochemistry; D000075702:Nedd4 Ubiquitin Protein Ligases; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D040081:Protein Array Analysis / Q000379:methods; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000201:enzymology* / Q000473:pathology; D044767:Ubiquitin-Protein Ligases / Q000096:biosynthesis*
D056827:Endosomal Sorting Complexes Required for Transport; D000075702:Nedd4 Ubiquitin Protein Ligases; C000618483:Nedd4 protein, human; D044767:Ubiquitin-Protein Ligases; D051059:PTEN Phosphohydrolase