Expression of 16 kDa proteolipid of vacuolar-type H(+)-ATPase in human pancreatic cancer.
Recent studies have shown that bafilomycin A1-sensitive vacuolar-type H(+)-ATPase (V-ATPase) plays important roles in cell growth and differentiation. However, there is no published study that has focused on the expression of V-ATPase in human tumour tissues. This study was designed to examine the mRNA and protein levels for the 16 kilodalton (kDa) proteolipid of V-ATPase in human pancreatic carcinoma tissues. We first investigated the mRNA level for V-ATPase in six cases of invasive pancreatic cancers and two normal pancreases, using reverse transcription-polymerase chain reaction technique. Then, we examined immunohistochemically the level of V-ATPase protein in 49 pancreatic cancers and ten benign cystic neoplasms of the pancreas, using antisera raised against the 16 kDa proteolipid. There was a notable difference in the level of V-ATPase mRNA between normal and pancreatic carcinoma tissues, with no evident difference in the expression of the beta-actin gene. Immunohistochemically, 42 out of 46 invasive ductal cancers (92%) displayed a mild to marked immunoreactivity for V-ATPase in the cytoplasm, whereas neither non-invasive ductal cancers nor benign cystic neoplasms expressed detectable immunoreactive proteins. These findings suggest that the overexpression of V-ATPase protein is characteristic of invasive pancreatic tumours. V-ATPase may play some crucial roles in tumour progression.
Ohta
T
T
Department of Surgery (II), School of Medicine, Kanazawa University, Japan.
Numata
M
M
Yagishita
H
H
Futagami
F
F
Tsukioka
Y
Y
Kitagawa
H
H
Kayahara
M
M
Nagakawa
T
T
Miyazaki
I
I
Yamamoto
M
M
Iseki
S
S
Ohkuma
S
S
D000230:Adenocarcinoma / Q000201:enzymology* / Q000473:pathology; D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D001483:Base Sequence; D018270:Carcinoma, Ductal, Breast / Q000201:enzymology* / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D046911:Macromolecular Substances; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010179:Pancreas / Q000201:enzymology; D010190:Pancreatic Neoplasms / Q000201:enzymology* / Q000473:pathology; D011510:Proteolipids / Q000096:biosynthesis*; D006180:Proton-Translocating ATPases / Q000096:biosynthesis* / Q000276:immunology; D012333:RNA, Messenger / Q000378:metabolism*; D012016:Reference Values; D014617:Vacuoles / Q000201:enzymology
D046911:Macromolecular Substances; D011510:Proteolipids; D012333:RNA, Messenger; D006180:Proton-Translocating ATPases