Retroviral expression screening of oncogenes in pancreatic ductal carcinoma.
Pancreatic ductal carcinoma (PDC) remains one of the most intractable malignancies in humans. In order to clarify the molecular events underlying the carcinogenesis in PDC, we constructed a retroviral cDNA expression library from a PDC cell line, and used it to screen transforming genes in PDC by a focus formation assay with mouse 3T3 fibroblasts. We could obtain a total of 30 transformed cell foci in the screening, and one of the cDNA inserts harvested from such cell clones turned out to encode a wild-type human ARAF1. Unexpectedly, a long terminal repeat-driven overexpression of ARAF1 mRNA was confirmed to induce transformed foci in fibroblasts. The oncogenic potential of ARAF1 was examined by injecting the transformed fibroblasts into athymic nude mice. Importantly, ARAF1 mRNA was highly expressed in pancreatic ductal cell specimens purified from patients with PDC. These results have unveiled the transforming potential of ARAF1 protein, and also suggest that quantity of intracellular ARAF1 may be important in carcinogenesis of various human cancers.
Kisanuki
Hiroyuki
H
Division of Functional Genomics, Jichi Medical School, 3311-1 Yakushiji, Kawachigun, Tochigi 329-0498, Japan.
Choi
Young Lim
YL
Wada
Tomoaki
T
Moriuchi
Ryozo
R
Fujiwara
Shin-Ichiro
S
Kaneda
Ruri
R
Koinuma
Koji
K
Ishikawa
Madoka
M
Takada
Shuji
S
Yamashita
Yoshihiro
Y
Mano
Hiroyuki
H
D016475:3T3 Cells; D000818:Animals; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics*; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic; D018076:DNA, Complementary / Q000235:genetics*; D015870:Gene Expression; D015723:Gene Library; D051379:Mice; D009857:Oncogenes / Q000235:genetics*; D010190:Pancreatic Neoplasms / Q000235:genetics*; D048491:Proto-Oncogene Proteins A-raf / Q000235:genetics*; D012333:RNA, Messenger; D012190:Retroviridae; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018076:DNA, Complementary; D012333:RNA, Messenger; D048491:Proto-Oncogene Proteins A-raf