LY 379268 br Table br List of genes expressed
List of genes expressed in the MIA PaCa-2-A cells, but not in the MIA PaCa-2-R LY 379268 and whose gene ontology process includes ‘adhesion’.
Symbol Expression in MIA PaCa-2-A cells Probe_ID RefSeq_ID GI Gene Ontology process
Top 10 genes are listed in order of expression in the MIA PaCa-2-A cells.
[23,24]. The expression of CLDN in human pancreatic cancer tissue
CLDN1 has been reported to be associated with epithelial-
has been widely investigated and reported. The expression of mesenchymal transition  and the TNF-a-dependent cell
Fig. 4. Knockdown of the CLDN7 gene in the MIA PaCa-2-A cells significantly suppresses cell proliferation without altering cellular morphology. (A) The level of CLDN7 protein in the MIA PaCa-2-A cells transfected with negative control siRNA or CLDN7-specific siRNA for 48 h. CLDN7 protein level was assessed by western blot analysis. (B) The mRNA expression level of CLDN7 in the MIA PaCa-2-A cells transfected with negative control siRNA or CLDN7-specific siRNA for 48 h. The CLDN7 mRNA level was assessed by RT-PCR; *P < 0.01. (C) Transfection of the MIA PaCa-2-A cells with CLDN7-specific siRNA for 48 h significantly suppressed cell proliferation. Cell proliferation was assessed using Cell Count Reagent SF; *p < 0.01. (D) The morphology of the MIA PaCa-2-A cells was not altered following transfection with CLDN7-specific siRNA. Left panel, MIA PaCa-2-A cells transfected with negative control siRNA for 48 h; right panel, MIA PaCa-2-A cells transfected with CLDN7-specific siRNA for 48 h. (E) Cell signaling of the MIA PaCa-2-A cells transfected with negative control siRNA (lanes labled ‘a’) or CLDN7-specific siRNA (lanes labeled ‘b’).
growth  of pancreatic cancer. CLDN4 has been reported to be expressed in pancreatic cancer cell lines and human pancreatic cancer tissues , and it has been shown to be closely associated with the malignant phenotypes of pancreatic cancer . Although we demonstrated CLDN7 expression in various human pancreatic cancer cell lines, the involvement of CLDN7 in human pancreatic cancer has not yet been defined. Soini et al.  reported no as-sociation between the expression of CLDN7 and the survival of patients with pancreatic cancer, whereas Alikanoglu et al.30 demonstrated a significant association of low CLDN7 expression with shorter survival. It is likely that the CLDN family suppresses tumor cell invasion and that a low CLDN expression may promote metastasis, leading to a poor prognosis.
Results from some pre-clinical studies, however, have demon-strated different aspects of CLDN7 as regards the metastasis and proliferation of pancreatic cancer. The knockdown of the CLDN7
gene in highly metastatic pancreatic cancer in rats has been shown to markedly reduce their metastatic ability, possibly as EpCAM-associated CLDN7 inhibits EpCAM-mediated cell-cell adhesion . By cleaving EpCAM, CLDN7 supports the proliferation-promoting activity of EpCAM . In the present study, the pro-liferation of the MIA PaCa-2-A cells was markedly suppressed by the knockdown of CLDN7. It is conceivable that the EpCAM-promoted cell proliferation may be suppressed by the knockdown of CLDN7 in the MIA PaCa-2-A cells.
The significant accumulation of cells in the G1 phase indicating G1 cell cycle arrest was observed in the MIA PaCa-2-A cells trans-fected with CLDN7-specific siRNA, and this cell cycle arrest may be, at least in part, the cause of the suppression of the proliferation of the MIA PaCa-2-A cells. The association of the CLDN family with malignant phenotypes, and particularly with cell proliferation and tumor development, is complex, and the controversial