TY - JOUR
T1 - Altered expression of annexin II in human B-cell lymphoma cell lines
AU - Chiang, Yungping
AU - Davis, Randall G.
AU - Vishwanatha, Jamboor K.
N1 - Funding Information:
We thank Drs. Samuel Piruccello, Shantaram Joshi and Helen Evans for cell lines, and Drs. Blake Pepinsky and Tony Hunter for the anti-annexin II antisera. This research was supported by funds from the National Institutes of Health (GM46459) and University of Nebraska Medical Center (Seed Grant and Translational Grant programs).
PY - 1996/10/11
Y1 - 1996/10/11
N2 - Annexin II is a growth-regulated gene, whose expression is significantly increased in various human cancers. We examined annexin II expression in 11 human B-cell lymphoma cell lines and in normal B-cells. Wide variation was observed in the levels of annexin II in these cell lines. Annexin II overexpression was observed in 5 cell lines, while significantly reduced expression was observed in Raji, OMA-BL-1 and REH cell lines. Analysis of the annexin II gene, mRNA and protein in Raji and OMA-BL-1 cell lines indicated that annexin II gene was unaltered and that a low level of annexin If transcripts are produced in these cells. Down-regulation of annexin II expression was at the transcriptional level, and no reexpression of annexin II was observed after treatment of cells with demethylating agents. Thus methylation of the annexin II gene does not appear to be responsible for annexin II down-regulation. A slow migrating altered form of annexin II was detected in Raji and OMA-BL-1 cells, which was detected with the anti-chicken annexin II antiserum, but not with the anti-human annexin II antiserum. The slow migrating annexin II species was found to be sensitive to dephosphorylation by calf intestinal alkaline phosphatase, resulting in reduction of the size of the protein on SDS-polyacrylamide gels. The phosphorylated annexin II was also observed in nuclear extracts of human K562 and HeLa cells. Thus, Raji and OMA-BL-1 cells exclusively produce a phosphorylated form of annexin II, and phosphorylated annexin II may be important for cell survival and proliferation.
AB - Annexin II is a growth-regulated gene, whose expression is significantly increased in various human cancers. We examined annexin II expression in 11 human B-cell lymphoma cell lines and in normal B-cells. Wide variation was observed in the levels of annexin II in these cell lines. Annexin II overexpression was observed in 5 cell lines, while significantly reduced expression was observed in Raji, OMA-BL-1 and REH cell lines. Analysis of the annexin II gene, mRNA and protein in Raji and OMA-BL-1 cell lines indicated that annexin II gene was unaltered and that a low level of annexin If transcripts are produced in these cells. Down-regulation of annexin II expression was at the transcriptional level, and no reexpression of annexin II was observed after treatment of cells with demethylating agents. Thus methylation of the annexin II gene does not appear to be responsible for annexin II down-regulation. A slow migrating altered form of annexin II was detected in Raji and OMA-BL-1 cells, which was detected with the anti-chicken annexin II antiserum, but not with the anti-human annexin II antiserum. The slow migrating annexin II species was found to be sensitive to dephosphorylation by calf intestinal alkaline phosphatase, resulting in reduction of the size of the protein on SDS-polyacrylamide gels. The phosphorylated annexin II was also observed in nuclear extracts of human K562 and HeLa cells. Thus, Raji and OMA-BL-1 cells exclusively produce a phosphorylated form of annexin II, and phosphorylated annexin II may be important for cell survival and proliferation.
KW - Annexin II
KW - B-cell lymphoma
KW - Cell proliferation
KW - DNA replication
KW - Phosphorylation
UR - http://www.scopus.com/inward/record.url?scp=0030580097&partnerID=8YFLogxK
U2 - 10.1016/0167-4889(96)00103-6
DO - 10.1016/0167-4889(96)00103-6
M3 - Article
C2 - 8898868
AN - SCOPUS:0030580097
SN - 0167-4889
VL - 1313
SP - 295
EP - 301
JO - BBA - Molecular Cell Research
JF - BBA - Molecular Cell Research
IS - 3
ER -