[Expression of band 3 protein on erythrocytes of malignant tumor patients and its impact on proliferation of K562 cells].
OBJECTIVE
Membrane domain of band 3 protein (mdb3) mediates transmembrane exchange of chloride and bicarbonate, and regulates intracellular pH. It has been found recently that abnormality of CI(-)/HCO3(-) exchange, which mainly leads to change of intracellular pH, may be involved in cell proliferation and apoptosis. This study was to explore expression of band 3 protein on erythrocytes, and its impact on proliferation of K562 cells.


METHODS
Anion transport activity of band 3 protein on erythrocytes of 8 malignant tumor patients was measured using SPQ fluorescent probe. Expression of band 3 protein was detected by Western blot. Plasmid pYD1-mdb3 was constructed, and transfected into K562 cells. Cl- transport activity and proliferation of K562 cells were detected after transfection.


RESULTS
Of the 8 patients, 7 showed increase of anion transport activity on erythrocytes, 5 showed increase of band 3 protein expression. To some extent, expression of mdb3 enhanced proliferation of K562 cells.


CONCLUSIONS
Expression of band 3 protein is enhanced on erythrocytes of some malignant tumors, and might be a candidate marker of malignant tumors.
Bai
Shu-Zhi
SZ
Department of Pathophysiology, Harbin Medical University, Harbin, Heilongjiang, 150086, P.R.China.
Liu
Xiao-Bin
XB
Xi
Yu-Hui
YH
Wang
Tian-Ying
TY
Fu
Guo-Hui
GH
D000328:Adult; D001457:Anion Exchange Protein 1, Erythrocyte / Q000096:biosynthesis* / Q000235:genetics; D001692:Biological Transport; D049109:Cell Proliferation; D004910:Erythrocyte Membrane / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D020014:K562 Cells / Q000166:cytology / Q000378:metabolism; D009369:Neoplasms / Q000378:metabolism*; D011897:Random Allocation; D014162:Transfection
D001457:Anion Exchange Protein 1, Erythrocyte