Authors: NaMi Cho D James Morré
Publish Date: 2008/08/15
Volume: 58, Issue: 4, Pages: 547-552
Abstract
Full length mRNA to a druginhibited cell surface NADH oxidase tNOX or ENOX2 is present in both noncancer and cancer cells but is translated only in cancer cells as alternatively spliced variants ENOX2 is a growthrelated protein of the external plasma membrane surface that is shed into the circulation and is inhibited by a series of quinone site inhibitors with anticancer activity To test the possibility that ENOX2 expression might be important to early stages of noncancer cell development the expression of the protein was monitored in chicken embryos during their development Polyclonal antisera to a 34 kDa human serum form of ENOX2 crossimmunoreactive with the drugresponsive NADH oxidase of chicken hepatoma cells was used The protein was identified based on drugresponsive enzymatic activities and analyses by western blots The drugresponsive activity was associated with plasma membranes and sera of early chicken embryos and with chicken hepatoma plasma membranes but was absent from plasma membranes prepared from livers or from sera of normal adult chickens and from late embryo stages The findings suggest that ENOX2 may fulfill some functions essential to the growth of early embryos which are lost in late embryo stages and absent from normal adult cells but which then reappear in cancer
Keywords: