Characterization of zinc-α2-glycoprotein as a cell adhesion molecule that inhibits the proliferation of an oral tumor cell line
✍ Scribed by Gang Lei; Henry Brysk; Istvan Arany; Stephen K. Tyring; Ganesan Srinivasan; Miriam M. Brysk
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 203 KB
- Volume
- 75
- Category
- Article
- ISSN
- 0730-2312
No coin nor oath required. For personal study only.
✦ Synopsis
Zn-␣ 2 -glycoprotein (Zn␣ 2 gp) is a soluble protein widely distributed in body fluids and glandular epithelia. We have found it to be expressed in stratified epithelia as well. Zn␣ 2 gp is clinically correlated with differentiation in various epithelial tumors, including oral and epidermal tumors. We have cloned epidermal Zn␣ 2 gp and report the preparation of the recombinant protein in a Baculovirus expression system. Like the native molecule, recombinant Zn␣ 2 gp has RNase activity. Zn␣ 2 gp functions as a matrix protein for the Tu-138 oral squamous cell carcinoma cell line. Cell attachment to Zn␣ 2 gp is comparable to that for fibronectin and is inhibited by the synthetic RGD peptides RGD, RGDV, and RGDS. Attachment is also inhibited by the antibody to integrin ␣ 5  1 (the fibronectin receptor), but not by antibodies to integrins ␣ v  3 , ␣ 3  1 , and ␣ 2  1 . We find that the proliferation of Tu-138 cells is inhibited on a Zn␣ 2 gp matrix, as compared with other matrix proteins (fibronectin, vitronectin, laminin, and collagens I and IV) on which growth resembles that on the BSA control. We believe that the role of Zn␣ 2 gp in differentiation and its RNase activity are two likely suspects as agents of the inhibition of proliferation.