Polyacrylamide gel electrophoresis in human serum proteins in "normal" individuals and cancer patients.

The electrophoretic pattern of serum proteins of 100 "normal" adults and 97 non treated patients bearing different types of neoplasias were comparatively studied in polyacrylamide gel to find out if there are specific proteins or protein patterns in cancer. Densitometry was used to complete the study so as to analyze quantitative differences for each one of the regions of the arbitrarily divided electrophoregram of both types of sera. Strictly standardized colorimetric technique was used to quantify total proteins. Protein nomenclature was taken from literature data. As an average we found more bands in the cancer bearing patients than in "normal" individuals that also showed greater colour affinity in proteins. In the different regions, the main feature of neoplasia case was the presence of fewer bands in the post albumin (PA) and alpha-beta (post-beta) zones and many in 7s-globulin region (7s-g) than those found in "normals". The most important changes in the electrophoretic pattern of cancer patient serum were: a) Decrease in prealbumin (Pa), albumin (Alb), some from the postalbumin region (PA) and transferrin (T); frequent absence of ceruloplasmin (Cer) and complement factor 3 (C3) in a reduced number of cases. b) Marked increase of one alpha 1 glycoprotein in the PA region, hemopexin, haptoglobins and alpha 2-macroglobulin. Densitometry was useful to improve data obtained from visual analysis of gels but it could not make a quantitative differentiation of changes observed in beta and 7s-g regions. There was no significant difference in total protein concentration. Advantages and limitations of this method are discussed and results obtained are analyzed.