Plasma protein profiling of breast cancer patients of North Indian population: A potential approach to early detection

Abstract

Study background: Over the last two decades worldwide the mortality due to breast cancer (BC) raises catastrophically. Unfortunately, clinicians are still seeking for reliable resources for early speculations. Recently, the approach of investigative plasma based molecular markers builds a new hope for the early stage diseases. Methods: Blood samples of healthy and BC individuals from North Indian women (n=25) were collected. In order to increase the detecting sensitivity of protein of interest, the pooled plasma samples were subjected to Multiple affinity removal system (MARS) Hu-14 and PROTEOPREP 20 and further processed by 2D-PAGE/LCMS/ MS analysis. Finally, the levels of selected proteins were independently estimated by western blotting and immunohistochemistry. Results: The comparative 1D-SDS page and 2DE gel analysis showed the high proficiency of Hu-14 MARS for diminution of HAPs. The proteome profile of pooled plasma sample yielded total 24 differentially expressed spots in BC over control. Among them, the identified 3 up-regulated proteins, Serpin peptidase inhibitor clade A (privilege 92%; 95%CI 79.36-104.63), Apolipoprotein A IV (privilege 72%; 95%CI 52.4-91.6), Apolipoprotein AI (privilege 92%; 95%CI 79.36-104.63), and 1 down-regulated α-2-HS glycoprotein (privilege 76%; 95%CI 57.26-94.74) spots were of high significance (p<0.05). These proteins are involved in pathogenesis of cancer and play an important role in the regulation of metastasis. However their discerned molecular mechanisms evaluation related to BC is ongoing to scrutinize its clinical utility. Importantly, the results of immunochemical quantifications were found consistent with the changes in 2-DE check for all candidates apart from α-2-HS glycoprotein, where the immunohistochemistry analysis was not correlated well with 2DE and immunoblotting. Conclusion: This preliminary work presents a panel of differential plasma proteins in BC patients, validated by combining routine clinical immunochemical reactions for the first time in North India. Further, in order to establish a cause and effect relationship of these highly modulated proteins with BC needs large scale sample size investigation. © 2013 Arora D, et al.