Following exposure to biological fluids (e.g., serum, plasma, cerebral spinal fluid), nanoparticles (NPs) interact with thousands of different biomolecules such as human plasma (HP) proteins, lipids and sugars, which adsorb on their surface and form an outer layer referred to as "protein corona" (PC). Noteworthy, these PC surrounding nanomaterials do not merely reflect the composition of the human proteome, but they mostly depend on its alterations. This may be relevant for early cancer detection where changes in the abundance of typical biomarkers are the hallmark of several types of cancer since the human proteome evolves as the disease progresses. Recent advances in nanotechnology have demonstrated that exposing nanomaterials to HP obtained from healthy subjects and patients with various diseases, induced considerable alterations in the corona profile of NPs. Thus, nanomaterials incubated with plasma proteins of individuals with different physiological conditions generate PCs with different compositions. Among nanomaterials under development for in vitro diagnostic testing, Graphene Oxide (GO) is regarded as one of the most promising ones due to its intrinsic properties and peculiar behaviour in biological environments. By taking advantage of these considerations, in the proposed project, we aim to develop an innovative PC-based blood test for early cancer detection based on the characterization of the PC that forms around GO nanoflakes. The proposed approach rely on the overall evaluation of the protein pattern by means of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE).We envision that a systematic investigation of a PC-based technology may improve our knowledge of several cancer biology and may offer new opportunities for cancer detection and biomarkers identification.
To date, there are no economic and minimally invasive tools allowing large-scale screening for several cancer types. Since the graphene oxide-protein corona (GO-PC) composition show to be strongly affected by the pathological conditions of the biological source[1], we aim to develop an innovative diagnostic tool. As a matter of fact, currently in the oncological diagnostic research, the identification of alterations in the blood is limited to high-resolution proteomics techniques. Among these, mass spectrometry is the most widely used as it is characterized by a high specificity and selectivity in the separation and identification of individual biomarkers [2,3]. Nevertheless, the limit of this technique lies in the high cost and laborious procedures that must be developed for each experiment. On the other side, the emerging PC-based technology depends on non-invasive and cheap tools. The molecular composition of the PC formed around nanoparticles (NPs) could change in healthy and unhealthy donors¿ blood and one-dimensional electrophoretic gel (1D SDS-PAGE) can reveal such differences. However, these alterations are often small, difficult to be detected and make the search continues for new biomarkers challenging. Thus, the choice of the NP formulation, standardization of the experimental protocols and the employment of highly manageable and inexpensive experimental devices may really make the difference in this field. In this project we will employ GO to generate a blood test based on PC characterisation for early cancer detection by incubating graphene oxide nanoflakes with plasma samples derived from healthy volunteers and cancer diagnosed ones. GO boasts of low-cost production, dispersibility in water solvents, the high surface area high reactivity for linking proteins. One of its advantages is the lower affinity that its surface has for albumin [4], the most abundant blood protein. On the other hand, its peculiarity relies on the preferential affinity that it has towards the low-abundance plasma proteins. This characteristic behaviour makes GO act as a ¿nano-concentrator¿ favoring a more sensitive differentiation between individual donor classes. Indeed, the exposure of GO to plasma derived from unhealthy donors significantly affects the composition of GO-PC complexes. We aim to exploit the high adsorption ability of GO NPs to improve resolution and accuracy of the protein patterns associated to different classes of tumors. As a result, we predict that a systematic investigation of GO-PC may lay the foundation to a straightforward diagnostic approach for cancer that exploits the potentiality of the PC modulation. The improvements in the characterization of the PC using a technology based on simple and non-invasive tool would boost clinical application and develop more sensitive and sensible test.
[1] Papi, M. et al., Nanoscale (2019), 11(32), 15339-15346
[2] J.D. Wulfkuhle et al., Nature reviews cancer (2003), 3(4), 267-275
[3] Digiacomo, L. et al., J. Nanotheranostics (2021), 2(2), 82-93
[4] M. Sopotnik et al., Carbon (2015), 95, 560-572