Biochim Biophys Acta. 2012 Dec;1820(12):1879-85.

Calorimetry-based profiling of blood plasma from colorectal cancer patients.

Todinova S, Krumova S, Kurtev P, Dimitrov V, Djongov L, Dudunkov Z, Taneva SG.

Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria.

 

Abstract

BACKGROUND: Differential scanning calorimetry (DSC), a highly sensitive technique for resolving thermally-induced protein folding/unfolding transitions, recently was recognized as a novel tool for disease diagnosis and monitoring. To further elaborate this approach we have applied DSC in a study of blood plasma from patients with colorectal cancer (CRC) at different stages of tumor development and localization.

METHODS: Blood plasma from patients diagnosed with CRC was analyzed by DSC. The CRC thermograms were compared to those of healthy individuals and patients with gastric cancer and non-cancerous soft tissue inflammation. The thermodynamic parameters: excess heat capacity and enthalpy of the transitions corresponding to the most abundant plasma proteins, as well as transition and first moment temperatures were determined from the calorimetric profiles.

RESULTS: The calorimetric profiles of blood plasma from CRC patients are found to be distinct from those of healthy individuals and those of patients with soft tissue, non-cancerous inflammation. Generally the CRC thermograms exhibit reduced heat capacity of the major albumin/globulin-assigned thermal transitions, lower enthalpy and a featureless high temperature region compared to healthy individuals.

CONCLUSIONS: A classification of blood plasma proteome from patients with colorectal cancer (CRC1, CRC2 and CRC3 groups, and subgroups within each group CRC1(1-2), CRC2(1-2) and CRC3(1-2)) is proposed based on the derived thermodynamic parameters.

GENERAL SIGNIFICANCE: The presented data demonstrate a proof of principle and confirm that the DSC technique has a potential to monitor changes in the CRC blood plasma proteome. This study is a further step toward the validation of calorimetry as a diagnostic tool.

Copyright © 2012 Elsevier B.V. All rights reserved.

PMID: 22903026

 

SUPPLEMENT:

Calorimetry-based profiling of blood plasma/serum derived from diseased patients is recognized as a novel tool for advancing disease diagnostics and monitoring. It is based on the thermal stability of the most abundant plasma proteins and depends on their level and interactions with other molecules (specific biomarkers), hence it should reflect disease induced modifications of the plasma/serum proteome and interactome. The recorded thermogram (the thermal dependence of the excess heat capacity of the sample upon linear heating) for healthy subjects can well be described by the sum of the weighted thermograms of the most abundant plasma proteins (Garbett et al. 2009). Systematic studies of several diseases (multiple myeloma, type 1diabetes, cervical cancer, lung cancer, ovarian cancer, breast cancer, melanoma etc., as well as some premalignant states) strongly suggest a high potential of this non-invasive and label-free approach for diagnostic purposes (Garbett et al. 2009, 2013, 2014; Michnik et al. 2010; Todinova et al. 2011).

High sensitivity differential scanning calorimetry (DSC) analysis of colorectal plasma proteome revealed different thermodynamical behavior of blood plasma from patients with colorectal cancer (CRC) compared to that of healthy individuals (Figure 1). The extent of deviation of the CRC thermograms from the “standard” healthy DSC profile, evaluated on the basis of combination of Pierson coefficient and Eucledian distance parameters (Fish et al. 2010), is very strong for 78% of CRC thermograms, while slight but statistically significant for the rest 22%. The variations in the main thermal transitions (assigned to albumin and haptoglobin (Tm = 62 °C) and immunoglobulins (Tm = 70 °C)) in the CRC calorimetric profiles reflected the heterogeneity and multistage progression of the disease and allowed classification of the recorded thermograms (Figure 1). Common features for all CRC cases are higher cooperativity, lower enthalpy and featureless high temperature region (lack of the transition at 82 oC attributed to immunoglobulin G and transferrin) of the thermograms in comparison to the healthy controls.

Alhtough no correlation between the T(tumor)N(node)M(metastasis) staging and the calorimetry-based classification of CRC was evident, our data demonstrate that the tumor does induce long-lasting alteration of the plasma proteome and interactome since the thermograms of CRC patients who have undergone tumor excision (three months before recording the DSC scans) did not revert to the control profile.

Comparison of the CRC thermograms with those of a small cohort of patients with gastric cancer (GC) revealed strong similarity with two of the CRC subgroups demonstrating analogous changes in the plasma proteome for diseases similar in nature. On the other hand, the GC and CRC thermograms strongly differed from those recorded for patients with soft tissue inflammation.

The presented thermodynamic viewpoint on CRC revealed new, calorimetric signatures of this disease, probably common to other epithelial malignancies. We believe this biophysical approach might help identifying early stage malignancy in patients with persistent inflammation by regular monitoring of their plasma thermograms.

Acknowledgment:  SK was funded by World Federation of Scientists, Switzerland.

References

  1. Fish D.J., Brewood G.P., Kim J.S., Garbett N.C., Chaires J.B., Benight A.S. Biophys. Chem. 152 (2010) 184–190
  2. Garbett N.C., Mekmaysy C.S., Helm C.W., Jenson A.B., Chaires J.B. Exp. Mol. Pathol. 86 (2009) 186–191
  3. Garbett N.C., Merchant M.L., Chaires J.B., Klein J.B. Biochim. Biophys. Acta 1830 (2013) 4675–4680
  4. Garbett N.C., Merchant M.L., Helm C.W., Jenson A.B., Klein J.B., Chaires J.B. PLOS ONE 9 (2014) e84710
  5. Michnik A., Drzazga Z., Michalik K., Barczyk A., Santura I., Sozańska E., Pierzchała W. J. Therm. Anal. Calorim. 102 (2010) 57–60
  6. Todinova S., Krumova S., Gartcheva L., Robeerst C., Taneva S.G. Anal. Chem. 83 (2011) 7992–7998

 

Contact:

Stefka G. Taneva, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria

Phone: + 3592 9792625

E-mail: stefka.germanova@ehu.es (sgtaneva@gmail.com)
Fig1Figure 1. DSC thermogram of plasma proteome from healthy controls and selected CRC subgroups. Plasma proteins contributing to the main thermal transitions are indicated.

Multiselect Ultimate Query Plugin by InoPlugs Web Design Vienna | Webdesign Wien and Juwelier SchönmannMultiselect Ultimate Query Plugin by InoPlugs Web Design Vienna | Webdesign Wien and Juwelier Schönmann