title: Differential scanning calorimetry of gliomas: a new tool in brain cancer diagnostics?
abstract: BACKGROUND
  Thermal stability signatures of complex molecular interactions in biological fluids can be measured using differential scanning calorimetry (DSC). Evaluating the thermal stability of plasma proteomes offers a method of producing a disease-specific "signature" (thermogram) in neoplastic and autoimmune diseases.
  
  
  OBJECTIVE
  The authors describe the use of DSC with human brain tumor tissue to create unique thermograms for correlation with histological tumor classification.
  
  
  METHODS
  Primary brain tumors were classified according to the World Health Organization classification. Tumor samples were digested and assayed by a DSC calorimeter. Experimental thermograms were background subtracted and normalized to the total area of transitions to exclude concentration effects. The resulting thermograms were analyzed by applying 2-state, scaled, Gaussian distributions.
  
  
  RESULTS
  Differences in glioma-specific signatures are described by using calculated parameters at transitions that are characterized, in the equilibrium approximation, by a melting temperature (Tm), an apparent enthalpy change (ΔH), and a scaling factor related to the relative abundance of the materials denatured in the transition (Aw). Thermogram signatures of glioblastoma multiforme and low-grade astrocytomas were differentiated by calculated values of Aw3 and Tm4, those of glioblastoma multiforme and oligodendrogliomas were differentiated by Aw2, ΔH2, ΔH4, and Tm4, and those of low-grade astrocytomas and oligodendroglioma were differentiated by Aw4.
  
  
  CONCLUSIONS
  Our preliminary results suggest that solid brain tumors exhibit specific thermogram profiles that are distinguishable among glioma grades. We anticipate that our results will form the conceptual base of a novel diagnostic assay based on tissue thermograms as a complement to currently used histological analysis.
authors.affiliation: ‡Department of Neurosurgery, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah; ¶TA Instruments, Inc, Lindon, Utah; §Department of Chemistry, Brigham Young University, Provo, Utah.
authors.forename: Alexis A
authors.initials: AA
authors.lastname: Chagovetz
authors.forename: Colette
authors.initials: C
authors.lastname: Quinn
authors.forename: Neil
authors.initials: N
authors.lastname: Damarse
authors.forename: Lee D
authors.initials: LD
authors.lastname: Hansen
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Chagovetz
authors.forename: Randy L
authors.initials: RL
authors.lastname: Jensen
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000145:classification* / Q000473:pathology*; D002152:Calorimetry, Differential Scanning / Q000379:methods*; D005260:Female; D005910:Glioma / Q000145:classification* / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D055815:Young Adult