title: Monitoring of chemotherapy leukemia treatment using Raman spectroscopy and principal component analysis.
abstract: In this research, we used the Raman spectroscopy to distinguish between normal and leukemia blood serum and identify the different types of leukemia based on serum biochemistry. In addition, monitoring of patients under chemotherapy leukemia treatment (CHLT) was studied. Blood samples were obtained from seven patients who were clinically diagnosed with three leukemia types and 21 healthy volunteers. In addition, other five leukemia patients were monitored during the CHLT, two patients were declared healthy, one patient suspended it; the health of the other two patients worsened, and no improvement was observed along CHLT. The serum samples were put under an Olympus microscope integrated to the Raman system, and several points were chosen for the Raman measurement. The Horiba Jobin Yvon LabRAM HR800 Raman system is equipped with a liquid nitrogen-cooled detector and a laser of 830 nm with a power irradiation of 17 mW. It is shown that the serum samples from patient with leukemia and from the control group can be discriminated when multivariate statistical methods of principal component analysis (PCA) and linear discriminant analysis (LDA) are applied to their Raman spectra obtaining two large clusters corresponding to the control and leukemia serum samples and three clusters inside the leukemia group associated with the three leukemia types. The major differences between leukemia and control spectra were at 1,338 (Trp, α-helix, phospholipids), 1,447 (lipids), 1,523 (β-carotene), 1,556 (Trp), 1,587 (protein, Tyr), 1,603 (Tyr, Phe), and 1,654 (proteins, amide I, α-helix, phospholipids) cm(-1), where these peaks were less intense in the leukemia spectrum. Minor differences occurred at 661 (glutathione), 890 (glutathione), 973 (glucosamine), 1,126 (protein, phospholipid C-C str), 1,160 (β-carotene), 1,174 (Trp, Phe), 1,208 (Trp), 1,246 (amide III), 1,380 (glucosamine), and 1,404 (glutathione) cm(-1). Leukemia spectrum showed a peak at 917 cm(-1) associated with glutathione, but it was absent in the control spectrum. The results suggest that the Raman spectroscopy and PCA could be a technique with a strong potential of support for current techniques to detect and identify the different leukemia types by using a serum sample. Nevertheless, with the construction of a data library integrated with a large number of leukemia and control Raman spectra obtained from a wide range of healthy and leukemic population, the Raman-PCA technique could be converted into a new technique for minimally invasive real-time diagnosis of leukemia from serum samples. In addition, complementary results suggest that using these techniques is possible to monitor CHLT.
authors.affiliation: Biophysics and Biomedical Sciences Laboratory, Centro Universitario de los Lagos, Universidad de Guadalajara, Enrique Díaz de León 1144, Paseo de la Montaña, CP 47460, Lagos de Moreno, Jalisco, México, jluis0968@gmail.com.
authors.forename: José Luis
authors.initials: JL
authors.lastname: González-Solís
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Martínez-Espinosa
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: Salgado-Román
authors.forename: Pascual
authors.initials: P
authors.lastname: Palomares-Anda
mesh_terms: D000293:Adolescent; D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002648:Child; D016002:Discriminant Analysis; D016903:Drug Monitoring; D006801:Humans; D007938:Leukemia / Q000175:diagnosis / Q000188:drug therapy*; D008875:Middle Aged; D025341:Principal Component Analysis; D013059:Spectrum Analysis, Raman / Q000379:methods*; D055815:Young Adult
chemical_list: D000970:Antineoplastic Agents