title: Assessment of protein conformation in human benign and malignant astrocytomas by reflectance Fourier transform infrared microspectroscopy.
abstract: The secondary structure and composition of protein in the tissues of benign and malignant astrocytomas were determined by reflectance Fourier-transform infrared (FT-IR) microspectroscopy. The peak maximum of IR spectra of the tissues from recurrent malignant astrocytoma markedly appeared at higher frequency (1655 or 1663 cm(-1)), which was significantly different from that of the tissues from benign astrocytoma at 1651 cm(-1) and tissues from malignant astrocytoma at 1652 cm(-1). Malignant astrocytoma indicated slightly different compositions in the protein secondary structure from benign astrocytoma. However, a significant increase in beta-turn structure but a marked decrease in beta-sheet and random coil structures were observed in the protein secondary structure of the recurrent malignant astrocytoma. The phenomenon was more pronounced in recurrent malignant astrocytoma pretreated with radiation and chemotherapy. The rapid cell proliferation and cell differentiation of malignant astrocytoma with or without recurrence might be the possible explanations for the different compositions of protein conformational structures.
authors.affiliation: Neurological Institute, Veterans General Hospital-Taipei, Taiwan, Republic of China.
authors.forename: L S
authors.initials: LS
authors.lastname: Lee
authors.forename: C W
authors.initials: CW
authors.lastname: Chi
authors.forename: H C
authors.initials: HC
authors.lastname: Liu
authors.forename: C L
authors.initials: CL
authors.lastname: Cheng
authors.forename: M J
authors.initials: MJ
authors.lastname: Li
authors.forename: S Y
authors.initials: SY
authors.lastname: Lin
mesh_terms: D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000737:chemistry* / Q000473:pathology*; D001932:Brain Neoplasms / Q000737:chemistry* / Q000473:pathology*; D002648:Child; D005260:Female; D005909:Glioblastoma / Q000737:chemistry / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000737:chemistry*; D017433:Protein Structure, Secondary; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods
chemical_list: D009363:Neoplasm Proteins