Figure 1.
(A) Thyroid papillary cancer tissue was localized on the left, and normal thyroid tissue was localized on the right (original magnification 40×). The stromal region was excluded. The ROI was determined from the corresponding HE-staining results. The black boxes indicate the representative region of cancer and normal thyroid tissue. (B) Magnified representative regions of cancer and normal tissue (original magnification 200×). The cancer cells had a high cytoplasmic ratio and displayed nuclear features characteristic of papillary thyroid cancer. Histologic findings of thyroid papillary cancer consisted of columnar thyroidal epithelium set in papillary projection. The normal thyroid tissue is composed of many spherical hollow sacs called thyroid follicles.
Figure 2.
(A) Spectrum of the cancer region and (B) spectrum of normal region. Each spectrum was averaged from the ROI of cancer and normal tissue in Figure 1. Each number shown in Table 1 was assigned using these spectra.
Table 1.
Peak picking and statistical analysis of mass spectra in case 1.
Figure 3.
Visualization of molecular distribution in case 1.
We visualized ion images corresponding to the results shown in Table 1. In all images, the cancer tissue is on the left and normal tissue is on the right. The distribution of the intensity for each m/z value was not constant in the cancer and normal thyroid tissue.
Table 2.
Overview of the m/z values that had higher expression levels in cancer regions of all cases.
Figure 4.
Visualization of molecular distribution of m/z values that were expressed to higher levels in cancer tissue from all cases.
The ROI of each case is defined by a dashed line in HE-staining images. The intensity of all values in the cancer region was higher than in normal regions. The distribution of intensity in m/z 741.5 was different from the distribution of intensity in the other m/z values.
Figure 5.
(A) MS/MS data of m/z 798.5. The structure of one peak was analyzed. The product ion spectrum of m/z 798.5 as a precursor ion was obtained by MS/MS of thyroid papillary cancer region. This biomolecule was identified by neutral loss as [PC (16:0/18:1)+K]+. In the same manner, in (B) m/z 796.5 was identified as [PC (16:0/18:2)+K]+. (C) m/z 741.5 was identified as [SM (d18:0/16:1)+K]+.