Figure 3

A representative analysis of a histological thin section from an ovarian carcinoma sample by MALDI tissue imaging mass spectrometry (MALDI TIMS). (A) A thin section (10 μm) with H & E staining. Regions distinguished by "a" were histologically identified as non-malignant stroma, "b" as serous papillary epithelial carcinoma, and "*" are regions where there were no cells. The spots represent the sites where the MALDI TIMS spectra were collected (i.e., each spot represents the region targeted by the laser to generate one spectrum) with the regions histologically scored as serous papillary epithelial carcinoma in black; blue spots were from regions scored as stromal cells; the red dots are regions where there were no cells or the histology was undefined. (B and C) Spectra obtained from the shown regions of the adjacent thin section (10 μm). (D) Ion intensities of the m/z 778.6 (d18:1/C16:0 ST) species from regions scored as normal (n = 23) or ovarian cancer (n = 20) (P = 0.00003, by one-tailed Wilcoxon rank sum test).