title: Imaging mass spectrometry distinguished the cancer and stromal regions of oral squamous cell carcinoma by visualizing phosphatidylcholine (16:0/16:1) and phosphatidylcholine (18:1/20:4).
abstract: Most oral cancers are oral squamous cell carcinoma (OSCC). The anatomical features of OSCC have been histochemically evaluated with hematoxylin and eosin. However, the border between the cancer and stromal regions is unclear and large portions of the cancer and stromal regions are resected in surgery. To reduce the resected area and maintain oral function, a new method of diagnosis is needed. In this study, we tried to clearly distinguish the border on the basis of biomolecule distributions visualized by imaging mass spectrometry (IMS). In the IMS dataset, eleven signals were significantly different in intensity (p < 0.01) between the cancer and stromal regions. Two signals at m/z 770.5 and m/z 846.6 were distributed in each region, and a clear border was revealed. Tandem mass spectrometric (MS/MS) analysis identified these signals as phosphatidylcholine (PC) (16:0/16:1) at m/z 770.5 in the cancer region and PC (18:1/20:4) at m/z 846.6 in the stromal region. Moreover, the distribution of PC species containing arachidonic acid in the stromal region suggests that lymphocytes accumulated in response to the inflammation caused by cancer invasion. In conclusion, the cancer and stromal regions of OSCCs were clearly distinguished by use of these PC species and IMS analysis, and this molecular identification can provide important information to elucidate the mechanism of cancer invasion.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Uchiyama
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hayasaka
authors.forename: Noritaka
authors.initials: N
authors.lastname: Masaki
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Kazuma
authors.initials: K
authors.lastname: Masumoto
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Nagata
authors.forename: Fuminori
authors.initials: F
authors.lastname: Katou
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Setou
mesh_terms: D016718:Arachidonic Acid / Q000032:analysis / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000737:chemistry / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D003952:Diagnostic Imaging / Q000379:methods*; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin; D006801:Humans; D008214:Lymphocytes / Q000473:pathology; D008867:Microtomy; D009062:Mouth Neoplasms / Q000737:chemistry / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D009928:Organ Specificity; D019308:Palmitic Acid / Q000032:analysis / Q000378:metabolism; D010713:Phosphatidylcholines / Q000032:analysis* / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D016610:Tissue Embedding; D059016:Tumor Microenvironment
chemical_list: D010713:Phosphatidylcholines; D016718:Arachidonic Acid; D019308:Palmitic Acid; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin