Applying Probe Electrospray Ionization Mass Spectrometry to Cytological Diagnosis: A Preliminary Study by Using Cultured Lung Cancer Cells

Acta Cytol. 2021;65(5):430-439. doi: 10.1159/000516639. Epub 2021 Jun 7.

Abstract

Objectives: Cytology and histology are 2 indispensable diagnostic tools for cancer diagnosis, which are rapidly increasing in importance with aging populations. We applied mass spectrometry (MS) as a rapid approach for swiftly acquiring nonmorphological information of interested cells. Conventional MS, which primarily rely on promoting ionization by pre-applying a matrix to cells, has the drawback of time-consuming both on data acquisition and analysis. As an emerging method, probe electrospray ionization-MS (PESI-MS) with a dedicated probe is capable to pierce sample and measure specimen in small amounts, either liquid or solid, without the requirement for sample pretreatment. Furthermore, PESI-MS is timesaving compared to the conventional MS. Herein, we investigated the capability of PESI-MS to characterize the cell types derived from the respiratory tract of human tissues.

Study design: PESI-MS analyses with DPiMS-2020 were performed on various type of cultured cells including 5 lung squamous cell carcinomas, 5 lung adenocarcinomas, 5 small-cell carcinomas, 4 malignant mesotheliomas, and 2 normal controls.

Results: Several characteristic peaks were detected at around m/z 200 and 800 that were common in all samples. As expected, partial least squares-discriminant analysis of PESI-MS data distinguished the cancer cell types from normal control cells. Moreover, distinct clusters divided squamous cell carcinoma from adenocarcinoma.

Conclusion: PESI-MS presented a promising potential as a novel diagnostic modality for swiftly acquiring specific cytological information.

Keywords: Lung cytopathology; Mass spectrometry; Probe electrospray ionization mass spectrometry; Rapid cytological diagnosis.

MeSH terms

  • Cell Culture Techniques / methods
  • Cells, Cultured / pathology*
  • Cytodiagnosis* / methods
  • Humans
  • Lung Neoplasms / pathology*
  • Mass Spectrometry / methods
  • Spectrometry, Mass, Electrospray Ionization* / methods