MALDI-Imaging – a tool for proteomic characterization of tumor cells

Introduction:

Matrix assisted laser desorption/ionization (MALDI) imaging is a recently developed molecular imaging method. It simultaneously reveals the label-free detection of numerous molecules in-vitro. In this study, the method is used in an exemplary way to obtain molecular characterization of oropharyngeal cancer tissue and fine-needle aspiration cytology (FNAC).

Methods:

From 20 patients with SCC located in the oropharynx, both FNAC and tissue samples from the primary tumor zone as well as from the adjacent normal tissue zones were used. Tissue sections and cell aspirates were placed on glass slides. After sample specific processing the sections and the cells were analyzed with MALDI imaging. Afterwards the MALDI data were compared with histological and cytological staining. Identification of potential tumor marker was carried out with liquid chromatography-mass spectrometry (LC-MS/MS).

Results:

The assessment of the MALDI data of the tissues resulted in proteomic signatures specific to SCC allowing a clear differentiation between malign and benign tissue areas. Different, already established as well as new potential marker proteins could identified. The transfer of these data onto the aspirates leads to new approaches in the diagnostic of FNAC.

Conclusions:

MALDI imaging is an appropriate tool for the comprehensive molecular characterization of tumor tissue and tumor cells of the head and neck area. The signatures can contribute to improved diagnostics of oropharyngeal carcinoma. In combination with further examinations, they can provide valuable information regarding the inhomogeneous therapy response and contribute to a better understanding of the tumor biology.

Publication History

Publication Date:
23 April 2019 (online)