Programmed death ligand 2 expression plays a limited role in adenocarcinomas of the gastroesophageal junction after preoperative chemotherapy.

BACKGROUND

The effects of cytotoxic chemotherapy on the expression of programmed death ligand 2 (PD-L2) are unknown and little is known about how the tumor microenvironment changes following neoadjuvant chemotherapy in locally advanced gastroesophageal adenocarcinomas (AEG). Recently, a number of studies reported that cytotoxic chemotherapy affects the expression levels of programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1). Regarding PD-L2, the second known ligand of PD‑1, no data on potential changes in expression patterns in patients with preoperatively treated AEG are available. The aim of this study was to investigate the impact of cytotoxic chemotherapy on PD-L2 expression in patients with resectable AEG.

METHODS

Consecutive patients with locally advanced AEG treated with preoperative cytotoxic chemotherapy were included. PD-L2 expression by cancer cells (CCs) and tumor-infiltrating lymphocytes (TILs) was investigated in samples of paired diagnostic biopsies and resected tumor specimens by immunohistochemistry using two different anti-PD-L2 antibodies.

RESULTS

Included were 40 patients with AEG and available paired tumor tissue samples. PD-L2 expression was observed in one diagnostic biopsy sample by CCs and in one diagnostic biopsy sample by TILs. There was no difference concerning the expression levels measured by the two antibodies.

CONCLUSION

In contrast to previously published studies reporting PD-L2 expression rates of up to 50% in AEGs, in our cohort, PD-L2 expression seems to play no significant role in AEG.

Informations de copyright

© The Author(s) 2021.

Déclaration de conflit d'intérêts

Conflict of interestThis study was partially supported by the Promedica Stiftung (1406/M and 1412/M), the Swiss Cancer Research Foundation (KFS-4243-08-2017), the Swiss National Science Foundation (PMPDP3_151326), the Clinical Research Priority Program (CRPP) of the University of Zurich, and the European Academy of Dermatology and Venereology (PPRC-2019-20). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. A. Ilhan-Mutlu participated in advisory boards from MSD, BMS, and Servier; received lecture honoraria from Eli Lilly, MSD, and Servier; is the local PI for clinical trials sponsored by BMS and Roche; and received travel support from BMS, Roche, and Servier. M. Preusser has received honoraria for lectures, consultation, or advisory board participation from the following for-profit companies: Bayer, Bristol-Myers Squibb, Novartis, Gerson Lehrman Group (GLG), CMC Contrast, GlaxoSmithKline, Mundipharma, Roche, BMJ Journals, MedMedia, Astra Zeneca, AbbVie, Lilly, Medahead, Daiichi Sankyo, Sanofi, Merck Sharp & Dome, Tocagen, Adastra. G. Jomrich, D. Kollmann, L. Wilfing, S. Radosavljevic, D. Ramazanova, R. Ristl, R.P. Grose, C. Fassnacht, Y.-C. Tsai, E. Guenova, and S.F. Schoppmann declare that they have no competing interests.