Esophageal and gastric cancers represent tumors with poor prognosis. Unfortunately, radiotherapy, chemotherapy, and targeted therapy have made only limited progress in recent years in improving the generally disappointing outcome. Immunotherapy with checkpoint inhibitors is a novel treatment approach that quickly entered clinical practice in malignant melanoma and renal cell cancer, but the role in esophageal and gastric cancer is still poorly defined. The principal prognostic/predictive biomarkers for immunotherapy efficacy currently considered are PD-L1 expression along with defects in mismatch repair genes resulting in microsatellite instability (MSI-H) phenotype. The new molecular classification of gastric cancer also takes these factors into consideration. Available reports regarding PD-1, PD-L1, PD-L2 expression and MSI status in gastric and esophageal cancer are reviewed to summarize the clinical prognostic and predictive role together with potential clinical implications. The most important recently published clinical trials evaluating checkpoint inhibitor efficacy in these tumors are also summarized.

• Klíčová slova
• checkpoint inhibitors, esophageal cancer, gastric cancer, immunotherapy, microsatellite instability,
• MeSH
• antigeny CD273 metabolismus   MeSH
• antigeny CD274 metabolismus   MeSH
• antigeny CD279 metabolismus   MeSH
• epitelo-mezenchymální tranzice MeSH
• exprese genu MeSH
• fenotyp MeSH
• imunita * MeSH
• imunoterapie * metody   MeSH
• kombinovaná terapie MeSH
• lidé MeSH
• mikrosatelitní nestabilita MeSH
• mikrosatelitní repetice MeSH
• nádory jícnu diagnóza   genetika   imunologie   terapie   MeSH
• nádory žaludku diagnóza   genetika   imunologie   terapie   MeSH
• únik nádoru z imunitní kontroly imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• antigeny CD273 MeSH
• antigeny CD274 MeSH
• antigeny CD279 MeSH

The prognosis of esophageal cancer (EC) is poor, despite considerable effort of both experimental scientists and clinicians. The tri-modality treatment consisting of neoadjuvant chemoradiation followed by surgery has remained the gold standard over decades, unfortunately, without significant progress in recent years. Suitable prognostic factors indicating which patients will benefit from this tri-modality treatment are missing. Some patients rapidly progress on the neoadjuvant chemoradiotherapy, which is thus useless and sometimes even harmful. At the same time, other patients achieve complete remission on neoadjuvant chemoradiotherapy and subsequent surgery may increase their risk of morbidity and mortality. The prognosis of patients ranges from excellent to extremely poor. Considering these differences, the role of drug metabolizing enzymes and transporters, among other factors, in the EC response to chemotherapy may be more important compared, for example, with pancreatic cancer where all patients progress on chemotherapy regardless of the treatment or disease stage. This review surveys published literature describing the potential role of ATP-binding cassette transporters, the genetic polymorphisms, epigenetic regulations, and phenotypic changes in the prognosis and therapy of EC. The review provides knowledge base for further research of potential predictive biomarkers that will allow the stratification of patients into defined groups for optimal therapeutic outcome.

• Klíčová slova
• ABC transporters, biomarker, cancer, chemotherapy, esophagus, prognosis, radiotherapy,
• MeSH
• ABC transportéry genetika   metabolismus   MeSH
• epigeneze genetická MeSH
• lidé MeSH
• nádorové biomarkery genetika   metabolismus   MeSH
• nádory jícnu genetika   metabolismus   terapie   MeSH
• neoadjuvantní terapie metody   MeSH
• polymorfismus genetický MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• ABC transportéry MeSH
• nádorové biomarkery MeSH