PD-L1 and Notch as novel biomarkers in pancreatic sarcomatoid carcinoma: a pilot study
Nicola Silvestris, Antonella Argentiero, Oronzo Brunetti, Margherita Sonnessa, Fulvia Colonna, Sabina Delcuratolo, Claudio Luchini, Aldo Scarpa, Sara Lonardi, Floriana Nappo, Matteo Fassan, Antonio Giovanni Solimando, Livia Fucci, Concetta Saponaro
Abstract
BACKGROUND: The improved immunological understanding revealed the tumor microenvironment as an appealing driver to restore the immune response against cancer cells resulting in a paradigm shift in the oncology field. However, the complexity of the tumor milieu suggests the role of several pathways linking in immunomodulation mechanisms. Pancreatic cancer represents a model of the intricate relationship between malignant cells and their surrounding neighborhood. RESEARCH DESIGN AND METHODS: In this study, we analyzed, retrospectively, six cases of rare pancreatic sarcomatoid carcinoma (PSC) and evaluated the expression of PD-L1 and Notch, aiming to explore new attributes in immunophenotype. RESULTS: PD-L1 CPS ≥ 1was common in PSCs (83%) with half samples expressing PD-L1 CPS ≥ 50. Notch1 and Notch3 demonstrated a high range of expression. A direct significant correlation between PD-L1 and Notch3 overexpression (r = 0.7; p = 0.036) has been observed. Immunofluorescence studies revealed a co-localization of Notch3 and PD-L1 when both proteins were over-expressed within cytoplasmic or membranous compartments of the same cells. CONCLUSIONS: Our data identify a unique biological characterization of this rare pancreatic histotype. These findings provide a rationale for future studies evaluating the potential crosstalk between PD-L1/PD-1 axis and Notch pathways and prompting the development of novel therapeutics strategy.