Immunohistochemical Profiling of IDO1 and IL4I1 in Head and Neck Squamous Cell Carcinoma: Interplay for Metabolic
Benedikt Schmidl1, Maren Lauterbach1, Fabian Stögbauer2
1Department of Otolaryngology Head and Neck Surgery, Technical University Munich, 81675 Munich, Germany.
Abstract:
Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous and malignant disease with a limited number of biomarkers and insufficient targeted therapies. The current therapeutic landscape is challenged by low response rates, underscoring the need for new therapeutic targets. The success of immunotherapy in HNSCC has highlighted the importance of the immune microenvironment, and since metabolic reprogramming, especially altered tryptophan metabolism, is an important aspect in immune evasion, the interplay of the two enzymes IDO1 and IL4I1 was investigated in HNSCC to assess their immunosuppressive roles and potential as prognostic biomarkers. The immunohistochemical expression of IDO1 and IL4I1 was evaluated by an experienced head and neck pathologist in a tissue microarray (TMA) of 402 patients with HNSCC. Clinical and pathological data were retrieved, and the overall survival of the patients was calculated. In this study, IDO1 and IL4I1 were expressed by HNSCC tumor cells in the TMA of 402 patients. The overall survival analysis of the clinical data of the patients revealed that high IL4I1 expression was significantly associated with worse OS (p = 0.0073), while IDO1 expression did not reach statistical significance (p = 0.087). The combination of both markers led to a clinically significant stratification of patients. Especially p16-negative OPSCC with a high IL4I1 expression demonstrated poor survival. Immunologic differences between IDO1 and IL4I1 were detected in a TMA of 403 patients, with IDO1 and IL4I1 being expressed by HNSCC. A low IL4I1 expression in HNSCC led to a significantly better OS in this study, while IDO1 expression did not have a significant effect. Additional studies are necessary to investigate the complex interplay in the metabolic reprogramming of tumor cells.
Insights
High IL4I1 expression in head and neck squamous cell carcinoma (HNSCC) correlates with worse survival, while IDO1 expression shows no significant impact. Investigating these enzymes aids in understanding HNSCC immune evasion and developing targeted therapies.
Area of Science:
- Oncology
- Immunology
- Biochemistry
Background:
- Head and neck squamous cell carcinoma (HNSCC) presents challenges due to limited biomarkers and therapies.
- Metabolic reprogramming, particularly tryptophan metabolism, is crucial for immune evasion in HNSCC.
Purpose of the Study:
- To investigate the immunosuppressive roles of indoleamine 2,3-dioxygenase 1 (IDO1) and interleukin-4 induced 1 (IL4I1) in HNSCC.
- To assess IDO1 and IL4I1 as potential prognostic biomarkers in HNSCC.
Main Methods:
- Immunohistochemical analysis of IDO1 and IL4I1 expression in a tissue microarray (TMA) of 402 HNSCC patients.
- Correlation of enzyme expression with overall survival (OS) and clinical-pathological data.
Main Results:
- High IL4I1 expression was significantly associated with worse OS (p = 0.0073).
- IDO1 expression did not show a statistically significant association with OS (p = 0.087).
- Combined analysis stratified patients, with p16-negative oropharyngeal squamous cell carcinoma (OPSCC) and high IL4I1 showing particularly poor survival.
Conclusions:
- IL4I1 may serve as a significant prognostic biomarker in HNSCC, indicating poorer outcomes.
- IDO1's role requires further investigation, but IL4I1 warrants attention for therapeutic targeting.
- Understanding the interplay of metabolic reprogramming enzymes is vital for advancing HNSCC immunotherapy.
